JP2007274783A - Electromotive drive control unit, and electromotive drive control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the capacity of a recorder for forming a torque correction map and drive an electric machine with high precision. <P>SOLUTION: This electromotive drive control unit includes: an electric machine target torque calculating unit for calculating electric machine target torque; a variable acquiring unit for acquiring an electric machine rotational speed and an electric machine target torque; a target power calculating unit for calculating target power for driving electric machine; and an electric machine target torque correcting unit for referring to a torque correction map recording torque correction values of electric machine target torque for correcting electric machine target torque correcting unit for correcting electric machine target torque, based on a torque correction value corresponding to an electric machine rotational speed and an electric machine target torque when the electric machine rotational speed is lower than a predetermined region boundary speed, and based on a torque correction value corresponding to the electric machine rotational speed and target power when the electric machine rotational speed is higher than the region boundary speed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric drive control device and an electric drive control method.

  2. Description of the Related Art Conventionally, a drive motor or a generator provided as an electric machine includes a rotor that is rotatably provided and has a magnetic pole pair made up of N-pole and S-pole permanent magnets, and is arranged radially outward from the rotor. And a stator or the like having U-phase, V-phase, and W-phase stator coils.

  An electric drive device is disposed to drive the drive motor or the generator and generate a drive motor torque that is the torque of the drive motor or a generator torque that is the torque of the generator. A drive motor control device for driving the drive motor and a generator control device for driving the generator are arranged as an electric machine control device, and the U phase and V phase generated in the electric machine control device are arranged. And the W-phase pulse width modulation signal is sent to the inverter, and phase currents generated in the inverter, that is, U-phase, V-phase, and W-phase currents are supplied to the respective stator coils, thereby driving the drive motor torque. Or generator torque is generated.

  In the drive motor control device, feedback control is performed by vector control calculation on a dq axis model in which the d axis is taken in the direction of the magnetic pole pair in the rotor and the q axis is taken in a direction perpendicular to the d axis. For this purpose, the drive motor control device detects the current supplied to each stator coil, the magnetic pole position of the rotor, the DC voltage at the inlet of the inverter, etc., and the detected current, that is, the detected current is based on the magnetic pole position. The d-axis current and the q-axis current are converted into the d-axis current and the q-axis current, and the d-axis current command value and the q-axis current command value representing the target values of the d-axis current and the q-axis current are calculated with reference to the current command value map, The d-axis voltage command value and the q-axis voltage command value are calculated based on the deviation between the d-axis current and the d-axis current command value, the deviation between the q-axis current and the q-axis current command value, and the parameters of the drive motor. ing.

  In the current command value map, a d-axis current command value and a q-axis current command value are recorded in association with the drive motor target torque representing the target value of the drive motor torque, the DC voltage, and the angular velocity. The parameters include a back electromotive force constant MIf, a winding resistance Ra of each stator coil, inductances Ld, Lq, and the like (see, for example, Patent Document 1).

  By the way, when the d-axis current command value and the q-axis current command value corresponding to the drive motor target torque are read from the current command value map and the drive motor is driven, the drive motor torque according to the drive motor target torque can be generated. There are things that cannot be done. Therefore, it is conceivable to correct the drive motor target torque with a torque correction map and drive the drive motor based on the d-axis current command value and the q-axis current command value corresponding to the corrected drive motor target torque.

FIG. 2 is a diagram showing a conventional torque correction map. In the figure, the horizontal axis represents the drive motor rotational speed NM, and the vertical axis represents the drive motor target torque TM ^* .

In the figure, O is the origin, and Ni (i = 1, 2,..., P) is a predetermined interval by equally dividing the upper limit value of the drive motor rotational speed NM and zero (0). The line Tj (j = 1, 2,..., Q) that is set for each drive motor rotation speed NM is evenly divided between the theoretical upper limit value of the drive motor target torque TM ^* and zero. By dividing, the line is set for each predetermined interval and represents the drive motor target torque TM ^{*. At} each point where the lines Ni and Tj intersect, that is, at each intersection, the drive motor rotational speed NM and the drive motor target The correction value δTM ^* corresponding to the torque TM ^* is
-Α1 ≦ δTM ^* ≦ + α2 (α1, α2> 0)
Is set and recorded as follows. Α1 and α2 are preset values, and the line Tj constitutes an equal torque line. Further, the rotational speed of the electric machine is configured by the rotational speed NM of the drive motor.

Therefore, when the drive motor rotational speed NM and the drive motor target torque TM ^* are specified, the correction value δTM ^* is read from the torque correction map, and the correction value δTM ^* is subtracted from the drive motor target torque TM ^*. It is corrected. Then, the drive motor is driven based on the corrected drive motor target torque TM ^* . The correction value of the driving motor target torque TM ^* between the drive motor rotation speed NM, and the intersections between the intersections? Tm ^* is calculated by interpolating the correction value? Tm ^* at each intersection.

  By the way, when the drive motor is driven, the output does not reach the upper limit in the low speed region where the drive motor rotational speed NM is lower than the predetermined value, that is, the region boundary speed Ns. The maximum value of the drive motor torque TM is constant because the output is the upper limit value in a high speed region that is higher than the region boundary speed Ns and equal to or lower than the upper limit value. It cannot be set to a value and decreases as the drive motor rotational speed NM increases.

