JP2015142445A - Control device of motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a motor capable of suppressing the degradation of controllability of a rotation speed of the motor even when a command torque of the motor is limited.SOLUTION: A control device 11 applied to an MG 30 that is a drive source of a vehicle comprises: drive means for calculating a command torque of the MG 30 on the basis of a target rotation speed of the MG 30 and driving the MG 30 on the basis of the calculated command torque; and suppression means for suppressing the target rotation speed in accordance with a limit value of the command torque. The drive means includes following means for calculating a following torque from the amount of change of the target rotation speed per prescribed time and inertia of a rotor including the MG 30. The command torque is calculated based on the following torque calculated by the following means.

Description

  The present invention relates to a motor control device that is a travel drive source of a vehicle.

  2. Description of the Related Art In recent years, automobiles equipped with a motor that is a travel drive source have become widespread, such as EV cars and HV cars. As such a traveling motor control device, an apparatus for controlling the driving of a motor based on a target rotational speed has been proposed. For example, in Patent Document 1, the command torque is calculated based on the target rotation speed, and the calculated command torque is output to the motor, whereby the rotation speed of the motor is brought close to the target rotation speed.

JP 2009-143360 A

  In the control device that controls the driving of the motor based on the target rotational speed, if the command torque calculated based on the target rotational speed is limited, the control apparatus cannot follow the target rotational speed. For this reason, the deviation between the target rotational speed and the actual rotational speed increases, and the actual rotational speed may overshoot beyond the target rotational speed, or the increase in the actual rotational speed may stop before reaching the target rotational speed. . That is, when the command torque of the motor is limited, there is a problem that the controllability of the rotational speed of the motor is lowered.

  In view of the above circumstances, it is a primary object of the present invention to provide a motor control device capable of suppressing a decrease in controllability of the rotational speed of a motor even when the command torque of the motor is limited.

  In order to solve the above problems, the present invention is a control device applied to a motor that is a driving source of a vehicle, and calculates a command torque of the motor based on a target rotational speed of the motor. Drive means for driving the motor based on the command torque; and suppression means for suppressing the target rotational speed in accordance with a limit value of the command torque.

  According to the present invention, the command torque of the motor is calculated based on the target rotational speed of the motor, and the motor is driven based on the calculated command torque. Thereby, the actual rotational speed of the motor is controlled to the target rotational speed.

  Here, in the configuration in which the motor is driven based on the command torque, when the command torque is limited due to various factors, when the target rotation speed is larger than the motor rotation speed that can be realized by the limited command torque, The actual rotational speed of the motor cannot follow the target rotational speed. As a result, when the rotational speed of the motor is controlled by feedback control, the actual rotational speed of the motor may overshoot. Further, when the rotation speed of the motor is controlled by feedforward control, the increase in the rotation speed may stop before the actual rotation speed of the motor reaches the target rotation speed.

  Therefore, the target rotational speed is suppressed according to the limit value of the command torque. That is, the target rotational speed is suppressed so as to approach the realizable rotational speed. As a result, the deviation between the target rotational speed and the actual rotational speed is suppressed, and the actual rotational speed follows the target rotational speed. Therefore, even when the command torque of the motor is limited, it is possible to suppress a decrease in controllability of the motor rotation speed.

The figure which shows schematic structure of a vehicle system. The control block diagram which concerns on 1st Embodiment. The figure which shows the time change of the request | requirement rotation speed which concerns on 1st Embodiment, target rotation speed, real rotation speed, and command torque. The flowchart which shows the process sequence which calculates target rotation speed. (A) Required rotational speed, (b) Target rotational speed when rate is not limited, (c) Rate value, (d) Minimum selected target rotational speed, (e) Time variation of output target rotational speed. The control block diagram which concerns on 2nd Embodiment. The figure which shows the time change of the request | requirement rotation speed which concerns on 2nd Embodiment, target rotation speed, real rotation speed, and command torque. The control block diagram which concerns on other embodiment. The control block diagram which concerns on other embodiment. The control block diagram which concerns on a reference example. The control block diagram which concerns on a reference example. The figure which shows the time change of the request | requirement rotation speed which concerns on a reference example, target rotation speed, real rotation speed, and command torque.

  Hereinafter, embodiments in which a motor control device is applied to a traveling motor mounted on a hybrid vehicle will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the same reference numerals is used.

