JP2010198749A - Control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the number of load power lines and the number of control equipment such as power regulators, and to limit a load current. <P>SOLUTION: Nine first to ninth heaters 2-1 to 2-9 to heat a hot plate 1 are connected in a matrix form between three first power lines L1-1 to L1-3 in a row direction and three second power lines L2-1 to L2-3 in a column direction, the first to sixth power regulators 3-1 to 3-6 are controlled to select and drive the heaters 2-1 to 2-9, a load current flowing through the heaters is detected by a CT11, and the operation amount for the heaters is limited when the load current exceeds a limit value, thereby limiting the load current. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a control device such as a temperature controller that controls driving of a load such as a heater.

  Conventionally, for example, in temperature control in which an object to be heated is placed on a hot plate and subjected to heat treatment, the temperature regulator is heated based on a temperature detected from a temperature sensor disposed on the hot plate. This is performed by controlling energization of a heater disposed on the hot plate so that the temperature of the plate becomes the target temperature (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2001-274069

  When a plurality of heaters and a plurality of temperature sensors are arranged on the hot plate to control a plurality of control points, i.e., a plurality of channels, each heater and a power source can be driven individually. Are connected to each other via a power regulator having a built-in switching element, and each heater can be individually driven by controlling opening and closing of the switching element of the power regulator.

  For this reason, as the number of channels increases, the number of power regulators and the number of heater power lines increase, and the power lines are drawn longer between the heat plate and the power regulator. Wiring work becomes complicated.

  Furthermore, at the start of temperature control, that is, when starting up, all of the heaters are turned on at the same time, so the power consumption between them is significantly increased, and the power source and power with a large capacity that can withstand the large power consumption. An adjuster or the like is required, and accordingly, a large installation space needs to be secured and the cost is high.

  Further, in the case of load fluctuation, for example, in a halogen heater, an excessive current flows because the resistance value is very low when starting up at room temperature.

  The present invention has been made in view of the above-described problems, and it is an object of the present invention to reduce the number of load power lines and the number of power regulators and to limit the load current. .

  (1) In the control device of the present invention, a plurality of loads are connected between a plurality of first power lines and a plurality of second power lines, and the plurality of first power lines are a plurality of first opening / closing points. Each of the plurality of second power lines is connected to the power source via a plurality of second opening / closing means, respectively, and the plurality of first power lines and the plurality of second power lines are connected to the power source via each of the means. When two power lines are virtually arranged in parallel in the horizontal and vertical directions, one end of each of the plurality of loads is connected to the first power line at a portion where both power lines intersect. A control device for driving the plurality of loads by controlling an opening / closing amount of the first and second opening / closing means for adjusting the power supplied to the plurality of loads, the other end being connected to the second power line. Select the load to drive and Driving control means for calculating an operation amount for controlling the opening / closing amount of the first and second opening / closing means, and an output of a current sensor for detecting a current flowing in a power line between the power source and the load, Current limiting means for limiting an operation amount of the operation amount calculating means when a load current value flowing through the load exceeds a limit value.

  Examples of the load include a heater, a lamp, and a motor.

  The power source may be a DC power source or an AC power source.

  The opening / closing means may be a relay or a semiconductor element such as a transistor, a thyristor, or a triac.

 “The plurality of first power lines and the plurality of second power lines are virtually arranged in parallel in the horizontal direction and the vertical direction, respectively” means a plurality of first power lines and a plurality of second power lines. A virtual arrangement for defining the connection state between both power lines and the load regardless of the actual physical arrangement of the plurality of loads. Thus, this virtual arrangement does not constrain the actual physical arrangement of both power lines and loads.

  In addition, “arranged in parallel in the horizontal direction and the vertical direction” means that a plurality of first power lines are arranged in parallel in the horizontal direction (row direction) and a plurality of second power lines in the vertical direction (column direction). This means that the power lines are arranged in parallel. Therefore, there is a portion where both power lines intersect.

 “At the portion where both power lines intersect, one end of each of the plurality of loads is connected to the first power line and the other end is connected to the second power line” means both virtually arranged Corresponding to the portion where the power lines intersect, each load is electrically connected between both power lines.

  The plurality of first power lines and the plurality of second power lines are virtually arranged in parallel in the horizontal direction (row direction) and the vertical direction (column direction), respectively. Since it is connected between the power lines, each of the plurality of loads is connected in a matrix between the plurality of first power lines in the row direction and the plurality of second power lines in the column direction.

  It is preferable to connect loads to all of the intersections of both power lines to form a complete matrix connection. However, instead of connecting the loads to all of the intersections, the intersections where no loads are connected are used. There may be parts. That is, an incomplete matrix connection may be used. Further, when a load is not connected to the intersecting portion, a load connected to a power line different from the both power lines may be provided corresponding to the intersecting portion.

  The control device controls the power supplied to the load by controlling the opening / closing amount of the opening / closing means, and this power control is preferably ON / OFF control, phase control, cycle control, or the like.

  Selecting a load to be driven means that one load among a plurality of loads may be selected and driven, a plurality of loads may be selected and driven simultaneously, or all loads may be selected. May be driven simultaneously.

  The current sensor may be provided on each power line of the plurality of first power lines and the plurality of second power lines, or may be provided only on each power line of the plurality of first power lines, or a plurality of current sensors may be provided. Each power line of the second power line may be provided only, or at least one current sensor may be provided on a common power line.

  The current limiting unit preferably directly limits the operation amount of the operation amount calculating unit. However, the operation amount of the operation amount calculating unit may be indirectly limited by correcting a target value or the like.

  According to the control device of the present invention, by controlling the opening and closing of the first and second opening / closing means, a plurality of first power lines virtually arranged in parallel in the horizontal direction (row direction), and virtually Loads connected to intersections of a plurality of second power lines arranged in parallel in the vertical direction (column direction), that is, a plurality of first power lines in the row direction and a plurality of second power lines in the column direction Compared to the conventional example in which a plurality of loads connected in a matrix can be selected and driven, and each load is individually connected to a power source via a power regulator including a switching element. In addition, the number of power lines can be reduced, and the number of open / close means such as a power regulator can be reduced.

  Furthermore, when the load current flowing through the load is detected by a current sensor and the limit value is exceeded, the operation amount for controlling the opening / closing amount of the opening / closing means is limited to limit the load current, so an excessive current flows due to load fluctuations. Can be restricted. In addition, it is possible to limit the peak power when multiple loads are selected and driven at the same time. This eliminates the need for a large-capacity power supply or power regulator, and reduces the installation space accordingly. Cost can be reduced.

  (2) In another embodiment of the present invention, the current limiting means acquires the load current value based on the output of the current sensor in accordance with a timing for selecting a load to be driven.

  Acquiring the load current value according to the timing for selecting the load may acquire the load current value at the same timing as the timing for selecting the load, but the timing delayed for a certain period from the timing for selecting the load, For example, the load current value is acquired at a timing immediately before the next load is selected, and the predetermined period is preferably a period required for the current value to stabilize after the load is selected.

  The load current value based on the output of the current sensor refers to a load current value or the like obtained by full-wave rectifying and averaging the output of the current sensor.

  According to this embodiment, each time a load is selected and driven, a stable load current value based on the output of the current sensor is sampled, and it can be determined whether or not the load current value exceeds a limit value. .

  (3) In one embodiment of the present invention, the drive control means selects and drives one load among the plurality of loads in order.

  In addition to selecting and driving one of the plurality of loads in order, the control device selects two or more loads and drives them simultaneously, or drives all of the plurality of loads simultaneously. You may have.

  According to this embodiment, since loads are selected and driven one by one in order, one current sensor is provided on one power line in which a plurality of first power lines or a plurality of second power lines are shared. Thus, the load current of each load can be detected, and the number of current sensors can be reduced to one.

  (4) In the control device of the present invention, a plurality of loads are connected between the plurality of first power lines and the plurality of second power lines, and the plurality of first power lines are the plurality of first opening / closing points. Each of the plurality of second power lines is connected to the power source via a plurality of second opening / closing means, respectively, and the plurality of first power lines and the plurality of second power lines are connected to the power source via each of the means. When two power lines are virtually arranged in parallel in the horizontal and vertical directions, one end of each of the plurality of loads is connected to the first power line at a portion where both power lines intersect. A control device for driving the plurality of loads by controlling an opening / closing amount of the first and second opening / closing means for adjusting the power supplied to the plurality of loads, the other end being connected to the second power line. Select the load to drive and A drive control means for calculating an operation amount for controlling an opening / closing amount of the first and second opening / closing means, a load current flowing through the load is estimated based on the operation amount and a driving state of the plurality of loads, Current limiting means for limiting the amount of operation of the drive control means when the estimated load current value exceeds the limit value.

