JP5050387B2 - Motor control device - Google Patents

Description

  The present invention relates to a control device for an AC motor (referred to as an AC motor in this specification).

The generated torque of the permanent magnet type synchronous motor is expressed by the outer product of the vector of magnetic flux generated in the motor and the vector of current flowing in the winding.
The magnetic flux generated in the motor is a magnetic flux generated by a permanent magnet (referred to as “magnet magnetic flux” in this specification) and a magnetic flux generated by causing the winding and the iron core of the winding to act as an electromagnet by passing a current through the winding. In the specification, it is referred to as “current magnetic flux”). Since the magnetic flux and the generation ratio of current flux to current (referred to as inductance in this specification) are parameters specific to the motor, current feedback control that feeds back the current detection value to the current target value corresponding to the torque target value System may be configured and motor torque may be controlled.

However, it is known that the magnetic flux of the magnet changes depending on the temperature of the magnet. Even if the current target value corresponding to the torque target value is set, the motor torque changes as the magnet temperature changes, and the torque target value The motor torque is not as expected.
Also, when the temperature of the current detector used for current feedback control changes, the detection characteristics of the current detector with respect to the actual flowing current, that is, the offset and slope change, so the current target value does not change. The actual current due to the feedback control changes, and the motor torque as the torque target value cannot be obtained.

  In order to solve such problems, a method of controlling a motor torque by constructing a torque feedback control system that actually detects a motor torque using a torque detector and feeds back a torque detection value to a torque target value. However, there are problems such as an increase in cost due to the use of the torque detector and a mounting space for the torque detector.

  Therefore, a device (see Patent Documents 1 to 3) in which the amount of change in the magnetic flux is estimated to correct the current target value so that the motor torque matches the torque target value, or the current detection value during one electrical angle cycle. There is known an apparatus (see Patent Document 4) in which an average value is set to 0 point of a current detector, and offset fluctuation due to temperature change of the current detector is suppressed so that motor torque matches a torque target value.

Prior art documents related to the invention of this application include the following.
Japanese Patent Application Laid-Open No. 07-212915 JP 2002-078390 A JP 2000-224812 A JP 05-252785 A

By the way, in the region where the iron core of the motor is magnetically saturated, the magnetic saturation is reduced as much as the magnet magnetic flux is reduced, so that the current magnetic flux easily passes and increases. Conversely, when the magnetic flux increases, the current magnetic flux is increased. Get smaller. In other words, in a magnetically saturated state, when the magnetic flux changes, the inductance also changes, so the current magnetic flux changes. However, since the above-described conventional motor control device does not take this point into consideration, it cannot cope with the motor torque fluctuation caused by the current magnetic flux change.
When the slope of the current detection value with respect to the actual current changes due to the temperature change of the current detector, the amplitude of the fundamental wave component of the current itself changes, so that the average value of the current detection value during one electrical angle cycle is As a result, the temperature variation of the slope of the current detection value with respect to the actual current cannot be detected, and the motor torque variation due to the temperature change of the current detector cannot be handled.

(1) In the present invention, a dq-axis voltage target value for setting a dq-axis current target value according to the torque target value and the motor rotation speed and making the dq-axis current detection value coincide with the dq-axis current target value is calculated. The dq axis voltage target value is converted into a three-phase AC voltage target value in a three-phase AC coordinate system, and a three-phase AC voltage corresponding to the three-phase AC voltage target value is applied to a three-phase synchronous motor for driving. In the apparatus, the torque fluctuation amount of the motor is calculated based on the torque target value, the motor rotation speed, the dq axis voltage target value, the dq axis current detection value, and the winding temperature detection value, and the torque target value is corrected by the torque fluctuation amount. .
(2) Further, in the present invention, a dq-axis voltage target value for setting a dq-axis current target value according to the torque target value and the motor rotation speed and making the dq-axis current detection value coincide with the dq-axis current target value. And the dq-axis voltage target value is converted to a three-phase AC voltage target value in a three-phase AC coordinate system, and a three-phase AC voltage corresponding to the three-phase AC voltage target value is applied to a three-phase synchronous motor for driving. In the motor control device, the amount of change in the current detection value caused by the temperature change of the current detector is calculated based on the torque target value, motor rotation speed, dq axis voltage target value, dq axis current detection value, and winding temperature detection value. The dq-axis current detection value is corrected based on the current detection value change amount.

  According to the present invention, it is possible to suppress motor torque fluctuation caused by temperature changes of the motor magnet and the current detector.

<< First Embodiment of the Invention >>
FIG. 1 is a diagram showing the configuration of the first embodiment. As shown in FIG. 1, the motor control device of the first embodiment is composed of many control blocks and devices having various functions. Each control block is softened by peripheral components such as a microcomputer and a memory. It is realized in the form of wear.

The current / voltage target value generator 1 outputs the corrected torque target value T ^* ′ and current target values id ^* and iq ^* and induced voltage values vd ^* _dcpl and vq ^* _dcpl corresponding to the motor rotation speed N. Specifically, current target values id ^* and iq ^* and induced voltage values vd ^* _dcpl and vq ^* _dcpl corresponding to the torque target value T ^* ′ and the motor rotation speed N are set by motor evaluation experiments, etc. Is stored in a memory (not shown).

FIG. 2 shows an example of the table data. In this embodiment, a data table having an accuracy for setting the motor rotation speed N every 500 rpm, for example, and the torque target value T ^* ′ every 10 Nm, for example, is used. When the motor is controlled, the current torque target value T ^* 'and the motor rotation speed N are used as an index, and the table data is referred to. Using the data around the index (indicated by black circles in the figure), the linear approximation is used to support the index. Current target values id ^* and iq ^* and induced voltage values vd ^* _dcpl and vq ^* _dcpl (indicated by white circles in the figure) are calculated.

The current vector controller 2 detects the current target values id ^* and iq ^* and the induced voltage values vd ^* _dcpl and vq ^* _dcpl input from the current / voltage target value generator 1 and the dq axes input from the coordinate converter 10. Based on the currents id and iq, current vector control processing including current error PI amplification and non-interference control is performed, and dq-axis voltage target values vd ^* and vq ^* are output. The coordinate converter 10 converts the three-phase alternating currents iu and iv in the three-phase alternating current coordinate system detected by the current detectors 6a and 6b into the detected currents id and iq in the rotational orthogonal coordinate system (dq axis coordinate system). .

The coordinate converter 3 converts the voltage target values vd ^* and vq ^* in the dq axis coordinate system into voltage target values vu ^* , vv ^* and vw ^* in the three-phase AC coordinate system. The PWM converter 4 converts the three-phase AC voltage target values vu ^* , vv ^* , vw ^* into power element drive signals Du, Dv, Dw of the inverter 5. The inverter 5 converts the DC power supply of the battery 5a into a three-phase AC voltage Vu, Vv, Vw by a power element (not shown) and applies it to the motor 7 for driving. The position converter 8 detects the electrical angle θ of the rotor of the three-phase synchronous motor 7, and the speed calculator 9 determines the motor rotational speed N (rpm) and the electrical angular speed ω (= 2π ·) based on the change in the motor electrical angle θ. N / 60) (rad / sec) is calculated. The winding temperature detector 14 detects the winding temperature t of the three-phase synchronous motor 7.

The torque fluctuation amount calculation unit 11 includes a reference voltage / winding temperature generator 12 and a torque fluctuation amount estimator 13. The reference voltage / winding temperature generator 12 outputs reference voltage values vd_ref and vq_ref corresponding to the torque target value T ^* and the motor rotation speed N and the reference winding temperature tref. Specifically, reference voltage values vd_ref, vq_ref and reference winding temperature tref corresponding to torque target value T ^* and motor rotation speed N are set by a motor evaluation experiment or the like, and stored in advance in a memory (not shown) as table data. Keep it.

