JP6421710B2 - Inverter control device - Google Patents

Description

  The present invention relates to an inverter control device that is applied to a vehicle including only a rotating electrical machine as an in-vehicle main machine and is electrically connected to the rotating electrical machine.

  As this type of control device, as can be seen in the following Patent Document 1, only a rotating electrical machine disposed in the vicinity of the driving wheel or in the vicinity of the driving wheel is used as an in-vehicle main machine, and the driving wheel is directly driven by this rotating electrical machine. What is applied to an electric vehicle is known. Specifically, when it is determined that a failure has occurred in the rotating electrical machine while the vehicle is running, the control device stops the control of the rotating electrical machine until the stop of the vehicle is confirmed by operating the inverter. When it is determined that the stop of the rotating electrical machine is requested after the stop of the vehicle is confirmed, the control device determines again the failure of the rotating electrical machine in a state where the operation of the vehicle is blocked by the brake.

JP 2012-191751 A

  In a vehicle including only a rotating electrical machine as an in-vehicle main machine, when an abnormality relating to the driving of the rotating electrical machine occurs, the driving force of the vehicle is lost when the driving of the rotating electrical machine is stopped. For this reason, there is a concern that the vehicle cannot be properly retracted after the drive of the rotating electrical machine is stopped.

  The main object of the present invention is to provide an inverter control device capable of appropriately retreating a vehicle even when an abnormality relating to driving of a rotating electrical machine occurs.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  The present invention is applied to a vehicle (10) having only a rotating electrical machine (11) as an in-vehicle main machine, and the output torque of the rotating electrical machine or a parameter having a positive correlation with the output torque is used as a controlled variable, and the controlled variable is used as the controlled variable. An inverter operating unit for operating the inverter (12) electrically connected to the rotating electrical machine to control to a target value; and an abnormality determining unit for determining whether an abnormality relating to driving of the rotating electrical machine has occurred. The rotating electrical machine is actually operated on condition that the rotating electrical machine is driven for traveling of the vehicle over a period in which it is determined that an abnormality has occurred during the traveling of the vehicle. A torque reduction unit that forcibly reduces the output torque of the motor and a state in which it is determined that an abnormality has occurred by the abnormality determination unit continues for a threshold time. Characterized in that it and a drive stop unit that stops the driving of the.

  In the above invention, when the vehicle is running, when the abnormality determination unit determines that an abnormality relating to the driving of the rotating electrical machine that is the in-vehicle main unit has continued for a threshold time, the driving of the rotating electrical machine is stopped. . For this reason, it is possible to secure a power source for retreating the vehicle as compared with the configuration in which the driving of the rotating electrical machine is immediately stopped when it is determined that an abnormality relating to the driving of the rotating electrical machine has occurred.

  When the vehicle is evacuated while the abnormality is occurring, the vehicle speed is lowered. Here, when the vehicle speed is low, there may be a problem that vibration generated in the vehicle becomes larger than when the vehicle speed is high. The generation factor of the vibration includes torque fluctuation of the rotating electrical machine. There is a concern that the driver may feel uneasy when the vibration of the vehicle increases under the circumstances where the retreat traveling should be performed. Therefore, in the above invention, the actual rotating electrical machine is driven on the condition that the rotating electrical machine is driven for traveling of the vehicle over a period in which it is determined that an abnormality has occurred while the vehicle is traveling. The output torque is forcibly reduced. By reducing the output torque, the torque fluctuation of the rotating electrical machine can be reduced. For this reason, it is possible to avoid giving the driver anxiety in a situation where the evacuation is to be performed.

  As described above, according to the above-described invention, it is possible to avoid giving the driver anxiety in a situation where the vehicle should be retreated while securing a power source for retreating the vehicle. Thereby, the vehicle can be appropriately retreated.

1 is an overall configuration diagram of an in-vehicle system according to a first embodiment. The block diagram which shows a torque control process. The flowchart which shows the procedure of a fail safe process. The figure which shows the relationship between a vehicle speed and a torque limiting coefficient. The figure which shows the relationship between a voltage phase, a motor torque, and a motor rotational speed. The figure which shows the relationship between a motor rotational speed and a motor maximum torque. The figure which shows the relationship between a vehicle speed and vehicle sensitivity. The time chart which shows an example of the fail safe process in the case of transfering from temporary abnormality determination to this abnormality determination. The time chart which shows an example of the fail safe process in the case of transfering from temporary abnormality determination to normal control. The block diagram which shows the torque control process concerning 2nd Embodiment. The figure which shows the relationship between a vehicle speed and a feedback gain.

(First embodiment)
Hereinafter, a first embodiment in which a control device according to the present invention is applied to an electric vehicle including only a rotating electric machine as an in-vehicle main machine will be described with reference to the drawings.

