JP2010022179A - Vehicle and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress heat generation of a motor and to suppress an increase in moving distance of a vehicle at that time. <P>SOLUTION: When a rotation stop temperature rise condition is satisfied, where a temperature rise of the motor is likely to occur when the motor is nearly stopped, a target electrical angle θe* changing along with a change in a phase ωp in period of 2π of the phase ωp in the range from an initial electrical angle θset to a predetermined electrical angle (θset-π) is set (S340) , the current commands Id* and Iq* of the d-axis and q-axis are set so that the electrical angle θe of a rotor of the motor follows the change in the target electrical angle θe* (S350 to S370), and the motor is controlled based on the set current commands Id* and Iq* of the d-axis and q-axis. Consequently, the extreme temperature rise of the motor or the like can be suppressed and the increase in moving distance of the vehicle in a forward and backward direction can be suppressed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle and a control method thereof.

Conventionally, as this type of vehicle, a vehicle that travels using power from a motor has been proposed (see, for example, Patent Document 1). In this vehicle, when the vehicle is stopped on an uphill road while keeping the accelerator opening constant, that is, the vehicle is in a current concentration state in which current concentrates and flows only in one specific phase of each phase coil of the motor. In some cases, the torque output from the motor is reduced at a predetermined rate, the vehicle is moved backward to temporarily leave the current concentration state, thereby suppressing the heat generation of the motor and its drive circuit.
JP-A-11-215687

  In such a vehicle, it is considered that after the torque output from the motor is decreased and the vehicle is moved backward, the torque output from the motor is increased to stop the vehicle. For this reason, when the accelerator opening is kept constant for a certain period of time, the vehicle repeats stopping and retreating, and the moving distance of the vehicle after the vehicle first starts retreating becomes relatively long. Sometimes.

  The main object of the vehicle and the control method thereof according to the present invention is to suppress the heat generation of the electric motor and to prevent the movement distance of the vehicle at that time from becoming long.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve the main object described above.

The vehicle of the present invention
An electric motor capable of outputting power to a drive shaft connected to the drive wheel;
When the rotation stop temperature increase condition for which the motor temperature is substantially stopped and the temperature increase of the motor is assumed is satisfied, an initial electric angle that is an electric angle of the motor when the rotation stop temperature increase condition is satisfied is set. Control means for performing periodic change control for controlling the electric motor so that the electric angle of the electric motor changes in a predetermined cycle including a predetermined angular range,
It is a summary to provide.

  In the vehicle according to the present invention, when the rotation stop temperature increase condition for which the motor is substantially stopped and the temperature increase of the motor is assumed is satisfied, the initial electric angle of the motor when the rotation stop temperature increase condition is satisfied Periodic change control is performed for controlling the electric motor so that the electric angle of the electric motor changes in a predetermined cycle within a predetermined angular range including the electric angle. That is, when the rotation stop temperature increase condition is satisfied, the electric angle of the motor changes within a predetermined angular range at a predetermined cycle (the vehicle moves at a predetermined cycle within a distance corresponding to the predetermined angular range of the electric angle of the electric motor). The motor is controlled so that Accordingly, it is possible to suppress the heat generation of the electric motor or the like due to the current flowing in a specific phase among the phases of the electric motor, and it is possible to suppress an increase in the moving distance of the vehicle. Here, the “rotation stop temperature increase condition” is a condition that is satisfied when the state in which the electric motor is substantially stopped in rotation and a torque higher than the predetermined torque is output from the electric motor continues for a predetermined time. You can also The “predetermined angle range” is a range having a boundary between the initial electrical angle and a predetermined electrical angle at which the state of the phase current of the motor is different from the state at the initial electrical angle. You can also.

  In such a vehicle of the present invention, the control means sets a target electrical angle that changes the predetermined angle range in the predetermined cycle as the periodic change control, and the electrical angle of the motor is the set target electrical angle. It may be a means for controlling the electric motor so that a torque that follows the change in angle is output from the electric motor. If it carries out like this, the electrical angle of an electric motor can be made to follow the change of the target electrical angle which changes a predetermined angle range in a predetermined range.

  In the vehicle of the present invention in which the electric motor is controlled such that the electric angle of the electric motor follows the change in the target electric angle is output from the electric motor, the control means is based on the required torque required for the drive shaft. When setting the torque command of the motor and executing the periodic change control, a temporary current command that is a temporary value of the d-axis and q-axis current commands is set based on the set torque command, and the setting is performed. A temporary current command angle that is an angle based on a ratio between the d-axis temporary current command and the set q-axis temporary current command and the q axis is set, and the set temporary current command angle is set to the electric current of the motor. A current command angle which is an angle corrected based on the angle and the target electrical angle is set, the d-axis and q-axis current commands are set based on the set current command angle, and the set d-axis , Based on the q-axis current command It may be assumed to be a means for controlling the motive. In this way, the electric angle of the motor is changed to the target electric angle by setting the d-axis and q-axis current commands based on the current command angle set by correcting the temporary current command angle and controlling the motor. Can be followed.

  In the vehicle of the present invention in which the d-axis and q-axis current commands are set based on the current command angle set by correcting the temporary current command angle and the motor is controlled, the control means includes the periodic change control. Is set based on the d-axis and q-axis temporary current commands, and the set temporary current command is set as a temporary current command size that is a temporary value of the current to be supplied to the motor. A current command magnitude that is a magnitude corrected based on the electrical angle of the motor and the target electrical angle is set, and the d command is set based on the set current command magnitude and the set current command angle. It may be a means for setting a current command for the axis and the q-axis. In this way, the electrical angle of the motor can be accurately followed by the change in the target electrical angle.

