TWI558087B - Motor control device (2) - Google Patents

Description

Motor control unit (2) Field of invention

The present invention relates to a motor control device having a power monitoring function.

Background of the invention

In recent years, there has been a need to more precisely manage the amount of power consumed in the plant in a production plant. Therefore, the amount of power consumed by the work machine installed in the production plant is individually monitored. For example, in an electric injection molding machine or a work machine, in order to grasp the amount of consumed electric power of the machine, a motor control device that controls the operation of the machine is provided with a power monitoring function.

A motor control device used in an electric injection molding machine or the like generally has a rectifier that rectifies an alternating current and a plurality of inverters that drive the motor. The method of monitoring the amount of consumed electric power in the motor control device is, for example, the following four methods of the first to fourth.

First, the first method is a method in which a motor controller is provided with a power meter, and the power meter is used to grasp the amount of power consumed by the working machine.

Next, as disclosed in Patent Document 1 below, the second method calculates the power consumption of the motor, the loss power of the amplifier for driving the motor, and the fixed power consumption of the machine tool by calculation, and integrates each of the obtained electric powers with time. And master the method of the amount of electricity consumed by the working machinery.

According to the third method, as disclosed in the following Patent Document 2, the voltage value and the current value between the rectifier and the converter are detected, and the voltage is detected based on the detected voltage. The method of integrating the electric power calculated by the value and the current value with time, thereby grasping the amount of electric power consumed by the working machine.

Finally, the fourth method detects the voltage value and the current value between the three-phase AC power source side and the PWM rectifier as described in Patent Document 3 below, and calculates the consumption power and regeneration from the detected voltage value and current value ( Regenerative) The method of controlling the amount of electricity consumed by a working machine.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2010-115063

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2002-192588

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2010-110936

Summary of invention

However, since the first method requires an additional power meter, the number of parts and the cost of the components constituting the motor control device are increased.

In the case of the second method, in order to obtain electric power such as the power consumption of the motor and the loss power of the amplifier, it is necessary to obtain and store a plurality of parameters such as the motor torque constant, the motor coil resistance value, and the amplifier power loss coefficient. Further, when a plurality of converters are connected to the rectifier and a plurality of types of motors connected to the converter are used, it is necessary to separately determine and memorize individual parameters in accordance with each motor. On the other hand, since the iron loss or mechanical damage of the motor is not considered, it is difficult to say that the detection accuracy of the power consumption is high.

In the case of the third method, it is required to detect the rectifier and the conversion A detector for the voltage and current values between the devices. In general, a detector for detecting current is not provided in a rectifier that is only rectified. Therefore, since the detector for detecting the current must be separately provided, the number of parts and the cost of the parts constituting the motor control device are increased.

In the case of the fourth method, the general 120° power supply is regenerated. In order to reduce the cost of the flow device, a detector for detecting a three-phase AC voltage is not provided. Therefore, since it is necessary to additionally provide a detector for detecting a three-phase AC voltage, the number of parts and the cost of the components constituting the motor control device are increased.

The present invention has been made to solve the conventional problems as described above. The purpose of the present invention is to provide a motor control device having a power monitoring function, which does not require the use of a plurality of parameters such as a motor constant, and does not require a special detector for calculating power, and can be utilized in a 120° power supply regenerative rectifier. An existing detector is provided to control the rectifier to monitor the power consumption.

A motor control device according to the present invention for solving the above problems includes a rectifier unit connected to a multi-phase power supply and a converter unit connected to the motor, and the rectifier unit and the converter unit cooperate to control power operation and regeneration of the motor. Motor control unit.

The motor control device has a phase detecting circuit, a selector circuit, The averaging circuit, the coefficient multiplication circuit, the power calculation circuit, and the integrated power circuit. The phase detecting circuit, the selector circuit, and the averaging circuit use an existing circuit provided to control the power operation and regeneration of the rectifier.

Phase detection circuit detects multiphase AC voltage of multiphase power supply Phase. The selector circuit converts the alternating current into a specific phase from the phase detected by the phase detecting circuit to convert it into a direct current. The averaging circuit averages the DC current converted by the selector circuit to obtain an average DC current. The average DC current can be obtained from the AC current of a specific phase selected based on the phase of the multi-phase AC voltage by the operation of the selector circuit and the averaging circuit.