(First embodiment)
First, a schematic configuration of a hybrid vehicle system according to the present embodiment will be described with reference to FIG. The hybrid vehicle according to the present embodiment includes HVECU 10, MC 11, ENGECU 12, engine 20, MG 30, transmission 40, and wheels 50.

  The engine 20 and the MG 30 (motor) are vehicle driving sources. A clutch CL1 (transmission means) that connects and disconnects the rotation shaft 31 of the MG 30 and the output shaft 21 of the engine 20 is connected to the rotation shaft 31 of the MG 30 on the engine 20 side. In addition, a clutch CL <b> 2 that engages and disconnects the rotation shaft 31 of the MG 30 and the input shaft 41 of the transmission 40 is connected to the rotation shaft 31 on the transmission 40 side of the MG 30.

  The MG 30 is a motor generator having functions of both an electric motor and a generator. When MG 30 operates as an electric motor, MG 30 operates by receiving power supply from battery 33 via inverter 32. Further, when the MG 30 operates as a generator, the MG 30 is rotated by the driving force transmitted from the engine 20 or the axle 51 to generate power. The electric power generated by the MG 30 is supplied to the battery 33 via the inverter 32.

  When the MG 30 operates as an electric motor, torque generated by the MG 30 is input to the input shaft 41 of the transmission 40 via the clutch CL2, and is shifted by the transmission 40 and transmitted to the left and right wheels 50. Torque generated by the engine 20 is input to the input shaft 41 of the transmission 40 via the clutches CL1, MG30, and the clutch CL2, and is shifted by the transmission 40 and transmitted to the left and right wheels 50. Therefore, the left and right wheels 50 are driven by at least one of the torque generated by the MG 50 and the torque generated by the engine 20.

  The HVECU 10 (hybrid control device), the MC 11 (motor control device), and the ENGECU 12 (engine control device) are each configured as a microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and are stored in the ROM. Execute various programs.

  The HVECU 10 is an ECU higher than the MC 11 and the ENGECU 12 (upstream from the user's request), and performs bidirectional communication with each of the MC 11 and the ENGECU 12. The HVECU 10 calculates the requested values of the control amounts of the MG 30 and the engine 20 based on a user request input from the user interface, for example, a detection signal such as the operation amount of the accelerator pedal of the user, and outputs the calculated values to the MC 11 and the ENGECU 12, respectively.

  When MC 11 receives the required rotational speed that is the required value of the control amount from HVECU 10, MC 11 controls inverter 32 to control the rotational speed of MG 30 to the required rotational speed. The rotational speed control of the MG 30 by the MC 11 will be described in detail later. When MC 11 receives a start request for engine 20 from HVECU 10, MC 11 controls inverter 32 to cause MG 30 to generate a driving force necessary for starting engine 20. In addition, the rotation speed of MG30 means the rotation speed of MG30 per minute.

  The MC 11 is a sensor for detecting the operating state of the MG 30 (not shown), such as a rotation angle sensor that detects the rotation speed of the MG 30, a voltage sensor that detects the drive voltage of the MG 30, and a temperature sensor that detects the temperature of the magnet of the MG 30. ) Receive the detected value. And MC11 calculates the value of the maximum torque which MG30 can output based on the present driving | running state of MG30.

  Further, the MC 11 receives the current state of the battery 33 from a battery ECU (not shown) that controls the battery 33. Specifically, the MC 11 receives an SOC (State of Charge), temperature, maximum current, and the like of the battery 33 from the battery ECU. MC 11 calculates the maximum torque value that can be output by MG 30 based on the maximum output of battery 33 set from the current state of battery 33. Specifically, the value of the maximum torque is calculated from the equation: maximum torque = maximum output of battery 33 / number of rotations of MG30 × K1. K1 is a unit conversion coefficient (60 / (2π)).

  Then, the MC 11 calculates the smaller value of the maximum torque calculated based on the operating state of the MG 30 and the maximum torque calculated based on the maximum output of the battery 33 as the maximum torque of the MG 30. Set to value. Note that the maximum torque value is a positive value in the direction of increasing the rotational speed of the MG 30, and a negative value in the direction of decreasing the rotational speed.

  When the ENGECU 12 receives a control value request value, for example, a combustion torque request value, from the HVECU 10, the ENGECU 12 controls the fuel injection by the fuel injection valve provided in each cylinder in order to control the combustion torque to the required value. The combustion control is performed.