  As shown in FIG. 1, the vehicle 10 according to the present embodiment includes a single motor generator 11, an inverter 12, an EVECU 20, and an INVECU 30. In the present embodiment, a permanent magnet synchronous machine is used as the motor generator 11, and more specifically, an IPMSM that is a salient pole machine is used.

  The vehicle 10 includes drive wheels 13, driven wheels 14, an electric power steering device 15, and a brake device 16. An output shaft 11 a coupled to the rotor of the motor generator 11 is mechanically connected to the drive wheel 13 via a differential gear 17. Here, in this embodiment, the transmission is not provided in the power transmission path that connects the output shaft 11a and the drive wheels 13. In the present embodiment, the driving wheel 13 is a front wheel and the driven wheel 14 is a rear wheel.

  The electric power steering device 15 includes a handle for operating the steering angle of the drive wheel 13 as a steering wheel, and a steering motor. The steering motor generates a steering force that assists the steering operation force.

  The brake device 16 includes a master back for assisting the driver to depress the brake pedal and an electric pump, and applies a braking force to the drive wheel 13 and the driven wheel 14. The electric pump generates a negative pressure for braking in the master back.

  An inverter 12 is electrically connected to each phase of the stator winding of the motor generator 11. The inverter 12 includes three sets of serially connected bodies of upper arm switches Sup, Svp, Swp and lower arm switches Sun, Svn, Swn. A battery 18 as a DC power source is connected to a series connection body of the upper arm switch and the lower arm switch.

  The U phase of the stator winding is connected to the connection point between the U phase upper and lower arm switches Sup and Sun. The V phase of the stator winding is connected to the connection point between the V phase upper and lower arm switches Svp and Svn. The W phase of the stator winding is connected to a connection point between the W phase upper and lower arm switches Swp and Swn. Incidentally, in the present embodiment, voltage controlled semiconductor switching elements are used as the switches Sup to Swn, and more specifically, IGBTs are used. The freewheel diodes Dup, Dvp, Dwp, Dun, Dvn, and Dwn are connected in antiparallel to the switches Sup, Svp, Swp, Sun, Svn, and Swn.

  The vehicle 10 includes a voltage sensor 21, a phase current sensor 22, a rotation angle sensor 23, a temperature sensor 24, and a speed sensor 25. The voltage sensor 21 detects the voltage of the battery 18 input to the inverter 12. The phase current sensor 22 detects at least two-phase current among the respective phase currents in the three-phase fixed coordinate system flowing through the motor generator 11. The rotation angle sensor 23 detects the electrical angle of the motor generator 11. In the present embodiment, a resolver is used as the rotation angle sensor 23.

  The temperature sensor 24 uses a switch constituting the inverter 12 as a temperature detection target. In the present embodiment, one of the switches Sup to Swn, which is assumed to have the highest temperature when the inverter 12 is driven, is a temperature detection target. The speed sensor 25 may be any sensor that can detect the vehicle speed. For example, an ABS wheel speed sensor can be used.

  The EV ECU 20 is an electronic control device that controls vehicle control. EVECU 20 includes a target value setting unit that sets a target torque Trq of motor generator 11 based on the depression amount of the accelerator pedal by the driver. The EVECU 20 outputs the set target torque Trq and the vehicle speed Vs detected by the speed sensor 25 to the INVECU 30.

  The INVECU 30 is a lower electronic control device than the EVECU 20. The detection values of the voltage sensor 21, the phase current sensor 22, the rotation angle sensor 23, and the temperature sensor 24 are input to the INVECU 30. In the present embodiment, INVECU 30 includes an inverter operation unit.

  Subsequently, torque control of the motor generator 11 according to the present embodiment will be described with reference to FIG. In the present embodiment, the current feedback control for controlling the output torque of the motor generator 11 to the target torque Trq is performed by controlling the current flowing through the motor generator 11 to the command current.

  Based on the phase current detected by the phase current sensor 22 and the electrical angle θ detected by the rotation angle sensor 23, the two-phase conversion unit 30a converts the U, V, and W phase currents in the three-phase fixed coordinate system, Conversion into d-axis current Idr and q-axis current Iqr in the dq coordinate system, which is a two-phase rotating coordinate system. The speed calculation unit 30b calculates the electrical angular speed ω of the motor generator 11 based on the electrical angle θ.

  The temperature coefficient setting unit 30c variably sets the temperature coefficient Kt for correcting the target torque Trq based on the temperature detected by the temperature sensor 24 (hereinafter referred to as “element temperature TD”). The temperature coefficient setting unit 30c is a processing unit for reducing the target torque Trq when the element temperature TD is high in order to protect the switches Sup to Swn constituting the inverter 12 from overheating. In the present embodiment, the temperature coefficient setting unit 30c sets the temperature coefficient Kt to 1 when it is determined that the element temperature TD is equal to or lower than the first specified temperature T1 higher than 0. In this case, the target torque Trq is not limited. When it is determined that the element temperature TD is higher than the first specified temperature T1 and lower than the second specified temperature T2, the temperature coefficient setting unit 30c sets the temperature coefficient Kt to be smaller as the element temperature TD is higher. When the temperature coefficient setting unit 30c determines that the element temperature TD is equal to or higher than the second specified temperature T2, the temperature coefficient setting unit 30c sets the temperature coefficient Kt to 0. In this case, target torque Trq is set to 0, and driving of motor generator 11 is stopped.