  In the vehicle of the present invention in which the d-axis and q-axis current commands are set based on the current command angle set by correcting the temporary current command angle and the motor is controlled, the control means includes the periodic While the change control is being executed, the target electrical angle changes in the vehicle downward direction, which is the direction in which the vehicle descends the uphill road, and the target electrical angle is within the predetermined angle range. The d-axis and the q-axis are based on a current command magnitude larger than the set temporary current command magnitude and the set current command angle when within a second predetermined angle range including a boundary on the downstream side. It may be a means for setting the current command. If it carries out like this, it can suppress that the electrical angle of an electric motor exceeds the boundary of the vehicle downward direction side of a predetermined angle range.

  In the vehicle of the present invention in which the electric motor is controlled such that the electric angle of the electric motor follows the change in the target electric angle is output from the electric motor, the control means is executing the periodic change control. When the target electrical angle changes in the vehicle downward direction, which is the direction in which the vehicle goes down the uphill road, the periodic change occurs when the electrical angle of the motor no longer follows the change in the target electrical angle. The control is interrupted, and after the interruption, the target electrical angle changes in the vehicle upward direction, which is the direction in which the vehicle goes up the slope, and the target electrical angle is on the vehicle upward direction side as compared with the electrical angle of the electric motor. It is also possible to use means for resuming the periodic change control when the angle is reached. In this case, the control means is means for controlling the electric motor so that no current flows through the electric motor when the rotation stop temperature increase condition is satisfied and the execution of the periodic change control is interrupted. It can also be. If it carries out like this, it can suppress flowing a useless electric current into an electric motor, and can suppress more heat_generation | fever and temperature rises, such as an electric motor.

  Further, in the vehicle of the present invention in which the electric motor is controlled such that a torque at which the electric angle of the electric motor follows the change in the target electric angle is output from the electric motor, the control means is configured to satisfy the rotation stop temperature increase condition. The sum of the torque based on the torque required for the drive shaft and the torque for canceling the difference between the electric angle of the electric motor and the target electric angle is set in the torque command of the electric motor, and the set torque It may be a means for controlling the electric motor so that the electric motor is driven by a command.

  In the vehicle of the present invention, the control means is means for terminating the periodic change control when the electrical angle of the electric motor is out of the predetermined angle range during execution of the periodic change control. The periodic change control is terminated when the accelerator operation amount is larger than a predetermined amount with respect to the initial accelerator operation amount when the rotation stop temperature increase condition is satisfied. It can also be a means to do.

The vehicle control method of the present invention includes:
A control method for a vehicle including an electric motor capable of outputting power to a drive shaft connected to a drive wheel,
When the rotation stop temperature increase condition for which the motor temperature is substantially stopped and the temperature increase of the motor is assumed is satisfied, an initial electric angle that is an electric angle of the motor when the rotation stop temperature increase condition is satisfied is set. Performing a periodic change control for controlling the electric motor so that the electric angle of the electric motor changes in a predetermined cycle including a predetermined angle range.
It is characterized by that.

  In this vehicle control method of the present invention, when the rotation stop temperature increase condition that the motor is substantially stopped and the temperature increase of the motor is assumed is satisfied, the electric angle of the motor when the rotation stop temperature increase condition is satisfied. Periodic change control is performed for controlling the electric motor so that the electric angle of the electric motor changes within a predetermined angular range including the initial electric angle. That is, when the rotation stop temperature increase condition is satisfied, the electric angle of the motor changes within a predetermined angular range at a predetermined cycle (the vehicle moves at a predetermined cycle within a distance corresponding to the predetermined angular range of the electric angle of the electric motor). The motor is controlled so that Accordingly, it is possible to suppress the heat generation of the electric motor or the like due to the current flowing in a specific phase among the phases of the electric motor, and it is possible to suppress an increase in the moving distance of the vehicle. Here, the “rotation stop temperature increase condition” is a condition that is satisfied when the state in which the electric motor is substantially stopped in rotation and a torque higher than the predetermined torque is output from the electric motor continues for a predetermined time. You can also The “predetermined angle range” is a range having a boundary between the initial electrical angle and a predetermined electrical angle at which the state of the phase current of the motor is different from the state at the initial electrical angle. You can also.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of the configuration of an electric vehicle 20 as a first embodiment of the present invention. As shown in the drawing, the electric vehicle 20 of the first embodiment includes a motor 22 that can input and output power to a drive shaft 32 connected to drive wheels 30a and 30b via a differential gear 31, and an inverter that drives the motor 22. The battery 26 which exchanges electric power with the motor 22 via 24, and the electronic control unit 40 which controls the whole vehicle are provided.

  FIG. 2 is a configuration diagram centering on the electric system of the electric vehicle 20 of the first embodiment. The motor 22 is configured as a well-known synchronous generator motor including a rotor 22a in which permanent magnets are embedded and a stator 22b in which a three-phase coil is wound. The inverter 24 includes six transistors Tr1 to Tr6 and six diodes D1 to D6 connected in parallel to the transistors Tr1 to Tr6 in the reverse direction. Two transistors Tr1 to Tr6 are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode bus and the negative electrode bus to which the battery 26 is connected, and at each connection point between the paired transistors. Each of the three-phase coils (U phase, V phase, W phase) of the motor 22 is connected. Therefore, a rotating magnetic field can be formed in the three-phase coil by controlling the ratio of the on-time of the transistors Tr1 to Tr6 that make a pair while a voltage is acting between the positive electrode bus and the negative electrode bus, and the motor 22 is rotated. Can be driven.