  Next, the rotational speed control of the MG 30 by the MC 11 will be described. First, a reference example of the rotational speed control of the MG 30 will be described with reference to FIGS. 10 and 12. FIG. 10 is a reference example of a control block diagram of rotational speed control by FB (feedback) control.

  In the reference example, when the required rotational speed is received from the HVECU 10, a low-pass filter process is performed to calculate the target rotational speed. Specifically, since the processing speed of the MC 11 is generally faster than the required speed of the HVECU 30, the change over time of the required rotational speed input to the MC 11 is stepped. For this reason, the target rotational speed is calculated by dulling the rapid change in the required rotational speed and removing the noise component. Then, a PI control torque for performing PI control is calculated from the deviation between the calculated target rotation speed and the actual rotation speed of the MG 30. Subsequently, when the value of the PI control torque is larger than the value of the maximum torque of the MG 30, the value of the PI control torque is limited to the value of the maximum torque, and the maximum torque is set as the command torque. On the other hand, when the value of the PI control torque is equal to or less than the value of the maximum torque of the MG 30, the PI control torque is set as the command torque.

  When the command torque is not limited, the actual rotational speed follows the target rotational speed, as shown in FIGS. On the other hand, when the command torque is limited, as shown in FIGS. 12C and 12D, the actual rotational speed does not follow the target rotational speed. In a period in which the increase speed of the target rotation speed is high, the increase in the actual rotation speed cannot follow the increase in the target rotation speed, and the deviation between the target rotation speed and the actual rotation speed is large. When the increase speed of the target rotational speed becomes small, the actual rotational speed exceeds the target rotational speed and overshoots. This is because even if the amount of change in the target rotational speed per predetermined time becomes small, the proportional term and integral term of PI control, especially the integral term, do not become small immediately. Thus, when the command torque is limited, overshoot occurs in the rotational speed control by the FB control, and the controllability of the rotational speed of the MG 30 may be reduced.

  Therefore, in this embodiment, in order to suppress a decrease in the controllability of the rotational speed of the MG 30, the target rotational speed is suppressed according to the limit value of the command torque, that is, the maximum torque value of the MG 30 together with the low-pass filter process. Perform rate limit processing. FIG. 2 is a control block diagram of the rotational speed control by the FB control according to the present embodiment.

  First, when the required rotational speed is received from the HVECU 10, low-pass filter processing is performed on the amount of change in the required rotational speed per predetermined time, and the amount of change in the target rotational speed per predetermined time is calculated (S10). Subsequently, based on the limit value of the command torque, an allowable rate value that is a change amount of the rotation speed that can be realized per predetermined time is calculated. If the change amount of the target rotation speed calculated in S10 is larger than the allowable rate value, the target rotation speed is calculated so that the change amount of the target rotation speed becomes the allowable rate value (S20). And the process of S10 and S20 is repeated and a target rotation speed is calculated sequentially.

  As a result, the speed of increase of the target rotational speed, that is, the amount of change per predetermined time is smaller than the target rotational speed (see FIGS. 3A and 3B) when the torque is not suppressed according to the limit value of the command torque. (See FIGS. 3C and 3D). Specifically, the amount of change in the target rotational speed per predetermined time is the amount of change in the rotational speed per predetermined time that can be realized with the limit value of the command torque, that is, the maximum torque of the MG 30. Note that the processing of S10 and S20 will be described in detail later.

  Subsequently, a PI control torque for performing PI control is calculated from the deviation between the target rotational speed suppressed according to the limit value of the command torque and the actual rotational speed (S40). Subsequently, when the value of the PI control torque calculated in S40 is larger than the value of the maximum torque of the MG 30, the value of the PI control torque is limited to the value of the maximum torque, and the inverter is set with the value of the maximum torque as the command torque. To 32. On the other hand, if the value of the PI control torque calculated in S40 is less than or equal to the maximum torque value of MG 30, the PI control torque calculated in S40 is output to the inverter 32 as a command torque (S50).

  In this way, by suppressing the target rotational speed according to the limit value of the command torque, as shown in FIGS. 3C and 3D, even when the command torque is limited, the actual rotational speed is the target rotational speed. The overshoot by FB control is suppressed following the number. That is, the controllability of the rotational speed of the MG 30 is improved as compared with the reference example.

  The low-pass filter process (S10) and the rate limit process (S20) correspond to the suppression means, and the PI control (S40) and the torque upper / lower limit restriction process (S50) correspond to the drive means.