  The temperature multiplier 30d multiplies the target torque Trq set by the EVECU 20 by the temperature coefficient Kt and outputs the result. The fail safe unit 30e corrects the target torque Trq set by the EVECU 20 based on the torque limit coefficient Kv. The fail safe unit 30e outputs the corrected target torque “(1-Kv) × Trq”. The processing performed by the fail safe unit 30e will be described in detail later. In the present embodiment, the temperature coefficient setting unit 30c and the temperature multiplication unit 30d correspond to a temperature correction unit.

  The selection unit 30f outputs the smaller one of the output value “Kt × Trq” of the temperature multiplication unit 30d and the output value “(1-Kv) × Trq” of the fail safe unit 30e as the target correction torque Ttgt. The command current setting unit 30g sets the d and q axis command currents Id * and Iq * based on the target correction torque Ttgt output from the selection unit 30f.

  The d-axis deviation calculating unit 30h calculates the d-axis current deviation ΔId as a value obtained by subtracting the d-axis current Idr from the d-axis command current Id * set by the command current setting unit 30g. The q-axis deviation calculating unit 30i calculates the q-axis current deviation ΔIq as a value obtained by subtracting the q-axis current Iqr from the q-axis command current Iq * set by the command current setting unit 30g.

  The d-axis command voltage calculation unit 30j calculates the d-axis command voltage Vd * as an operation amount for performing feedback control of the d-axis current Idr to the d-axis command current Id * based on the d-axis current deviation ΔId. In this embodiment, as shown in the following equation (eq1), the d-axis command voltage Vd * is calculated by proportional-integral control using the d-axis current deviation ΔId as an input.

上式（ｅｑ１）において、Ｋｐは比例ゲインを示し、Ｋｉは積分ゲインを示す。

In the above equation (eq1), Kp represents a proportional gain, and Ki represents an integral gain.

  The q-axis command voltage calculation unit 30k calculates the q-axis command voltage Vq * as an operation amount for feedback-controlling the q-axis current Iqr to the q-axis command current Iq * based on the q-axis current deviation ΔIq. In the present embodiment, as shown in the following equation (eq2), the q-axis command voltage Vq * is calculated by proportional-integral control with the q-axis current deviation ΔIq as an input.

なお本実施形態では、ｄ軸指令電圧算出部３０ｊにおけるフィードバックゲインＫｐ，Ｋｉと、ｑ軸指令電圧算出部３０ｋにおけるフィードバックゲインＫｐ，Ｋｉとを同一に設定している。

In the present embodiment, the feedback gains Kp, Ki in the d-axis command voltage calculation unit 30j and the feedback gains Kp, Ki in the q-axis command voltage calculation unit 30k are set to be the same.

  The three-phase conversion unit 301 is based on the d and q-axis command voltages Vd * and Vq *, the voltage detected by the voltage sensor 21 (hereinafter referred to as “power supply voltage VINV”), and the electrical angle θ in the dq coordinate system. The d and q axis command voltages Vd * and Vq * are converted into U, V, and W phase command voltages Vu *, Vv *, and Vw * in a three-phase fixed coordinate system. In the present embodiment, the U, V, and W phase command voltages Vu *, Vv *, and Vw * are sinusoidal or rectangular waveforms that are 120 degrees out of phase with each other in electrical angle.

  The operation unit 30m is configured to turn on / off the switches Sup, Sun, Svp, Svn, Swp, and Swn based on the phase command voltages Vu *, Vv *, and Vw * output from the three-phase conversion unit 301. The signals gup, gun, gvp, gvn, gwp, gwn are generated. The operation unit 30m outputs the generated operation signals gup, gun, gvp, gvn, gwp, gwn to the switches Sup, Sun, Svp, Svn, Swp, Swn. Here, the operation signals gup to gwn may be generated based on a magnitude comparison between a carrier signal such as a triangular wave signal and each phase command voltage Vu *, Vv *, Vw *, for example. The drive signals gup, gvp, gwp on the upper arm side and the corresponding drive signals gun, gvn, gwn on the lower arm side are complementary to each other. Therefore, the upper arm switches Sup, Svp, Swp and the corresponding lower arm switches Sun, Svn, Swn are alternately turned on.