  The electronic control unit 40 is configured as a microprocessor centered on the CPU 42. In addition to the CPU 42, a ROM 44 for storing processing programs, a RAM 46 for temporarily storing data, an input / output port and a communication port (not shown), Is provided. The electronic control unit 40 detects the rotational position θm of the rotor 22a from the rotational position detection sensor 23 that detects the rotational position of the rotor 22a of the motor 22, and the phase currents flowing in the U phase and V phase of the three-phase coil of the motor 22. Shift position sensor for detecting phase currents Iu and Iv from the current sensors 22U and 22V, a battery temperature from a temperature sensor (not shown) for detecting the temperature of the battery 26, an ignition signal from the ignition switch 50, and an operating position of the shift lever 51 52, the shift position SP from 52, the accelerator opening Acc from the accelerator pedal position sensor 54 that detects the amount of depression of the accelerator pedal 53, the brake pedal position BP from the brake pedal position sensor 56 that detects the amount of depression of the brake pedal 55, and the vehicle speed Sensor 58 And La of the vehicle speed V is input via the input port. From the electronic control unit 40, a switching control signal to the switching elements (transistors Tr1 to Tr6) of the inverter 24 for driving and controlling the motor 22 is output via an output port. The electronic control unit 40 also calculates the electrical angle θe of the rotor 22a and the rotational speed Nm of the motor 22 based on a signal from the rotational position detection sensor 23. In the electric vehicle 20 of the embodiment, the shift position SP detected by the shift position sensor 52 includes a parking position (P position), a neutral position (N position), a drive position (D position), and a reverse position (R position). and so on.

  Next, the operation of the electric vehicle 20 of the first embodiment configured as described above, particularly the operation when the vehicle is stopped in a state where the accelerator pedal 53 is depressed on the uphill road will be described. FIG. 3 is a flowchart showing an example of a drive control routine executed by the electronic control unit 40. This routine is repeatedly executed every predetermined time (for example, every several msec).

  When the drive control routine is executed, first, the CPU 42 of the electronic control unit 40 first determines the accelerator opening Acc from the accelerator pedal position sensor 54, the vehicle speed V from the vehicle speed sensor 58, the electrical angle θe of the rotor 22a of the motor 22, the motor. Data required for control such as the rotational speed Nm of 22 and the phase currents Iu and Iv flowing in the U-phase and V-phase of the three-phase coil of the motor 22 from the current sensors 22U and 22V are input (step S100), and the input accelerator Based on the opening degree Acc and the vehicle speed V, the required torque Td * to be output to the drive shaft 32 is set (step S110), and the set required torque Td * is set as the torque command Tm * of the motor 22 (step S120). . Here, the electrical angle θe of the rotor 22 a and the rotational speed Nm of the motor 22 are calculated based on the rotational position θm of the rotor 22 a detected by the rotational position detection sensor 23, and are read at a predetermined address in the RAM 46. To enter. The electrical angle θe of the rotor 22a and the rotational speed Nm of the motor 22 indicate the rotational direction of the rotor 22a when the vehicle travels in the traveling direction corresponding to the shift position SP (the forward direction when the shift position SP is the D position). The direction was positive. In the first embodiment, the required torque Td * is stored in the ROM 44 as a required torque setting map by predetermining the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Td *, and the accelerator opening Acc and the vehicle speed. When V is given, the corresponding required torque Td * is derived from the stored map and set. FIG. 4 shows an example of the required torque setting map.

  Subsequently, the sum of the phase currents Iu, Iv, and Iw flowing in the U-phase, V-phase, and W-phase of the three-phase coil of the motor 22 is 0, and the phase currents Iu and Iv are d-axis and q-axis using the electrical angle θe. Currents Id and Iq are subjected to coordinate transformation (three-phase to two-phase transformation) by the following equation (1) (step S130), and the value of the condition satisfaction flag F is examined (step S140). Here, the value 0 is set as the initial value of the condition satisfaction flag F, and the value 1 is set when the rotation stop temperature increase condition that the temperature of the motor 22 or the like is expected to increase is satisfied. The flag to be set. The d-axis is the direction of the magnetic flux formed by the permanent magnet embedded in the rotor 22a of the motor 22, and the q-axis advances the electrical angle by π / 2 in the direction in which the motor 22 is normally rotated with respect to the d-axis. It is the direction which made it horn.

  When the condition satisfaction flag F is 0, the absolute value of the rotational speed Nm of the motor 22 is compared with a threshold value Nref (step S150), and the torque command of the motor 22 that was set when this routine was executed last time (previous time). (Tm *) is compared with the threshold value Tref (step S160). When the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or greater than the threshold value Tref, this state is It is determined whether or not the operation has continued for a predetermined time (step S170). The processing in steps S150 to S170 is processing for determining whether or not the above-described rotation stop temperature increase condition is satisfied. Here, the threshold value Nref is used to determine whether or not the motor 22 has stopped substantially rotating (whether or not the vehicle is stopped). For example, 50 rpm or 100 rpm can be used. . The threshold value Tref is used to determine whether or not a certain amount of torque is output from the motor 22 and is determined by the characteristics of the motor 22 and the like. Furthermore, the predetermined time is determined, for example, as a time during which heat generation of the motor 22 and the inverter 24 can be allowed, and can be set according to the specifications of the motor 22 and the inverter 24. First, when the vehicle is stopped when the accelerator pedal 53 is depressed and held on the uphill road (when the motor 22 is stopped rotating), the motor 22 is stopped rotating. When a relatively large torque is output from the motor 22, a large current flows only in a specific phase among the three-phase coils of the motor 22. Therefore, the temperature increase of the motor 22 and the inverter 24 is easily promoted, and May rise excessively. Next, considering that the accelerator pedal 53 is depressed relatively large when the vehicle starts on a flat ground, the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref even at this time. Although the torque command (previous Tm *) may be equal to or greater than the threshold value Tref, in this case, since this state is relatively short, it is considered that the temperature of the motor 22 and the inverter 24 does not increase so much. The processing of steps S150 to S170 is whether the vehicle is stopped with the accelerator pedal 53 being depressed and held on the uphill road, and the temperature of the motor 22 and the inverter 24 may increase excessively. It is a process which determines.

