JP4896562B2 - Electric drive control device and electric drive control method - Google Patents

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 disposed as an electric machine in an electric vehicle such as an electric vehicle or a hybrid vehicle is rotatably disposed and includes a magnetic pole pair made up of N-pole and S-pole permanent magnets. A rotor, a stator that is disposed radially outward from the rotor, and that includes U-phase, V-phase, and W-phase stator coils, and the like.

  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 electric machine 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 electric machine 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, and the like, 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, Calculate d-axis voltage command value and q-axis voltage command value based on deviation between d-axis current and d-axis current command value, deviation between q-axis current and q-axis current command value, and parameters of drive motor or generator Like to do.

In the current command value map, a d-axis current command corresponding to the drive motor target torque representing the target value of the drive motor torque, or the generator target torque representing the target value of the generator torque, the DC voltage, and the angular velocity. Value and q-axis current command value are recorded. The electric motor torque is constituted by the drive motor torque and the generator torque, and the electric machine target torque is constituted by the drive motor target torque and the generator target torque. 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).
Japanese Patent Laid-Open No. 5-130710

  However, in the conventional electric machine control device, the d-axis current command value and the q-axis current command value corresponding to the drive motor target torque or the generator target torque are read from the current command value map, and the drive motor or the generator is When driven, it may not be possible to generate a drive motor torque according to the drive motor target torque or a generator torque according to the generator target torque. In that case, in an electric vehicle that is driven by driving only the drive motor, even if the accuracy of the generated drive motor torque is low, the driver operates the accelerator pedal to move the electric vehicle at a constant speed. However, in an electric vehicle that is driven by driving a drive motor and a generator, if the drive motor torque and the generator torque cannot be balanced, the drive motor torque and the generator Torque cannot be generated with high accuracy.

  The present invention solves the problems of the conventional electric machine control device, can generate electric machine torque according to the electric machine target torque, and can drive the electric machine with high accuracy, and An object is to provide an electric drive control method.

  Therefore, in the electric drive control device of the present invention, the electric machine, electric machine target torque calculation processing means for calculating an electric machine target torque representing a target value of the torque of the electric machine, and the torque of the electric machine target torque The electric machine target torque for correcting the electric machine target torque with reference to the torque correction map in which the correction value is recorded and based on the torque correction value corresponding to the electric machine rotation speed representing the rotation speed of the electric machine and the electric machine target torque Correction processing means.

  The torque correction map is formed by equally dividing the maximum torque of the electric machine in the 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, It is formed by equally dividing the maximum output of the electric machine.

  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 representing the target value of the torque of the electric machine, and the torque of the electric machine target torque The electric machine target torque for correcting the electric machine target torque with reference to the torque correction map in which the correction value is recorded and based on the torque correction value corresponding to the electric machine rotation speed representing the rotation speed of the electric machine and the electric machine target torque Correction processing means.

  The torque correction map is formed by equally dividing the maximum torque of the electric machine in the 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, It is formed by equally dividing the maximum output of the electric machine.

  In this case, the electric machine target torque is corrected with the torque correction map, and the electric machine is driven based on the first current command value and the second current command value corresponding to the corrected electric machine target torque. Therefore, the electric machine torque according to the electric machine target torque can be generated.

  Further, the torque correction map is formed by equally dividing the maximum torque of the electric machine 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, Since it is formed by equally dividing the maximum output of the electric machine, the maximum value of the electric machine target torque is set so as to decrease as the electric machine rotational speed increases in the high speed region. Therefore, an equally divided torque correction map can be formed over the entire electric machine rotation speed, and the resolution can be increased. As a result, 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. A drive motor control device as an electric machine control device arranged in the electric drive control 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. 2 is a conceptual diagram of an electric drive device according to an embodiment of the present invention, and FIG. 3 is a first diagram in the embodiment of the present invention. FIG. 4 is a diagram showing a second current command value map in the embodiment of the present invention, and FIG. 5 is a diagram showing a torque correction map in the embodiment of the present invention. In FIG. 3, the horizontal axis represents the drive motor target torque TM ^* representing the target value of the drive motor torque TM which is the torque of the drive motor 31 as the electric machine, the vertical axis represents the d-axis current command value id ^* , 4, the horizontal axis indicates the d-axis current command value id ^* , the vertical axis indicates the q-axis current command value iq ^* , and in FIG. 5, the horizontal axis indicates the drive motor rotational speed NM that is the rotational speed of the drive motor 31. The drive motor target torque TM ^* is taken on the shaft. 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 FIG. 2, 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. Note that the rotational speed calculation processing means has a drive motor rotational speed NM 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. 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 drive motor target torque calculation processing as the electric machine target torque calculation processing, and is based on the vehicle required torque TO ^*. The drive motor target torque TM ^* is calculated 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. The 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