Here, the reference voltage values vd_ref and vq_ref are voltage target values vd ^* and vq ^* when the motor 7 generates a torque equal to the torque target value T ^* , and are previously measured by experiments. Similarly, the reference winding temperature tref is the winding temperature t when the motor 7 is generating a torque equal to the torque target value T ^* , and is previously measured by experiment.

At the time of motor control, reference is made to the table data using the current torque target value T ^* and the motor rotation speed N as an index, and reference voltage values vd_ref and vq_ref corresponding to the index are obtained by linear approximation using the data around the index and the reference winding. The temperature tref is calculated.

The torque fluctuation amount estimator 13 estimates the torque fluctuation amount ΔT based on the reference voltage values vd_ref and vq_ref, the reference winding temperature tref, the voltage target values vd ^* and vq ^* , the detected currents id and iq, and the winding temperature t. The method for estimating the torque fluctuation amount ΔT will be described later in detail. The low-pass filter 16 performs noise reduction processing on the estimated torque fluctuation amount ΔT, and the PI (proportional / integral) amplifier 15 PI-calculates the estimated torque fluctuation amount ΔT after the noise reduction processing. The adder 17 calculates a torque target value T ^{* 'subtracts} the output (estimated torque fluctuation amount [Delta] T) of the PI amplifier 15 from the torque target value T ^*, and outputs it to the current-voltage target value generator 1.

上記（１）、（２）式において、ｖd、ｖqはｄｑ軸入力電圧、Ｒはモーター巻線抵抗、ωはモーター電気角速度（＝２π・Ｎ／６０）（rad／sec）、Ｌd、Ｌqはｄｑ軸インダクタンス、ｉd、ｉqはｄｑ軸電流、φaは磁石磁束、φd、φqはｄｑ軸磁束（磁石磁束と電流磁束の合成磁束）、ｐは極対数である。 << Method 1 of Estimating Torque Fluctuation ΔT >>
Next, a method for estimating the torque fluctuation amount ΔT due to the temperature change of the magnetic flux of the magnet will be described. In general, a voltage equation in a permanent magnet type synchronous motor is expressed by equation (1), and a torque generation equation is expressed by equation (2).

In the above formulas (1) and (2), vd and vq are dq axis input voltages, R is motor winding resistance, ω is motor electrical angular velocity (= 2π · N / 60) (rad / sec), Ld and Lq are dq axis inductance, id and iq are dq axis currents, φa is magnet magnetic flux, φd and φq are dq axis magnetic fluxes (combined magnetic flux of magnet magnetic flux and current magnetic flux), and p is the number of pole pairs.

It is known that when the magnet temperature changes, the magnetic flux φa changes, but when magnetic saturation occurs, the magnitudes of the magnetic fluxes Ld · id and Lq · iq generated by the current also change. Therefore, when the fluctuation amount of the dq-axis input voltages vd and vq and the fluctuation amount of the torque with respect to the change of the magnet magnetic flux and the current magnetic flux are expressed in consideration of the winding resistance change due to the winding temperature change, the following equation is obtained.

この（５）式を（４）式へ代入すると（６）式が得られる。

つまり、入力電圧ｖd、ｖqの変動分Δｖd、Δｖqと巻線抵抗Ｒの変動分ΔＲからトルク変動量ΔＴを推定することができる。 When formula (3) is arranged for dq-axis magnetic fluxes Δφd and Δφq, formula (5) is obtained.

Substituting this equation (5) into equation (4) yields equation (6).

That is, the torque fluctuation amount ΔT can be estimated from the fluctuations Δvd and Δvq of the input voltages vd and vq and the fluctuation ΔR of the winding resistance R.

同様に、巻線抵抗Ｒの変動分ΔＲは、予め実験により測定した、モーター７がトルク目標値Ｔ^＊に等しいトルクを出力しているときの巻線温度（基準温度）ｔrefと、現在の巻線温度ｔから次式により求める。

（８）式において、Ｒo、αoは任意の温度ｔo（通常は２０℃）での抵抗値および抵抗温度係数である。また、巻線抵抗Ｒの変化分ΔＲが推定トルク変動量ΔＴにほとんど影響しない程度に小さい場合はΔＲ＝０として省略しても構わない。 The fluctuations Δvd and Δvq of the input voltages vd and vq are voltage target values (reference voltages) vd_ref and vq_ref when the motor 7 outputs a torque equal to the torque target value T ^* , measured in advance, and the current values. Is obtained from the following voltage target values vd ^* and vq ^* .

Similarly, the variation ΔR of the winding resistance R is measured in advance through experiments, and the winding temperature (reference temperature) tref when the motor 7 outputs a torque equal to the torque target value T ^* and the current winding. It calculates | requires by following Formula from linear temperature t.

In the equation (8), Ro and αo are a resistance value and a resistance temperature coefficient at an arbitrary temperature to (usually 20 ° C.). If the change ΔR in the winding resistance R is small enough to hardly affect the estimated torque fluctuation amount ΔT, ΔR = 0 may be omitted.

また、（６）式は次のように変形できる。

（９）、（１０）式において、Ｒrefは基準巻線抵抗、ｉd_ref、ｉq_refは基準電流、Ｐは推定電力、Ｐrefは基準電力、Ｔは推定トルク、Ｔrefは基準トルクである。基準巻線抵抗Ｒrefは、モーター７がトルク目標値Ｔ^＊に等しいトルクを発生しているときの、巻線抵抗温度ｔrefにおける巻線抵抗Ｒ(t)である。また、基準電流ｉd_ref、ｉq_refは、モーター７がトルク目標値Ｔ^＊に等しいトルクを発生しているときのｄｑ軸電流ｉd、ｉqである。基準トルクＴrefは、モーター７がトルク目標値Ｔ^＊に等しいトルクを発生しているときの推定トルクＴである。さらに、基準電力Ｐrefは、モーター７がトルク目標値Ｔ^＊に等しいトルクを発生しているときの推定電力Ｐである。巻線抵抗Ｒ(t)は次式で算出する。

<< Torque fluctuation estimation method 2 >>
Another method for estimating the torque fluctuation amount ΔT due to the temperature change of the magnet magnetic flux will be described. Equation (5) can be modified as follows.

Further, the expression (6) can be modified as follows.

In equations (9) and (10), Rref is a reference winding resistance, id_ref and iq_ref are reference currents, P is an estimated power, Pref is a reference power, T is an estimated torque, and Tref is a reference torque. The reference winding resistance Rref is the winding resistance R (t) at the winding resistance temperature tref when the motor 7 generates a torque equal to the torque target value T ^* . Reference currents id_ref and iq_ref are dq-axis currents id and iq when the motor 7 is generating torque equal to the torque target value T ^* . The reference torque Tref is an estimated torque T when the motor 7 is generating a torque equal to the torque target value T ^* . Furthermore, the reference power Pref is the estimated power P when the motor 7 is generating a torque equal to the torque target value T ^* . Winding resistance R (t) is calculated by the following equation.

The torque fluctuation amount calculation unit 11A shown in FIG. 3 is obtained from the equation (10), and is used instead of the torque fluctuation amount calculation unit 11 shown in FIG. The torque fluctuation amount calculation unit 11A includes a reference power or reference torque generator 12A and a torque fluctuation amount estimator 13A. The reference power or reference torque generator 12A outputs the reference power Pref or the reference torque Tref corresponding to the torque target value T ^* before correction and the motor rotation speed N.

Specifically, the reference power Pref and the reference torque Tref corresponding to the torque target value T ^* and the motor rotation speed N are set by a motor evaluation experiment or the like, and stored in advance in a memory (not shown) as a data table. When the motor is controlled, the table data is referred to using the current torque target value T ^* and the motor rotation speed N as an index, and the reference power Pref or the reference torque Tref corresponding to the index is obtained by linear approximation using the data around the index. calculate.

  In the torque fluctuation amount estimator 13A, the estimated power P or the estimated torque T is calculated by the equation (10), and the torque fluctuation amount ΔT is estimated from the difference from the reference power Pref or the reference torque Tref.