  According to the control device of the present invention, a matrix is formed between the plurality of first power lines in the row direction and the plurality of second power lines in the column direction by controlling opening and closing of the first and second opening / closing means. Multiple connected loads can be selected and driven. For each load, the number of power lines is reduced compared to the conventional example in which each load is connected to a power source via a power regulator including a switching element. In addition, the number of switching means such as a power regulator including a switching element can be reduced.

  Further, the load current flowing through the load is estimated, and when the estimated load current exceeds the limit value, the load current is limited by limiting the operation amount for controlling the switching amount of the switching means, so the load current is actually measured. Therefore, it is possible to prevent an excessive current from flowing due to the fluctuation of the load in advance. In addition, it is possible to limit the peak power when driving multiple loads at the same time. This eliminates the need for a large-capacity power supply, power regulator, etc., thereby reducing the installation space and cost. Can be reduced.

  (5) In another embodiment of the present invention, the current limiting means estimates a load current based on a resistance value corresponding to the operation amount and a driving state of the plurality of loads.

  The load drive state refers to a load selection state such as which load is selected and driven.

  According to this embodiment, the load current flowing through the load can be estimated based on the applied voltage based on the manipulated variable and the resistance value corresponding to the load driving state indicating which load is selected.

  (6) In one embodiment of the present invention, the current limiting means limits an operation amount corresponding to a plurality of loads selected and driven at the same rate.

  This ratio may be, for example, a ratio between the load current limit value and the load current estimated value.

  In this embodiment, when the estimated value of the load current flowing through the plurality of loads to be driven exceeds the limit value, the operation amounts respectively corresponding to the plurality of loads can be uniformly limited at the same rate.

  (7) In another embodiment of the present invention, the current limiting means calculates operation amounts corresponding to a plurality of selected and driven loads in order from the one having the largest absolute value of the deviation between the control amount and the target value. Restrict.

  According to this embodiment, when the estimated value of the load current flowing through the plurality of loads that are selected and driven exceeds the limit value, the manipulated variable is sequentially increased from the load of the channel in which the absolute value of the deviation between the controlled variable and the target value is large. Can be limited.

   (8) In still another embodiment of the present invention, the plurality of loads heats a control target, and the current limiting unit has an operation amount corresponding to the plurality of loads selected and driven. The control amount—the target value is limited in descending order.

  According to this embodiment, in the heating control, when the estimated value of the load current flowing through the plurality of loads that are selected and driven exceeds the limit value, the manipulated variable is set in order from the load of the channel having the largest control amount-target value. Can be limited. For example, if there are channels that have already exceeded the target value and are hotter than the target value, and there are low-temperature channels that have not yet reached the target value, the control amount minus the target value is a high value at which the value becomes a positive value. This channel is larger than the low-temperature channel in which the value is a negative value, so that the amount of operation corresponding to the load on the high-temperature channel is limited.

   (9) In another embodiment of the present invention, the plurality of loads cool a control target, and the current limiting unit is configured to select operation amounts corresponding to the plurality of loads that are selected and driven. The control amount—the target value is limited in ascending order.

  According to this embodiment, in the cooling control, when the estimated value of the load current flowing through a plurality of loads that are selected and driven exceeds the limit value, the manipulated variable is set in order from the load of the channel in which the control amount-target value is small. Can be limited. For example, if there is a channel that has already reached the target value and has a temperature lower than the target value, and a channel that has a high temperature that has not yet reached the target value, the control amount minus the target value becomes a negative value. Since the low-temperature channel is smaller than the high-temperature channel where the value is a positive value, the operation amount corresponding to the load of the low-temperature channel is limited.

  (10) In still another embodiment of the present invention, the current limiting means limits the operation amounts corresponding to a plurality of loads that are selected and driven in order from the smallest absolute value.

  According to this embodiment, when the estimated value of the load current flowing through the plurality of loads that are selected and driven exceeds the limit value, the operation amount can be limited in order from the smallest absolute value of the operation amount.

  (11) In still another embodiment of the present invention, when the load current value exceeds the limit value by the current limiting unit, an overcurrent state notifying unit for notifying that is provided.

  The overcurrent state notifying means preferably notifies the overcurrent state by display or contact output.

  According to this embodiment, when an overcurrent state is detected, it is notified so that the user can immediately grasp that the overcurrent state has occurred.

  (12) In the control device of the present invention, each end of the plurality of loads is connected to the power source via a common power line, and each other end is connected to the power source via a plurality of opening / closing means, A control device that drives the plurality of loads by controlling an opening / closing amount of the plurality of opening / closing means for adjusting power supplied to the plurality of loads, and selects a driving load and corresponds to the selected load. A load current that flows through the load based on an output of a drive control unit that calculates an operation amount that controls the amount of opening and closing of the plurality of switching units and a current sensor that detects a current flowing through a power line between the power source and the load. Current limiting means for limiting the operation amount of the operation amount calculating means when the value exceeds the limit value.

  According to the control device of the present invention, by controlling the opening / closing of the opening / closing means, a plurality of loads connected between the common power line and the opening / closing means can be selected and driven, and switching is performed for each load. Compared to a conventional example that is connected to a power source via a power regulator including elements and driven, the number of power lines can be reduced, and the number of switching means such as power regulators including switching elements can be reduced. it can.

  Further, when the load current flowing through the load is detected by a current sensor and the limit value is exceeded, the operation amount for controlling the opening / closing amount of the opening / closing means is limited to limit the current, so an excessive current flows due to load fluctuations. Can be limited. In addition, it is possible to limit the peak power when driving multiple loads at the same time. This eliminates the need for a large-capacity power supply, power regulator, etc., thereby reducing the installation space and cost. Can be reduced.

  (13) In the control device of the present invention, each end of the plurality of loads is connected to the power source via a common power line, and each other end is connected to the power source via a plurality of opening / closing means, A control device that drives the plurality of loads by controlling an opening / closing amount of the plurality of opening / closing means for adjusting power supplied to the plurality of loads, and selects a driving load and corresponds to the selected load. A drive control unit that calculates an operation amount for controlling an opening / closing amount of the plurality of opening / closing units; a load current that is estimated based on the operation amount and a driving state of the plurality of loads; and the load current that flows through the estimated load Current limiting means for limiting the amount of operation of the drive control means when the value exceeds the limit value.

  According to the control device of the present invention, by controlling the opening / closing of the opening / closing means, a plurality of loads connected between the common power line and the opening / closing means can be selected and driven, and switching is performed for each load. Compared to a conventional example that is connected to a power source via a power regulator including elements and driven, the number of power lines can be reduced, and the number of switching means such as power regulators including switching elements can be reduced. it can.

  Further, the load current flowing through the load is estimated, and when the estimated load current exceeds the limit value, the load current is limited by limiting the operation amount for controlling the switching amount of the switching means, so the load current is actually measured. Therefore, it is possible to prevent an excessive current from flowing due to the fluctuation of the load in advance. In addition, it is possible to limit the peak power when driving multiple loads at the same time. This eliminates the need for a large-capacity power supply, power regulator, etc., thereby reducing the installation space and cost. Can be reduced.

  According to the present invention, since a plurality of power lines are shared by a plurality of loads, the number of power lines and the number of power regulators including switching elements can be reduced as compared with the conventional example, and the power lines are routed. The space design and wiring work can be facilitated, and the cost can be reduced. Furthermore, it is possible to limit an excessive current from flowing due to load fluctuations. In addition, it is possible to limit the peak power when driving multiple loads at the same time. This eliminates the need for a large-capacity power supply, power regulator, etc., thereby reducing the installation space and cost. Can be reduced.