  Next, a processing procedure for calculating the target rotational speed in accordance with the limit value of the command torque will be described with reference to the flowchart of FIG. The MC 11 repeatedly executes this process at a predetermined time interval, and i represents the number of loops. The final value of the LPF (i) value calculated in the loop at time i becomes the target rotation speed at time i.

First, the output value when the required rotation speed is input to the low-pass filter,
LPF (i) = LPF (i−1) + {InpSig−LPF (i−1)} × (Ts / Tc)
(S11). InpSig is the requested rotational speed at time i which is the input value of LPF, LPF (i−1) is the LPF value calculated in the previous loop, Ts is the LPF calculation cycle, and Tc is the LPF filter time constant. That is, {InpSig-LPF (i-1)} × (Ts / Tc) is the difference between the current required rotational speed and the previously calculated target rotational speed, that is, the rotation per predetermined time calculated based on the required rotational speed. This corresponds to the amount of change in the number obtained by low pass filter processing.

  In the next processing of S12 to S15, when the amount of change in the rotational speed is equal to or less than the allowable rate value that is the amount of rotational speed change that can be realized per predetermined time, the LPF (i) value calculated in S11 is set to i. The target rotational speed at the time. On the other hand, if the amount of change in the rotational speed is greater than the allowable rate value, the rate limit process is performed to update the LPF (i) value.

  Next, it is determined whether or not the LPF (i) value calculated in S11 is larger than a value obtained by adding a positive allowable rate value to the previous LPF (i-1) value. That is, it is determined whether or not {InpSig-LPF (i-1)} × (Ts / Tc) is larger than a positive allowable rate value (S12).

  Here, the allowable rate value is calculated from the equation: allowable rate value = maximum torque of MG30 / inertia × Ts × K2. The inertia is an inertia of the rotating body including the MG 30. When the clutch CL1 is engaged, the MG 30 and the engine 20 are rotating bodies. When the clutch CL1 is disconnected, only the MG 30 is a rotating body. Therefore, the clutch CL1 is engaged and disconnected. To change the inertia value. Specifically, the inertia is set to a larger value when the clutch CL1 is engaged than when the clutch CL1 is disconnected. Ts is a calculation cycle of the target rotational speed, and the allowable rate value is converted into a value per calculation cycle. K2 is a unit conversion coefficient (60 / (2π)). If the maximum torque is a positive value, the allowable rate value is a positive value, and if the maximum torque is a negative value, the allowable rate value is a negative value.

  When {InpSig-LPF (i-1)} × (Ts / Tc) is larger than the positive allowable rate value (S12: YES), the LPF (i) value is set to a positive value for LPF (i-1). It is updated to a value obtained by adding the allowable rate value (S13). On the other hand, if {InpSig-LPF (i-1)} × (Ts / Tc) is equal to or less than the positive allowable rate value (S12: NO), the value of LPF (i) is not updated and the next processing is performed. move on.

  Next, it is determined whether the LPF (i) value is smaller than a value obtained by adding a negative allowable rate value to the previous LPF (i-1) value. That is, it is determined whether the magnitude of {InpSig-LPF (i-1)} × (Ts / Tc), which is a negative change amount, is larger than the magnitude of the negative allowable rate value (S14).

  When the magnitude of {InpSig-LPF (i-1)} × (Ts / Tc) is larger than the magnitude of the negative allowable rate value (S14: YES), the LPF (i) value is changed to LPF (i− It is updated to a value obtained by adding a negative allowable rate value to 1) (S15). On the other hand, if the magnitude of {InpSig-LPF (i-1)} × (Ts / Tc) is equal to or less than the negative allowable rate value (S14: NO), the value of LPF (i) is not updated and the next Proceed to the process.

  Subsequently, the loop count i is updated to i + 1 (S16). This process is repeatedly executed at predetermined time intervals, and the value of LPF (i), which is the target rotational speed, is sequentially calculated.

  The target rotational speed calculated by the processing procedure of the flowchart of FIG. 4 is indicated by a broken line (e) in FIG. Further, the required rotational speed is indicated by a solid line (a), the target rotational speed calculated only by the low-pass filter process is indicated by a dotted line (b), and the positive allowable rate value is indicated by a one-dot chain line (c).