  According to the estimation method 2 of the torque fluctuation amount ΔT, the number of reference value data tables may be either one of the reference power Pref or the reference torque Tref. Therefore, like the torque fluctuation amount calculation unit 11 shown in FIG. Compared to a configuration that requires three types of data tables of the reference voltages vd_ref and vq_ref and the reference winding temperature tref, the memory capacity and the table reference time can be reduced.

よって、（６）式は次のように変形できる。

<< Method 3 for Estimating Torque Fluctuation ΔT >>
Another method for estimating the torque fluctuation amount ΔT due to the temperature change of the magnet magnetic flux will be described. Since the numerator on the right side of the equation (5) represents the variations Δvd_dcpl and Δvq_dcpl of the induced voltage, the induced voltages vd ^* _dcpl and vq ^* _dcpl which are the outputs of the current / voltage target value generator 1 are used as Can be expressed as

Therefore, equation (6) can be modified as follows.

FIG. 4 shows the configuration of the first embodiment when the torque fluctuation amount ΔT estimation method 3 is used. In FIG. 4, circuits and devices having the same functions as those in FIGS. 1 and 3 are denoted by the same reference numerals, and different points will be mainly described. The current / voltage target value generator 1a outputs induced voltages vd ^* _dcpl and vq ^* _dcpl corresponding to the torque target value T ^* before correction and the motor rotation speed N. Specifically, induced voltages vd ^* _dcpl and vq ^* _dcpl corresponding to the torque target value T ^* and the motor rotational speed N are set by a motor evaluation experiment or the like, and stored in advance in a memory (not shown) as table data. . Then, the table data is referred to using the current torque target value T ^* and the motor rotation speed N as an index during motor control, and induced voltages vd ^* _dcpl, vq ^* _dcpl corresponding to the index by linear approximation using the data around the index. Is calculated.

The torque fluctuation amount calculation unit 11B includes only a torque fluctuation amount estimator 13B. The torque fluctuation amount estimator 13B receives the induced voltages vd ^* _dcpl and vq ^* _dcpl input from the current / voltage target value generator 1a, the detected currents id and iq input from the coordinate converter 10, and the current vector controller 2 Based on the voltage target values vd ^* and vq ^* , the motor electrical angular velocity ω input from the speed calculator 9, and the winding temperature t input from the winding temperature detector 14, the torque fluctuation amount ΔT is estimated by the equation (13). To do.

From equations (12) and (13), as shown in FIG. 4, induced voltages vd ^* _dcpl, vq ^* _dcpl (current / voltage) for the corrected torque target value T ^* ′ used for vector current control and the motor rotational speed N Aside from the output of the target value generator 1), by referring to the table data set and stored in advance, the torque target value T ^* before correction and the induced voltages vd ^* _dcpl, vq ^* _dcpl with respect to the motor rotational speed N (the same sign) Is the reference voltage table of the reference voltage / winding temperature generator 12 shown in FIG. 1 or the reference power or reference torque generator 12A shown in FIG. The torque fluctuation amount ΔT can be estimated without preparing new reference value table data such as data.

  FIG. 5 is a flowchart showing the torque fluctuation suppressing process of the first embodiment. The operation of the first embodiment will be described with reference to this flowchart. When the motor control apparatus of the first embodiment is started, the torque fluctuation suppressing process shown in FIG. 5 is repeatedly executed.

In step 1, a reference parameter for estimating the torque fluctuation amount ΔT is acquired according to the above-described torque fluctuation amount ΔT estimation methods 1 to 3. In the case of the estimation method 1, the reference voltage / winding temperature generator 12 shown in FIG. 1 refers to the data table and the reference voltage values vd_ref and vq_ref corresponding to the current torque target value T ^* and the motor rotational speed N. A reference winding temperature tref is acquired. In the case of the estimation method 2, the reference power or reference torque generator 12A shown in FIG. 3 refers to the data table and determines the reference power Pref or the reference torque Tref corresponding to the current torque target value T ^* and the motor rotational speed N. get. In the case of the estimation method 3, the current / voltage generator 1a shown in FIG. 4 refers to the data table and obtains the induced voltages vd ^* _dcpl and vq ^* _dcpl corresponding to the current torque target value T ^* and the motor rotational speed N. To do.

In the subsequent step 2, current detection values id and iq are obtained from the coordinate converter 10, and voltage target values vd ^* and vq ^* are obtained from the current vector controller 2, respectively. Further, in step 3, the winding temperature t is acquired from the winding temperature detector 14. In step 4, torque fluctuation amount ΔT is calculated according to estimation methods 1 to 3. In the case of the estimation method 1, the torque fluctuation amount estimator 13 shown in FIG. 1 uses the reference voltage values vd_ref and vq_ref, the reference winding temperature tref, the voltage target values vd ^* and vq ^* , the detected currents id and iq, and the winding temperature t. Is used to estimate the torque fluctuation amount ΔT. In the case of the estimation method 2, the torque fluctuation is estimated based on the reference power Pref or the reference torque Tref, the voltage target values vd ^* and vq ^* , the detected currents id and iq, and the winding temperature t by the torque fluctuation amount estimator 13A shown in FIG. The quantity ΔT is estimated. In the case of the estimation method 3, based on the induced voltage vd ^* _dcpl, vq ^* _dcpl, voltage target value vd ^* , vq ^* , detected current id, iq and winding temperature t by the torque fluctuation amount estimator 13B shown in FIG. A torque fluctuation amount ΔT is estimated.

In step 5 after estimating the torque fluctuation amount ΔT, the calculated torque fluctuation amount ΔT is subjected to noise removal processing by the low-pass filter 16 and further subjected to PI calculation amplification processing by the PI (proportional / integration) amplifier 15. Finally, in step 6, the adder 17 by calculating the torque target value T ^{* 'subtracts} the output of PI amplifier 15 from the torque target value T ^* (the estimated amount of torque fluctuation [Delta] T), current and voltage to a target value generator 1 Output.

Thus, according to the first embodiment, the dq axis current detection values id, iq are set by setting the dq axis current target values id ^* , iq ^* according to the torque target value T ^* and the motor rotation speed N. ^* dq-axis current target value id the, iq dq-axis voltage target value vd ^* for matching the ^*, calculates the vq ^*, dq-axis voltage target value vd ^*, the three-phase alternating current of the three-phase AC coordinate system vq ^* voltage target value vu ^*, vv ^*, vw ^* three-phase AC voltage target value is converted into vu ^*, vv ^*, vw ^* three-phase AC voltage corresponding to the Vu, Vv, is applied to a three-phase synchronous motors and Vw In the motor controller to be driven, the motor torque is based on the torque target value T ^* , the motor rotation speed N, the dq axis voltage target values vd ^* , vq ^* , the dq axis current detection values id, iq, and the winding temperature detection value t. calculating a fluctuation amount [Delta] T, the torque target value by the torque fluctuation amount [Delta] T T ^* Since the correction is made, it is possible to estimate the torque fluctuation amount corresponding to both the magnet magnetic flux and the current magnetic flux due to the change of the magnet temperature, and even in the situation where the magnet temperature changes, regardless of the presence or absence of magnetic saturation Torque output in accordance with the torque target value T ^* can be obtained.

Further, according to the first embodiment, the dq-axis voltage target values vd ^* and vq ^* and the winding temperature detection value t when the motor outputs torque equal to the torque target value T ^* are used as the reference voltage vd_ref. , Vq_ref and reference temperature tref are stored in advance as table data of torque target value T ^* and reference voltages vd_ref, vq_ref and reference temperature tref with respect to motor rotation speed N, and dq axis voltage is referenced with reference to these table data The difference between the target values vd ^* and vq ^* and the reference voltages vd_ref and vq_ref and the difference between the winding temperature detection value t and the reference temperature tref are calculated, and these differences are used to cause the temperature change of the magnet magnetic flux of the motor. Since the torque fluctuation amount ΔT is calculated, the torque fluctuation amount corresponding to both the magnet magnetic flux and the current magnetic flux caused by the change in the magnet temperature can be estimated, and the magnet temperature changes. Torque output of the torque target value T ^* as with or without magnetic saturation can be obtained in a situation.