FIG. 1 is a schematic configuration diagram of a system including a temperature controller according to an embodiment of the present invention. It is a figure which shows the time division drive of nine heaters of FIG. It is a figure which shows the step response waveform of embodiment of FIG. It is a figure which shows the structure of the electric current detection part of FIG. It is a figure which shows the waveform of each part of FIG. It is a figure which shows the average current detected by the applied voltage of a heater, and a current detection part. It is a figure which shows the structure of the current limiting part of FIG. It is a flowchart with which it uses for operation | movement description of embodiment of FIG. It is a schematic block diagram of other embodiment of this invention. It is a figure which shows the structure of the current limiting part of FIG. It is a figure which shows the structure of the load current estimation part of FIG. It is a figure which shows the applied voltage by which the phase control was carried out. It is a figure which shows the state which selected the 1st heater. It is a figure explaining the synthetic | combination resistance value by the wraparound of an electric current. It is a figure which shows the example of the simultaneous drive of a some heater. It is a figure which shows the other example of the simultaneous drive of a some heater. It is a figure which shows the relationship between the ON (1) / OFF (0) state of the connection terminal corresponding to a some heater, and synthetic | combination resistance value. It is a flowchart with which it uses for operation | movement description of embodiment of FIG. It is a figure which shows the structure of the current limiting part of other embodiment of this invention. It is a flowchart with which it uses for operation | movement description of embodiment of FIG. It is a flowchart with which it uses for operation | movement description of embodiment of FIG. It is a figure corresponding to FIG. 1 of other embodiment of this invention. It is a figure which shows the time division drive of nine heaters of FIG. It is a schematic block diagram corresponding to FIG. 1 of other embodiment of this invention. It is a figure which shows the time division drive of nine heaters of FIG. It is a schematic block diagram of other embodiment of this invention. It is a figure which shows the time division drive of the three heaters of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a temperature control system including a temperature regulator 5 as a control device according to one embodiment of the present invention.

  This temperature control system controls nine channels to control the temperature of nine control points of the hot plate 1, and the hot plate 1 has nine first to ninth heaters 2 as loads. 1 to 2-9 and nine temperature sensors (not shown) are arranged.

  In this embodiment, the first to ninth heaters 2-1 to 2-9 include three first power lines L1-1 to L1 to 3 in the row direction and three second power lines in the column direction. A matrix connection is made between L2-1 to L2-3.

  That is, one end of each of the first to third heaters 2-1 to 2-3 is connected to the first power line L1-1 in the upper row direction, and each other end is the second in the three column directions. Are connected to the power lines L2-1 to L2-3. In addition, each one end of the fourth to sixth heaters 2-4 to 2-6 is connected to the first power line L1-2 in the middle row direction, and each other end is the second in the three column directions. Are connected to the power lines L2-1 to L2-3. Further, one end of each of the seventh to ninth heaters 2-7 to 2-9 is connected to the first power line L1-3 in the lower row direction, and each other end is connected to the third column direction first power line L1-3. Are connected to the two power lines L2-1 to L2-3, respectively.

  That is, when the three first power lines L1-1 to L1-3 are arranged in parallel in the row direction and the three second power lines L2-1 to L2-3 are arranged in parallel in the column direction, Each power line L1-1 to L1-3, L2-1 to L2-3 intersect, that is, at nine intersections, one end of each of the first to ninth heaters 2-1 to 2-9 is the first. The first power lines L1-1 to L1-3 are connected to each other, and the other ends are connected to the second power lines L2-1 to L2-3, respectively.

  Note that the three first power lines L1-1 to L1-3 are arranged in parallel in the row direction, and the three second power lines L2-1 to L2-3 are arranged in parallel in the column direction. This arrangement does not necessarily indicate the actual physical arrangement of the two power lines L1-1 to L1-3, L2-1 to L2-3, but both the power lines L1-1 to L1-3, L2-1 to L2. 3 is a virtual arrangement for clearly showing the connection state between the heaters 2-1 and 2-9.

  The connection terminals X1 to X3 of the three first row power lines L1-1 to L1-3 drawn from the hot plate 1 are first to third power regulators as first opening / closing means. It is connected to one end of the AC power supply 4 through 3-1 to 3-3. Further, the connection terminals Y1 to Y3 of the third power lines L2-1 to L2-3 in the three column directions drawn out from the hot plate 1 have fourth to sixth powers as second opening / closing means. It is connected to the other end of the AC power supply 4 via the adjusters 3-4 to 3-6.

  As described above, the nine heaters 2-1 to 2-9 include the three first power lines L1-1 to L1-3 in the row direction and the second power lines L2-1 to L2 in the three column directions. 3, the first to third power regulators 3-1 to 3-3 corresponding to the row direction and the fourth to sixth power regulators corresponding to the column direction. By controlling 3-4 to 3-6, any one of the heaters 2-1 to 2-9 can be selected and driven by electric power from the AC power supply 4.

  This temperature control system is an operation for nine channels calculated by performing PID calculation or the like based on detected temperatures (PV) from nine temperature sensors (not shown) arranged on the hot plate 1 and target temperatures. The temperature regulator 5 that distributes the amount to the first to sixth power regulators 3-1 to 3-6 described above and outputs the nine heaters 2 based on the operation amount from the temperature regulator 5. The above-mentioned first to sixth power regulators 3-1 to 3-6 that control the phase of AC power to 1 to 2-9 are provided.

  The temperature controller 5 includes a control amount input unit 6 to which detected temperatures from nine temperature sensors (not shown) arranged on the hot plate 1 are input, and a target value input to which a target temperature is input from a host device, for example. A drive target selection unit 8 for selecting a heater to be driven based on the detected temperature from the control unit 7, the control amount input unit 6, the detected temperature from the control amount input unit 6, and the target temperature from the target value input unit 7 The operation amount for 9 channels is calculated by performing PID calculation and the like, and the operation amount for 9 channels is calculated according to the heater selected by the drive target selection unit 8 as described later. And an operation amount calculation unit 9 that distributes and outputs to the sixth power adjusters 3-1 to 3-6. The drive target selection unit 8 and the operation amount calculation unit 9 constitute drive control means for selecting and driving the first to ninth heaters 2-1 to 2-9.

  In this embodiment, the load current flowing through the heater is measured for each channel, and when the load current becomes excessive due to load fluctuation or the like, the current value is limited to a predetermined current value.

  That is, as shown in FIG. 1, the temperature regulator 5 includes a CT (current transformer) 11 as a current sensor provided in the power line on the AC power supply 4 side with respect to the row-direction power regulators 3-1 to 3-3. Current detection unit 12 for detecting the load current flowing through the heater, load current limit value input unit 10 to which the limit value of the load current is input, and when a load current exceeding the limit value is detected And an overcurrent state notifying unit 14 for notifying it. Further, the operation amount calculation unit 9 has a function as a current limiting unit 13 that limits the operation amount and limits the load current as described later when a load current exceeding the limit value is detected by the current detection unit 12. is doing.

  The load current limit value input unit 10 is preliminarily set and inputted with a load current limit value for each channel.

  In the overcurrent state notification unit 14, for example, the overcurrent state is notified by error display or contact output by the display unit.

  In this embodiment, the temperature controller 5 drives the first to ninth heaters 2-1 to 2-9 one by one in time division, that is, scans one by one in order. .

  FIG. 2 is a diagram for explaining the time-division driving. FIG. 2A shows connection terminals X1, Y1 corresponding to the heaters 2-1 to 2-9 selected by the drive target selection unit 8. FIG. The selection state of X3 and Y3, FIG. 5B shows an example of the operation amount for the connection terminal X1 by the operation amount calculation unit 9, and FIG. 5C shows the connection amount for the connection terminal Y1 by the operation amount calculation unit 9. As an example of the manipulated variable, FIG. 4D shows the output of the current detection unit 12, and the overcurrent determination timing described later is indicated by an arrow. In FIG. 2, the connection terminals X1, Y1 to X3, Y3 individually corresponding to the first to ninth heaters 2-1 to 2-9 correspond to the first heater 2-1. Only the operation amounts for the connection terminals X1 and Y1 are representatively shown.

  First, as shown in FIG. 5A, the drive target selection unit 8 causes the connection terminals X1 and Y1 corresponding to the first channel, that is, the first heater 2-1, to move for a certain period t, for example, Next, the connection terminals X1 and Y2 corresponding to the second channel, that is, the second heater 2-2, are selected over the period t of 100 msec, and then selected over the period of 100 msec. The connection terminals X1 and Y3 corresponding to the third heater 2-3 are selected over a period t of 100 msec, and thereafter the fourth heater 2-4 to the ninth heater 2-9 are similarly selected. Are sequentially selected over a period t of 100 msec, and in the control cycle T, the heaters 2-1 to 2-9 are selected one by one in order.