  When the absolute value of the rotational speed Nm of the motor 22 is greater than the threshold value Nref, or when the previous torque command (previous Tm *) of the motor 22 is less than the threshold value Tref, the absolute value of the rotational speed Nm of the motor 22 is less than or equal to the threshold value Nref. When the previous torque command (previous Tm *) of the motor 22 is not yet over the predetermined time Tref, a value 0 is set to the condition satisfaction flag F (step S180), and the motor 22 Based on the torque command Tm *, d-axis and q-axis current commands Id * and Iq * are set (step S200). Here, in the first embodiment, the d-axis and q-axis current commands Id * and Iq * are the relationship between the torque command Tm * and the d-axis and q-axis current commands Id * and Iq * (for example, the current command The square root of the sum of the square of Id * and the square of the current command Iq * (hereinafter referred to as the current command magnitude Ire) is relatively small so that the torque corresponding to the torque command Tm * can be output from the motor 22 in advance. It is determined and stored in the ROM 44 as a current command setting map, and when the torque command Tm * is given, the corresponding d-axis and q-axis current commands Id * and Iq * are derived and set from the stored map. did. An example of the current command setting map is shown in FIG. In the example of FIG. 5, when the torque command Tm * is the torque T3, the d-axis and q-axis current commands Id * and Iq * corresponding to the torque command Tm * are set. In addition to the torque command Tm * and the current commands Id * and Iq *, FIG. 5 shows the current command magnitude Ire and the direction of the magnetic field formed in the stator 22b by the current supplied to the three-phase coil (stator The current command angle θre as an angle of the magnetic field direction) with respect to the q axis is also illustrated. In the first embodiment, since the motor 22 in which the permanent magnet is embedded in the rotor 22a is used, in consideration of the generation of the reluctance torque in addition to the torque by the permanent magnet, the current command angle is shown as shown in the figure. θre has a value of 0 to π. However, when the motor 22 having a permanent magnet attached to the outer surface of the rotor 22a is used, reluctance torque is not generated, so that the current command angle θre has a value of 0 or π / 2. Become.

  Subsequently, using the d-axis and q-axis current commands Id * and Iq * and the currents Id and Iq, the d-axis and q-axis voltage commands Vd * and Vq * are obtained by the following equations (2) and (3). The voltage command Vu * to be applied to the U-phase, V-phase, and W-phase of the three-phase coil of the motor 22 using the electrical angle θe and calculating the d-axis and q-axis voltage commands Vd * and Vq * using the electrical angle θe. , Vv *, and Vw * are subjected to coordinate transformation (two-phase to three-phase transformation) according to equations (4) and (5) (step S280), and the coordinate-converted voltage commands Vu *, Vv *, and Vw * are The motor 22 is driven and controlled by converting it into a PWM signal for switching the transistors Tr1 to Tr6 and outputting it to the transistors Tr1 to Tr6 of the inverter 24 (step S290), and the drive control routine is terminated. Here, in Expression (2) and Expression (3), “Kp1” and “Kp2” are proportional coefficients, and “Ki1” and “Ki2” are integration coefficients. In this case, the motor 22 is controlled using the d-axis and q-axis current commands Id * and Iq * corresponding to the electrical angle θe of the rotor 22a and the torque command Tm *.

  When the absolute value of the rotation speed Nm of the motor 22 is equal to or smaller than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or greater than the threshold value Tref in steps S150 to S170, that is, rotation When the stop temperature increase condition is satisfied, a value 1 is set to the condition satisfaction flag F (step S210), and the current electrical angle θe of the rotor 22a is set to the initial electrical angle θset, which is the electrical angle at this time. The current accelerator opening Acc is set to the initial opening Aset which is the accelerator opening (step S220), and the time t after the condition is satisfied, which is the time from this time, is reset and time counting is started (step S230).

  Then, the difference between the accelerator opening Acc and the initial opening Aset is set to the opening difference ΔAcc (step S240), and the set opening difference ΔAcc is compared with the threshold value Aref (step S250). Here, the threshold value Aref is used to determine whether or not the driving request for driving by the driver has changed, and is determined by the specification of the vehicle. When the opening degree difference ΔAcc is smaller than the threshold value Aerf, it is determined that the driving request for driving by the driver has not changed, and the d-axis and q-axis current commands Id * and Iq are determined by the current command setting process illustrated in FIG. * Is set (step S260), the processing of steps S270 to S290 is executed, and the drive control routine is terminated. The current command setting process in FIG. 6 will be described later.