  Next, the fail safe process performed by the fail safe unit 30e will be described. The fail safe portion 30e is provided for appropriately retreating the vehicle 10 when an abnormality relating to driving of the motor generator 11 occurs.

  In FIG. 3, the procedure of the process which the fail safe part 30e performs is shown. This process is repeatedly executed by the fail safe unit 30e.

  In this series of processing, first, in step S10, it is determined whether an abnormality relating to driving of the motor generator 11 has occurred. In the present embodiment, the current detection value abnormality in which the phase current detected by the phase current sensor 22 deviates from the actual phase current, and the angle in which the electrical angle θ detected by the rotation angle sensor 23 deviates from the actual electrical angle. It is determined whether any one of the detected value abnormality and the detected temperature value abnormality in which the element temperature TD deviates from the actual switch temperature has occurred. Each of the current detection value abnormality, the angle detection value abnormality, and the temperature detection value abnormality includes an abnormality of the sensor itself and a disconnection abnormality of a signal line that electrically connects the sensor and the INVECU 30. In this embodiment, the process of this step corresponds to an abnormality determination unit.

  In the subsequent step S11, a temporary abnormality is determined, and the temporary abnormality flag Fa is switched from 0 to 1. Further, as shown in FIG. 4, the torque limit coefficient Kv for correcting the target torque Trq is set larger as the vehicle speed Vs detected by the speed sensor 25 is lower. Specifically, when the vehicle speed Vs is 0, the torque limit coefficient Kv is set to 1, and when the vehicle speed Vs is a first vehicle speed higher than 0 (for example, 10 km / h), the torque limit coefficient Kv is a first smaller than 1. Set to a coefficient (eg, 0.9). When the vehicle speed Vs is a second vehicle speed (for example, 30 km / h) higher than the first vehicle speed, the torque limit coefficient Kv is set to a second coefficient (for example, 0.6) smaller than the first coefficient, and the vehicle speed Vs is In the case of a third vehicle speed (for example, 80 km / h) higher than the second vehicle speed, the torque limit coefficient Kv is set to a third coefficient (for example, 0.2) smaller than the second coefficient. When the vehicle speed Vs is equal to or lower than the third vehicle speed and the vehicle speed Vs is a value other than 0, the first vehicle speed, and the second vehicle speed, the torque limiting coefficient Kv is set by linear interpolation. Then, the target torque Trq is forcibly reduced by inputting the set torque limit coefficient Kv into “(1−Kv) × Trq”. In the present embodiment, when the vehicle speed Vs is higher than the third speed, the torque limit coefficient Kv is set to zero. In this case, the target torque Trq is not limited in the fail safe unit 30e.

  Incidentally, when no abnormality is detected in the angle detection value, the vehicle speed may be calculated based on the electrical angle θ detected by the rotation angle sensor 23, and the torque limit coefficient Kv may be set using the calculated vehicle speed.

  The torque limit coefficient Kv setting process corresponds to a torque reduction unit, and avoids giving the driver anxiety when the vehicle 10 is driven to evacuate in a situation where an abnormality determination related to the driving of the motor generator 11 is made. Process.

  Under a situation where an abnormality relating to driving of the motor generator 11 occurs, the vibration generated in the vehicle 10 increases as the vehicle speed decreases. In the present embodiment, the factors that increase the vibration include factors relating to the motor generator 11 and factors relating to the vehicle 10.

  First, factors related to the motor generator 11 will be described. FIG. 5 shows the relationship between the voltage phase that is the phase of the output voltage vector of inverter 12 and the output torque of motor generator 11. Here, the output voltage vector is defined by the d-axis voltage and the q-axis voltage, and the voltage phase is, for example, an angle formed by the positive direction of the d-axis in the dq coordinate system and the output voltage vector. In the present embodiment, the voltage phase is defined in the dq coordinate system as a positive direction counterclockwise with respect to the d axis.

  As shown in FIG. 5, the maximum value of the output torque of the motor generator 11 increases as the rotational speed Nm of the motor generator 11 decreases. This is because, as shown in FIG. 6, the maximum value of the output torque of the motor generator 11 decreases as the rotational speed Nm increases. However, as shown in FIG. 5, the voltage phase at which the output torque reaches the maximum value does not change greatly regardless of the rotational speed Nm. For this reason, the amount of change in the output torque with respect to the change in voltage phase increases as the rotational speed Nm decreases.

  Therefore, when an angle detection value abnormality occurs, the influence of the deviation between the detected electrical angle θ and the actual electrical angle on the output torque increases as the rotational speed Nm decreases. When the influence on the output torque is increased, the fluctuations of the d and q axis current deviations ΔId and ΔIq are increased, and as a result, the fluctuation of the output torque is increased. Even when a current detection value abnormality occurs, the fluctuations in the output torque increase due to the large fluctuations in the d and q axis current deviations ΔId and ΔIq. When the fluctuation of the output torque is increased, the vibration of the vehicle 10 is increased, which gives the driver anxiety.