  In the period t when the connection terminals X1 and Y1 corresponding to the first channel, that is, the first heater 2-1, are selected, the operation amount for the connection terminal X1 is calculated by the operation amount calculator 9 as follows. The operation amount of the first channel shown in FIG. 5B is 100%, and the operation amount for the connection terminal Y1 is 100% corresponding to ON as shown in FIG. As a result, the first power regulator 3-1 performs phase control according to the operation amount of the first channel, while the switching element of the fourth power regulator 3-4 is turned on, and the alternating current is changed. The electric power is phase-controlled and supplied to the first heater 2-1 to be driven.

  Next, during the period t when the connection terminals X1 and Y2 corresponding to the second channel, that is, the second heater 2-2 are selected, the operation amount calculator 9 operates the operation amount for the connection terminal X1. Is the operation amount of the second channel shown in FIG. 5B, and the operation amount for the connection terminal Y2 (not shown) is 100% corresponding to ON. The operation amount for the connection terminal Y1 is 0% corresponding to OFF as shown in FIG. Thus, the first power regulator 3-1 performs phase control according to the operation amount of the second channel, while the switching element of the fifth power regulator 3-5 is turned on, and the AC The electric power is phase-controlled and supplied to the second heater 2-2 for driving.

  Next, during the period t when the connection terminals X1 and Y3 corresponding to the third heater 2-3 are selected, the operation amount for the connection terminal X1 is calculated by the operation amount calculation unit 9 in FIG. The operation amount for the third channel shown in FIG. 5 is set to 100% corresponding to ON. The operation amount for the connection terminal Y1 is 0% corresponding to OFF as shown in FIG. Thus, the first power regulator 3-1 performs phase control according to the operation amount of the third channel, while the switching element of the sixth power regulator 3-6 is turned on, and the AC The electric power is phase-controlled and supplied to the third heater 2-3 to be driven.

  Thereafter, similarly, the fourth heater 2-4 to the ninth heater 2-9 are selected and driven in a time-sharing manner in order.

  FIG. 3 shows a step response waveform when the target temperature SP is changed by 10 ° C., FIG. 3A shows the target temperature SP, and FIG. 3B shows the detected temperature PV of each channel. Show. Since each channel is driven in turn, as shown in Fig. 5 (b), although there is some variation in temperature between channels, the temperature control performance for general purpose applications that do not require high accuracy is sufficient. It is.

  FIG. 4 is a diagram illustrating a configuration of the current detection unit 12 in FIG. 1, and FIG. 5 is a diagram illustrating an example of a waveform of each unit.

  The current detection unit 12 of this embodiment obtains the effective value of the load current from the average current using a low-pass filter (LPF). The current detection unit 12 includes a full-wave rectification unit 15 that performs full-wave rectification on the output shown in FIG. 5A from the current sensor CT11 as shown in FIG. 5B, and the full-wave rectification unit. As shown in FIG. 5C from the output of 15, a low-pass filter 16 that extracts only the DC component and makes it an average current, an A / D converter 17 that A / D converts the output of this low-pass filter 16, And a CPU 18 for calculating an effective value of the load current from the digital data from the A / D converter 17.

  The A / D converter 17 and the CPU 18 are included in a microcomputer 25 having various functions such as determination of overcurrent, calculation of an operation amount, and selection of a drive target.

  Since the average current is obtained by using the low-pass filter 16 in this way, the influence of power supply noise can be reduced. The cut-off frequency of the low-pass filter 16 is preferably about 20 Hz, for example.

  In this embodiment, the first to ninth heaters 2-1 to 2-9 are selected one by one in a time-sharing manner and driven in order, and the moment when the heater to be driven is selected, that is, the heater to be driven is selected. At the moment of switching, the current is not yet stable due to the time constant of the low-pass filter 16, and the load current may not be detected accurately.

  FIGS. 6A and 6B are diagrams showing the average current detected by the current detector 12 and the voltage applied to the heater. The period t (100 msec) in which the heater of each channel is selected and driven. ) Is also shown.

  After the application of the voltage controlled in phase according to the manipulated variable is started as shown in FIG. 4B, the average current detected by the current detector 12 is stabilized until the average current detected in FIG. As shown, about 50 msec is required.

  Therefore, in this embodiment, a certain period of time, for example, 70 msec has elapsed after switching according to the timing of selecting the heater to be driven, such as the timing of overcurrent determination indicated by the arrow in FIG. At the time, that is, before switching to the next heater to be driven, the average current is sampled to determine the presence or absence of overcurrent.

  FIG. 7 is a diagram illustrating a configuration of a main part of the operation amount calculation unit 9 including the current limiting unit 13 of FIG.

  The operation amount calculation unit 9 operates each channel based on the deviation between the target temperature SP of each channel from the target value input unit 7 and the detected temperature PV of each channel that is the control amount from the control amount input unit 6. PID calculation units 21-1 to 21-9 that respectively calculate amounts are provided, and each PID calculation unit 21-1 to 21-9 is connected to a selection unit 22 that is controlled by the drive target selection unit 8. The target temperature SP of each channel is given in order, and the operation amount of each channel is calculated in order.

  Based on the operation amount of each channel calculated in turn by each PID calculation unit 21-1 to 21-9, each power regulator 3-1 to 3-6 is controlled as shown in FIG. The channel heaters are driven in turn.

  The current limiter 13 includes a subtractor 23-1 to 23-9 that subtracts the current limit value of each channel of the load current limit value input unit 10 from the load current of each channel detected by the current detector 12, and a drive A selection unit 24 for selecting each channel in turn by the target selection unit 8, PI calculation units 19-1 to 19-9 for performing PI calculations on the outputs of the subtraction units 23-1 to 23-9, and the calculation results thereof Lower limiters 20-1 to 20-9 for limiting the negative side of the output, and the outputs of the lower limiters 20-1 to 20-9 are obtained from the integral operation amounts of the respective PID calculation units 21-1 to 21-9. The subtracted PID operation amount is used as the output operation amount.

  The current detector 12 detects the load current flowing through the heaters that are selected and driven in order. The selection unit 24 is controlled by the drive target selection unit 8 and the same channel as the selection unit 22 is selected.

  FIG. 7 shows a state where the second channel is selected. For example, in a state where the second channel is selected, the PID operation amount is calculated by the second PID calculation unit 21-2, and the PID operation amount is connected as shown in FIG. The operation amount for the connection terminal X1 is 100%, and the operation amount for the connection terminal Y2 is 100% corresponding to ON. Thus, the first power regulator 3-1 performs phase control according to the operation amount of the second channel, while the switching element of the fifth power regulator 3-5 is turned on, and the AC The electric power is phase-controlled and supplied to the second heater 2-2 for driving.

  When the load current flowing through the second heater 2-2 is detected by the current detection unit 12 and exceeds the limit value of the load current limit value input unit 10, the output of the subtraction unit 23-2 becomes positive. . The output of the subtracting unit 23-2 is PI-calculated by the PI calculating unit 19-2 and given to the second PID calculating unit 21-2 via the lower limiter 20-2. Subtracted from the integral operation amount, the PID operation amount is limited, and thereby the load current flowing through the heater 2-2 is limited.

  Further, when the load current flowing through the heater 2-2 does not exceed the limit value, the output of the PI calculation unit 19-2 is limited to “0” by the lower limiter 20-2. Therefore, the PID calculation unit 21-2 The PID operation amount is not limited.

  In this way, the heaters of the respective channels are driven in order, and when the load current flowing through the heater exceeds the limit value, the operation amount is reduced by that amount and the load current is limited.

  FIG. 8 is a flowchart for explaining the above-described current limiting operation.

  The heaters of each channel are selected and driven in order, the actual load current flowing through the driving heater is measured (step n1), and it is determined whether or not the measured load current is within the limit value. (Step n2) When it is within the limit value, the process ends.

  In step n2, when the measured load current is not within the limit value, the current limit unit 13 integrates the limit operation amount for limiting the operation amount (step n3), and from the integral operation amount calculated by the PID calculation unit. The result obtained by subtracting the limit operation amount is ended as the output operation amount (step n4).

  As described above, the first to ninth heaters 2-1 to 2-1 are arranged between the first power lines L1-1 to L1-3 in the row direction and the second power lines L2-1 to L2-3 in the column direction. Since 2-9 are connected in a matrix and selectively driven in order, the number of power lines and the number of power lines are compared with the conventional example in which each heater is individually connected to a power source via a power regulator including a switching element. The number of power regulators including switching elements can be reduced. This facilitates space design and wiring work for routing the power line, and can reduce the cost.