According to the first embodiment, the motor is a reference for the previously measured torque target value T ^* and motor rotational speed N as reference torque Tref the estimated torque T when outputs the torque equal to the torque target value T ^* Table data of torque Tref is stored, current estimated torque T is calculated, difference between current estimated torque T and reference torque Tref is calculated with reference to the table data, and the motor magnet is calculated using this difference. Since the torque fluctuation amount ΔT due to the temperature change of the magnetic flux is calculated, the torque fluctuation amount corresponding to both the magnet magnetic flux and the current magnetic flux due to the magnet temperature change can be estimated, and the magnet temperature changes. Even in such a situation, a torque output according to the torque target value T ^* can be obtained regardless of the presence or absence of magnetic saturation. Further, since it is only necessary to store only the table data of the reference torque Tref, the memory capacity and the table reference time can be reduced, and the cost reduction and the speeding up of the arithmetic processing can be realized.

According to the first embodiment, the motor is a reference for the estimated power P measured in advance torque target as reference power Pref value T ^* and motor rotation speed N at output of torque equal to the torque target value T ^* Table data of the power Pref is stored, the current estimated power P is calculated, the difference between the current estimated power P and the reference power Pref is calculated with reference to the table data, and the motor magnet is calculated using this difference. Since the torque fluctuation amount ΔT due to the temperature change of the magnetic flux is calculated, the torque fluctuation amount corresponding to both the magnet magnetic flux and the current magnetic flux due to the magnet temperature change can be estimated, and the magnet temperature changes. Even in such a situation, a torque output according to the torque target value T ^* can be obtained regardless of the presence or absence of magnetic saturation. Further, since it is only necessary to store only the table data of the reference power Pref, the memory capacity and the table reference time can be reduced, and cost reduction and calculation processing speed can be realized.

According to the first embodiment, table data obtained by measuring motor induced voltages vd ^* _dcpl and vq ^* _dcpl with respect to the torque target value T ^* and the motor rotation speed N is stored, and the torque target value is obtained from the table data. The induced voltage vd ^* _dcpl, vq ^* _dcpl of the motor according to T ^* and the motor rotation speed N is obtained, and the torque fluctuation due to the temperature change of the magnet magnetic flux of the motor is obtained using the induced voltage vd ^* _dcpl, vq ^* _dcpl. Since the amount is calculated, it is possible to estimate the amount of torque fluctuation corresponding to both the magnetic flux and current flux caused by the change in magnet temperature. Regardless, the torque output according to the torque target value T ^* can be obtained. Further, since only the table data of the induced voltages vd ^* _dcpl and vq ^* _dcpl needs to be stored, the memory capacity and the table reference time can be reduced, and the cost can be reduced and the calculation process can be speeded up.

<< Second Embodiment of the Invention >>
In the first embodiment described above, the method of estimating the torque fluctuation amount ΔT due to the temperature change of the magnet magnetic flux has been described. However, in this second embodiment, the current detection value change amount due to the temperature change of the current detectors 6a and 6b. The estimation method of will be described.

FIG. 6 is a diagram showing the configuration of the second embodiment. In FIG. 6, the same components as those in the control blocks (control circuits) and devices shown in FIGS. 1, 3, and 4 are denoted by the same reference numerals, and different points will be mainly described. In the first embodiment, the torque target value T ^* is corrected by the torque fluctuation amount ΔT, and the corrected torque target value T ^* ′ is input to the current / voltage target value generator 1. In the second embodiment, the torque target value T ^* is input to the current / voltage target value generator 1 without being corrected.

The detected current value change amount calculation unit 11C includes a reference voltage / winding temperature generator 12 and a detected current value change amount estimator 13C. As described above, the reference voltage / winding temperature generator 12 refers to the data table to obtain the reference voltage values vd_ref, vq_ref and the reference winding temperature tref according to the current torque target value T ^* , the motor rotation speed N, and so on. get. The detected current value change amount estimator 13C includes the reference voltage values vd_ref and vq_ref inputted from the reference voltage / winding temperature generator 12, the reference winding temperature tref, and the voltage target values vd ^* and vq inputted from the current vector controller 2. ^{* Based} on the detected currents id and iq input from the coordinate converter 10 and the winding temperature t input from the winding temperature detector 14, the detected current value changes Δid and Δiq are estimated. The method for estimating the detected current value variations Δid and Δiq will be described in detail later.

  The estimated current detection value changes Δid and Δiq are subjected to noise reduction processing by the low-pass filters 16a and 16b, respectively, and further subjected to PI calculation amplification processing by the PI amplifiers 15a and 15b. Then, the adder 17a, 17b corrects the detected current value (detected current) id, iq by subtracting the detected current value variation Δid, Δiq and corrects the corrected current detected value id ′, iq ′ with the current vector controller 2. Enter.

<< Method 1 for Estimating Current Detection Value Changes Δid and Δiq 1 >>
Next, a method for estimating the detected current value changes Δid and Δiq due to temperature changes of the current detector 14 will be described. The current detector 14 may change the slope of the detected value with respect to the actual current as shown in FIG. In FIG. 7, compared with the detection characteristic at time t = t1, the detection characteristic at time t = t2 when the temperature of the detector 14 has increased has a smaller slope of the detection value with respect to the actual current.

In such a case, although the same actual current flows before and after the temperature change at time t = t1, t2, the amplitude of the detected three-phase AC current value changes as shown in FIG. , A change as shown in FIG. 9 occurs in the current detection value on the dq axis. When such a change occurs, the current vector controller 2 changes the voltage target values vd ^* and vq ^* so that the detected current values id and iq match the current target values id ^* and iq ^* , respectively. Changes and the motor torque fluctuates.

In the equations (1) and (2), when the current detection values id and iq change, the changes Δvd and Δvq of the dq axis input voltages vd and vq with respect to the changes Δid and Δiq of the current detection values id and iq are wound. The following equation is obtained by considering the winding resistance change due to the temperature change of the wire.

として算出することができる。入力電圧ｖd、ｖqの変動分Δｖd、Δｖqおよび巻線抵抗Ｒの変動分ΔＲおよび現在の巻線抵抗Ｒ(t)は、（７）、（８）、（１１）式で算出する。また、インダクタンスＬd、Ｌqの情報が必要であるが、上述したようにインダクタンスは磁束の飽和状況によって代わるため、動作状況に応じた値をテーブルデータ化して持っておく必要がある。 When the equation (14) is solved for the detected current value variations Δid and Δiq,

Can be calculated as The variations Δvd and Δvq of the input voltages vd and vq, the variation ΔR of the winding resistance R, and the current winding resistance R (t) are calculated by the equations (7), (8), and (11). Further, although information on the inductances Ld and Lq is necessary, since the inductance is changed depending on the saturation state of the magnetic flux as described above, it is necessary to have values corresponding to the operation state as table data.

巻線抵抗Ｒ(t)＞０、ｄｑ軸インダクタンスＬd、Ｌq＞０であり、電気角速度ωは正転なら正、逆転なら負の値を示す。 << Method 2 for Estimating Current Detection Value Changes Δid and Δiq 2 >>
Next, another estimation method of the detected current change amounts Δid and Δiq due to the temperature change of the current detector 14 will be described. In this estimation method 2, equation (14) is modified as follows.

Winding resistance R (t)> 0, dq-axis inductance Ld, Lq> 0, and the electrical angular velocity ω is positive for normal rotation and negative for reverse rotation.