The coefficient multiplication circuit multiplies the coefficient by the averaging circuit Average DC current. The power calculation circuit calculates the power by multiplying the average DC current obtained by multiplying the coefficient by the coefficient multiplication circuit by the DC voltage on the load side of the rectifier unit. The integrated power circuit integrates the power calculated by the power calculation circuit with time to calculate the integrated power.

According to the present invention having the above configuration, the existing phase detecting circuit, the selector circuit, and the averaging circuit can be used to obtain the average DC current supplied from the multi-phase AC power source, and the obtained average DC current and the rectifier unit can be used. The integrated voltage is obtained by the DC voltage on the load side.

Therefore, it is possible to monitor the power consumption by using a plurality of parameters such as a motor constant and without providing a special detector for calculating the power, and using an existing detector provided to control the rectifier.

Simple illustration

Fig. 1 is a block diagram of a motor control device of the embodiment.

2(A) to (F) are waveform diagrams for explaining the operation of the motor control device shown in Fig. 1.

3(A) to (E) are for explaining the movement of the motor control device shown in Fig. 1. Waveforms made.

Detailed description of the preferred embodiment Form for implementing the invention

Hereinafter, a motor control device according to the embodiment will be described. Fig. 1 is a block diagram of a motor control device of the embodiment.

[Composition of motor control device]

The motor control device 100 includes the reactors 10R, 10S, and 10T, the rectifier unit 20, the capacitor 25, and the converter unit 30 in order to supply electric power to the motor 300.

The reactors 10R, 10S, and 10T are connected to the three-phase power source 200, respectively. The power lines of the three-phase power lines R, S, and T of the rectifier unit 20 are connected in series between the three-phase power source 200 and the rectifier unit 20. The reactors 10R, 10S, and 10T can adjust the currents of the respective power supply lines that respectively flow through the three-phase power lines R, S, and T.

The rectifier unit 20 can change the alternating current from the three-phase power supply 200 Switch to DC. The rectifier unit 20 is constructed by bridging six semiconductor switching elements. The semiconductor switching element is composed of an insulating gate bipolar transistor 20A called an IGBT and a diode 20D. The diode 20D is connected between the collector and the emitter of the insulating gate bipolar transistor 20A. Each of the diodes 20D is connected in such a manner that the three-phase AC full-wave is rectified into a direct current when the power of the motor 300 is operated, but no regenerative current flows. In addition, the semiconductor switching element can also be used in the IGBT with an IPM with a protection circuit instead of the IGBT.

Capacitor 25 uses a large capacity electrolytic capacitor to make the rectifier The DC current output by unit 20 is smoothed.

The converter unit 30 changes the direct current output from the rectifier unit 20 It is supplied to the motor 300 instead of alternating current. Like the rectifier unit 20, the converter unit 30 is constructed by bridging six semiconductor switching elements. The semiconductor switching element is composed of an insulating gate bipolar transistor 30A called an IGBT and a diode 30D. The diode 30D is connected between the collector-emitter of the insulating gate bipolar transistor 30A. Further, each of the diodes 30D is connected in such a manner that the alternating current generated by the motor 300 can be rectified to a direct current when the motor 300 is regenerated.

The motor control device 100 is operated when the power of the motor 300 is running. When you are alive, you will generally behave as follows.

When the motor 300 is powered, the three-phase power supply 200 The supplied alternating current is temporarily converted into a direct current by the rectifier unit 20, and the capacitor 25 becomes a nearly completely direct current. Further, the direct current is converted into an alternating current of a desired frequency and voltage by the converter unit 30, and the motor 300 is powered by the alternating current.

On the other hand, when the current generated by the motor 300 is regenerated At this time, the alternating current generated by the motor 300 is converted into a direct current by the converter unit 30. Further, the direct current is converted into a commercial frequency and a voltage alternating current by the rectifier unit 20, and is reproduced toward the three-phase power supply 200.

Further, in the present embodiment, the rectifier unit 20 is included The six semiconductor switching elements are turned on in the 120° conduction mode, whereby the current generated by the motor 300 is regenerated.

The motor control device 100 controls the rectifier unit 20 and converts Switching of the insulated gate bipolar transistors 20A, 30A of the unit 30 (switching) to adjust the current during the regeneration of the motor 300 and during the power running.