  When a temperature detection value abnormality occurs, for example, the element temperature TD changes between the first specified temperature T1 and the second specified temperature T2, and the temperature coefficient Kt changes. As a result, the output value of the temperature multiplier 30d varies greatly. Also in this case, the target correction torque Ttgt fluctuates greatly, giving the driver anxiety.

  Next, factors related to the vehicle will be described. FIG. 7 shows the relationship between the vehicle speed and the vehicle sensitivity when the driving force of the vehicle 10 is made the same by making the output torque of the motor generator 11 the same. Here, the vehicle sensitivity is, for example, the acceleration of the vehicle 10 with respect to the force input to the vehicle body from the road surface via the wheels. The acceleration includes at least one of accelerations in the vertical direction, the horizontal direction, and the front-rear direction of the vehicle 10. As illustrated, the vehicle 10 has a characteristic that the vehicle sensitivity increases as the vehicle speed decreases. For this reason, the vibration generated in the vehicle 10 increases as the vehicle speed decreases. When the retreat travel is performed, the vehicle speed is lowered. For this reason, when the retreat travel is performed, the vibration generated in the vehicle 10 is increased, which gives the driver anxiety.

  Returning to the description of FIG. 3, in the subsequent step S12, it is determined whether or not the specified time TA has elapsed since it was determined in step S10 that an abnormality has occurred. The prescribed time TA is set to several tens of milliseconds, for example.

  If it is determined in step S12 that the determination has been made that no abnormality has occurred before the lapse of the specified time TA after the determination that abnormality has occurred in step S10, the process proceeds to step S13. In step S13, a gradual change process for gradually decreasing the current torque limit coefficient Kv to 0 is performed. As a result, the output value “(1-Kv) × Trq” of the fail safe unit 30e gradually increases to the target torque Trq set by the EVECU 20. In step S13, the temporary abnormality determination is canceled and the temporary abnormality flag Fa is switched from 1 to 0. In the present embodiment, the processing in this step corresponds to a canceling unit.

  On the other hand, if it is determined in step S12 that the specified time TA has elapsed since it was determined in step S10 that an abnormality has occurred, the process proceeds to step S14. In step S14, it is determined whether or not the threshold time TB has elapsed since it was determined in step S10 that an abnormality has occurred. The threshold time TB is set longer than the specified time TA, and is set to several hundred msec, for example.

  In step S14, the specified time TA has elapsed since it was determined that an abnormality has occurred in step S10, but no abnormality has occurred before the threshold time TB has elapsed since it has been determined that an abnormality has occurred. When it is determined that the determination has been switched, the process proceeds to step S13. On the other hand, if it is determined in step S14 that the threshold time TB has elapsed since it was determined in step S10 that an abnormality has occurred, the process proceeds to step S15, where this abnormality is determined, and this abnormality flag Fb is set from 0 to 1. Switch to. Further, by setting the torque limit coefficient Kv for correcting the target torque Trq to 0, the driving of the motor generator 11 is stopped. In the present embodiment, in step S14, processing for notifying the driver that an abnormality has occurred is also performed. In the present embodiment, the process of setting the torque limit coefficient Kv to 0 corresponds to the drive stop unit.

  Next, the failsafe process will be described using the time charts shown in FIGS. Here, FIGS. 8A and 9A show the transition of the presence / absence of abnormality relating to the driving of the motor generator 11, and FIGS. 8B and 9B show the transition of the value of the temporary abnormality flag Fa. 8 (c) and 9 (c) show the transition of the value of the abnormality flag Fb. FIGS. 8 (d) and 9 (d) show the transition of the value expressed as a percentage of the torque limiting coefficient Kv, FIGS. 8 (e) and 9 (e) show the transition of the vehicle speed Vs, and FIG. ) And FIG. 9F show the transition of the q-axis current Iq. FIGS. 8 (g) and 9 (g) show the transition of the steering force assisted by the electric power steering device 15, and FIGS. 8 (h) and 9 (h) show the braking force applied by the brake device 16 to the wheels. Shows the transition.

  First, it demonstrates using FIG. FIG. 8 shows a fail-safe process in the case of shifting from the state where the vehicle 10 is traveling near 30 km / h to the retreat traveling.

  When the abnormality occurs, the fluctuation of the q-axis current Iq increases as shown in FIG. At time t1, it is determined that an abnormality has occurred. Therefore, at time t2, the value of the temporary abnormality flag Fa is switched from 0 to 1, and the torque limit coefficient Kv is set based on the vehicle speed Vs. Thereby, thereafter, the output torque of motor generator 11 is forcibly reduced with respect to target torque Trq. As a result, the peak of output torque can be reduced and the vibration of the vehicle can be reduced. In FIG. 8, for the sake of convenience, the torque limit coefficient Kv is shown as a constant value that does not depend on the vehicle speed Vs during the period from time t2 to time t3.