ここで、“象限”はモーターの回転方向すなわち正転か逆転か、および出力トルクの正負すなわち力行か制動かにより決まるモーターの動作状態を表し、第１象限は正転の力行状態を、第２象限は正転の制動状態を、第３象限は逆転の力行状態を、第４象限は逆転の制動状態をそれぞれ表す。モーター７の回転方は、位置変換器８の出力や速度演算器９の出力の符号により判別することができる。また、モーター７の出力トルクの正負は、座標変換器１０から出力されるｄｑ軸電流ｉd、ｉqの符号やトルク目標値Ｔ^＊の符号により判別することができる。表１において、第１象限と第３象限ではΔｉａと（１６）式左辺ｄ軸成分の符号に、第２象限と第４象限ではΔｉａと（１６）式左辺ｑ軸成分の符号に一定の関係がある。 Table 1 shows the relationship between the sign of the current detection value change amount ia in FIG. 9 and the sign of each value in equation (16).

Here, “quadrant” represents the motor operating state determined by the rotational direction of the motor, that is, forward rotation or reverse rotation, and whether the output torque is positive or negative, that is, power running or braking, and the first quadrant represents the forward running power running state, The quadrant represents the forward braking state, the third quadrant represents the reverse power running state, and the fourth quadrant represents the reverse braking state. The rotation method of the motor 7 can be determined by the sign of the output of the position converter 8 or the output of the speed calculator 9. The sign of the output torque of the motor 7 can be determined by the sign of the dq axis currents id and iq output from the coordinate converter 10 and the sign of the torque target value T ^* . In Table 1, there is a fixed relationship between Δia and the sign of the left-hand side d-axis component of Equation (16) in the first quadrant and the third quadrant, and Δia and the sign of the left-hand side q-axis component of Equation (16) in the second and fourth quadrants. There is.

Therefore, either the d-axis component or the q-axis component on the left side of the equation (16) is selected according to the current quadrant, and the detected current value change amount Δid is expressed by the equation (17) according to the selected value. , Δiq is determined, and the current detection value is corrected by PI amplification as shown in FIG. 6, the relationship between the actual current and the current feedback value input to the current vector controller 2 is the current detector 6a, 6b. As a result, the torque fluctuation due to the change of the current detection value due to the temperature change of the current detectors 6a and 6b can be suppressed.

  Here, the calculated current detection value variations Δid and Δiq do not necessarily match the actual values, but eventually the left side of the equation (16) is asymptotic to 0, and the output of the PI amplifier 15 is also the actual current detection value. Asymptotically approaches the change amounts Δid and Δiq. Furthermore, since this method does not require information on the inductance values Ld and Lq, it is not necessary to prepare table data relating to the inductance value. As described above, even if the current detection values id and iq change due to temperature changes of the current detectors 6a and 6b, the change amounts Δid and Δiq can be estimated and corrected appropriately, and torque fluctuation can be suppressed.

（１７）式も同様にして、

<< Method 3 for Estimating Current Detection Value Changes Δid, Δiq 3 >>
Next, another estimation method of the current detection value change amounts Δid and Δiq due to the temperature change of the current detector 14 will be described. Equation (15) can be replaced from Equation (12) as follows.

Similarly, formula (17)

If the induced voltages vd ^* _dcpl and vq ^* _dcpl for the torque target value T ^* calculated for the vector current control are used according to the equations (12), (18) and (19) as shown in FIG. Without preparing voltage / winding temperature reference value table data, torque fluctuations due to temperature changes of the current detectors 6a and 6b can be suppressed.

10, components similar to those in the control block (control circuit) and the devices shown in FIGS. 1, 3, 4, and 6 are denoted by the same reference numerals and different points will be mainly described. The detected current value change amount calculation unit 11D includes only the detected current value change amount estimator 13D. The detected current value change amount estimator 13D includes induced voltages vd ^* _dcpl and vq ^* _dcpl incident from the current / voltage target value generator 1, voltage target values vd ^* and vq ^* input from the current vector controller 2, and coordinate conversion. On the basis of the detected currents id and iq input from the generator 10 and the winding temperature t input from the winding temperature detector 14, the detected current value variations Δid and Δiq are expressed by the equations (12), (18), and (19). presume.

  FIG. 11 is a flowchart showing a current detection value correction process according to the second embodiment. The operation of the second embodiment will be described with reference to this flowchart. When the motor control device of the second embodiment is started, the current detection value correction process shown in FIG. 11 is repeatedly executed, and the current detectors 6a and 6b are based on the corrected current detection values id 'and iq'. Suppresses fluctuations in motor torque caused by temperature changes.

In step 11, reference parameters for correcting the current detection values id and iq are acquired according to the above-described estimation methods 1 to 3 of the current detection value change amounts Δid and Δiq. In the case of the estimation methods 1 and 2, the reference voltage / winding temperature generator 12 shown in FIG. 6 refers to the data table and refers to the current torque target value T ^* and the reference voltage value vd_ref according to the motor rotation speed N. Obtain vq_ref and reference winding temperature tref. In the case of the estimation method 3, the current / voltage generator 1a shown in FIG. 10 refers to the data table and obtains the induced voltages vd ^* _dcpl and vq ^* _dcpl corresponding to the current torque target value T ^* and the motor rotational speed N. To do.

In subsequent step 12, current detection values id and iq are obtained from the coordinate converter 10, and voltage target values vd ^* and vq ^* are obtained from the current vector controller 2, respectively. Further, in step 13, the winding temperature t is acquired from the winding temperature detector 14. In step 14, the detected current value changes Δid and Δiq are estimated according to the estimation methods 1 to 3. In the case of the estimation methods 1 and 2, the reference voltage values vd_ref and vq_ref, the reference winding temperature tref, the voltage target values vd ^* and vq ^* , the detection currents id and iq, and the detected current value change amount estimator 13C shown in FIG. Based on the winding temperature t, current detection value change amounts Δid and Δiq are calculated. In the case of the estimation method 3, the induced voltage vd ^* _dcpl, vq ^* _dcpl, voltage target value vd ^* , vq ^* , detected current id, iq, and winding temperature t are detected by the current detection value change amount estimator 11D shown in FIG. Based on, current detection value change amounts Δid and Δiq are calculated.

  In step 15 after calculating the detected current value changes Δid and Δiq, noise reduction processing is performed on the calculated detected current value changes Δid and Δiq by the low-pass filters 16a and 16b, respectively, and PI (proportional / integral) is performed. ) PI operational amplification processing is performed by the amplifiers 15a and 15b. Finally, at step 16, the adders 17a and 17b subtract the outputs of the PI amplifiers 15a and 16 (current detection value variations Δid and Δiq) from the current detection values id and iq to calculate the current detection values id 'and iq'. And output to the current vector controller 2.

As described above, according to the second embodiment, the dq-axis current detection values id, iq are set by setting the dq-axis current target values id ^* , iq ^* according to the torque target value T ^* and the motor rotation speed N. ^* dq-axis current target value id the, iq dq-axis voltage target value vd ^* for matching the ^*, calculates the vq ^*, dq-axis voltage target value vd ^*, the three-phase alternating current of the three-phase AC coordinate system vq ^* voltage target value vu ^*, vv ^*, vw ^* three-phase AC voltage target value is converted into vu ^*, vv ^*, vw ^* three-phase AC voltage corresponding to the Vu, Vv, is applied to a three-phase synchronous motors and Vw In a motor control device to be driven, a current detector based on a torque target value T ^* , a motor rotation speed N, a dq axis voltage target value vd ^* , vq ^* , a dq axis current detection value id, iq, and a winding temperature detection value t Current detection value change amount Δid, Δiq caused by temperature change of Since the dq-axis current detection values id and iq are corrected by the amount of change Δid and Δiq, the accurate current can be obtained even in a situation where the slope characteristic of the current detection value with respect to the actual current changes due to the temperature change of the current detector. Detection values id and iq are obtained, and torque outputs corresponding to the torque target value T ^* are obtained.