  On the other hand, when the opening degree difference ΔAcc is greater than or equal to the threshold value Aref in step S250, it is determined that the driving request for driving by the driver has changed, and the value 0 is set in the condition satisfaction flag F (step S180). Execute the process. When this current command setting process is executed after the next time, the condition satisfaction flag F is 0 in step S140, and the processes after step S150 are executed.

  Next, the current command setting process of FIG. 6 will be described. In the current command setting process, first, the d-axis and q-axis temporary current commands Idtmp and Iqtmp are set based on the torque command Tm * of the motor 22 (step S300). Here, the d-axis and q-axis temporary current commands Idtmp and Iqtmp are obtained by replacing “Id *” and “Iq *” in the current command setting map in FIG. 5 with “Idtmp” and “Iqtmp”. The setting is made based on the torque command Tm *.

  Thus, when the d-axis and q-axis temporary current commands Idtmp and Iqtmp are set, the temporary current command magnitude that is a temporary value of the current command magnitude Ire based on the set d-axis and q-axis temporary current commands Idtmp and Iqtmp. Iretmp is calculated by the following equation (6) (step S310), and a temporary current command angle θre, which is a temporary value of the current command angle θre, is calculated based on the d-axis and q-axis temporary current commands Idtmp and Iqtmp (7). ) (Step S320).

  Subsequently, the phase ωp is calculated by converting the value (ω · t) obtained by multiplying the time t after the condition is satisfied by the angular frequency ω to be within the range of the value 0 to 2π (step S330), and the calculated phase ωp is calculated. Using the following equation (8), the target electrical angle θe * of the rotor 22a is set (step S340). Here, the phase ωp is such that the electrical angle θe of the rotor 22a is in a predetermined angular range (a range of an initial electrical angle θset to be described later to a predetermined electrical angle (θset−π)) with a predetermined period C (for example, 0.5 seconds or This is used to set the target electrical angle θe * used when executing the periodic change control for controlling the motor 22 so as to change in 1 second, 2 seconds, etc. Further, the angular frequency ω is used so that the target electrical angle θe * changes in a predetermined angular range with a predetermined period C, and is represented by (2π / C). The target electrical angle θe * calculated in this way ranges from an initial electrical angle θset to a predetermined electrical angle (θset−π) with a change in the phase ωp, and a period of 2π of the phase ωp (for example, 0.5 seconds or 1 second). , 2 seconds). An example of the relationship between the phase ωp and the target electrical angle θe * is shown in FIG. Note that the predetermined electrical angle (θset−π) is smaller than the initial electrical angle θset, considering that the rotor 22a is negatively rotated (when the accelerator opening Acc is maintained on the uphill road, the vehicle goes down the slope. Side) electrical angle.

  Then, the current command angle θre is calculated by the following equation (9) using the temporary current command angle θretmp, the electrical angle θe of the rotor 22a, and the target electrical angle θe * (step S350), and the temporary current command magnitude Iretmp and the rotor are calculated. The current command magnitude Ire is calculated by Formula (10) using the electrical angle θe and the target electrical angle θe * of 22a (Step S360), and Formula (11) is calculated using the current command magnitude Ire and the current command angle θre. ) And (12), the d-axis and q-axis current commands Id * and Iq * are calculated (step S370), and the current command setting process is terminated. Here, Expressions (9) and (10) are expressions for causing the electrical angle θe of the rotor 22a to follow the change in the target electrical angle θe *, and in Expression (10), “Kp3” is a gain of a proportional term. It is. Equations (11) and (12) are equations for converting the current command magnitude Ire into d-axis and q-axis current commands Id * and Iq * using the current command angle θre. FIG. 8 shows an example of the relationship between the d-axis and q-axis temporary current commands Idtmp and Iqtmp and the d-axis and q-axis current commands Id * and Iq *. By controlling the motor 22 using the d-axis and q-axis current commands Id * and Iq * set in this way, the torque output from the motor 22 changes and the rotor 22a and the drive wheel 30a connected to the rotor 22a are changed. , 30b rotate and the vehicle moves in the front-rear direction, so that the electrical angle θe of the rotor 22a of the motor 22 can follow the change in the target electrical angle θe *. The control for controlling the motor 22 in this way corresponds to the above-described periodic change control. If the electrical angle θe is changed by the rotation of the rotor 22a in this way, it is possible to suppress a large current from flowing only in a specific phase of the three-phase coil of the motor 22, and an excessive temperature of the motor 22 or the inverter 24 is suppressed. The rise can be suppressed. In addition, as illustrated in FIG. 7, in the first embodiment, the target electrical angle θe * has a range from the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp (for example, 0. The electrical angle θe of the rotor 22a changes in a range from the initial electrical angle θset to a predetermined electrical angle (θset−π) with a predetermined period C, that is, 5 seconds, 1 second, 2 seconds, etc. The vehicle moves in the front-rear direction at a predetermined period C in a range from a position corresponding to the initial electrical angle θset to a position corresponding to a predetermined electrical angle (θset−π) (for example, about several centimeters). Even when the degree Acc is held for a certain period of time, it is possible to suppress an increase in the moving distance of the vehicle in the front-rear direction.

  According to the electric vehicle 20 of the first embodiment described above, the state in which the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or greater than the threshold value Tref is a predetermined time. When the rotation stop temperature increase condition that continues over the period is satisfied, the target electrical angle that changes in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp as the phase ωp changes. Since the motor 22 is controlled by setting the d-axis and q-axis current commands Id * and Iq * so that the electrical angle θe of the rotor 22a follows the change in θe *, an excessive temperature rise of the motor 22 and the inverter 24 is caused. It can suppress and it can suppress that the moving distance of the vehicle front-back direction in that case becomes long.