Therefore, when actually setting the drive motor target torque TM ^* , the maximum representing the maximum value of the drive motor target rotation speed NM ^* for each drive motor rotation speed NM in the low speed region in accordance with the characteristics of the drive motor. The drive motor target torque TM ^* max is made constant, and in the high speed region, the maximum drive motor target torque TM ^* max needs to be lowered as the drive motor rotational speed NM increases.

Therefore, in forming the torque correction map, it is preferable that the maximum drive motor target torque TM ^* max is set to be lower in the high speed region so that the maximum drive motor target torque TM ^* max is constant in the low speed region. In this case, in the high speed region, if the drive motor rotational speed NM is different, the distance between the intersections on the line Ni is different, so that it becomes extremely difficult to interpolate.

Therefore, as shown in FIG. 2, on the torque correction map, the maximum drive motor target torque TM ^* max is constant in both the low speed region and the high speed region, and each line Tj is parallel to the horizontal axis. Is set to be
Japanese Patent Laid-Open No. 5-130710

However, in the conventional electric drive device, the capacity of the recording device on which the torque correction map is formed becomes unnecessarily large. That is, when driving the drive motor, the maximum drive motor target torque TM ^* max that is actually set is lowered as the drive motor rotation speed NM increases in the high speed region, whereas on the torque correction map, Since the maximum drive motor target torque TM ^* max is fixed, a torque correction map is unnecessarily formed in the region where the drive motor target torque TM ^* is large in the high speed region, that is, in the high speed / high torque region. Therefore, the memory area is wasted. Therefore, the capacity of the recording apparatus is increased accordingly.

  Even in the high-speed region, each line Tj is set in parallel to the horizontal axis, so that the resolution is lowered. Therefore, the drive motor cannot be driven with high accuracy.

  The present invention solves the problems of the conventional electric drive device, reduces the capacity of the recording device for forming the torque correction map, and can drive the electric machine with high accuracy. An object is to provide an apparatus and an electric drive control method.

  Therefore, in the electric drive control device of the present invention, the electric machine, the electric machine target torque calculation processing means for calculating the electric machine target torque that represents the target value of the torque of the electric machine, and the rotational speed of the electric machine. The variable power acquisition processing means for acquiring the electric machine rotation speed and the electric machine target torque, and the target power calculation for calculating the target power for driving the electric machine based on the electric machine rotation speed and the electric machine target torque Refer to the processing means and the torque correction map in which the torque correction value of the electric machine target torque is recorded, and when the electric machine rotation speed is lower than a preset region boundary speed, the electric machine rotation speed and the electric machine target torque When the electric machine rotation speed is equal to or greater than the region boundary speed based on the torque correction value corresponding to Having an electric machine target torque correction processing means for correcting the electric machine target torque based on the torque correction value corresponding to the power.

  In another electric drive control device of the present invention, the torque correction map is a coordinate system of an electric machine rotation speed and an electric machine target torque in a low speed region where the electric machine rotation speed is lower than a region boundary speed. In the high speed region where the rotational speed is equal to or higher than the region boundary speed, the coordinate system is formed of the electric machine rotational speed and the target power.

  In still another electric drive control device of the present invention, the torque correction map is formed for each DC voltage.

  In still another electric drive control device of the present invention, the region boundary speed is the highest electric machine rotation speed among the electric machine rotation speeds taking the maximum value of the electric machine target torque.

  In the electric drive control method of the present invention, the electric machine target torque representing the target value of the electric machine torque is calculated, the electric machine rotation speed representing the rotation speed of the electric machine, and the electric machine target torque are obtained, Based on the electric machine rotation speed and the electric machine target torque, a target power for driving the electric machine is calculated, and the electric machine rotation is performed by referring to a torque correction map in which a torque correction value of the electric machine target torque is recorded. When the speed is lower than the preset region boundary speed, the electric machine rotates when the electric machine rotation speed is equal to or higher than the region boundary speed based on the torque correction value corresponding to the electric machine rotation speed and the electric machine target torque. The electric machine target torque is corrected based on the torque correction value corresponding to the rotation speed and the target power.

  According to the present invention, in the electric drive control device, the electric machine, the electric machine target torque calculation processing means for calculating the electric machine target torque that represents the target value of the torque of the electric machine, and the rotational speed of the electric machine. The variable power acquisition processing means for acquiring the electric machine rotation speed and the electric machine target torque, and the target power calculation for calculating the target power for driving the electric machine based on the electric machine rotation speed and the electric machine target torque Refer to the processing means and the torque correction map in which the torque correction value of the electric machine target torque is recorded, and when the electric machine rotation speed is lower than a preset region boundary speed, the electric machine rotation speed and the electric machine target torque When the electric machine rotation speed is equal to or greater than the region boundary speed, the electric machine rotation speed and the target Having an electric machine target torque correction processing means for correcting the electric machine target torque based on the torque correction value corresponding to over.

  In this case, when the torque correction map is referred to and the electric machine rotation speed is lower than the preset region boundary speed, the electric machine rotation speed is based on the electric machine rotation speed and the torque correction value corresponding to the electric machine target torque. Is equal to or higher than the region boundary speed, the electric machine target torque is corrected based on the torque correction value corresponding to the electric machine rotation speed and the target power.