  Furthermore, when the load current flowing through the heater exceeds the limit value, the operation amount is limited to limit the load current, so that it is possible to limit an excessive current flow due to a load variation or the like.

(Embodiment 2)
FIG. 9 is a schematic configuration diagram of a temperature control system including a temperature regulator 5-1 according to another embodiment of the present invention, and parts corresponding to those in FIG.

  In the above embodiment, the load current is actually measured to limit the overcurrent. However, in this embodiment, the load current is not actually measured, and the load current is predicted to prevent the overcurrent from flowing. To do.

  In this embodiment, the operation amount calculation unit 9-1 has a function as the current limiting unit 13-1, and the current limiting unit 13-1 calculates the load current based on the operation amount as described later. When the estimated load current exceeds the limit value, the operation amount is limited so that the load current exceeding the limit value does not flow.

  FIG. 10 is a diagram illustrating a configuration of a main part of the operation amount calculation unit 9-1 including the current limiting unit 13-1 illustrated in FIG.

  The current limiting unit 13-1 of this embodiment includes a reference resistance value storage unit 26 that stores in advance the resistance values of the first to ninth heaters 2-1 to 2-9 as reference resistance values, and the reference resistance value storage. A load current estimating unit 27 for estimating the load current of each channel based on the reference resistance value of the unit 26 and the operation amount of the PID from each of the PID calculating units 21-1 to 21-9, and the load current limit value input unit 10 A division unit 28 for calculating the ratio between the load current limit value and the estimated load current value, an upper limiter 29 for limiting the calculated ratio to 1 or less, and a ratio for which the upper limit is limited by the upper limiter 29 are set. And multipliers 30-1 to 30-9.

  In the reference resistance value storage unit 26, the heaters 2-1 to 2-9 are selected and driven one by one in order, and the applied voltage based on the operation amount (output phase angle) and the CT11 of FIG. Based on the current value detected by the current detection unit 12 from the output, the resistance value of each of the heaters 2-1 to 2-9 is calculated, and the calculated resistance value is stored as a reference resistance value.

  As shown in FIG. 11, the load current estimation unit 27 calculates an output phase angle indicating the ratio of the applied voltage of the heater based on the operation amount of the PID from the PID calculation units 21-1 to 21-9. An angle calculation unit 31, an applied voltage calculation unit 32 that calculates an applied voltage of the heater from the output phase angle, and a synthesis that calculates a combined resistance value according to the reference resistance value of the reference resistance value storage unit 26 and the driving state of the heater A resistance calculation unit 33 and a load current estimation calculation unit 34 that calculates an estimated value of the load current from the combined resistance value and the applied voltage are provided.

  FIG. 12 shows the voltage applied to the phase-controlled heater, and the output phase angle calculation unit 31 calculates the output phase angle shown in FIG. 12 based on the operation amount.

  FIG. 13 is a diagram for explaining calculation of the combined resistance value in the combined resistance calculator 33.

  Here, for the sake of simplicity, the resistance value of each of the heaters 2-1 to 2-9 is set to 20Ω, and the first and fourth switches 35 of the connection terminals X1 and Y1 corresponding to the first heater 2-1. A state is assumed in which -1 and 35-4 are turned on and the first heater 2-1 is selected and driven.

  In this state, as shown in FIG. 14A, a sneak loop is formed by current sneaking, and as shown in FIGS. 14B and 14C, the resistance value of the first heater 2-1 is 20Ω. In addition, this is equivalent to connecting a resistance value of 25Ω by another heater in parallel, and the combined resistance value is 11.1Ω.

  Thus, according to which heater is driven, the combined resistance calculator 33 can calculate the combined resistance value based on the reference resistance value.

  Since the applied voltage calculation unit 32 in FIG. 11 calculates the applied voltage based on the manipulated variable, the load current estimation calculation unit 34 estimates the load current of each channel based on the applied voltage and the combined resistance value. A value can be calculated.

  In this embodiment, as shown in FIG. 10, when the operation amount of the channel corresponding to the heater to be driven is calculated by the corresponding PID calculation units 21-1 to 21-9, the load current estimation unit 27 calculates the operation amount. As described above, the load current flowing through the heater to be driven is estimated from the applied voltage based on the manipulated amount and the combined resistance based on the reference resistance value of the reference resistance value storage unit 26, and the load current limit is performed by the division unit 28. A ratio r (= limit value of load current / estimated value of load current) between the limit value of the load current of the corresponding heater of the value input unit 10 and the estimated value of the load current is calculated, and this ratio r is the upper limit limiter 29. Are set in the multipliers 30-1 to 30-9 of the corresponding channels, and are multiplied by the operation amounts of the PIDs from the corresponding PID calculation units 21-1 to 21-9. The ratio r is fed back to the PID calculation units 21-1 to 21-9 of the corresponding channels, and the operation amount corrected by the multipliers 30-1 to 30-9 is adjusted.

  For example, as in the first embodiment, in the state where the second channel is selected, the operation amount of the PID is calculated by the second PID calculation unit 21-2, and this operation amount is calculated as the load current estimation unit. 27. The load current estimation unit 27 estimates the load current of the second channel based on the manipulated variable and the reference resistance value of the reference resistance value storage unit 26, and the division unit 28 calculates the limit value and load current of the second channel. The ratio r to the estimated value is calculated and set in the multiplier 30-2 via the upper limiter 29 and fed back to the PID calculation unit 21-2.

  When the load current estimated by the load current estimating unit 27 exceeds the limit value of the load current limit value input unit 10, the ratio r (= the limit value of the load current / the estimated value of the load current) is “1”. The ratio r is set in the multiplier 30-2 without being limited by the upper limiter 29, and the PID operation amount from the PID calculation unit 21-2 is multiplied by the ratio r to operate the PID. The amount is limited.

  Since there is a difference between the PID operation amount from the PID calculation unit 21-2 and the PID operation amount that is actually output and multiplied by the ratio r, the PID calculation unit 21-2 provides feedback. The difference is subtracted from the integral operation amount based on the ratio r.

  Thus, the heaters 2-1 to 2-9 of each channel are selected and driven in order, and the load current of each channel is estimated from the combined resistance value and the applied voltage based on the operation amount (output phase angle). When the estimated load current exceeds the limit value, the operation amount is reduced by the multipliers 30-1 to 30-9 according to the ratio.

  Thereby, it is possible to prevent the load current exceeding the limit value from flowing without measuring the load current in advance.

  Other configurations are the same as those of the above-described embodiment.

  The above is a case where each heater 2-1 to 2-9 is selected and driven one by one in time division, but in this embodiment, even when a plurality of heaters are simultaneously selected and driven. Can be applied.

  Here, examples of simultaneously driving a plurality of heaters are shown in FIGS.

  FIG. 15 shows an example in which heaters that are driven simultaneously are arranged in the row direction. For example, the first and second heaters 2-1 and 2-2 are operated at 50% and 70%, respectively. An example in the case of driving is shown. In this case, the operation amount 100% is output to the power adjuster 3-1 in the corresponding row, and the operation amounts 50% and 70% are output to the corresponding power adjusters 3-4 and 3-5 in the column direction, respectively.

  Similarly, when the heaters that are driven simultaneously are arranged in the column direction, 100% of the operation amount is output to the power regulator in the corresponding column, and the operation amount of the heater to be driven is output to the corresponding power adjuster in the row direction. .

  FIG. 16 shows the case where the heaters 2-1, 2-3, 2-7, 2-9 that are driven simultaneously are arranged in the row direction and the column direction, and the heaters 2-1, 2 arranged in the column direction. -7; an example in which the operation amounts of 2-3 and 2-9 are the same. For example, the operation amounts of the first heater 2-1 and the seventh heater 2-7 are both 90%. This shows a case where the operation amounts of the third heater 2-3 and the ninth heater 2-9 are both 70%. In this case, the operation amount 100% is output to the power regulators 3-1 and 3-3 in the corresponding row, and the operation amounts 90% and 70% are output to the corresponding power regulators 3-4 and 3-6 in the column direction. To do.

  Similarly, when the operation amounts of the heaters arranged in the row direction are the same, the operation amount of 100% is output to the power adjuster in the corresponding column, and the operation amounts of the heaters driven to the corresponding power adjuster in the row direction are respectively output To do.