  As a method for calculating the target rotational speed, a method of performing a minimum selection between the target rotational speed calculated by low-pass filtering the required rotational speed and the target rotational speed calculated by rate limiting the required rotational speed is also conceivable. The target rotational speed calculated by such a method is as shown by a solid line (d). That is, in a period (0 to 0.13 s) where the target rotational speed calculated by the rate limit process is smaller than the target rotational speed by the low-pass filter process, the target rotational speed calculated by the rate limit process is final. This is the target speed. In a period (0.13 to 0.2 s) in which the target rotational speed calculated by the low-pass filter process is smaller than the target rotational speed calculated by the rate limit process, the target rotational speed calculated by the low-pass filter process is the final Target rotation speed.

  As described above, when the target rotational speed calculated by the minimum select shifts from the rate limit processing value to the low-pass filter processing value, the rising slope of the target rotational speed, that is, the amount of change per predetermined time changes suddenly. This sudden change of the inclination causes overshoot of the target rotational speed. Therefore, if the target rotational speed is calculated by the minimum select, even if the target rotational speed is suppressed according to the limit value of the command torque, the controllability of the rotational speed of the MG 30 may be reduced.

  Further, as a method for calculating the target rotational speed, a method of performing a low-pass filter process after rate limiting the required rotational speed is also conceivable. When the target rotational speed is calculated by such a method, the time change of the target rotational speed is limited more than necessary, and the responsiveness to the required rotational speed may be reduced.

  On the other hand, in the processing procedure of the flowchart shown in FIG. 4, at a predetermined time, the value obtained by low-pass filtering the amount of change in the rotational speed calculated based on the required rotational speed and the allowable rate value are minimum-selected. The target speed is calculated. As a result, since the target rotational speed that is smoothly changed can be obtained while limiting the time change of the target rotational speed to the minimum necessary, the decrease in the controllability of the rotational speed of the MG 30 is suppressed.

  According to 1st Embodiment described above, there exist the following effects.

  The command torque of MG30 is calculated based on the target rotation speed of MG30, and MG30 is driven based on the calculated command torque. At this time, the target rotational speed is suppressed according to the limit value of the command torque. That is, the target rotational speed is suppressed so as to approach the rotational speed that can be realized by the limit value of the command torque. As a result, the deviation between the target rotational speed and the actual rotational speed is suppressed, and the actual rotational speed follows the target rotational speed. Therefore, even when the command torque of the motor is limited, it is possible to suppress a decrease in controllability of the motor rotation speed.

  A rate value is calculated based on the value obtained by dividing the command torque limit value by the inertia. The calculated rate value becomes a limit value of the amount of change per predetermined time of the realizable target rotation speed. When the amount of change in the target rotational speed per predetermined time is larger than the rate value, the target rotational speed is suppressed so that the amount of change becomes the rate value. Thereby, even when the command torque of MG30 is restrict | limited, the fall of the controllability of the rotation speed of MG30 can be suppressed.

  In a state where the rotating shaft 31 of the MG 30 and the output shaft 21 of the engine 20 are fastened, the MG 30 and the engine 20 are rotating bodies, and the rotating shaft 31 of the MG 30 and the output shaft 21 of the engine 20 are disconnected. Then, only MG30 becomes a rotating body. Therefore, the inertia value is different between the state in which the MG 30 and the engine 20 are fastened and the state in which the engine 20 is disconnected, so that the inertia value is switched. Thereby, the controllability of the rotation speed of MG30 can be improved.

  The smaller torque value of the torque value calculated based on the operating state of the MG 30 and the torque value calculated based on the maximum output of the battery 33 that supplies power to the MG 30 can be output by the MG 30 Set to maximum torque. And the command torque of MG30 is restrict | limited to the value of the maximum torque of MG30. Thereby, even if it is a case where the command torque of MG30 is restrict | limited based on both the present driving | running state of MG30 and the maximum output of the battery 33, it can suppress to the rotation speed which can implement | achieve the target rotation speed of MG30.

(Second Embodiment)
Next, the motor control device according to the second embodiment will be described while referring to differences from the first embodiment. In the second embodiment, the rotational speed control of the MG 30 is mainly performed by FF (feed forward) control.

  First, a reference example of the rotational speed control of the MG 30 by FF control will be described with reference to FIGS. 11 and 12. FIG. 11 is a reference example of a control block diagram of the rotational speed control, and is a block diagram in which the rotational speed control is performed mainly by FF control.