Motor control device 100 for controlling insulated gate bipolar transistors The switches of 20A and 30A are provided with a phase detecting circuit 35, a current selection signal generating circuit 40, current detectors 45R and 45S, a selector circuit 50, an edge detecting circuit 55, an averaging circuit 60, a polarity determining circuit 65, and a stop signal generating. The circuit 70, the power supply voltage peak detecting circuit 75, the regeneration start detecting circuit 80, and the gate signal generating circuit 85 are provided.

The phase detecting circuit 35 detects application to the three-phase power lines R, S, T The phase of the three-phase AC voltage is outputted by a phase signal S4 corresponding to a change in the phase of the three-phase AC voltage.

The current selection signal generating circuit 40 is based on the phase detecting circuit 35 The output phase signal S4 is used to create a current selection signal S3. The current selection signal S3 is used to select a signal of a specific phase of the alternating current from the three-phase AC current.

The current detectors 45R and 45S detect the flow through the three-phase power line R, The two-phase AC current of S. The current flowing through the T phase is obtained from an alternating current of two phases by calculation.

The selector circuit 50 creates the circuit 40 based on the current selection signal. The generated current selection signal S3 is selected from the three-phase alternating currents detected by the current detectors 45R and 45S and calculated by calculation, and the R phase, the S phase, the T phase, the -R phase, the -S phase, and - are selected. Phase T. Therefore, the selection of the alternating current by the selector circuit 50 is equivalent to the AC-DC conversion of the alternating current supplied by the three-phase power supply 200. Therefore, the alternating current can be converted into a direct current by the simple configuration of the selector circuit 50.

The edge detecting circuit 55 detects the edge of the current selection signal S3, borrowing The timing signal is outputted by the detection of the edge. In the present embodiment, the edge of the current selection signal S3 is detected, but the edge of the phase signal S4 outputted by the phase detecting circuit 35 may be detected to output a timing signal.

The averaging circuit 60 is based on the timing of the output of the edge detecting circuit 55. The signal is averaged by the current value selected by the selector circuit 50 to obtain an average DC current. Therefore, the averaging circuit 60 averages the alternating currents of the R phase, the S phase, the T phase, the -R phase, the -S phase, and the -T phase.

The phase detecting circuit 35 and the current selection signal are used as circuit 40. The current detectors 45R and 45S, the selector circuit 50, the edge detecting circuit 55, and the averaging circuit 60 are circuits provided in the motor control device 100 for controlling the rectifier.

The polarity determination circuit 65 is output by the averaging circuit 60. Whether or not the average DC current value becomes 0 or whether the polarity of the average DC current has changed from + to - or from - to + determines whether the motor 300 has changed from power running to regeneration and from regeneration to power running.

If the determination of the polarity determination circuit 65 indicates that it has changed from regeneration to In the power running, the stop signal generating circuit 70 outputs the stop signal S2.

The power supply voltage peak detecting circuit 75 will be applied to the three-phase power line The three-phase AC voltages of R, S, and T are full-wave rectified, and the peak value of the power supply voltage after full-wave rectification is detected.

The regeneration start detecting circuit 80 compares the output of the rectifier unit 20 The DC voltage and the peak value of the full-wave rectified power supply voltage detected by the power supply voltage peak detecting circuit 75. The regeneration start detection circuit 80 is in the rectifier single When the DC voltage output from the element 20 is higher than the peak value of the full-wave rectified power supply voltage by about 15 V, it is determined that the DC voltage has entered the regenerative state, and the regeneration start signal S1 is output.

The gate signal generating circuit 85 outputs the gate signal S5 to the insulating gate bipolar transistor 20A constituting the rectifier unit 20 based on the phase signal S4 which the phase detecting circuit 35 has output. Further, the gate signal generating circuit 85 outputs the gate signal S5 to the insulating gate bipolar transistor 20A based on the regeneration start signal S1 output from the regeneration start detecting circuit 80. Further, the gate signal generating circuit 85 stops the output of the gate signal S5 based on the stop signal S2 that the stop signal generating circuit 70 has output.

The motor control device 100 operates the rectifier unit 20 in the AC-DC conversion mode when the motor 300 performs the power running. On the other hand, when the motor 300 is in the regenerative state, the motor control device 100 causes the rectifier unit 20 to operate in the DC-AC conversion mode.