Further, according to the second embodiment, the dq-axis voltage target values vd ^* and vq ^* and the winding temperature detection value t when the motor outputs a torque equal to the torque target value T ^* are used as the reference voltage vd_ref. , Vq_ref and reference temperature tref are stored in advance as table data of torque target value T ^* and reference voltages vd_ref, vq_ref and reference temperature tref with respect to motor rotation speed N, and dq axis voltage is referenced with reference to these table data The difference between the target values vd ^* , vq ^* and the reference voltages vd_ref, vq_ref and the difference between the winding temperature detection value t and the reference temperature tref are calculated, and the current resulting from the temperature change of the current detector is calculated using these differences. Since the detection value change amounts Δid and Δiq are calculated, the current detection value id is accurate even in a situation where the slope characteristic of the current detection value with respect to the actual current changes due to the temperature change of the current detector. , Iq, and a torque output corresponding to the torque target value T ^* is obtained.

According to the second embodiment, the operation quadrant of the motor is detected, and the current detection value change amounts Δid and Δiq caused by the temperature change of the current detector are calculated according to the operation quadrant. Even in a situation where the slope characteristic of the current detection value with respect to the actual current changes due to the temperature change of the device, more accurate current detection values id and iq can be obtained, and torque output according to the torque target value T ^* can be obtained.

According to the second embodiment, the table data obtained by measuring the motor target voltages vd ^* _dcpl and vq ^* _dcpl with respect to the torque target value T ^* and the motor rotation speed N is stored. The induced voltages vd ^* _dcpl and vq ^* _dcpl of the motor according to T ^* and the motor rotation speed N are obtained, and the current detection value change due to the temperature change of the current detector using the induced voltages vd ^* _dcpl and vq ^* _dcpl Since the amounts Δid and Δiq are calculated, accurate current detection values id and iq can be obtained even in a situation where the slope characteristic of the current detection value with respect to the actual current changes due to the temperature change of the current detector. Torque output of value T ^* is obtained. Further, since only the table data of the induced voltages vd ^* _dcpl and vq ^* _dcpl needs to be stored, the memory capacity and the table reference time can be reduced, and the cost can be reduced and the calculation process can be speeded up.

<< Third Embodiment of the Invention >>
FIG. 12 is a diagram showing the relationship of the output torque with respect to the rotational speed N of the motor. In FIG. 12, heat generation due to copper loss of the copper wire is large in a low rotation speed and high torque region in which a large current flows, so that the current detectors 6a and 6b attached in the vicinity of the copper wire easily move the heat of the copper wire. Large temperature change. However, since the eddy current loss of the magnet generated according to the harmonic component of the magnetic flux is small at a low rotational speed, there is almost no change in the magnet temperature. In addition, since a large current cannot flow as in a low rotational speed region in the high rotational speed region, the temperature change of the current detectors 6a and 6b is small, but the harmonic component of the magnetic flux becomes a high frequency. Increases, and the change in magnet temperature increases.

  By the way, in the first embodiment, since the change of the detected currents (current detection values) id and iq due to the temperature change of the current detectors 6a and 6b is not taken into consideration, it is good in the high rotation speed region where the change of the magnet temperature is large. Torque fluctuation suppressing effect can be obtained, but a sufficient effect may not be obtained in a low rotation speed and high torque region. On the other hand, in the second embodiment, since the change in magnetic flux due to the change in magnet temperature is not taken into consideration, a good torque fluctuation suppressing effect can be obtained in the low rotation speed region, but a sufficient effect can be obtained in the high rotation speed region. There may not be.

  Therefore, in the third embodiment, the torque target value correction control of the first embodiment and the current detection value correction control of the second embodiment are switched in accordance with the operation range of the motor rotation speed N. Apply. As for this switching method, the rotational speed N or the torque T may be weighted and gradually switched, or when there is an operation region that clearly does not need to be applied between the application regions, it may be switched nonlinearly.

  FIG. 13 is a control block diagram showing a switching method, and FIG. 14 is a timing chart showing a torque target correction value (torque fluctuation amount ΔT) and a current correction value (current detection value change amounts Δid, Δiq) at the time of switching. In FIG. 13, a control switching device 21 is provided to switch between the torque target value correction control of the first embodiment and the current detection value correction control of the second embodiment.

  When switching at the preset threshold value N0 of the rotational speed N, as shown in FIG. 14A, the weighting coefficient for the torque target correction value and the current correction value is switched from 1 → 0, 0 → 1, The torque target value correction control of the first embodiment and the current detection value correction control of the second embodiment are switched. Specifically, when the motor rotation speed N is equal to or greater than the threshold value N0, the weighting coefficient for the torque target correction value is set to 1 and the weighting coefficient for the current correction value is set to 0, so that the motor rotation speed N is the threshold. If the value is less than N0, 0 is set as the weighting coefficient for the torque target correction value, and 1 is set as the weighting coefficient for the current correction value.

  Further, as shown in FIG. 14B, when the threshold value N1 and the threshold value N2 (> N1) are set and the rotational speed N is between the threshold values N1 and N2, neither control is performed. You may do it. Further, as shown in FIG. 14 (c), a threshold value N1 and a threshold value N2 (> N1) are determined, and when the rotational speed N is between the threshold values N1 and N2, the rotational speed N The torque target value correction weighting coefficient and the current correction value weighting coefficient may be gradually changed.

  FIG. 15 is a flowchart showing the operation of the third embodiment. Steps that perform the same operations as those of the first embodiment shown in FIG. 5 and the second embodiment shown in FIG. To do. In step 21, the rotational speed N is acquired to detect the operation region. In this embodiment, for example, as shown in FIG. 12, in the rotation speed region where the rotation speed is N1 or less and the temperature change of the current detectors 6a and 6b is large and the rotation speed is high and the torque is high, The detected current value correction control in steps 1 to 6 shown in FIG. In addition, in the high rotational speed region where the harmonic component of the magnetic flux becomes high frequency at a rotational speed N2 (> N1) or higher, the eddy current loss of the magnet increases, and the change in the magnet temperature increases, the first implementation is performed. The torque target value correction control in steps 11 to 16 shown in FIG.

  In an intermediate speed region where the motor rotation speed N is larger than the threshold value N1 and smaller than the threshold value N2, in step 22, either current detection value correction control or torque target value correction control is performed as shown in FIG. Or a weighting coefficient by which the torque fluctuation amount ΔT is multiplied according to the motor rotation speed N in the intermediate speed region and a weighting coefficient by which the current detection value change amounts Δid and Δiq are multiplied, as shown in FIG. The current detection value correction control and the torque target value correction control are gradually switched.

Thus, according to the third embodiment, when the motor rotation speed N is equal to or greater than the predetermined threshold value N0, the weighting coefficient for the torque fluctuation amount ΔT is set to 1 and the detected current value change amount Δid. , Δiq is set to 0, and when the motor rotation speed N is less than a predetermined threshold value N0, the weighting coefficient for the torque fluctuation amount ΔT is set to 0, and the current detection value change amounts Δid, Δiq are set. The weighting coefficient is set to 1, the torque target value T ^* is corrected by the weighted torque fluctuation amount (ΔT), and the dq-axis current detection values id, iq are determined by the weighted current detection value changes (Δid, Δiq). Therefore, the effect of suppressing the motor torque fluctuation caused by the temperature change of the motor magnet and the temperature change of the current detector according to the motor rotation speed region is effective. Manner and can be reasonably achieved.