  In the reference example, when the required rotational speed is received from the HVECU 10, a low-pass filter process is performed to calculate the target rotational speed. Subsequently, target rotational speed tracking correction processing is performed. Specifically, a follow-up torque for causing the target speed to follow is calculated based on the calculated target speed. Further, a PI control torque for performing PI control is calculated from the deviation between the calculated target rotational speed and the actual rotational speed. Here, the gain of the PI control is reduced, the rotational speed control is performed mainly by the target rotational speed tracking correction process that is the FF control, and the fine adjustment is performed in the PI control that is the FB control. Subsequently, when the torque value obtained by adding the follow-up torque and the PI control torque is larger than the maximum torque value of the MG 30, the command torque is limited to the maximum torque value.

  The change over time in the actual rotational speed when the command torque is limited to the maximum torque is shown by a solid line (FF control) in FIG. Since the command torque is limited during a period during which the increase speed of the target rotational speed is large, the actual rotational speed does not increase to the target rotational speed. When the increase speed of the target rotational speed is reduced, the follow-up torque is reduced, and the actual rotational speed is moderately increased with a deviation from the target rotational speed. Note that since the gain of PI control is small, the actual rotational speed cannot be increased rapidly by PI control.

  Therefore, in the second embodiment, in order to suppress a decrease in the controllability of the rotational speed of the MG 30, the rate limit process is performed together with the low-pass filter process in the same manner as the first embodiment, and the target is set according to the command torque limit. Suppresses the rotation speed. That is, in the second embodiment, the rotational speed control is performed by adding the target rotational speed tracking correction process to the first embodiment.

  The rotational speed control of the MG 30 according to the second embodiment will be described with reference to FIGS. FIG. 6 is a control block diagram of the rotational speed control according to the present embodiment, and is a block diagram for performing rotational speed control mainly by FF control.

  First, when the required rotational speed is received from the HVECU 10, a low-pass filter process (S10) and a rate limit process (S20) are performed to calculate a target rotational speed. The method for calculating the target rotational speed is the same as in the first embodiment. Thereby, the amount of change per predetermined time of the target rotational speed is suppressed to be smaller than the target rotational speed (see FIGS. 7A and 7B) when the command torque is not limited (see FIG. 7C). ), (D)).

Subsequently, a target rotational speed tracking correction process is performed based on the calculated target rotational speed, and a tracking torque is calculated (S30). For more information,
Follow-up torque = follow-up torque is calculated from the equation: change amount of target rotation speed per calculation cycle / Ts × inertia × K3. Ts is a calculation cycle, and the amount of change in the target rotational speed is converted per unit time (1 sec). As in the first embodiment, the inertia value is switched according to whether the clutch CL1 is engaged or disconnected. K3 is a unit conversion coefficient (2π / 60). Further, a PI control torque for performing PI control is calculated from the deviation between the calculated target rotational speed and the actual rotational speed (S40).

  In the first embodiment, tracking to the target rotational speed, disturbance torque compensation, hardware variations, and the like are all handled by PI control, so the load of PI control is large. In contrast, in the second embodiment, follow-up control to the target rotational speed is performed by target rotational speed follow-up correction processing that is FF control, and fine adjustment such as disturbance torque compensation is performed by PI control that is FB control. As a result, the PI control load is reduced, so that the PI control gain can be reduced.

  Subsequently, when the torque value obtained by adding the PI control torque value calculated in S40 to the follow-up torque value calculated in S30 is larger than the maximum torque value of MG30, the command torque is limited to the maximum torque. Then, the command torque is output to the inverter 32. On the other hand, if the torque value obtained by adding the PI control torque value calculated in S40 to the follow torque value calculated in S30 is equal to or less than the maximum torque value of MG30, the follow torque and the PI control torque are added. The torque is output to the inverter 32 as a command torque (S50).

  The low-pass filter process (S10) and the rate limit process (S20) correspond to the suppression means, and the target rotation number tracking process (S30) corresponds to the tracking means. Further, the target rotational speed follow-up process (S30), the PI control (S40), and the torque upper / lower limit limiting process (S50) correspond to drive means.

  Thus, even when the command torque is limited by adding the rate limit process, the actual rotational speed follows the target rotational speed as shown in FIGS. 7C and 7D, and the actual rotational speed. Has risen to the required rotational speed. That is, the controllability of the rotational speed of the MG 30 is improved as compared with the reference example. Furthermore, there is no overshoot of the actual rotational speed, and more stable rotational speed control is realized than in the first embodiment.

  According to 2nd Embodiment described above, there exist the following effects.