  Accordingly, since the torque correction value set in the high speed / high torque region can be used, a torque correction map is not formed unnecessarily, and the memory region is not wasted. As a result, the capacity of the recording apparatus can be reduced accordingly.

  Further, in the high speed region, the line representing the target power is set in parallel with the horizontal axis, but the electric machine target torque becomes smaller as the electric machine rotational speed becomes higher, so that the resolution can be increased. Therefore, the electric machine can be driven with high accuracy.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this case, an electric drive device mounted on an electric vehicle as an electric vehicle, a hybrid vehicle, and the like, and an electric drive control device for operating the electric drive device will be described.

FIG. 1 is a block diagram showing a main part of a drive motor control device according to an embodiment of the present invention, FIG. 3 is a conceptual diagram of an electric drive device according to an embodiment of the present invention, and FIG. 4 is a first diagram in the embodiment of the present invention. FIG. 5 is a diagram showing a second current command value map in the embodiment of the present invention, and FIG. 6 is a diagram showing an operation of the torque correction value calculating unit in the embodiment of the present invention. FIG. 7 is a flowchart showing a virtual torque correction map in the embodiment of the present invention, and FIG. 8 is a diagram showing an actual torque correction map in the embodiment of the present invention. In FIG. 4, the horizontal axis represents the drive motor target torque TM ^* representing the target value of the drive motor torque TM that is the torque of the drive motor 31 as the electric machine, the vertical axis represents the d-axis current command value id ^* , 5, the horizontal axis represents the d-axis current command value id ^* , the vertical axis represents the q-axis current command value iq ^* , the horizontal axis represents the drive motor rotational speed NM, and the vertical axis represents the drive motor target torque TM ^*. 8, the horizontal axis represents the drive motor rotational speed NM, and the vertical axis represents the drive motor target torque TM ^* and the target power P ^* . In this case, the electric motor torque is constituted by the drive motor torque TM, and the electric machine target torque is constituted by the drive motor target torque TM ^* . In this case, the power P represents a work rate or power that is a unit time work, and the target power P ^* represents a target value of the power P.

  In FIG. 3, reference numeral 31 denotes a drive motor. The drive motor 31 is attached to, for example, a drive shaft of an electric vehicle and is rotatably arranged, and is arranged radially outward from the rotor. A stator is provided. The rotor includes a rotor core and permanent magnets arranged at equal pitches at a plurality of locations in the circumferential direction of the rotor core, and a magnetic pole pair is configured by the S pole and the N pole of the permanent magnet. In addition, the stator includes a stator core in which teeth are formed by projecting radially inward at a plurality of locations in the circumferential direction, and U-phase, V-phase, and W-phase coils wound around the teeth. Stator coils 11-13.

  A magnetic pole position sensor 21 is arranged on the output shaft of the rotor as a magnetic pole position detector for detecting the magnetic pole position of the rotor. The magnetic pole position sensor 21 generates a magnetic pole position signal SGθ as a sensor output, It is sent to a drive motor control device 45 as a machine control device. In the present embodiment, the magnetic pole position sensor 21 is used as the magnetic pole position detector. However, a resolver is provided in place of the magnetic pole position sensor 21, and the magnetic pole position signal is detected by the resolver. Can be generated.

  In order to drive the drive motor 31 and drive the electric vehicle, a direct current from the battery 14 is converted into U-phase, V-phase, and W-phase currents Iu, Iv, Iw by an inverter 40 as a current generator. The currents Iu, Iv, and Iw of each phase are supplied to the stator coils 11 to 13, respectively.

  For this purpose, the inverter 40 includes transistors Tr1 to Tr6 as six switching elements, sends the drive signals generated in the drive circuit 51 to the transistors Tr1 to Tr6, and selectively selects the transistors Tr1 to Tr6. By turning on and off, the currents Iu, Iv, and Iw of each phase can be generated. As the inverter 40, a power module such as an IGBT formed by incorporating 2 to 6 switching elements into one package, or an IPM formed by incorporating a drive circuit or the like in the IGBT is used. can do.

  A voltage sensor 15 serving as a voltage detection unit is disposed on the inlet side when supplying current from the battery 14 to the inverter 40. The voltage sensor 15 detects the DC voltage Vdc on the inlet side of the inverter 40, and drives the motor. Send to control device 45. In addition, a battery voltage can also be used as the DC voltage Vdc, and in this case, a battery voltage sensor is disposed in the battery 14 as a voltage detection unit.

  The drive motor 31, the inverter 40, the drive circuit 51, drive wheels (not shown), and the like constitute an electric drive device. Reference numeral 17 denotes a capacitor.

  By the way, since the stator coils 11 to 13 are star-connected, when the current values of two phases of each phase are determined, the current values of the remaining one phase are also determined. Therefore, in order to control the currents Iu, Iv, Iw of each phase, for example, current detection for detecting the U-phase and V-phase currents Iu, Iv on the lead wires of the U-phase and V-phase stator coils 11, 12. Current sensors 33 and 34 are arranged, and the current sensors 33 and 34 send detected currents to the drive motor controller 45 as detected currents iu and iv.