The regeneration state is detected by the regeneration start detecting circuit 80. When it is in the regenerative state, the gate signal generating circuit 85 outputs the gate signal S5 to the rectifier unit 20. The rectifier unit 20 is controlled by the gate signal S5, and the insulating gate bipolar transistor 20A is energized only by the 120° interval by the power supply phase timing. Power regeneration control called 120° energization is performed. The generated electric power of the motor 300 is regenerated by the three-phase power supply 200 by the power regeneration control.

Then, when the motor 300 is changed from the regenerative state to the power running state (including the completion of the regenerative state), the motor control device 100 again causes the rectifier unit 20 to operate in the AC-DC conversion mode. The power running state is detected by the polarity determining circuit 65. Because when it is detected that it has become moving In the force operation state, the stop signal generating circuit 70 outputs the stop signal S2. Therefore, the slave gate signal generating circuit 85 does not output the gate signal S5, and stops the power source regeneration.

The motor control device 100 includes a coefficient multiplication circuit 110, a power calculation circuit 120, a filter circuit 130, and an integrated power circuit 140 in order to detect the power consumption of the motor control device 100 and the motor 300.

The coefficient multiplication circuit 110 multiplies the set coefficient by the DC current averaged by the averaging circuit 60, and estimates the DC current value output from the rectifier 20. The coefficient set in the coefficient multiplying circuit 110 is a value different from that at the time of power running of the motor 300. The coefficient during the power running and the regeneration is measured in advance in the actual use state, and the measured value is set. In addition, since the loss of the rectifier 20 is proportional to the magnitude of the direct current, the coefficient can be set in advance foreseeing the loss of the rectifier 20, so that a more accurate consumption power calculation can be performed.

The power calculation circuit 120 multiplies the DC current estimated by the coefficient multiplication circuit 110 by the DC voltage of the rectifier 20 to calculate the power.

The filter circuit 130 is a low-pass filter that cuts off high-frequency components of the power waveform calculated by the power calculation circuit 120.

The integrated power circuit 140 calculates an integrated power amount that totals the amount of electric power that the motor control device 100 supplies to the motor 300 by integrating the power waveform that has passed through the filter circuit 130 and is free of noise, and the motor 300 The amount of electric power to be regenerated, and the amount of electric power that the motor control device 100 itself has consumed. The calculated integrated power amount is output to an external device.

In addition, the three-phase power supply voltage of the three-phase power supply 200 can also be performed. The average value of the power supply voltage is calculated by full-wave rectification, the coefficient is multiplied by the average value of the power supply voltage, and the coefficient is multiplied by the averaged DC current, and the average power is calculated by the filter circuit 130.

Further, the reactors 10R, 10S, and 10T may be disposed on the power source side than the current detectors 45R and 45S. In the present embodiment, one converter unit 30 is connected to one rectifier unit 20. However, even if a plurality of converter units 30 are connected to one rectifier unit 20, power consumption can be calculated.

The motor control device 100 detects the current flowing through the three-phase power supply 200, multiplies the coefficient by the detected current, estimates the DC current value output from the rectifier unit 20, and multiplies the output voltage of the rectifier unit 20 by the estimated DC current value. And calculate the average power. Then, the calculated average power is integrated over time to obtain the correct power consumption.

Further, each of the circuits constituting the motor control device 100 of the present embodiment may be configured as a hard body or may be formed inside a microcomputer or the like using a soft body.

[Operation of Motor Control Unit]

Next, a specific operation of the motor control device 100 will be described with reference to FIGS. 2 and 3. 2 and 3 are waveform diagrams for explaining the operation of the motor control device shown in Fig. 1.

The waveform shown in FIG. 2(A) is a three-phase power supply 200 applied to the power supply voltages VR, VS, and VT of the respective power supply lines of the three-phase power supply lines R, S, and T, respectively. The power supply voltages VR, VS, and VT have the same voltage waveform and each phase differs by 120°.

Fig. 2(B) shows the phase signal S4 output from the phase detecting circuit 35 of Fig. 1. The phase detecting circuit 35 compares the power supply voltages VR, VS, and VT of the three-phase power supply lines R, S, and T, and outputs phase signals PR1, PS1, PT1, PR2, PS2, and PT2.