  By determining that an abnormality has occurred continuously from time t1 until the threshold time TB has elapsed, the value of the abnormality flag Fb is switched from 0 to 1 at time t3. For this reason, the torque limit coefficient Kv is set to 0, and the target correction torque Ttgt becomes 0. Thereby, the drive of the motor generator 11 is stopped. Here, since the output torque is limited until just before the drive of the motor generator 11 is stopped, the output value “(1−Kv) ×× of the fail safe unit 30e immediately before the torque limit coefficient Kv is set to 0. The difference between “Trq” and 0 can be reduced. As a result, it is possible to reduce a shock that occurs when the drive of the motor generator 11 is stopped.

  Incidentally, in the present embodiment, energization to the electric power steering device 15 and the brake device 16 is continued even after the drive of the motor generator 11 is stopped. For this reason, during the retreat travel after time t3, the steering operation is assisted by the electric power steering device 15 and the braking operation is assisted by the brake device 16. As a result, the driver can safely perform evacuation travel.

  Next, description will be made with reference to FIG. FIG. 9 shows fail-safe processing when the vehicle 10 is traveling at a high speed near 80 km / h.

  It is determined that an abnormality has occurred at time t1. Thereafter, at time t2, the value of the temporary abnormality flag Fa is switched from 0 to 1, and the torque limit coefficient Kv is set based on the vehicle speed Vs. Here, the abnormality that occurred at time t1 is a temporary abnormality. The temporary abnormality includes, for example, an abnormality in which noise is temporarily superimposed on a detection value of any one of the phase current sensor 22, the rotation angle sensor 23, and the temperature sensor 24, and the power supplied to the INVECU 30 is temporarily interrupted. So-called instantaneous interruptions are included.

  For this reason, at time t3 before the threshold time TB elapses from time t1, it is determined that the temporary abnormality has been resolved and no abnormality has occurred. Thereby, the value of the temporary abnormality flag Fa is switched from 1 to 0, and the gradual change process is started. The gradual change process suppresses the occurrence of so-called overrun, which is acceleration of the vehicle not intended by the driver. Thereafter, when the torque limit coefficient Kv becomes 0, the vehicle control shifts to the normal control.

  According to the embodiment described in detail above, the following effects can be obtained.

  When the state in which it is determined that an abnormality relating to the phase current sensor 22, the rotation angle sensor 23, or the temperature sensor 24 has continued during the travel of the vehicle 10 continues for the threshold time TB, the torque limit coefficient Kv is set to 0. As a result, the driving of the motor generator 11 was stopped. For this reason, even when the abnormality occurs while the vehicle 10 is traveling in a harsh environment such as a desert region or a cold region, a power source for retreating the vehicle 10 can be secured.

  Further, the target correction torque Ttgt is forcibly decreased on condition that the target correction torque Ttgt is set to a value larger than 0 over a period in which it is determined that the abnormality has occurred while the vehicle 10 is traveling. I let you. For this reason, it is possible to reduce the vibration of the vehicle 10 under a situation in which the retreat traveling should be performed, and to avoid giving the driver anxiety. Therefore, the vehicle 10 can be appropriately retreated.

  If it is determined that no abnormality has occurred before the threshold time TB has elapsed since the start of the determination that an abnormality relating to the phase current sensor 22, the rotation angle sensor 23, or the temperature sensor 24 has occurred, the target torque Trq The forced drop was lifted. Abnormalities include temporary abnormalities such as instantaneous interruption. For this reason, even if it is once determined that an abnormality has occurred by the fail safe unit 30e, the state may return to a state in which no abnormality has occurred thereafter. For this reason, according to the present embodiment, it is possible to prevent the motor 10 from being stopped due to a temporary abnormality and the vehicle 10 from being stopped. Thereby, driving | running | working of the vehicle 10 can be continued.

  When the determination is made that no abnormality has occurred before the threshold time TB has elapsed since it was determined that an abnormality has occurred, the torque limit coefficient Kv was gradually reduced to zero. For this reason, the output torque immediately before the forced decrease in the output torque of the motor generator 11 is released can be gradually brought closer to the target torque Trq. Thereby, it can avoid that a shock arises by canceling the forced fall of output torque, and generation | occurrence | production of overrun can be suppressed.

  The target torque Trq was forcibly decreased over a period from when it was determined that an abnormality occurred until the threshold time TB elapsed. For this reason, the difference between the output torque immediately before the drive of the motor generator 11 is stopped and 0 can be reduced. Thereby, the shock which arises when the drive of the motor generator 11 is stopped can be reduced. Here, the lower the vehicle speed Vs is, the larger the torque limit coefficient Kv is set, so that the effect of reducing the shock caused by stopping the driving of the motor generator 11 is increased.