  In addition to a CPU (not shown) that functions as a computer, the drive motor control device 45 is provided with a recording device (not shown) such as a RAM and a ROM for recording data and various programs. First and second current command value maps are formed in the recording apparatus. Note that an MPU can be used instead of the CPU.

  Various programs, data, and the like are recorded in the ROM, but the programs, data, and the like may be recorded on other recording media such as a hard disk provided as an external storage device. it can. In this case, for example, a flash memory is provided in the drive motor control device 45, and the program, data, etc. are read from the recording medium and recorded in the flash memory. Therefore, the program, data, etc. can be updated by exchanging an external recording medium.

  Next, the operation of the electric drive control device will be described.

First, a position detection processing unit (not shown) of the drive motor control device 45 performs a position detection process, reads the magnetic pole position signal SGθ sent from the magnetic pole position sensor 21, and based on the magnetic pole position signal SGθ, reads the magnetic pole position θ. Is detected. The rotational speed calculation processing means of the position detection processing means performs rotational speed calculation processing, and calculates the angular speed ω of the drive motor 31 based on the magnetic pole position signal SGθ. The rotational speed calculation processing means has a drive motor rotational speed NM that is the rotational speed of the drive motor 31 based on the angular speed ω, where p is the number of magnetic poles.
NM = 60 · (2 / p) · ω / 2π
Is also calculated. The electric motor rotation speed is constituted by the drive motor rotation speed NM.

A detection current acquisition processing unit (not shown) of the drive motor control device 45 performs a detection current acquisition process, reads and acquires the detection currents iu and iv, and detects a detection current iw based on the detection currents iu and iv.
iw = -iu-iv
Is obtained by calculating.

A vehicle speed detection processing unit (not shown) of the drive motor control device 45 performs a vehicle speed detection process, detects a vehicle speed V corresponding to the drive motor rotation speed NM based on the drive motor rotation speed NM, and detects it. The vehicle speed V is sent to a vehicle control device (not shown) that controls the entire electric vehicle. Then, the vehicle request torque calculation processing means of the vehicle control device performs vehicle request torque calculation processing, reads the vehicle speed V and the accelerator opening α, and calculates the vehicle request torque TO ^* based on the vehicle speed V and the accelerator opening α. The drive motor target torque calculation processing means as the electric machine target torque calculation processing means of the vehicle control device performs the drive motor target torque calculation processing as the electric machine target torque calculation processing and sets the vehicle request torque TO ^* to Based on this, a drive motor target torque TM ^* is generated and sent to the drive motor controller 45.

Next, a drive motor control processing unit (not shown) of the drive motor control device 45 performs a drive motor control process to obtain a drive motor target torque TM ^* , detected currents iu, iv, iw, a magnetic pole position θ, a DC voltage Vdc, and the like. Based on this, the drive motor 31 is driven.

Therefore, the drive motor control processing means, for adjusting the driving motor target torque TM ^*, driving motor target torque correction unit 44 as an electric machine target torque correction processing means, based on the target drive motor torque TM ^* In order to drive the drive motor 31, a current command value calculation unit 46 as a current command value calculation / adjustment processing unit, a field weakening control processing unit 47 as a field weakening control processing unit, and a voltage command value calculation as a voltage command value calculation processing unit A processing unit 48; a three-phase two-phase conversion unit 49 as a first phase conversion processing unit; and a PWM generator 50 as an output signal generation processing unit. The d-axis is arranged in the direction of the magnetic pole pair in the rotor, and the d-axis Feedback control by vector control calculation is performed on a dq axis model in which the q axis is taken in a direction perpendicular to each other.

The drive motor target torque correction processing unit 44 performs a drive motor target torque correction process, a torque correction value calculation unit 43 as a torque correction value calculation processing means, a subtractor 42 as a torque correction processing means, and upper and lower limits An upper and lower limit processing unit 22 is provided as processing means. When the drive motor target torque TM ^* is sent from the drive motor target torque calculation processing means to the drive motor control device 45, the torque correction value calculation unit 43 performs a torque correction value calculation process, and the drive motor target torque TM ^*. Then, the drive motor rotational speed NM and the DC voltage Vdc are read, and the torque correction value δTM ^* is calculated. The subtractor 42 performs torque correction processing, subtracts the torque correction value δTM ^* calculated by the torque correction value calculation unit 43 from the drive motor target torque TM ^* , performs torque correction, and performs the upper and lower limits. The processing unit 22 performs upper and lower limit processing, and limits the drive motor target torque TM ^* after torque correction to not exceed the upper limit value and the lower limit value.

The current command value calculation unit 46 performs a current command value calculation process, a d-axis current command value calculation unit 53 and a subtractor 55 as a first current command value calculation processing means, and a second current command value. A q-axis current command value calculation unit 54 as a calculation processing unit is provided, and the d-axis current command value calculation unit 53 and the subtractor 55 perform a first current command value calculation process, and obtain a target value of the d-axis current id The d-axis current command value id ^* as the first current command value to be expressed is calculated, and the q-axis current command value calculation unit 54 performs a second current command value calculation process and represents the target value of the q-axis current iq. A q-axis current command value iq ^* as the second current command value is calculated. The d-axis current command value calculation unit 53 constitutes maximum torque control processing means, and the subtractor 55 constitutes current command value adjustment processing means.