  The above is merely an example of driving, and a plurality of heaters may be driven simultaneously in various combinations.

  Even when a plurality of heaters are selected and driven at the same time as described above, the combined resistance value due to current sneaking is calculated in the same manner as when one heater 2-1 shown in FIG. 14 is selected and driven. can do.

  FIG. 17 shows the switches 35-1 to 35-3 connected to the connection terminals X1 to X3 in the row direction of FIG. 13 and the switches 35-4 to 35 connected to the connection terminals Y1 to Y3 in the column direction. FIG. 17 shows an example of the combined resistance value according to the ON “1” / OFF “0” state of −6, that is, which heater is selected and driven. This FIG. 17 is different from the above. The example which computed the resistance value of each heater 2-1 to 2-9 as 10 ohms is shown.

  As shown in FIG. 17, for example, any one of the connection terminals X1 to X3 in the row direction is turned on, that is, any one of X1 to X3 is “1”, and When any one of the connection terminals Y1 to Y3 is turned on, that is, when any one of Y1 to Y3 is “1”, the combined resistance value is 5.6Ω. In addition, for example, when any two switches of the row direction connection terminals X1 to X3 are turned on and any one of the column direction connection terminals Y1 to Y3 is turned on, or the row direction connection is performed. When any one of the terminals X1 to X3 is turned on and any two switches of the connection terminals Y1 to Y3 in the column direction are turned on, the combined resistance value is 3.9Ω. For example, when any two switches of the connection terminals X1 to X3 in the row direction are turned on and any two switches of the connection terminals Y1 to Y3 in the column direction are turned on, the impedance is 2.2Ω. Furthermore, when all the switches of the row direction connection terminals X1 to X3 are turned on and any one of the column direction connection terminals Y1 to Y3 is turned on, or the row direction connection terminals X1 to X3 are turned on. When any one switch of X3 is turned on and all the switches of the connection terminals Y1 to Y3 in the column direction are turned on, it becomes 3.3Ω. Further, when all the switches of the connection terminals X1 to X3 in the row direction are turned on and any two switches of the connection terminals Y1 to Y3 in the column direction are turned on, or the connection terminals X1 to X1 in the row direction When any two switches of X3 are turned on and all the switches of the connection terminals Y1 to Y3 in the column direction are turned on, 1.7Ω is obtained. Further, when all the switches of the connection terminals X1 to X3 in the row direction are turned on and all of the switches of the connection terminals Y1 to Y3 in the column direction are turned on, 1.1Ω is obtained.

  As described above, measurement was performed in advance according to the on / off F state of the switches of the row direction connection terminals X1 to X3 and the column direction connection terminals Y1 to Y3, that is, the state of selecting and driving the heater. The combined resistance value can be calculated from the reference resistance value of each heater. That is, when one or more of the first to ninth heaters 2-1 to 2-9 are selected and driven, the combined resistance value can be calculated from the reference resistance value according to the driving state.

  Therefore, in FIG. 10 described above, when the drive target selection unit 8 selects one or more heaters and drives them simultaneously, a plurality of PID calculation units 21-1 to 1-9 corresponding to the selected channel are used. The PID operation amount is calculated for each. From the applied voltage based on the calculated PID manipulated variable and the combined resistance value based on the reference resistance value of the reference resistance value storage unit 26, the load current estimating unit 27 estimates the total load current of the selected channel. . The load current limit value input unit 10 is preliminarily set and inputted with a limit value of a total load current when a plurality of heaters are driven simultaneously.

  When the load current estimated by the load current estimating unit 27 exceeds the limit value of the total load current when the heaters of the selected channels are simultaneously driven, the ratio r (= total of the selected channels) As described above, the PID operation amount of the selected channel is the same by the multipliers 30-1 to 30-9 in accordance with the load current limit value / the estimated value of the total load current of the selected channel). It is uniformly limited by the ratio r.

  FIG. 18 is a flowchart for explaining the current limiting operation when the one or more heaters are driven simultaneously.

  A list of one or more drive target heaters selected by the drive target selection unit 8 is created (step n1), and the total load is calculated from the combined resistance value of the selected heater and the applied voltage based on the operation amount of the PID. An estimated current value is calculated (step n2), and it is determined whether or not the estimated load current is within the limit value of the total load current (step n3). When the limit value is exceeded in step n3, the ratio r (= total load current limit value / total load current estimate value) between the total load current limit value and the total load current estimate value is calculated. The operation amount is limited by multiplying the operation amount of PID from the PID operation units 21-1 to 21-9 corresponding to the selected heater by the ratio r by the corresponding multipliers 30-1 to 30-9. To limit the current. Further, the ratio r is fed back to the corresponding PID calculation units 21-1 to 21-9 to subtract the integral operation amount (step n4).

  As described above, when a plurality of heaters are selected and driven simultaneously, the total load current is estimated. When the estimated total load current exceeds the limit value, the operation amount for the plurality of heaters is limited. For example, it becomes possible to limit the peak power at the start of temperature control, that is, at the time of start-up, thereby eliminating the need for a large-capacity power supply or power regulator and reducing the installation space accordingly. At the same time, the cost can be reduced.

  In this embodiment, the operation amount is restricted by uniformly multiplying the operation amount of the PID of the plurality of selected heaters by the ratio r. However, as another embodiment of the present invention, as shown in FIG. An amount distribution unit 36 may be provided to vary the amount of operation limit according to the channel.

Although not shown, the limit amount distribution unit 36 receives a target temperature, a detected temperature, and an operation amount corresponding to a channel to be selected and driven. Based on these, the limit amount of the operation amount is input to the channel. The ratios r _{1 to} r ₉ of the multipliers 30-1 to 30-9 corresponding to the channels are set.

  FIG. 20 is a flowchart for explaining the operation of the limit amount distribution unit 36.

  A list of heaters to be driven selected by the drive target selection unit 8 is created (step n1), and an estimated value of the total load current is calculated from the combined resistance value and the applied voltage based on the operation amount for the selected heater. (Step n2), it is determined whether or not the estimated total load current is within the limit value of the total load current of the selected heater (Step n3). To do.

  In step n3, when the limit value is exceeded, it is determined whether or not there is one heater to be driven (step n4), and when it is one, an operation amount not exceeding the load current is obtained (step n5). The operation amount of the corresponding PID calculation unit is limited and the process ends (step n6).

When the number of heaters to be driven is not one in step n4, that is, when a plurality of heaters are selected, a heater with a channel whose amount exceeds the target temperature is searched, and there is no channel that exceeds the target temperature. For example, a channel with a small deviation is searched. The heater of the channel selected by the search is removed from the list, and the operation amount of the heater removed from the list is set to “0”, that is, the ratios r _{1 to} r of the multipliers 30-1 to 30-9 corresponding to the heater. _{9 is set} to “0”, and the integral amount of the PID calculation units 21-1 to 21-9 corresponding to the heater is subtracted, and the process returns to step n 2 (step n 7). Similar processing is performed.

  As described above, until the estimated load current value falls within the limit value, the operation amount of the heater of the channel that exceeds the target temperature or the heater of the channel with a small deviation is limited. Thus, the load current can be limited.

  As another embodiment, the operation amount may be limited as shown in the flowchart of FIG.

  That is, a list of heaters to be driven selected by the drive target selection unit 8 is created (step n1), and the total number of heaters selected from the combined resistance value and the applied voltage based on the operation amount for the selected heater is selected. Is calculated (step n2), and it is determined whether or not the estimated total load current is within the limit value of the total load current of the selected heater (step n3). When it is within the limit value, the process ends.

  When the estimated value of the load current exceeds the limit value at step n3, it is determined whether or not there is one heater to be driven (step n4), and when there is one, the operation amount that does not exceed the load current is determined. Determination (step n5) and the operation amount of the corresponding PID calculation unit are limited (step n6).

  When the number of heaters to be driven is not one in step n4, that is, when a plurality of heaters are selected, a heater for a channel with a small operation amount is searched, and a heater for a channel selected by the search is removed from the list. The operation amount of the drive target removed from the list is set to “0”, the integral amount of the PID calculation unit corresponding to the heater is subtracted, and the process returns to step n2 (step n7). Similar processing is performed.