Further, according to the third embodiment, the threshold values N1 and N2 (> N1) of the motor rotation speed N are set, and when the motor rotation speed N is equal to or greater than the threshold value N2, the torque fluctuation amount ΔT is weighted. The coefficient is set to 1, and when the motor rotation speed N is less than the threshold value N2, the weighting coefficient for the torque fluctuation amount ΔT is set to 0, and when the motor rotation speed N is less than the threshold value N1, the current detection value is set. 1 is set as the weighting coefficient for the change amounts Δid and Δiq, and when the motor rotation speed N is larger than the threshold value N1, the weighting coefficient for the current detection value change amounts Δid and Δiq is set to 0, and the torque fluctuation after weighting is corrected torque target value by the amount (ΔT) T ^*, the current detection value change amount after weighting (.DELTA.id,? iq) by dq-axis current detection value id, it corrects the iq Since, it is possible to more effectively and rationally realized due to the motor torque fluctuation suppressing effect on the temperature change of the temperature change of the motor magnet and the current detector in accordance with the motor rotational speed region.

  Furthermore, according to the third embodiment, when the motor rotation speed N is larger than the threshold value N1 and smaller than the threshold value N2, the weighting coefficient for the torque fluctuation amount ΔT is increased according to the increase in the motor rotation speed N. While gradually increasing, the weighting coefficient for the current detection value change amounts Δid and Δiq is gradually reduced, which is caused by the temperature change of the motor magnet and the temperature change of the current detector according to the motor rotation speed region. The motor torque fluctuation suppression effect can be realized more effectively and rationally. In addition, the torque target value correction control due to the temperature change of the motor magnet and the current detection value change amount correction control due to the temperature change of the temperature detector can be started or ended smoothly, or both controls can be smoothly performed. It is possible to switch, and it is possible to avoid motor torque fluctuations and rotation speed fluctuations at the start and end of both controls and at the time of switching.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the position converter 8 and the speed calculator 9 are rotational speed detecting means, the winding temperature detector 14 is temperature detecting means, the current detectors 6a and 6b are current detecting means, and the coordinate converter 10 is a first coordinate. The coordinate converter 3 is the second coordinate converter, the current / voltage target value generator 1 is the target value generator, the current vector controller 2 is the current controller, the PWM converter 4 and the inverter 5 are The torque fluctuation amount calculation units 11, 11A and 11B are the torque fluctuation amount calculation means, the adder 17 is the torque target value correction means, and the current detection value change amount calculation units 11C and 11D are the current detection value change amount calculation. The adders 17a and 17b constitute current detection value correction means. The above description is merely an example, and when interpreting the invention, the correspondence between the items described in the above embodiment and the items described in the claims is not limited or restricted.

The figure which shows the structure of 1st Embodiment. Diagram showing an example of table data The figure which shows the torque fluctuation amount calculating part used with the estimation method 2 of a torque fluctuation amount. The figure which shows the structure of 1st Embodiment using the estimation method 3 of the amount of torque fluctuations. The flowchart which shows operation | movement of 1st Embodiment. The figure which shows the structure of 2nd Embodiment. Diagram showing temperature characteristics of current detector Diagram showing changes in three-phase alternating current due to temperature changes in the current detector The figure which shows the change of the electric current detection value on the dq axis by the temperature change of an electric current detector. The figure which shows the structure of the estimation method 3 of electric current detection value variation | change_quantity. Flowchart showing the operation of the third embodiment The figure which shows the relation of the output torque to the rotation speed of the motor Block diagram showing control switching method according to motor rotation speed range Timing chart showing how control is switched according to the motor speed range Flowchart showing the operation of the third embodiment

Explanation of symbols

1, 1a Current / voltage target value generator 2 Current vector controller 3, 10 Coordinate converter 4 PWM converter 5 Inverter 5a Battery 6a, 6b Current detector 7 Motor 8 Position detector 9 Speed calculator 11, 11A, 11B Torque fluctuation amount calculation units 11C, 11D Current detection value change amount calculation unit 12 Reference voltage / winding temperature generator 12A Reference power or reference torque generators 13, 13A, 13B Torque fluctuation amount estimators 13C, 13D Current detection value change amount Estimator 14 Winding temperature detector 15, 15 a, 15 b PI amplifier 16, 16 a, 16 b Low pass filter 17, 17 a, 17 b Adder 21 Control switching device

Claims (15)