  In the electric vehicle 20 of the first embodiment, when the rotation stop temperature increase condition is satisfied, the current is calculated by the above equation (9) using the temporary current command angle θretmp, the electrical angle θe of the rotor 22a, and the target electrical angle θe *. The command angle θre is calculated, the current command magnitude Ire is calculated by the equation (10) using the temporary current command magnitude Iretmp, the electrical angle θe of the rotor 22a, and the target electrical angle θe *, and the current command magnitude Ire The d-axis and q-axis current commands Id * and Iq * are calculated by using the current command angle θre and the equations (11) and (12), but the temporary current command angle θretmp and the electrical angle θe of the rotor 22a are calculated. And the target electrical angle θe * are used to calculate the current command angle θre according to equation (9), and the temporary current command magnitude Iretmp and the current command angle θre are used to calculate “Ire” in equations (11) and (12). The d-axis by replaced with a "Iretmp", the current command Id * of the q-axis, may be adapted to calculate the Iq *. FIG. 9 shows an example of the relationship between the d-axis and q-axis temporary current commands Idtmp and Iqtmp and the d-axis and q-axis current commands Id * and Iq * in this case. Even in this case, the electrical angle θe of the rotor 22a can follow the change of the target electrical angle θe * to some extent.

  Next, an electric vehicle 20B as a second embodiment of the present invention will be described. The electric vehicle 20B of the second embodiment has the same hardware configuration as the electric vehicle 20 of the first embodiment described with reference to FIG. Therefore, in order to avoid redundant description, detailed description of the hardware configuration of the electric vehicle 20B of the second embodiment is omitted.

  In the electric vehicle 20B of the second embodiment, the electronic control unit 40 executes the current command setting process of FIG. 10 instead of the current command setting process of FIG. The current command setting process in FIG. 10 is the same as the current command setting process in FIG. 6 except that the processes in steps S400 to S420 are executed instead of the process in step S360. Therefore, the same step number is assigned to the same process as the current command setting process of FIG. 6, and the detailed description is omitted.

  In the current command setting process of FIG. 10, when the current command angle θre is calculated in step S350, it is determined whether or not the phase ωp is not less than π / 2 and not more than π (step S400). Considering when the accelerator opening degree Acc is maintained on the uphill road, when the phase ωp is in the range of 0 to π, the target electrical angle is set in the direction in which the rotor 22a rotates negatively (the vehicle goes down the slope). θe * changes. Therefore, when the target electrical angle θe * changes from the initial electrical angle θset toward the predetermined electrical angle (θset−π) and is close to the predetermined electrical angle (θset−π), the target electrical angle θe * changes. By executing the periodic change control for controlling the motor 22 so that the electrical angle θe of the rotor 22a follows, the electrical angle θe is changed to a predetermined electrical angle (θset−π) by the component force in the vehicle longitudinal direction (vehicle weight component force). ) May become smaller. The determination of whether or not the phase ωp in step S400 is greater than or equal to π / 2 and less than or equal to π is a process for determining the presence or absence of this possibility. When the phase ωp is not less than π / 2 and not less than π, it is determined that this possibility is low, the temporary current command magnitude Iretmp is set to the current command magnitude Ire (step S410), and the current command magnitude Ire and the current command are set. Using the angle θre, the d-axis and q-axis current commands Id * and Iq * are calculated by the equations (11) and (12) (step S370), and the current command setting process is terminated. On the other hand, when the phase ωp is greater than or equal to π / 2 and less than or equal to π, it is determined that the electrical angle θe may become smaller than a predetermined electrical angle (θset−π). The current command magnitude Ire is calculated by multiplying the temporary current command magnitude Iretmp (for example, the value 1.1 or 1.2) (step S420), and the current command magnitude Ire and the current command angle θre are used. Then, d-axis and q-axis current commands Id * and Iq * are calculated according to equations (11) and (12) (step S370), and the current command setting process is terminated. As described above, when the phase ωp is not less than π / 2 and not more than π, the d-axis and q-axis current commands Id * and Iq * are set based on the current command magnitude Ire larger than the temporary current command magnitude Iretmp. By controlling the motor 22, the output from the motor 22 is output as compared with the control of the motor 22 by setting the d-axis and q-axis current commands Id * and Iq * based on the temporary current command absolute value Iretmp. Since the torque (torque in the direction in which the vehicle goes up the hill) increases, the rotor 22a rotates negatively (the vehicle moves in the direction in the down hill). The increase in value can be suppressed, and the electrical angle θe of the rotor 22a can be suppressed from exceeding a predetermined electrical angle (θset−π).

  According to the electric vehicle 20B of the second embodiment described above, when the periodic change control is executed, if the phase ωp is π / 2 or more and π or less, the provisional current command magnitude based on the torque command Tm * is obtained. Since the motor 22 is controlled by setting the d-axis and q-axis current commands Id * and Iq * based on the current command magnitude Ire larger than Iretmp, the electrical angle θe of the rotor 22a is set to a predetermined electrical angle (θset−π). ) Can be suppressed from becoming smaller.

  In the electric vehicle 20B of the second embodiment, when the phase ωp is not less than π / 2 and not more than π, the provisional current command magnitude Iretmp is multiplied by the correction coefficient Kad (for example, the value 1.1 or the value 1.2). The current command magnitude Ire is calculated as long as the current command magnitude Ire larger than the temporary current command magnitude Iretmp is set. For example, a positive predetermined value ΔIre is set to the temporary current command magnitude Iretmp. The current command magnitude Ire may be calculated in addition to Iretmp.