  The field weakening control processing unit 47 includes a subtractor 58 as a voltage saturation calculation value calculation processing means, and an integrator 59 as a voltage saturation determination processing means and as an adjustment value calculation processing means, and performs field weakening control processing. If the battery voltage decreases or the drive motor rotational speed NM increases, field weakening control is automatically performed.

The voltage command value calculation processing unit 48 includes a current control unit 61 as current control processing means and a voltage control unit 62 as voltage control processing means in order to perform voltage command value calculation processing, and the d-axis current Based on the command value id ^* and the q-axis current command value iq ^* , the current control unit 61 performs a current control process, and the d-axis voltage command value vd ^* and the q-axis voltage as the first and second axis voltage command values. The command value vq ^* is calculated, and the voltage control unit 62 performs voltage control processing to calculate voltage command values vu ^* , vv ^* , vw ^* as first to third phase voltage command values. The d-axis voltage command value vd ^* , the q-axis voltage command value vq ^*, and the voltage command values vu ^* , vv ^* , vw ^* constitute a voltage command value.

The current command value calculation unit 46 performs a current command value calculation process, reads the drive motor target torque TM ^* , and calculates a d-axis current command value id ^* and a q-axis current command value iq ^* .

For this purpose, the d-axis current command value calculation unit 53 performs a maximum torque control process, reads the drive motor target torque TM ^* limited by the upper and lower limit processing unit 22, and is set in the recording apparatus of FIG. Referring to the first current command value map, the reading drive motor target torque TM ^* corresponding to the d-axis current command value id ^*, and sends to the d-axis current command value id ^* of the subtractor 55.

In this case, in the first current command value map, the d-axis current command value id ^* is set so that the absolute value of the current amplitude command value is minimized in order to achieve the drive motor target torque TM ^* . In the first current command value map, the drive motor target torque TM ^* takes a positive value, whereas the d-axis current command value id ^* takes a negative value, and the drive motor target torque TM ^* is In the case of zero (0), the d-axis current command value id ^* is set to zero, and the d-axis current command value id ^* is set to increase in the negative direction as the drive motor target torque TM ^* increases. The

  In the drive motor 31, a counter electromotive force is generated as the rotor rotates. The higher the drive motor rotational speed NM, the higher the terminal voltage of the drive motor 31, and the terminal voltage exceeds the threshold value. Then, voltage saturation occurs and output by the drive motor 31 becomes impossible.

Therefore, a voltage saturation determination index calculation processing unit (not shown) of the voltage control unit 62 performs voltage saturation determination index calculation processing, and voltage saturation based on the d-axis voltage command value vd ^* and the q-axis voltage command value vq ^*. As a value representing the degree of the voltage saturation determination index m
m = √ (vd ^{* 2} + vq ^{* 2} ) / Vdc
Is sent to the subtractor 58.

The subtractor 58 performs a voltage saturation calculation value calculation process, and calculates a threshold value representing the maximum output voltage of the inverter 40 from the voltage saturation determination index m as a comparison value Vmax.
Vmax = k · Vdc
The voltage saturation calculated value ΔV by subtracting the constant k (0.78 in this embodiment)
ΔV = m−k
Is sent to the integrator 59.

  Subsequently, the integrator 59 performs a voltage saturation determination process and an adjustment value calculation process, integrates the voltage saturation calculated value ΔV at each control timing, calculates an integrated value ΣΔV, and the integrated value ΣΔV takes a positive value. In this case, the integrated value ΣΔV is multiplied by a proportional constant to calculate the adjustment value Δid as a field weakening current for performing field weakening control, set to a positive value, and the voltage saturation calculated value ΔV or the integrated value ΣΔV is When taking a value less than or equal to zero, the adjustment value Δid is set to zero.

The subtractor 55 performs current command value adjustment processing, receives the adjustment value Δid, and adjusts the d-axis current command value id ^* by subtracting the adjustment value Δid from the d-axis current command value id ^*. The d-axis current command value id ^* thus sent is sent to the current control unit 61.

In this case, when the adjustment value Δid takes a zero value, the d-axis current command value id ^* is not substantially adjusted and the field weakening control is not performed. On the other hand, when the adjustment value Δid takes a positive value, the d-axis current command value id ^* is adjusted to increase the value in the negative direction, and field weakening control is performed.

When the d-axis current command value id ^* is calculated in this way, the q-axis current command value calculation unit 54 determines the drive motor target torque TM ^* limited by the upper / lower limit processing unit 22 and the adjustment value Δid. reading, with reference to the same map as FIG. 4, calculates a d-axis current command value id ^* corresponding to the drive motor target torque TM ^*, and adjusts the d-axis current command value id ^* by the adjustment value .DELTA.id. Subsequently, the q-axis current command value calculation unit 54 refers to the second current command value map of FIG. 5 set in the recording device, and the drive motor target torque TM ^* and the adjusted d-axis current command. A q-axis current command value iq ^* corresponding to the value id ^* is calculated, and the q-axis current command value iq ^* is sent to the current control unit 61.