Comparing the power supply voltage VR, the power supply voltage VS, or the power supply voltage VT, when the power supply voltage VR is larger than the power supply voltage VS or the power supply voltage VT, the phase signal PR1 is HI, when the power supply voltage VR is lower than the power supply voltage VS, or the power supply voltage VT The phase signal PR1 is LOW. When the power supply voltage VS is larger than the power supply voltage VR or the power supply voltage VT, the phase signal PS1 is HI, and when the power supply voltage VS is smaller than the power supply voltage VR or the power supply voltage VT, the phase signal PS1 is LOW. When the power supply voltage VT is larger than the power supply voltage VR or the power supply voltage VS, the phase signal PT1 is HI. When the power supply voltage VT is lower than the power supply voltage VR or the power supply voltage VS, the phase signal PT1 is LOW.

Comparing the power supply voltage VR, the power supply voltage VS, or the power supply voltage VT, when the power supply voltage VR is lower than the power supply voltage VS or the power supply voltage VT, the phase signal PR2 is HI, when the power supply voltage VR is greater than the power supply voltage VS or the power supply voltage VT The phase signal PR2 is LOW. When the power supply voltage VS is smaller than the power supply voltage VR or the power supply voltage VT, the phase signal PS2 is HI, and when the power supply voltage VS is larger than the power supply voltage VR or the power supply voltage VT, the phase signal PS2 is LOW. When the power supply voltage VT is lower than the power supply voltage VR or the power supply voltage VS, the phase signal PT2 is HI, and when the power supply voltage VT is larger than the power supply voltage VR or the power supply voltage VS, the phase signal PT2 is LOW.

Therefore, the phase signals PR1, PS1, and PT1 indicate intervals in which the power supply voltage of each phase is larger than the voltages of the other phases, and the phase signals PR2, PS2, and PT2. A section in which the power supply voltage of each phase is larger on the negative side than the voltage of the other phase.

When the power of the motor 300 is running, the three-phase AC power from the three-phase power source 200 is rectified by the freewheel diode 20D of the rectifier unit 20, and the rectified DC power is output to the capacitor 25 and the converter unit 30. The motor 300 is driven by conversion to alternating current power. When the motor 300 is accelerated, the DC voltage output from the rectifier unit 20 is slowly lowered as shown in Fig. 3(A), and the average DC current output from the averaging circuit 60 is gradually increased. Then, when the motor 300 is in the constant speed state, the value of the average DC current becomes constant. The action for obtaining the average DC current value will be described later. When the power of the motor 300 is being operated, the brake signal generating circuit 85 is stopped.

When the motor 300 is regenerated, the DC voltage output from the rectifier unit 20 gradually increases as shown in Fig. 3(A). The DC voltage output from the rectifier unit 20 is higher than the peak value of the power supply voltage detected by the power supply voltage peak detecting circuit 75. The regeneration start detecting circuit 80 outputs a regeneration start signal S1.

When the reproduction start signal S1 is input to the gate signal creation circuit 85, the gate signal creation circuit 85 creates the gate signal S5 based on the phase signals PR1, PS1, PT1, PR2, PS2, and PT2. The generated gate signal S5 is output to the rectifier unit 20.

The six transistors 20A of the rectifier unit 20 are turned on in the 120° conduction mode in accordance with the gate signal S5, and the regenerative electric power is regenerated in the three-phase power supply 200.

Fig. 2(C) shows the contents of the current selection signal S3 created by the current selection signal creation circuit 40. In Fig. 2(C), the expressions of S, R, T, and -S, -R, and -T refer to the electric power respectively selected to flow through the three-phase power lines R, S, and T. The meaning of IR, IS, IT and its inverted signals.

The currents IR, IS, and IT flowing through the phases of the three-phase power lines R, S, and T as shown in Fig. 2(D) are operated by the rectifier unit 20 to conduct currents of the respective phases by the 120° conduction mode. Since it is regenerated on the side of the three-phase power supply 200, the currents IR, IS, and IT are distributed at 120 degrees apart.

For example, the current selection signal "-S" of Fig. 2(C) indicates that the current IS flowing through the three-phase power line S is selected, and the selector circuit 50 outputs the polarity inversion signal of the current. Further, the current selection signal "R" of Fig. 2(C) indicates that the current IR flowing through the three-phase power supply line R is selected, and the selector circuit 50 directly outputs the current. The current selection signal "-T" of Fig. 2(C) indicates that the current IT flowing through the three-phase power supply line T is selected, and the selector circuit 50 outputs the polarity inversion signal of the current. The items indicated by the current selection signals "S", "-R", and "T" are subject to the above-mentioned current selection signals "-S", "R", and "-T".