  In the electric vehicle 20B of the second embodiment, when the phase ωp is not less than π / 2 and not more than π, the d-axis and q-axis current commands Id are based on the current command magnitude Ire larger than the temporary current command magnitude Iretmp. *, Iq * are set, but the provisional current command magnitude Iretmp is within the range of the phase ωp that can prevent the electrical angle θe of the rotor 22a from exceeding a predetermined electrical angle (θset−π). It is only necessary to set the d-axis and q-axis current commands Id * and Iq * based on a larger current command magnitude Ire. For example, when the phase ωp is 2π / 3 or more and π or less, or the phase ωp When d is greater than 0 and less than or equal to π, the d-axis and q-axis current commands Id * and Iq * may be set based on a current command magnitude Ire larger than the temporary current command magnitude Iretmp.

  Next, an electric vehicle 20C as a third embodiment of the present invention will be described. The electric vehicle 20C according to the third embodiment has the same hardware configuration as the electric vehicle 20 according to the first embodiment described with reference to FIG. Therefore, in order to avoid redundant description, detailed description of the hardware configuration of the electric vehicle 20C of the third embodiment is omitted.

  In the electric vehicle 20C of the third embodiment, the electronic control unit 40 executes the current command setting process of FIG. 11 instead of the current command setting process of FIG. The current command setting process in FIG. 11 is the same as the current command setting process in FIG. 6 except that the processes in steps S500 to S550 are added. Therefore, the same step number is assigned to the same process as the current command setting process of FIG. 6, and the detailed description is omitted.

  In the current command setting process of FIG. 11, when the target electrical angle θe * is set in step S350, it is determined whether or not the phase ωp is greater than 0 and less than or equal to π (step S500), and the phase ωp is greater than 0. When it is less than or equal to π, the difference Δθe between the target electrical angle θe * and the electrical angle θe of the rotor 22a is calculated (step S510), and the calculated difference Δθe is compared with the threshold value θref (step S520). Here, the determination in step S500 is a process of determining whether or not the target electrical angle θe * is changing in the direction in which the rotor 22a rotates negatively (the direction in which the vehicle goes down the slope). The threshold value θref in step S520 is used to determine whether or not the electrical angle θe of the rotor 22a follows the change in the target electrical angle θe *, and is determined by the vehicle specifications and the like. When there is an obstacle such as a vehicle stop in the direction in which the vehicle goes down the slope, the electrical angle θe of the rotor 22a changes to the target electrical angle θe * while the rotor 22a is rotating negatively (the vehicle is going down the slope). May not follow. The determination in steps S500 and S520 is that the electrical angle θe follows the change in the target electrical angle θe * when the target electrical angle θe * is changing in the direction in which the rotor 22a rotates negatively (the vehicle goes down the slope). It is a process of determining whether or not.

  When the difference Δθe is less than or equal to the threshold θref, it is determined that the electrical angle θe of the rotor 22a follows the change in the target electrical angle θe *, and the current command angle θre and the current command magnitude Ire are calculated (step S350). , S360), d-axis and q-axis current commands Id * and Iq * are calculated (step S370), and the current command setting process is terminated. In this case, periodic change control is executed.

  On the other hand, when the difference Δθe is larger than the threshold value θref in step S520, it is determined that the electrical angle θe does not follow the change in the target electrical angle θe *, and both the values of the d-axis and q-axis current commands Id * and Iq * are values. 0 is set (step S530), and the current command setting process is terminated. In this case, no current is passed through each phase of the motor 22, that is, the periodic change control is interrupted. Accordingly, it is possible to suppress the periodic change control from being performed even if the vehicle does not move in the direction of going down the slope due to an obstacle such as a vehicle stop, and it is possible to suppress a wasteful current from flowing to the motor 22. As a result, the heat generation and temperature rise of the motor 22 and the inverter 24 can be further suppressed.

  When the phase ωp is greater than 0 and not less than π in step S500, that is, when the phase ωp is greater than π and less than 2π (value 0), the previous d-axis and q-axis current commands (previous Id *), (previous It is determined whether or not (Iq *) is 0 (step S540). This determination is a process for determining whether or not the periodic change control is interrupted. When the previous d-axis and q-axis current commands (previous Id *) and (previous Iq *) are not 0, it is determined that the periodic change control has not been interrupted, and the processing of steps S350 to S370 is executed. The current command setting process is terminated.

  On the other hand, when the previous d-axis and q-axis current commands (previous Id *) and (previous Iq *) are 0, the target electrical angle θe * is compared with the electrical angle θe (step S550). This comparison is a process for determining whether or not to resume the periodically changed control. When the target electrical angle θe * is equal to or smaller than the electrical angle θe, it is determined that the periodic change control is not resumed, and both the d-axis and q-axis current commands Id * and Iq * are set to 0 (step S530). When the current command setting process is terminated and the target electrical angle θe * is larger than the electrical angle θe, it is determined that the periodic change control is resumed, the processes of steps S350 to S370 are executed, and the current command setting process is terminated.