  As described above, the operation amount of the heater with a small operation amount is limited until the estimated value of the load current falls within the limit value, so that the time until the temperature of the channel with the limited operation amount is recovered is short. It becomes.

(Embodiment 3)
FIG. 22 is a schematic configuration diagram corresponding to FIG. 1 of another embodiment of the present invention, and corresponding portions are denoted by the same reference numerals.

  In this embodiment, instead of the first to sixth power regulators 3-1 to 3-6 described above, the first to sixth SSRs 37-1 to 37-6 and power regulators for controlling them are used. A PWM controller 38 is provided. This PWM controller 38 controls the average supply power to the load by changing the ratio between the number of conduction cycles and the number of non-conduction cycles by turning on the switching element in accordance with the cycle control, that is, at the time of zero voltage of the AC power supply. It is.

  FIG. 23 is a diagram for explaining time-division driving of this embodiment, and corresponds to FIG. 2 described above. FIG. 4A shows the selection state of the connection terminals X1, Y1 to X3, Y3 corresponding to the heaters 2-1 to 2-9 selected by the drive target selection unit 8, and FIG. An example of the operation amount for the connection terminal X1 by the calculation unit 9-1, FIG. 10C shows an example of the operation amount for the connection terminal Y1 by the operation amount calculation unit 9-1, and FIG. The outputs of the current detectors 12 are respectively shown, and the abnormality determination timing is indicated by arrows. In FIG. 23, among the connection terminals X1, Y1 to X3, Y3 individually corresponding to the first to ninth heaters 2-1 to 2-9, it corresponds to the first heater 2-1. Only the operation amounts for the connection terminals X1 and Y1 are representatively shown.

  First, as shown in FIG. 2A, the first channel, that is, the connection terminals X1 and Y1 corresponding to the first heater 2-1 are selected over a fixed period t, for example, 100 msec. Next, the connection terminals X1 and Y2 corresponding to the second channel, that is, the second heater 2-2 are selected over the same period t of 100 msec, and then the third heater 2- 3 is selected over a period t of 100 msec, and thereafter, similarly, a period t of 100 msec in order from the fourth heater 2-4 to the ninth heater 2-9 is similarly selected. In the control cycle T, the heaters 2-1 to 2-9 are selected in order.

  In the period t when the connection terminals X1, Y1 corresponding to the first channel, that is, the first heater 2-1, are selected, the operation amount for the connection terminal X1 is as shown in FIG. The operation amount for one channel is 100% corresponding to the on state, as shown in FIG. As a result, the PWM controller 38 performs cycle control on the first SSR 37-1 according to the operation amount of the first channel, while controlling the contact point of the fourth SSR 37-4 to be in the ON state. The first heater 2-1 is driven according to the controlled power.

  Next, during the period t when the connection terminals X1 and Y2 corresponding to the second channel, that is, the second heater 2-2 are selected, the operation amount for the connection terminal X1 is as shown in FIG. The operation amount for the connection terminal Y2 (not shown) is 100% corresponding to ON. The operation amount for the connection terminal Y1 is 0% corresponding to OFF as shown in FIG. As a result, the PWM controller 38 performs cycle control on the first SSR 37-1 according to the operation amount of the second channel, while controlling the contact of the fifth SSR 37-5 to be in the ON state. The second heater 2-2 is driven according to the controlled power.

  Next, during the period t when the connection terminals X1 and Y3 corresponding to the third heater 2-3 are selected, the operation amount for the connection terminal X1 is the third channel shown in FIG. The operation amount for the connection terminal Y3 (not shown) is 100% corresponding to ON. The operation amount for the connection terminal Y1 is 0% corresponding to OFF as shown in FIG. As a result, the PWM controller 38 performs cycle control on the first SSR 37-1 according to the operation amount of the third channel, while controlling the contact of the sixth SSR 37-6 to be in the ON state. The third heater 2-3 is driven according to the controlled power.

  As described above, the first to third heaters 2-1 to 2-3 in the first row direction are driven in a time-sharing manner and by cycle control corresponding to the operation amount.

Similarly, the fourth to ninth heaters 2-4 to 2-9 in the second and third row directions are driven in a time-sharing manner and by cycle control corresponding to the operation amount.
Other configurations are the same as those in the first embodiment.

(Embodiment 4)
FIG. 24 is a schematic configuration diagram corresponding to FIG. 1 of another embodiment of the present invention, and portions corresponding to FIG. 1 are denoted by the same reference numerals.

  In this embodiment, instead of the first to sixth power regulators 3-1 to 3-6 described above, first to sixth switches 39-1 to 39-6 are provided and one power regulator is provided. The phase control according to the operation amount is performed by the device 40.

  The first to sixth switches 39-1 to 39-6 are made of, for example, semiconductor elements, and the operation amount calculation unit 9-2 time-divides the first to ninth heaters 2-1 to 2-9. On / off control is performed so as to drive in order. The power adjuster 40 performs phase control according to the operation amount from the operation amount calculation unit 9-2.

  FIG. 25 is a diagram for explaining the time-division driving of this embodiment, and corresponds to FIG. 2 described above. FIG. 8A shows the selection state of the connection terminals X1, Y1 to X3, Y3 corresponding to the heater selected by the drive target selection unit 8, and FIG. 9B shows the operation amount calculation unit 9-2. The on / off state of the first switch 39-1 for the connection terminal X1 is shown in FIG. 4C, where the fourth switch 39-4 for the connection terminal Y1 controlled by the operation amount calculator 9-2. FIG. 4D shows an example of the operation amount by the operation amount calculation unit 9-2, FIG. 4E shows the output of the current detection unit 12, and the abnormality determination timing is indicated by an arrow. Is shown. FIG. 25 representatively shows only the on / off states of the first and fourth switches 39-1 and 39-4 for the connection terminals X1 and Y1 corresponding to the first heater 2-1. .

  First, as shown in FIG. 2A, the first channel, that is, the connection terminals X1 and Y1 corresponding to the first heater 2-1 are selected over a fixed period t, for example, 100 msec. At this time, the first switch 39-1 for the connection terminal X1 is turned on as shown in FIG. 2B, and the fourth switch 39-4 for the connection terminal Y1 is also shown in FIG. It is turned on as shown in (c). As a result, the power regulator 40 applies the first channel shown in FIG. 4D to the first heater 2-1 selected by the first and fourth switches 39-1 and 39-4. The first heater 2-1 is driven by performing phase control according to the operation amount.

  Next, as shown in FIG. 6A, the second channel, that is, the connection terminals X1 and Y2 corresponding to the second heater 2-2 are selected over a period t of 100 msec. The first switch 39-1 for the connection terminal X1 is maintained in the ON state as shown in FIG. 2B, and the fifth switch 39-5 for the connection terminal Y2 (not shown) is in the ON state. On the other hand, the fourth switch 39-4 for the connection terminal Y1 is turned off as shown in FIG. As a result, the power regulator 40 applies the second channel shown in FIG. 4D to the second heater 2-2 selected by the first and fifth switches 39-1 and 39-5. The second heater 2-2 is driven by performing phase control according to the operation amount.

  Next, as shown in FIG. 5A, the third channel, that is, the connection terminals X1 and Y3 corresponding to the third heater 2-3 are selected over a period t of 100 msec. The first switch 39-1 for the connection terminal X1 is maintained in the ON state as shown in FIG. 2B, and the sixth switch 39-6 for the connection terminal Y3 (not shown) is in the ON state. On the other hand, the fourth switch 22-4 for the connection terminal Y1 is turned off as shown in FIG. As a result, the power regulator 40 applies the third channel shown in FIG. 4D to the third heater 2-3 selected by the first and sixth switches 39-1 and 39-6. The third heater 2-3 is driven by performing phase control according to the operation amount.

  As described above, the first to third heaters 2-1 to 2-3 in the first row direction are driven in a time-sharing manner and by phase control corresponding to the operation amount.

Similarly, the fourth to ninth heaters 2-4 to 2-9 in the second and third row directions are driven in a time-sharing manner and according to the operation amount.
Other configurations are the same as those of the first embodiment.

(Embodiment 5)
In each of the above-described embodiments, the heaters 2-1 to 2-9 of the hot plate 1 are connected in a matrix, but as another embodiment of the present invention, a plurality of heaters may be connected as one column or one row. For example, as shown in FIG. 26, three heaters 2-1 to 2-3 are connected in a row, and power line connecting terminals X1, X2, and X3 at each end of each heater 2-1 to 2-3. Are connected to one end of the AC power supply 4 via the first to third SSRs 37-1 to 37-3 controlled by the PWM controller 38, respectively, while the other ends of the heaters 3-1 to 3-3 are connected to each other. The connection terminal Y of the power line connected in common may be connected to the other end of the AC power supply 4.