2(E) shows the current selection output in which the current selected by the selector circuit 50 is arranged in time series. When the current of the three-phase share is selected by the selector circuit 50, the averaging circuit 60 averages the currents of the three-phase parts and outputs them.

2(F) is a waveform of the average DC current output from the averaging circuit 60. The averaging circuit 60 performs averaging processing according to the end of the input of the current value of each three-phase component, and the value of the average DC current changes stepwise in response to the change in the current value.

Fig. 3(B) shows the change in the average DC current when the length of the time axis is shortened as compared with Fig. 2(F). Since the current flows from the motor 300 side to the three-phase power source 200 side during the regeneration period, in the power running state, for example, When the current selection signal S3 is generated to output the value of the average direct current of the positive polarity, the average DC current value at the time of regeneration becomes negative. When the rotational speed of the motor 300 is lowered and the regenerative electric power is reduced, the value of the average direct current is correspondingly lowered.

Theoretically, when the value of the average DC current becomes "0", it can be determined that the regeneration has ended. However, the current change in the vicinity of the average DC current value of "0" becomes unstable, and it is easy to make a misjudgment. Therefore, in the present embodiment, whether or not the power has been changed from the regeneration to the power operation is determined by the polarity determination circuit 65 that the value of the average DC current exceeds a predetermined value and changes to zero. At a certain time, the average DC current value has become 0, or its polarity has changed.

Therefore, there is less possibility of erroneous determination in the present embodiment. When the polarity determination circuit 65 detects that the value of the average direct current becomes 0 or its polarity is inverted, the stop signal generating circuit 70 generates the stop signal S2.

When the stop signal S2 is output from the stop signal generating circuit 70, the brake signal generating circuit 85 stops the operation of the gate signal, and the six transistors 20A of the rectifier unit 20 are turned off. Thereafter, when the converter unit 30 operates, DC power is output by the rectifier circuit constituted by the six diodes 20D of the rectifier unit 20.

3(C) is a DC current estimated value of the rectifier unit 20 obtained by multiplying the coefficient previously set in the coefficient multiplying circuit 110 by the average DC current output from the averaging circuit 60. When the power of the motor 300 is running, the rising angle of the DC current estimated value of FIG. 3(C) is larger than the rising angle of the average DC current of FIG. 3(B). On the other hand, when the motor 300 is regenerated, Figure 3(B) The rising angle of the average DC current is substantially the same as the rising angle of the DC current estimated value of FIG. 3(C). This is because the coefficient set in the coefficient multiplying circuit 110 is different between the power running of the motor 300 and the time of regeneration.

FIG. 3(D) is a waveform of the average power obtained after passing through the filter circuit 130. FIG. 3(E) is a waveform of the amount of electric power obtained by time-integrating the average electric power in the integrated electric power circuit 140. As can be seen from Fig. 3(E), when the power of the motor 300 is operated, the amount of electric power is increased, and the amount of electric power during regeneration is reduced.

By monitoring the amount of electric power calculated by the integrated power circuit 140, the power consumption of the motor 300 including the motor control device 100 can be easily and accurately obtained at low cost. It is possible to easily grasp the amount of electric power because it is not necessary to use a plurality of parameters such as a motor constant; and it is low-cost, because it is not provided with a special detector for calculating electric power, but is provided for controlling the rectifier. The existing detector is the reason.

As described above, according to the motor control device of the present embodiment, the power consumption can be easily and accurately grasped at a low cost.

10R, 10S, 10T‧‧‧ reactor

20‧‧‧Rectifier unit

20A‧‧‧Insulated gate bipolar transistor

20D‧‧‧ diode

25‧‧‧ capacitor

30‧‧‧ converter unit

30A‧‧‧Insulated gate bipolar transistor

30D‧‧‧ diode

35‧‧‧ phase detection circuit

40‧‧‧ Current selection signal making circuit

45R, 45S‧‧‧ current detector

50‧‧‧Selector Circuit

55‧‧‧Edge detection circuit

60‧‧‧Averaging circuit

65‧‧‧Polarity determination circuit

70‧‧‧ stop signal generation circuit

75‧‧‧Power supply voltage peak detection circuit

80‧‧‧Regeneration start detection circuit

85‧‧‧ brake signal making circuit

100‧‧‧Motor control unit

110‧‧‧ coefficient multiplication circuit

120‧‧‧Power calculation circuit

130‧‧‧Filter circuit

140‧‧‧Integrated power circuit

200‧‧‧Three-phase power supply

300‧‧‧Motor

R, S, T‧‧‧ three-phase power cord

S1‧‧‧ regeneration start signal

S2‧‧‧ stop signal

S3‧‧‧ current selection signal

S4‧‧‧ phase signal

S5‧‧‧ gate signal

Fig. 1 is a block diagram of a motor control device of the embodiment.