In the second current command value map, the d-axis current command value id ^* increases in the negative direction and the q-axis current command value iq ^* increases in the positive direction as the drive motor target torque TM ^* increases. The smaller the motor target torque TM ^* is, the smaller the d-axis current command value id ^* is set in the negative direction, and the q-axis current command value iq ^* is set in the positive direction. Further, when the drive motor target torque TM ^* is constant, when the d-axis current command value id ^* increases in the negative direction, the q-axis current command value iq ^* decreases in the positive direction.

Therefore, when the adjustment value Δid is zero and the field weakening control is not performed, the adjustment value Δid is zero. For example, as shown in FIG. 5, the q-axis current command value calculation unit 54 calculates the adjustment value Δid. When the d-axis current command value id ^* adjusted by the adjustment value Δid is ida ^* , the q-axis current command value iq ^* is iqa ^* . On the other hand, when the adjustment value Δid takes a positive value and field weakening control is performed, for example, the value of the d-axis current command value id ^* calculated by the q-axis current command value calculation unit 54 is ida ^* . In this case, the adjustment value Δid causes the d-axis current command value id ^* to be a value idb ^* that is larger by the adjustment value Δid in the negative direction, and the q-axis current command value iq ^* is smaller than the value iqa ^{* in the} positive direction. , Value iqb ^* .

The three-phase / two-phase converter 49 performs three-phase / two-phase conversion as the first phase conversion process, reads the magnetic pole position θ, and converts the detected currents iu, iv, and iw into d-axis currents id and q, respectively. The current is converted into the shaft current iq, the d-axis current id and the q-axis current iq are calculated as actual currents, and sent to the current control unit 61. The current control unit 61 receives the d-axis current command value id ^* and the q-axis current command value iq ^* after the field weakening control processing is performed from the subtractor 55 and the q-axis current command value calculation unit 54, and receives the three-phase When the d-axis current id and the q-axis current iq are received from the two-phase converter 49, feedback control is performed.

Therefore, the current control unit 61 calculates a current deviation δid between the d-axis current command value id ^* and the d-axis current id, and a current deviation δiq between the q-axis current command value iq ^* and the q-axis current iq, Proportional control and integral control are performed based on the current deviations δid and δiq.

That is, the current control unit 61 calculates a voltage drop Vzdp representing the voltage command value of the proportional component and a voltage drop Vzdi representing the voltage command value of the integral component based on the current deviation δid, and adds the voltage drops Vzdp and Vzdi. The voltage drop Vzd
Vzd = Vzdp + Vzdi
Is calculated.

The current controller 61 reads the angular velocity ω and the q-axis current iq, and the induced voltage ed induced by the q-axis current iq based on the angular velocity ω, the q-axis current iq, and the q-axis inductance Lq.
ed = ω ・ Lq ・ iq
And the induced voltage ed is subtracted from the voltage drop Vzd to obtain a d-axis voltage command value vd ^* as an output voltage ^.
vd ^* = Vzd-ed
= Vzd-ω · Lq · iq
Is calculated.

Then, the current control unit 61 calculates a voltage drop Vzqp representing the voltage command value of the proportional component and a voltage drop Vzqi representing the voltage command value for the integral term based on the current deviation δiq, and adds the voltage drops Vzqp and Vzqi. The voltage drop Vzq
Vzq = Vzqp + Vzqi
Is calculated.

The current controller 61 reads the angular velocity ω and the d-axis current id, and is induced by the d-axis current id based on the angular velocity ω, the counter electromotive voltage constant MIf, the d-axis current id, and the inductance Ld on the d-axis. Induced voltage eq
eq = ω (Mif + Ld · id)
And the induced voltage eq is added to the voltage drop Vzq, and the q-axis voltage command value vq ^* as the output voltage is calculated ^.
vq ^* = Vzq + eq
= Vzq + ω (Mif + Ld · id)
Is calculated.

Subsequently, a two-phase three-phase conversion unit (not shown) as a second phase conversion processing unit (not shown) of the voltage control unit 62 performs a second phase conversion process, and the d-axis voltage command value vd ^* and the q-axis voltage command. The value vq ^* and the magnetic pole position θ are read, the d-axis voltage command value vd ^* and the q-axis voltage command value vq ^* are converted into voltage command values vu ^* , vv ^* , vw ^* , and the voltage command values vu ^* , vv ^*. , Vw ^* is sent to the PWM generator 50.

The PWM generator 50 performs output signal generation processing, and based on the voltage command values vu ^* , vv ^* , vw ^* and the DC voltage Vdc of each phase, the d-axis current command value id ^* and the q-axis current. Pulse width modulation signals Mu, Mv, Mw of each phase having a pulse width corresponding to the command value iq ^* are generated as output signals and sent to the drive circuit 51.

  The drive circuit 51 receives the pulse width modulation signals Mu, Mv, Mw of each phase, generates six drive signals, and sends the drive signals to the inverter 40. The inverter 40 switches the transistors Tr1 to Tr6 to generate currents Iu, Iv, Iw of the respective phases based on the pulse width modulation signals Mu, Mv, Mw, and the currents Iu, Iv, Iw of the respective phases. Is supplied to the stator coils 11 to 13 of the drive motor 31.