  A follow-up torque for following the target speed is calculated from the amount of change in the target speed per predetermined time and inertia, and a command torque is calculated based on the calculated follow-up torque. Thereby, the actual rotational speed can be made to follow the target rotational speed in a stable state, and the controllability of the rotational speed of the motor can be improved.

  -By adding the target rotational speed tracking correction process, the burden of PI control is reduced, and the gain of PI control is reduced. By reducing the gain of the FB control, the rotational speed control of the MG 30 can be stabilized.

(Other embodiments)
In each of the above embodiments, PID control may be performed instead of PI control.

  Although the controllability of the rotational speed may be lower than when PI control is turned on, as shown in FIG. 8, in the second embodiment, the rotational speed control of the MG 30 is performed only by the FF control except for the PI control. You may do it. Even in this case, the actual rotational speed follows the target rotational speed by suppressing the target rotational speed in accordance with the limit value of the command torque.

  As shown in FIG. 9, an observer (load compensation) process may be added in the second embodiment. The observer process is a process for estimating and compensating for disturbance, and calculates the compensation torque from the deviation between the command torque and the torque calculated from the actual rotational speed. The calculated compensation torque is added to the added value of the follow-up torque and the PI control torque. As factors of the disturbance, the driving state of the engine 20, the gear ratio of the transmission 40, and the like can be cited. In the first embodiment, an observer process may be added.

  In situations where the torque value based on the current operating state of the MG is smaller than the torque value based on the maximum output of the battery 33, such as when the temperature of the MG 30 is high, the maximum torque value that the MG 30 can output is The torque value calculated based on the current operating state of the MG 30 may be used. Thus, even if the command torque of MG30 is limited based on the current operating state of MG30, the target rotational speed of MG30 can be suppressed to a realizable rotational speed.

  In a situation where the torque value based on the maximum output of the battery 33 is smaller than the torque value based on the current operating state of the MG 30 such as when the temperature is low, the maximum torque value that can be output by the MG 30 is The torque value calculated based on the 33 maximum output may be used. Thus, even if the command torque of MG 30 is limited based on the maximum output of battery 33, the target rotation speed of MG 30 can be suppressed to a realizable rotation speed.

  A smoothing process such as a moving average process may be performed instead of the low-pass filter process.

  -You may apply a motor control apparatus to control of the motor of the EV vehicle which is not equipped with the engine.

  10 ... HVECU, 11 ... MC, 20 ... engine, 30 ... MG, 33 ... battery, CL1, CL2 ... clutch.

Claims (8)

A control device (11) applied to a motor (30) which is a travel drive source of a vehicle,
Driving means for calculating a command torque of the motor based on the target rotational speed of the motor, and driving the motor based on the calculated command torque;
Suppression means for suppressing the target rotational speed in accordance with a limit value of the command torque;
A motor control device comprising: The drive means includes follow-up means for calculating follow-up torque from the amount of change in the target rotational speed per predetermined time and the inertia of the rotating body including the motor,
The motor control device according to claim 1, wherein the command torque is calculated based on the follow-up torque calculated by the follow-up means.   The suppressing means calculates an allowable rate value based on a value obtained by dividing the limit value by an inertia of a rotating body including the motor, and a change amount per predetermined time of the target rotational speed is greater than the allowable rate value. The motor control device according to claim 1, wherein the target rotational speed is suppressed so that the amount of change becomes the allowable rate value. The rotation shaft (31) of the motor is provided with a transmission means (CL1) for fastening and cutting the rotation shaft of the motor and the output shaft (21) of the engine (20).
4. The motor control device according to claim 2, wherein the inertia value is switched between a state in which the transmission unit is fastened and a state in which the transmission unit is disconnected. The limit value is a value of the maximum torque that the motor can output,
The motor control device according to claim 1, wherein the maximum torque is a value calculated based on a current operation state of the motor. The limit value is a value of the maximum torque that the motor can output,
The motor control device according to any one of claims 1 to 4, wherein the maximum torque is a value calculated based on a maximum output of a battery (33) that supplies electric power to the motor. The limit value is a value of the maximum torque that the motor can output,
The maximum torque is a smaller value of a value calculated based on an operating state of the motor and a value calculated based on a maximum output of a battery that supplies power to the motor. The motor control device according to any one of 4.   The motor control device according to claim 1, wherein the command torque is calculated based on a deviation between the target rotation speed and an actual rotation speed of the motor.

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