2(A) to (F) are waveform diagrams for explaining the operation of the motor control device shown in Fig. 1.

3(A) to (E) are waveform diagrams for explaining the operation of the motor control device shown in Fig. 1.

10R, 10S, 10T‧‧‧ reactor

20‧‧‧Rectifier unit

20A‧‧‧Insulated gate bipolar transistor

20D‧‧‧ diode

25‧‧‧ capacitor

30‧‧‧ converter unit

30A‧‧‧Insulated gate bipolar transistor

30D‧‧‧ diode

35‧‧‧ phase detection circuit

40‧‧‧ Current selection signal making circuit

45R, 45S‧‧‧ current detector

50‧‧‧Selector Circuit

55‧‧‧Edge detection circuit

60‧‧‧Averaging circuit

65‧‧‧Polarity determination circuit

70‧‧‧ stop signal generation circuit

75‧‧‧Power supply voltage peak detection circuit

80‧‧‧Regeneration start detection circuit

85‧‧‧ brake signal making circuit

100‧‧‧Motor control unit

110‧‧‧ coefficient multiplication circuit

120‧‧‧Power calculation circuit

130‧‧‧Filter circuit

140‧‧‧Integrated power circuit

200‧‧‧Three-phase power supply

300‧‧‧Motor

R, S, T‧‧‧ three-phase power cord

Claims (7)

A motor control device includes a rectifier unit connected to a multi-phase power source and an inverter unit connected to the motor, and the rectifier unit and the converter unit cooperate to control the power operation and regeneration of the motor. The invention is characterized in that: a phase detecting circuit detects a phase of the multi-phase AC voltage of the multi-phase power source; and a selector circuit selects a phase detected by the phase detecting circuit, selects an alternating current of a specific phase, and converts into a direct current. The averaging circuit is obtained by averaging the DC current converted by the selector circuit to obtain an average DC current; the coefficient multiplication circuit multiplying the coefficient by the average DC current obtained by the averaging circuit The power calculation circuit calculates the power by multiplying the average DC current obtained by multiplying the coefficient by the coefficient multiplication circuit by the DC voltage on the load side of the rectifier unit; and integrating the power circuit, and calculating the power circuit The power calculated by the circuit is integrated by time, and the integrated power is calculated, and the phase is Sensing circuit, the selection circuit, the line averaging circuit for controlling the operation and the regenerative power of the motor provided in the existing circuit. The motor control device of claim 1, wherein the multi-phase power source is a three-phase power source, and the motor control device further has two current detectors for detecting an alternating current flowing in two phases in three phases, and Circulation The alternating current of the other phase in the three phases described above is obtained by calculation. A motor control device according to claim 2, wherein the selection of the alternating current by the selector circuit is equivalent to the alternating current-direct current conversion of the alternating current supplied from the multiphase power source. The motor control device according to any one of claims 1 to 3, wherein a current selection signal generating circuit is provided between the phase detecting circuit and the selector circuit, and the current selection signal is formed in a circuit according to the phase The phase signal outputted by the detection circuit outputs a current selection signal for causing the selector circuit to select an alternating current of a specific phase. The motor control device of claim 4, wherein between the current selection signal generating circuit and the averaging circuit, an edge detecting circuit is provided, wherein the edge detecting circuit detects a current outputted from the current selection signal The edge of the signal is selected, and a timing signal for averaging the DC current is output to the aforementioned averaging circuit by edge detection. The motor control device according to any one of claims 1 to 3, wherein the coefficient used in the coefficient multiplying circuit is different between the power operation of the motor and the regeneration. The motor control device according to any one of claims 1 to 3, wherein the rectifier unit is powered by the motor by turning on a semiconductor switching element provided in the rectifier unit in a 120° conduction mode. The power is regenerated from the aforementioned multi-phase power source.