  The power transmission path connecting the output shaft 11a of the motor generator 11 and the drive wheels 13 is not provided with a transmission. In a configuration in which a transmission is provided in the power transmission path, the transmission absorbs torque fluctuations of the motor generator 11. This is because there are inertia of members constituting the transmission, slipping between members constituting the transmission, and the like. Therefore, in the vehicle 10 according to the present embodiment, when the abnormality occurs, the fluctuation of the output torque generated by the motor generator 11 is easily transmitted to the drive wheels 13 and the vibration of the vehicle 10 is easily increased. For this reason, in this embodiment, when abnormality occurs, the merit which reduces target torque Trq is large.

  The INVECU 30 was made to perform fail-safe processing. For this reason, the target torque Trq can be rapidly reduced when an abnormality occurs as compared with the configuration in which the EV ECU 20 performs the fail-safe process.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment. In the present embodiment, the method for reducing the output torque of the motor generator 11 when an abnormality occurs is changed. Specifically, the output torque is reduced by reducing the feedback gain in the current feedback control.

  FIG. 10 shows a block diagram of torque control according to the present embodiment. In FIG. 10, the same processes as those shown in FIG. 2 are given the same reference numerals for the sake of convenience.

  As illustrated, the INVECU 30 according to the present embodiment does not include the fail safe unit 30e and the selection unit 30f. Only the output value of the temperature multiplier 30d is input to the command current setting unit 30g.

  The fail safe unit 30n basically performs the fail safe process shown in FIG. Specifically, the fail safe unit 30n performs a feedback gain setting process instead of the torque limit coefficient Kv setting process in step S11 of FIG. In this process, as shown in FIG. 11, as the vehicle speed Vs is lower, the proportional gain Kp and the integral gain Ki are set smaller than the proportional gain Kp and the integral gain Ki during normal control where the feedback gain setting process is not performed. It is processing to do. The fail safe unit 30n performs a feedback gain setting process when it is determined that the vehicle speed Vs is equal to or lower than the third vehicle speed. When it is determined that the vehicle speed Vs is higher than the third vehicle speed, the fail safe unit 30n does not perform the feedback gain setting process, and uses the proportional gain Kp and the integral gain Ki during normal control as the proportional gain Kp and the integral gain Ki. Use.

  Further, the fail safe unit 30n is a process of gradually increasing the reduced proportional gain Kp and integral gain Ki to the proportional gain Kp and integral gain Ki during normal control instead of the gradual change process in step S13 of FIG. I do.

  According to the present embodiment described above, the same effect as that of the first embodiment can be obtained.

(Other embodiments)
Each of the above embodiments may be modified as follows.

  In each of the above embodiments, the setting process of the torque limiting coefficient Kv is performed by the INVECU 30, but not limited to this, the EVECU 20 may perform the setting process. In this case, the information regarding the abnormality related to the driving of the motor generator 11 may be transmitted from the INVECU 30 to the EV ECU 20.

  -In the said 1st Embodiment, you may abbreviate | omit the gradual change process of step S13 of FIG.

  The abnormality relating to the driving of the motor generator 11 may include a voltage detection value abnormality in which the power supply voltage VINV detected by the voltage sensor 21 deviates from the actual power supply voltage.

  Further, the abnormality related to the driving of the motor generator 11 is not limited to the abnormality described above, and may include other abnormality such as abnormality of the components of the motor generator 11.

  The feedback control in the d and q axis command voltage calculation units 30j and 30k in FIG. 2 is not limited to proportional integral control, and may be proportional integral differential control or proportional control, for example. Here, in the second embodiment, when differential control is included in the feedback control, the feedback gain used for forcibly reducing the output torque includes a differential gain.

  -Torque control is not limited to current feedback control, and may be torque feedback control, for example. The torque feedback control is a control in which a voltage phase is calculated as an operation amount for performing feedback control of the estimated torque of the motor generator 11 to the target torque Trq, and the switches Sup to Swn of the inverter 12 are operated based on the calculated voltage phase. is there. The estimated torque may be estimated based on, for example, d and q axis currents Idr and Iqr.

  In each of the above embodiments, a salient pole machine is used as the motor generator, but the present invention is not limited to this, and a non-salient pole machine may be used. In this case, instead of the output torque, a q-axis current having a positive correlation with the output torque may be used as the control amount. The motor generator is not limited to a permanent magnet type synchronous machine, and may be a wound field type synchronous machine, for example. Furthermore, the motor generator is not limited to a synchronous machine.

  -Vehicles to which the present invention is applied are not limited to those shown in the above embodiments. For example, the range extender vehicle may further include a dedicated generator for charging the battery 18 and a dedicated engine for driving the generator. The vehicle to which the present invention is applied may be a fuel cell vehicle.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle, 11 ... Motor generator, 12 ... Inverter, 20 ... EVECU, 30 ... INVECU.