In this manner, torque control is performed based on the drive motor target torque TM ^* , and the drive motor 31 is driven to run the electric vehicle.

Meanwhile, reading the first corresponding from the current command value map to the driving motor target torque TM ^* d-axis current command value id ^*, q-axis corresponding to the d-axis current command value id ^* from the second electric current command value map When the current command value iq ^* is read and the drive motor 31 is driven, it may not be possible to generate the drive motor torque TM according to the drive motor target torque TM ^* . Therefore, as described above, the torque correction value calculation processing means reads the drive motor target torque TM ^* , the drive motor rotational speed NM, and the DC voltage Vdc, and refers to the torque correction map set in the recording apparatus. The torque correction value δTM ^* is calculated. The subtractor 42 performs torque correction processing, and subtracts the torque correction value δTM ^* calculated by the torque correction value calculation unit 43 from the drive motor target torque TM ^* to perform torque correction. Accordingly, the drive motor 31 is driven based on the d-axis current command value id ^* and the q-axis current command value iq ^* corresponding to the corrected drive motor target torque TM ^* .

  Next, the torque correction map will be described.

  In this case, since the electric drive device is mounted on an electric vehicle, a hybrid vehicle, or the like, the DC voltage Vdc constantly varies with traveling. Therefore, as shown in FIGS. 8 and 9, the torque correction map includes a plurality of maps mk (k = 1, 2,..., R), and each map mk has a lower limit value and an upper limit value of the DC voltage Vdc. Are uniformly divided into a plurality of portions, and are formed at predetermined intervals.

Further, in each map mk, O is the origin, and Ni (i = 1, 2,..., P) is a predetermined number by dividing the upper limit value of the drive motor rotational speed NM and zero evenly. A line Tj (j = 1, 2,..., Q) set for each interval and representing the drive motor rotation speed NM is an area boundary speed Nsk (k = 1) in which the drive motor rotation speed NM is set for each map mk. 2,..., R) in the low speed region lower than the theoretical upper limit value of the drive motor target torque TM ^* and zero, the drive motor is set at predetermined intervals by equally dividing the upper limit value into zero. A line representing the target torque TM ^* , Pj (j = 1, 2,..., S) represents each drive motor in the high speed region where the drive motor rotational speed NM is not less than the region boundary speed Nsk and not more than the upper limit value. Drive motor target at each rotational speed NM The maximum value of the torque TM ^*, i.e., the target power P ^* maximum value corresponding to the maximum drive motor target torque TM ^* max, i.e., by evenly divided between the maximum target power P ^* max and zero plurality , A line that represents the target power P ^* , set for each predetermined interval, and at each point where each line Ni intersects the lines Tj and Pj, that is, at each intersection, the drive motor rotational speed NM and the drive motor target The correction value δTM ^* corresponding to the torque TM ^* is
−β1 ≦ δTM ^* ≦ + β2 (β1, β2> 0)
Is set and recorded as follows. In this case, the region boundary speed Nsk is the highest drive motor rotation speed NM among the drive motor rotation speeds NM taking the maximum value of the theoretical drive motor target torque TM ^* . The line Tj forms an equal torque curve, and the line Pj forms an equal power curve. The output limit is expressed by the maximum drive motor target torque TM ^* max.

In the present embodiment, only the portion where the drive motor target torque TM ^* takes a positive value is shown, but the portion where the drive motor target torque TM ^* takes a negative value is set similarly.

By the way, the target power P ^* consumed when the drive motor 31 is driven is:
P ^* = NM ・ TM ^*
It can be expressed as Therefore, when the target power P ^* is represented by a line Pj, when the drive motor target torque TM ^* is taken on the vertical axis in the virtual torque correction map of FIG. 7, the line Pj has a pattern that approximates an isotorque line. Thus, the drive motor target torque TM ^* can be lowered as the drive motor rotational speed NM increases.

On the other hand, in the actual torque correction map of FIG. 8, the coordinate system is different between the low speed region and the high speed region. In the low speed region, the drive motor rotational speed NM is plotted on the horizontal axis and the drive motor is plotted on the vertical axis. It is set in a coordinate system in which the target torque TM ^* is taken, and in the high speed region, the drive motor rotational speed NM is set in the horizontal axis, and the coordinate system in which the target power P ^* is taken on the vertical axis.

In this case, the maximum drive motor target torque TM ^* max is set to be constant in the low speed region, and the maximum target power P ^* max is set to be constant in the high speed region, so that the lines Tj and Pj are parallel to the horizontal axis.

  Next, the operation of the torque correction value calculation unit 43 will be described.

In this case, when the drive motor rotational speed NM and the drive motor target torque TM ^* are specified, the variable acquisition processing unit (not shown) of the torque correction value calculation unit 43 performs the variable acquisition process, and the drive motor target torque TM ^*. The drive motor rotation speed NM and the DC voltage Vdc are read, and a region determination processing unit (not shown) of the torque correction value calculation unit 43 performs a region determination process, depending on whether the drive motor rotation speed NM is lower than the region boundary speed Nsk. Determine if it belongs to the low speed region. When the drive motor rotational speed NM is equal to or higher than the region boundary speed Nsk and belongs to the high speed region, target power calculation processing means (not shown) of the torque correction value calculation unit 43 performs target power calculation processing, and the drive motor target The target power P ^* is calculated by multiplying the torque TM ^* and the drive motor rotational speed NM.