  By the way, in the drive motor 31, a counter electromotive force is generated as the rotor rotates. However, as the drive motor rotational speed NM increases, the terminal voltage of the drive motor 31 increases, and the terminal voltage becomes a threshold value. If the threshold value is exceeded, 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 the 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, the reference to the same map as FIG. 3, which is set in the recording apparatus, calculates a d-axis current command value id ^* corresponding to the drive motor target torque TM ^*, the the d-axis current command value id ^* Adjustment is made according to the adjustment value Δid. Subsequently, the q-axis current command value calculation unit 54 refers to the second current command value map of FIG. 4 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, as the drive motor target torque TM ^* increases, 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. 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. 4, the q-axis current command value calculation unit 54 calculates the adjustment value Δid. When the value of the d-axis current command value id ^* adjusted by the adjustment value Δid is ida ^* , the value of 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. It converts into the axial current iq, calculates the d-axis current id and the q-axis current iq as actual currents, and sends them 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 the voltage drop Vzqp representing the voltage command value of the proportional component and the 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, the drive motor target torque TM ^* is corrected with the torque correction map, and the drive motor 31 is controlled 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 ^*. I try to drive it.

  In an electric vehicle that is driven by driving only the drive motor 31, even if the accuracy of the generated drive motor torque TM is low, the driver can operate the electric vehicle by operating the accelerator pedal. In an electric vehicle that can be driven at a high speed, the drive motor 31 is driven as a first electric machine by driving a generator (not shown) as a second electric machine. Since it is necessary to balance the torque TM and the generator torque, it is necessary to generate the drive motor torque TM and the generator torque with high accuracy.

Therefore, in that case, the drive motor target torque TM ^* and the generator target torque are corrected by the torque correction map, and the drive motor 31 and the generator are driven based on the corrected drive motor target torque TM ^* and the generator target torque. Is preferred.

  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, the torque correction map includes a plurality of maps mk (k = 1, 2,..., R), and each map mk equally divides the lower limit value and the upper limit value of the DC voltage Vdc into a plurality. By this, it is formed at predetermined intervals.

In FIG. 5, O is the origin, and Ni (i = 1, 2,..., P) is divided into a plurality of equal parts between the upper limit value of the drive motor rotational speed NM and zero at predetermined intervals. A line Tj (j = 1, 2,..., Q) that is set and represents the drive motor rotational speed NM is an area boundary speed Nsk (k = 1, 2,..., Q) where the drive motor rotational speed NM is set for each map mk. .., R) In a lower low speed region, the drive motor rotational speed NM is set at predetermined intervals by equally dividing the theoretical upper limit value of the drive motor target torque TM ^* into zero. In the high speed region where the region boundary speed Nsk is equal to or higher than the region boundary speed Nsk and equal to or lower than the upper limit value, the maximum drive motor target torque TM ^* max representing the maximum value of the drive motor target torque TM ^* for each drive motor rotational speed NM and zero In between This is a line that represents the drive motor target torque TM ^* that is set at predetermined intervals by dividing into equal parts. The upper limit of the target drive motor torque TM ^* on the theory, represents the maximum torque of the drive motor 31, the maximum value of the driving motor target torque TM ^* of each drive motor rotation speed NM, the maximum drive motor 31 Represents the output.

Then, each line Ni, at each intersection where Tj intersect, the torque correction value? Tm ^* corresponding to the drive motor rotation speed NM and drive motor target torque TM ^*,
−β1 ≦ δTM ^* ≦ + β2 (β1, β2> 0)
Is set and recorded as follows. In this case, β1 and β2 are preset values, and the region boundary speed Nsk is the highest drive motor speed NM among the drive motor speeds NM taking the maximum value of the theoretical drive motor target torque TM ^*. NM.