  FIG. 27 is a diagram for explaining time-division driving according to this embodiment, and corresponds to FIG. 23 described above. FIG. 6A shows the selection state of the connection terminals X1 to X3 corresponding to the heaters 2-1 to 2-3 selected by the drive target selection unit 8, and FIG. (C) shows an example of the operation amount for the connection terminal X2 by the operation amount calculation unit 9-1, and (d) shows the operation amount calculation unit. FIG. 9E shows an example of the operation amount for the connection terminal X3 by 9-1, and FIG. 9E shows the output of the current detection unit 12, respectively, and the abnormality determination timing is indicated by an arrow.

  First, as shown in FIG. 5A, the first channel, that is, the connection terminal X corresponding to the first heater 2-1, is selected over a certain period t, for example, a period of 100 msec, Next, the connection terminal X2 corresponding to the second channel, that is, the second heater 2-2 is selected over the same period t of 100 msec, and then corresponds to the third heater 2-3. Similarly, the connection terminal X3 is selected over a period t of 100 msec.

  In the period t when the connection terminal X1 corresponding to the first channel, that is, the first heater 2-1, is selected, the operation amount for the connection terminal X1 is the first amount shown in FIG. The operation amount for the channel is the operation amount for the connection terminals X2 and X3, and is 0% corresponding to OFF, as shown in FIGS. As a result, the PWM controller 38 performs cycle control on the first SSR 37-1 according to the operation amount of the first channel, while the contacts of the second and third SSRs 37-2 and 37-3 are connected. The first heater 2-1 is driven in accordance with the cycle-controlled power, which is controlled to the off state.

  Next, in the period t when the connection terminal X2 corresponding to the second channel, that is, the second heater 2-2 is selected, the operation amount for the connection terminal X2 is shown in FIG. The amount of operation for the second channel is 0% for the connection terminals X1 and X3, corresponding to OFF, as shown in FIGS. As a result, the PWM controller 38 performs cycle control on the second SSR 37-2 in accordance with the operation amount of the second channel, while the contacts of the first and third SSRs 37-1, 37-3 are connected. The second heater 2-2 is driven in accordance with the cycle-controlled electric power, which is controlled to the off state.

  Next, during the period t when the connection terminal X3 corresponding to the third heater 2-3 is selected, the operation amount for the connection terminal X3 is the operation of the third channel shown in FIG. The operation amount for the connection terminals X1 and X2 is 0% corresponding to OFF, as shown in FIGS. As a result, the PWM controller 38 performs cycle control corresponding to the operation amount of the third channel for the third SSR 37-3, while the contacts of the first and second SSRs 37-1, 37-2 are connected. The third heater 2-3 is driven in accordance with the cycle-controlled power, which is controlled to the off state.

  Other configurations are the same as those in the first embodiment.

(Other embodiments)
In Embodiments 1 to 3 to 5 described above, one heater among a plurality of heaters is selected and driven in order. However, as another embodiment, a plurality of heaters may be selected and driven simultaneously. . In this case, the total load current of a plurality of heaters may be detected, and the operation amount may be limited when the total load current limit value is exceeded, or the load current of each heater can be detected. In this way, the operation amount may be limited when the load current exceeds the limit value.

  The present invention is useful for a system for driving a plurality of loads.

DESCRIPTION OF SYMBOLS 1 Heat plate 2-1 to 2-9 Heater 3-1 to 3-6 Power regulator 4 AC power supply 5,5-1 Temperature regulator 8 Drive object selection part 11 CT
12 Current detector 13, 13-1 Current limiter

Claims (13)

A plurality of loads are connected between the plurality of first power lines and the plurality of second power lines, and the plurality of first power lines are connected to a power source via a plurality of first opening / closing means, respectively. On the other hand, the plurality of second power lines are connected to the power source via a plurality of second opening / closing means, respectively, and the plurality of first power lines and the plurality of second power lines are virtually connected to each other. When arranged in parallel in the horizontal direction and the vertical direction, one end of each of the plurality of loads is connected to the first power line and the other end is connected to the second power line at a portion where both power lines intersect. A controller for controlling the amount of opening and closing of the first and second opening / closing means connected to adjust the power supplied to the plurality of loads to drive the plurality of loads;
A drive control means for selecting a load to be driven and calculating an operation amount for controlling an opening / closing amount of the first and second opening / closing means corresponding to the selected load;
Based on the output of a current sensor that detects the current flowing through the power line between the power source and the load, the current that limits the operation amount of the operation amount calculation means when the load current value flowing through the load exceeds the limit value And a control unit.   The control device according to claim 1, wherein the current limiting unit acquires the load current value based on an output of the current sensor in accordance with a timing for selecting a load to be driven.   The control device according to claim 1, wherein the drive control unit selects and drives one load among the plurality of loads in order. A plurality of loads are connected between the plurality of first power lines and the plurality of second power lines, and the plurality of first power lines are connected to a power source via a plurality of first opening / closing means, respectively. On the other hand, the plurality of second power lines are connected to the power source via a plurality of second opening / closing means, respectively, and the plurality of first power lines and the plurality of second power lines are virtually connected to each other. When arranged in parallel in the horizontal direction and the vertical direction, one end of each of the plurality of loads is connected to the first power line and the other end is connected to the second power line at a portion where both power lines intersect. A controller for controlling the amount of opening and closing of the first and second opening / closing means connected to adjust the power supplied to the plurality of loads to drive the plurality of loads;
A drive control means for selecting a load to be driven and calculating an operation amount for controlling an opening / closing amount of the first and second opening / closing means corresponding to the selected load;
Based on the operation amount and the driving state of the plurality of loads, a load current flowing through the load is estimated, and when the estimated load current value exceeds a limit value, a current limit that limits the operation amount of the drive control unit And a control device.   The control device according to claim 4, wherein the current limiting unit estimates a load current based on a resistance value corresponding to the operation amount and a driving state of the plurality of loads.   The control device according to claim 4, wherein the current limiting unit limits an operation amount corresponding to a plurality of loads that are selected and driven at the same rate.   The control device according to claim 4, wherein the current limiting unit limits the operation amount corresponding to the plurality of loads that are selected and driven in order from the largest absolute value of the deviation between the control amount and the target value. . The plurality of loads heat a control target,
The control device according to claim 4, wherein the current limiting unit limits the operation amounts corresponding to the plurality of loads that are selected and driven in order from the largest control amount-target value. The plurality of loads cool a control target,
6. The control device according to claim 4, wherein the current limiting unit limits the operation amount corresponding to the plurality of loads that are selected and driven in order from the smallest control amount-target value.   The control device according to claim 4, wherein the current limiting unit limits the operation amounts corresponding to the plurality of loads selected and driven in order from the smallest absolute value.   The control device according to any one of claims 1 to 10, further comprising an overcurrent state notifying unit that notifies when the load current value exceeds the limit value by the current limiting unit. One end of each of the plurality of loads is connected to a power source via a common power line, and each other end is connected to the power source via a plurality of opening / closing means, respectively, to adjust the power supplied to the plurality of loads. A control device for controlling the opening / closing amounts of the plurality of opening / closing means to drive the plurality of loads,
A drive control unit that selects a load to be driven and calculates an operation amount for controlling an opening / closing amount of the plurality of opening / closing units corresponding to the selected load;
Based on the output of a current sensor that detects the current flowing through the power line between the power source and the load, the current that limits the operation amount of the operation amount calculation means when the load current value flowing through the load exceeds the limit value And a control unit. One end of each of the plurality of loads is connected to a power source via a common power line, and each other end is connected to the power source via a plurality of opening / closing means, respectively, to adjust the power supplied to the plurality of loads. A control device for controlling the opening / closing amounts of the plurality of opening / closing means to drive the plurality of loads,
A drive control unit that selects a load to be driven and calculates an operation amount for controlling an opening / closing amount of the plurality of opening / closing units corresponding to the selected load;
A current limit that limits the amount of operation of the drive control means when a load current is estimated based on the operation amount and a driving state of the plurality of loads, and a load current value flowing through the estimated load exceeds a limit value And a control device.

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