Claims (9)

Applied to a vehicle (10) having only a rotating electrical machine (11) as an in-vehicle main machine,
The output torque of the rotating electrical machine or a parameter having a positive correlation with the output torque is used as a controlled variable, and the inverter (12) electrically connected to the rotating electrical machine is operated to control the controlled variable to the target value. An inverter operation unit,
An abnormality determination unit that determines whether an abnormality relating to driving of the rotating electrical machine has occurred;
On the condition that the rotating electrical machine is driven for traveling of the vehicle over a period in which it is determined that an abnormality has occurred during traveling of the vehicle, the actual state of the rotating electrical machine A torque reduction section for forcibly reducing the output torque;
A drive stop unit that stops driving of the rotating electrical machine when a state in which it is determined that an abnormality has occurred by the abnormality determination unit is continued for a threshold time ; and
The said torque reduction part enlarges the amount of reduction | decrease of the said actual output torque, so that the travel speed of the said vehicle is low, The control apparatus of the inverter characterized by the above-mentioned .   When the determination by the abnormality determination unit is switched from the determination with abnormality to the determination without abnormality before the threshold time elapses after the abnormality determination unit starts determining that an abnormality has occurred, the torque reduction unit The inverter control device according to claim 1, further comprising a release unit that releases a decrease in the actual output torque.   The release unit increases the actual output torque so that the actual output torque reduced by the torque reduction unit gradually increases to the output torque when the control amount is controlled to the target value. The inverter control device according to claim 2, wherein the decrease in the inverter is released. The torque reduction unit, by lowering the target value, the inverter control device according to any one of claims 1 to 3 for decreasing the actual output torque. The inverter operation unit operates the inverter to feedback control the control amount to the target value,
The torque reduction unit, by lowering the absolute value of the feedback gain in the feedback control, the inverter control device according to any one of claims 1 to 3 for decreasing the actual output torque. The vehicle includes a phase current sensor (22) that detects a phase current that flows through the rotating electrical machine, and a rotation angle sensor (23) that detects a rotation angle of the rotating electrical machine,
The inverter operation unit operates the inverter to feedback control the control amount to the target value based on the phase current detected by the phase current sensor and the rotation angle detected by the rotation angle sensor.
The abnormality determination unit generates one of an abnormality in which a phase current detected by the phase current sensor deviates from an actual phase current and an abnormality in which a rotation angle detected by the rotation angle sensor deviates from an actual rotation angle. whether it is judged claim 1 inverter control device according to any one of 5. Applied to a vehicle (10) having only a rotating electrical machine (11) as an in-vehicle main machine,
The vehicle includes a phase current sensor (22) that detects a phase current that flows through the rotating electrical machine, and a rotation angle sensor (23) that detects a rotation angle of the rotating electrical machine,
The control amount is based on the phase current detected by the phase current sensor and the rotation angle detected by the rotation angle sensor, with the output torque of the rotating electrical machine or a parameter having a positive correlation with the output torque as a control amount. Inverter operation section for operating the inverter (12) electrically connected to the rotating electrical machine in order to perform feedback control to the target value,
It is determined whether any one of an abnormality in which the phase current detected by the phase current sensor deviates from the actual phase current and an abnormality in which the rotation angle detected by the rotation angle sensor deviates from the actual rotation angle has occurred. An abnormality determination unit to perform,
On the condition that the rotating electrical machine is driven for traveling of the vehicle over a period in which it is determined that an abnormality has occurred during traveling of the vehicle, the actual state of the rotating electrical machine A torque reduction section for forcibly reducing the output torque;
An inverter control device comprising: a drive stopping unit that stops driving of the rotating electrical machine when a state in which an abnormality has been determined by the abnormality determining unit is continued for a threshold time. The vehicle includes a temperature sensor (24) that detects a temperature of a switch (Sup to Swn) that constitutes the inverter,
When it is determined that the temperature detected by the temperature sensor is equal to or lower than a specified temperature, the target value is output as it is, and when it is determined that the temperature detected by the temperature sensor is higher than the specified temperature, the temperature sensor A temperature correction unit (30c, 30d) for lowering and outputting the target value as the temperature detected by
The inverter operation unit operates the inverter to feedback control the control amount to the target value output from the temperature correction unit,
The abnormality determination unit detects an abnormality in which the phase current detected by the phase current sensor deviates from an actual phase current, an abnormality in which a rotation angle detected by the rotation angle sensor deviates from an actual rotation angle, and a detection by the temperature sensor. The inverter control device according to claim 7, wherein it is determined whether any one of abnormalities in which the measured temperature deviates from an actual temperature of the switch has occurred.   The power transmission path connecting between the output shaft (11a) of the rotating electrical machine and the drive wheels (13) of the vehicle is not provided with a transmission. Inverter control device.

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