Therefore, when the drive motor rotational speed NM and the drive motor target torque TM ^* are specified, the torque correction value δTM ^* is read from the torque correction map, and the torque correction value δTM ^* is subtracted from the drive motor target torque TM ^*. To be corrected. Then, the drive motor 31 is driven based on the corrected drive motor target torque TM ^* . The drive motor rotation speed NM between the intersections and the torque correction value δTM ^{* at} the drive motor target torque TM ^* between the intersections are calculated by interpolating the torque correction value δTM ^* at each intersection.

  By the way, when the drive motor 31 is driven, the output does not reach an upper limit value in the low speed region due to characteristics, so that the maximum value of the generated drive motor torque TM can be made constant, but in the high speed region, Since the output becomes the upper limit value, the maximum value of the drive motor torque TM cannot be set to a constant value, and becomes lower as the drive motor rotational speed NM increases.

Therefore, when actually setting the drive motor target torque TM ^*, in accordance with the characteristics of the drive motor 31, in the low speed region, the maximum drive motor target torque TM ^* max of each drive motor rotation speed NM constant, 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, even when the torque correction map is formed, the maximum drive motor target torque TM ^* max is set so as to be constant in the low speed region so that it decreases as the drive motor rotational speed NM increases in the high speed region. ing.

  Therefore, the line Tj forms an equal torque curve in the low speed region and an equal output curve in the high speed region. In the low speed region, the maximum torque area is configured and the torque area is represented, and in the high speed region, the maximum output area is configured and the output limit is represented.

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.

  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 rotational speed NM and the DC voltage Vdc are acquired by reading.

The torque correction value acquisition processing means (not shown) of the torque correction value calculation unit 43 performs torque correction value acquisition processing, refers to the map mk corresponding to the DC voltage Vdc, and calculates the torque correction value at the intersection of the lines Ni and Tj. Interpolation processing means (not shown) of the torque correction value calculation unit 43 reads δTM ^* , performs interpolation processing, and interpolates between the intersections according to the read torque correction value δTM ^* . In the present embodiment, linear Interpolation is performed to calculate a torque correction value δTM ^* corresponding to the drive motor rotational speed NM and the drive motor target torque TM ^* .

Thus, the drive motor target torque TM ^* is corrected with the torque correction map, and the drive motor is 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 ^*. Since 31 is driven, it is possible to generate the drive motor torque TM according to the drive motor target torque TM ^* .

In forming the torque correction map, in the present embodiment, the maximum drive motor target torque TM ^* max is constant in the low speed region, and is decreased as the drive motor rotational speed NM increases in the high speed region. Since it is set, an equally divided torque correction map can be formed over the entire area, and the resolution can be increased. Therefore, the drive motor 31 can be driven with high accuracy.

  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.

  Further, in the high speed region, the higher the drive motor rotational speed NM, the shorter the interval between the lines Tj, so that the drive motor torque TM can be finely corrected.

  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 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 figure which shows the 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 (4)

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;
With reference to the torque correction map in which the torque correction value of the electric machine target torque is recorded, the electric machine target torque based on the electric machine rotation speed representing the rotation speed of the electric machine and the torque correction value corresponding to the electric machine target torque Electric machine target torque correction processing means for correcting
The torque correction map is formed by equally dividing the maximum torque of the electric machine 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. An electric drive control device formed by equally dividing the maximum output of the motor. The electric drive control device according to claim 1, wherein the torque correction map is formed for each DC voltage on the inlet side of the inverter .   The electric drive control device according to claim 1, wherein the region boundary speed is the highest electric machine rotation speed among electric machine rotation speeds that take a maximum value of the electric machine target torque. Calculate the electric machine target torque that represents the target value of the electric machine torque,
With reference to the torque correction map in which the torque correction value of the electric machine target torque is recorded, the electric machine target torque based on the electric machine rotation speed representing the rotation speed of the electric machine and the torque correction value corresponding to the electric machine target torque As well as
The torque correction map is formed by equally dividing the maximum torque of the electric machine 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 method is characterized by being formed by equally dividing the maximum output of the motor.

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