Subsequently, a torque correction value acquisition processing unit (not shown) of the torque correction value calculation unit 43 performs a torque correction value acquisition process, and reads out the torque correction value δTM ^* at the intersection of the lines Ni and Tj in the low speed region. In the region, the torque correction value δTM ^* at the intersection of the lines Ni and Pj is read out.

An interpolation processing means (not shown) of the torque correction value calculation unit 43 performs interpolation processing, performs interpolation according to the read torque correction value δTM ^* , and in this embodiment performs linear interpolation, and drives the motor rotation speed. calculating the torque correction value? Tm ^* corresponding to the NM and drive motor target torque TM ^*.

Thus, in the present embodiment, torque correction is performed based on the drive motor rotational speed NM and the drive motor target torque TM ^* in the low speed region, and based on the drive motor rotational speed NM and the target power P ^* in the high speed region. Therefore, the torque correction value δTM ^* set in the high speed / high torque region can be used. Therefore, the torque correction map is not formed unnecessarily, and the memory area is not wasted. As a result, the capacity of the recording apparatus can be reduced accordingly.

Further, in the high speed region, each line Pj is set in parallel to the horizontal axis, but the drive motor target torque TM ^* becomes smaller as the drive motor rotation speed NM increases as shown in FIG. Can be high. Therefore, the drive motor 31 can be driven with high accuracy.

Next, a flowchart will be described.
Step S1: Read the drive motor target torque TM ^* .
Step S2 Read the drive motor rotational speed NM.
Step S3 Read DC voltage Vdc.
Step S4: It is determined whether or not the drive motor rotational speed NM is lower than the region boundary speed Nsk. If the drive motor rotation speed NM is lower than the area boundary speed Nsk, the process proceeds to step S6. If the drive motor rotation speed NM is equal to or higher than the area boundary speed Nsk, the process proceeds to step S5.
Step S5: Power P is calculated.
Step S6: The torque correction value δTM ^* is read out.
Step S7: Interpolation processing is performed and the processing is terminated.

  In the present embodiment, the case where the drive motor 31 is driven is described. However, when the present invention drives a generator as an electric machine, the drive motor as a first electric machine, and the second This can be applied to driving a generator as an electric machine.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

It is a block diagram which shows the principal part of the drive motor control apparatus in embodiment of this invention. It is a figure which shows the conventional torque correction map. It is a conceptual diagram of the electric drive device in embodiment of this invention. It is a figure which shows the 1st electric current command value map in embodiment of this invention. It is a figure which shows the 2nd electric current command value map in embodiment of this invention. It is a flowchart which shows operation | movement of the torque correction value calculation part in embodiment of this invention. It is a figure which shows the virtual torque correction map in embodiment of this invention. It is a figure which shows the actual torque correction map in embodiment of this invention.

Explanation of symbols

31 drive motor 40 inverter 43 torque correction value calculation unit 44 drive motor target torque correction processing unit 51 drive circuit

Claims (5)

  An electric machine, electric machine target torque calculation processing means for calculating an electric machine target torque representing a target value of torque of the electric machine, an electric machine rotation speed representing the rotation speed of the electric machine, and the electric machine target torque Variable acquisition processing means to be acquired; target power calculation processing means for calculating target power for driving the electric machine based on the electric machine rotation speed and electric machine target torque; and torque correction value of the electric machine target torque Referring to the torque correction map in which the electric machine rotation speed is lower than the preset region boundary speed, the electric machine rotation is performed based on the electric machine rotation speed and the torque correction value corresponding to the electric machine target torque. When the speed is equal to or higher than the region boundary speed, the electric machine is based on the torque correction value corresponding to the electric machine rotation speed and the target power. Electric drive control apparatus characterized by comprising an electric machine target torque correction processing means for correcting the target torque.   The torque correction map is a coordinate system of the electric machine rotation speed and the electric machine target torque in a low speed region where the electric machine rotation speed is lower than the region boundary speed, and in the high speed region where the electric machine rotation speed is equal to or higher than the region boundary speed. The electric drive control device according to claim 1, wherein the electric drive control device is formed by a coordinate system of a rotation speed and a target power.   The electric drive control device according to claim 1, wherein the torque correction map is formed for each DC voltage.   The electric drive control device according to any one of claims 1 to 3, wherein the region boundary speed is the highest electric machine rotation speed among the electric machine rotation speeds that take the maximum value of the electric machine target torque. An electric machine target torque representing a target value of the electric machine torque is calculated, an electric machine rotation speed representing the rotation speed of the electric machine, and the electric machine target torque are obtained, and the electric machine rotation speed and the electric machine target torque are obtained. And calculating a target power for driving the electric machine, referring to a torque correction map in which the torque correction value of the electric machine target torque is recorded, and the electric machine rotation speed from a preset region boundary speed Based on the torque correction value corresponding to the electric machine rotation speed and the electric machine target torque, when the electric machine rotation speed is equal to or higher than the region boundary speed, the torque correction corresponding to the electric machine rotation speed and the target power. An electric drive control method comprising correcting an electric machine target torque based on a value.

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