A rotational speed detecting means for detecting the rotational speed of the three-phase synchronous motor;
Temperature detecting means for detecting the winding temperature of the motor;
Current detection means for detecting a three-phase alternating current flowing in the motor;
First coordinate conversion means for converting the three-phase alternating current detection value into a dq axis current detection value in a dq axis coordinate system;
Target value generating means for setting a dq-axis current target value according to a torque target value and the motor rotation speed;
Current control means for calculating a dq-axis voltage target value for making the dq-axis current detection value coincide with the dq-axis current target value;
Second coordinate conversion means for converting the dq-axis voltage target value into a three-phase AC voltage target value in a three-phase AC coordinate system;
In a motor control device comprising driving means for applying and driving a three-phase AC voltage corresponding to the three-phase AC voltage target value to the motor,
Torque fluctuation amount calculating means for calculating the torque fluctuation amount of the motor based on the torque target value, the motor rotation speed, the dq axis voltage target value, the dq axis current detection value, and the winding temperature detection value;
Torque target value correcting means for correcting the torque target value by the torque fluctuation amount,
The torque fluctuation amount calculating means measures the torque measured in advance using the dq axis voltage target value and the winding temperature detection value as a reference voltage and a reference temperature when the motor outputs a torque equal to the torque target value. Table data of the reference voltage and the reference temperature with respect to the target value and the motor rotation speed are stored, and the difference between the dq-axis voltage target value and the reference voltage and the winding temperature are referred to with reference to these table data A motor control device , wherein a difference between a detected value and the reference temperature is calculated, and the torque fluctuation amount caused by a temperature change of the magnet magnetic flux of the motor is calculated using these differences . A rotational speed detecting means for detecting the rotational speed of the three-phase synchronous motor;
Temperature detecting means for detecting the winding temperature of the motor;
Current detection means for detecting a three-phase alternating current flowing in the motor;
First coordinate conversion means for converting the three-phase alternating current detection value into a dq axis current detection value in a dq axis coordinate system;
Target value generating means for setting a dq-axis current target value according to a torque target value and the motor rotation speed;
Current control means for calculating a dq-axis voltage target value for making the dq-axis current detection value coincide with the dq-axis current target value;
Second coordinate conversion means for converting the dq-axis voltage target value into a three-phase AC voltage target value in a three-phase AC coordinate system;
In a motor control device comprising driving means for applying and driving a three-phase AC voltage corresponding to the three-phase AC voltage target value to the motor,
Torque fluctuation amount calculating means for calculating the torque fluctuation amount of the motor based on the torque target value, the motor rotation speed, the dq axis voltage target value, the dq axis current detection value, and the winding temperature detection value;
Torque target value correcting means for correcting the torque target value by the torque fluctuation amount,
The torque fluctuation amount calculating means is a table data of the reference torque with respect to the torque target value and the motor rotation speed measured in advance using the estimated torque when the motor outputs a torque equal to the torque target value as a reference torque. And calculating a current estimated torque based on the dq-axis voltage target value, the dq-axis current detection value, and the winding temperature detection value, and referring to the table data, A motor control device that calculates a difference from the reference torque and calculates the torque fluctuation amount corresponding to both a magnet magnetic flux and a current magnetic flux caused by a change in the magnet temperature of the motor using the difference. . A rotational speed detecting means for detecting the rotational speed of the three-phase synchronous motor;
Temperature detecting means for detecting the winding temperature of the motor;
Current detection means for detecting a three-phase alternating current flowing in the motor;
First coordinate conversion means for converting the three-phase alternating current detection value into a dq axis current detection value in a dq axis coordinate system;
Target value generating means for setting a dq-axis current target value according to a torque target value and the motor rotation speed;
Current control means for calculating a dq-axis voltage target value for making the dq-axis current detection value coincide with the dq-axis current target value;
Second coordinate conversion means for converting the dq-axis voltage target value into a three-phase AC voltage target value in a three-phase AC coordinate system;
In a motor control device comprising driving means for applying and driving a three-phase AC voltage corresponding to the three-phase AC voltage target value to the motor,
Torque fluctuation amount calculating means for calculating the torque fluctuation amount of the motor based on the torque target value, the motor rotation speed, the dq axis voltage target value, the dq axis current detection value, and the winding temperature detection value;
Torque target value correcting means for correcting the torque target value by the torque fluctuation amount,
The torque fluctuation amount calculating means is a table data of the reference power with respect to the torque target value and the motor rotation speed measured in advance using the estimated power when the motor outputs torque equal to the torque target value as reference power. And calculating the current estimated power based on the dq-axis voltage target value, the dq-axis current detection value, and the winding temperature detection value, and referring to the table data, A motor control device that calculates a difference from the reference power and calculates the torque fluctuation amount corresponding to both a magnet magnetic flux and a current magnetic flux caused by a change in magnet temperature of the motor using the difference. . A rotational speed detecting means for detecting the rotational speed of the three-phase synchronous motor;
Temperature detecting means for detecting the winding temperature of the motor;
Current detection means for detecting a three-phase alternating current flowing in the motor;
First coordinate conversion means for converting the three-phase alternating current detection value into a dq axis current detection value in a dq axis coordinate system;
Target value generating means for setting a dq-axis current target value according to a torque target value and the motor rotation speed;
Current control means for calculating a dq-axis voltage target value for making the dq-axis current detection value coincide with the dq-axis current target value;
Second coordinate conversion means for converting the dq-axis voltage target value into a three-phase AC voltage target value in a three-phase AC coordinate system;
In a motor control device comprising driving means for applying and driving a three-phase AC voltage corresponding to the three-phase AC voltage target value to the motor,
Torque fluctuation amount calculating means for calculating the torque fluctuation amount of the motor based on the torque target value, the motor rotation speed, the dq axis voltage target value, the dq axis current detection value, and the winding temperature detection value;
Torque target value correcting means for correcting the torque target value by the torque fluctuation amount,
The torque fluctuation amount calculating means stores table data obtained by measuring an induced voltage of the motor with respect to the torque target value and the motor rotation speed, and according to the torque target value and the motor rotation speed from the table data. A motor control device characterized in that an induced voltage of the motor is obtained, and the torque fluctuation amount due to a temperature change of a magnet magnetic flux of the motor is calculated using the induced voltage. In the motor control device according to any one of claims 1 to 4 ,
Based on the torque target value, the motor rotation speed, the dq-axis voltage target value, the dq-axis current detection value, and the winding temperature detection value, a current detection value change amount caused by a temperature change of the current detection means is calculated. Current detection value change amount calculating means to perform,
A motor control device comprising: current detection value correction means for correcting the dq-axis current detection value based on the current detection value change amount. The motor control device according to claim 5 ,
The current detection value change amount calculation means pre-measures the dq axis voltage target value and the winding temperature detection value when the motor outputs a torque equal to the torque target value as a reference voltage and a reference temperature. Table data of the reference voltage and the reference temperature with respect to the torque target value, the motor rotation speed is stored, and the difference between the dq-axis voltage target value and the reference voltage and the winding are referred to with reference to these table data. A motor control device that calculates a difference between a detected line temperature value and the reference temperature, and calculates a change amount of a detected current value caused by a temperature change of the current detection means using the difference. The motor control device according to claim 6 ,
The current detection value change amount calculation means detects an operation quadrant of the motor, and calculates a current detection value change amount caused by a temperature change of the current detection means according to the operation quadrant. apparatus. The motor control device according to claim 5 ,
The current detection value change amount calculating means stores table data obtained by measuring the induced voltage of the motor with respect to the torque target value and the motor rotation speed. From the table data, the torque target value and the motor rotation speed are stored. A motor control device characterized by obtaining an induced voltage of the motor according to the response, and calculating a current detection value change amount caused by a temperature change of the current detection means using the induced voltage. The motor control device according to any one of claims 5 to 8 ,
When the motor rotation speed is equal to or greater than a predetermined threshold N0, the weighting coefficient for the torque fluctuation amount is set to 1, and the weighting coefficient for the current detection value change amount is set to 0, so that the motor rotation speed is A weighting means for setting the weighting coefficient for the torque fluctuation amount to 0 and setting the weighting coefficient for the current detection value change amount to 1 when the torque threshold is less than the predetermined threshold N0;
The torque target value correcting means corrects the torque target value by the torque fluctuation amount after weighting by the weighting means,
The current detection value correction means corrects the dq-axis current detection value based on the amount of change in the current detection value after weighting by the weighting means. The motor control device according to any one of claims 5 to 8 ,
The motor rotation speed thresholds N1 and N2 (> N1) are set. When the motor rotation speed is equal to or greater than the threshold N2, the weighting coefficient for the torque fluctuation amount is set to 1 and the motor rotation speed is set. Is less than the threshold value N2, the weighting coefficient for the torque fluctuation amount is set to 0. When the motor rotation speed is equal to or less than the threshold value N1, the weighting coefficient for the current detection value change amount is set to 1. And a weighting means for setting a weighting coefficient for the current detection value change amount to 0 when the motor rotation speed is greater than a threshold value N1,
The torque target value correcting means corrects the torque target value by the torque fluctuation amount after weighting by the weighting means,
The current detection value correction means corrects the dq-axis current detection value based on the amount of change in the current detection value after weighting by the weighting means. The motor control device according to claim 10 ,
When the motor rotation speed is greater than the threshold value N1 and less than the threshold value N2, the weighting means gradually increases a weighting coefficient for the torque fluctuation amount according to the increase in the motor rotation speed, and A motor control device characterized by gradually reducing a weighting coefficient for a current detection value change amount. A rotational speed detecting means for detecting the rotational speed of the three-phase synchronous motor;
Temperature detecting means for detecting the winding temperature of the motor;
Current detection means for detecting a three-phase alternating current flowing in the motor;
First coordinate conversion means for converting the three-phase alternating current detection value into a dq axis current detection value in a dq axis coordinate system;
Target value generating means for setting a dq-axis current target value according to a torque target value and the motor rotation speed;
Current control means for calculating a dq-axis voltage target value for making the dq-axis current detection value coincide with the dq-axis current target value;
Second coordinate conversion means for converting the dq-axis voltage target value into a three-phase AC voltage target value in a three-phase AC coordinate system;
In a motor control device comprising driving means for applying and driving a three-phase AC voltage corresponding to the three-phase AC voltage target value to the motor,
Based on the torque target value, the motor rotation speed, the dq-axis voltage target value, the dq-axis current detection value, and the winding temperature detection value, a current detection value change amount caused by a temperature change of the current detection means is calculated. Current detection value change amount calculating means to perform,
A motor control device comprising: current detection value correction means for correcting the dq-axis current detection value based on the current detection value change amount. The motor control device according to claim 12 ,
The current detection value change amount calculation means pre-measures the dq axis voltage target value and the winding temperature detection value when the motor outputs a torque equal to the torque target value as a reference voltage and a reference temperature. Table data of the reference voltage and the reference temperature with respect to the torque target value, the motor rotation speed is stored, and the difference between the dq-axis voltage target value and the reference voltage and the winding are referred to with reference to these table data. A motor control device that calculates a difference between a detected line temperature value and the reference temperature, and calculates a change amount of a detected current value caused by a temperature change of the current detection means using the difference. The motor control device according to claim 13 ,
The current detection value change amount calculation means detects an operation quadrant of the motor, and calculates a current detection value change amount caused by a temperature change of the current detection means according to the operation quadrant. apparatus. The motor control device according to claim 12 ,
The current detection value change amount calculating means stores table data obtained by measuring the induced voltage of the motor with respect to the torque target value and the motor rotation speed. From the table data, the torque target value and the motor rotation speed are stored. A motor control device characterized by obtaining an induced voltage of the motor according to the response, and calculating a current detection value change amount caused by a temperature change of the current detection means using the induced voltage.

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