  FIG. 12 shows the target electrical angle θe *, the electrical angle θe, and whether or not periodic change control is executed when there is an obstacle such as a vehicle stop in the direction in which the rotor 22a rotates negatively (the vehicle goes down the slope). It is explanatory drawing which shows an example of the mode of a change. As shown in the figure, after time t0 when the rotation stop temperature increase condition is satisfied, the electrical angle θe of the rotor 22a follows the change of the target electrical angle θe * by executing the periodic change control, and the time is stopped by an obstacle such as a car stop. When the electrical angle θe stops following the change of the target electrical angle θe * at t1, the execution of the periodic change control is interrupted. When the execution of the periodic change control is resumed at time t2 when the target electrical angle θe * becomes larger than the electrical angle θe, the electrical angle θe of the rotor 22a follows the change in the target electrical angle θe * again. By controlling the motor 22 in this way, it is possible to prevent a wasteful current from flowing through the motor 22 even though the vehicle does not move down the slope, and the motor 22 and the inverter 24 generate heat and increase in temperature. Can be further suppressed.

  According to the electric vehicle 20C of the third embodiment, when the electrical angle θe does not follow the change of the target electrical angle θe * during the periodical change control, the current command for the d-axis and the q-axis is given. Since the motor 22 is controlled by setting both Id * and Iq * to 0, it is possible to prevent unnecessary current from flowing to the motor 22 even if the vehicle does not move down the slope due to an obstacle such as a car stop. In addition, the heat generation and temperature rise of the motor 22 and the inverter 24 can be further suppressed.

  In the electric vehicle 20C of the third embodiment, when the electrical angle θe does not follow the change of the target electrical angle θe * during the execution of the periodic change control, the current command Id * for the d-axis and the q-axis , Iq * are set to a value of 0 to control the motor 22, but the motor 22 may be controlled in the same manner as when the rotation stop temperature increase condition is not satisfied. In this case, in place of the process of step S530 of the current command setting process of FIG. 11, the d-axis and q-axis temporary current commands Idtmp and Iqtmp are set as the d-axis and q-axis current commands Id * and Iq * as they are. Should be executed. Even in this case, it is possible to suppress the execution of the periodic change control even though the vehicle does not move in the direction of going down the slope due to an obstacle such as a vehicle stop. When the periodic change control is executed, the d-axis and q-axis current commands Id * and Iq * are set based on a current command angle θre different from the temporary current command angle θretmp corresponding to the torque command Tm *, and the motor 22 Therefore, a torque different from the torque corresponding to the torque command Tm * is output from the motor 22. In this modified example, when the vehicle does not move down the slope due to an obstacle such as a vehicle stop, the periodic change control is interrupted and the motor 22 is controlled so that the torque corresponding to the torque command Tm * is output from the motor 22. By doing so, when the accelerator pedal 53 is largely depressed at this time and the opening degree difference ΔAcc becomes equal to or greater than the threshold value Aref, it is possible to start traveling more smoothly.

  In the electric vehicle 20C of the third embodiment, when the periodic control is executed, the current command angle θre is calculated by the above equation (9), the current command size Ire is calculated by the equation (10), and the current command size is calculated. The current commands Id * and Iq * for the d-axis and the q-axis are calculated by the equations (11) and (12) using the current Ire and the current command angle θre, but the current command angle θre is calculated by the equation (9). Using the temporary current command magnitude Iretmp and the current command angle θre, the d-axis and q-axis current commands Id are obtained by replacing “Ire” in the equations (11) and (12) with “Iretmp”. *, Iq * may be calculated. Even in this case, the electrical angle θe of the rotor 22a can follow the change of the target electrical angle θe * to some extent.

  Next, an electric vehicle 20D as a fourth embodiment of the present invention will be described. The electric vehicle 20D according to the fourth embodiment has the same hardware configuration as the electric vehicle 20 according to the first embodiment described with reference to FIG. Therefore, in order to avoid redundant description, detailed description of the hardware configuration of the electric vehicle 20D of the fourth embodiment is omitted.

  In the electric vehicle 20D of the fourth embodiment, the electronic control unit 40 executes the drive control routine of FIG. 13 instead of the drive control routine of FIG. In the drive control routine of FIG. 13, first, the CPU 42 of the electronic control unit 40 first performs the accelerator opening Acc, the vehicle speed V, the electrical angle θe of the rotor 22 a, the motor 22, as in the process of step S <b> 100 of the drive control routine of FIG. 4 is input based on the accelerator opening degree Acc and the vehicle speed V, which are necessary for control, such as the rotational speed Nm, the phase currents Iu and Iv flowing in the U-phase and V-phase of the three-phase coil of the motor 22. A required torque Td * to be output to the drive shaft 32 is set using the required torque setting map (steps S600 and S610).

  Subsequently, the value of the condition satisfaction flag F is checked (step S620). When the condition satisfaction flag F is 0, the rotation speed Nm of the motor 22 is determined in the same manner as the processing of steps S150 to S170 of the drive control routine of FIG. The absolute value is compared with the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is compared with the threshold value Tref. When the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref, the previous torque command ( When the previous time Tm *) is equal to or greater than the threshold value Tref, it is determined whether or not this state has continued for a predetermined time (steps S630 to S650).

  When the absolute value of the rotational speed Nm of the motor 22 is greater than the threshold value Nref, or when the previous torque command (previous Tm *) of the motor 22 is less than the threshold value Tref, the absolute value of the rotational speed Nm of the motor 22 is less than or equal to the threshold value Nref. When the previous torque command (previous Tm *) of the motor 22 is not yet over the predetermined time Tref, the condition satisfaction flag F is set to 0 (step S660) and the set request is set. The torque Td * is set to the torque command Tm * for the motor 22 (step S680).

  Then, similarly to the processes of steps S130, S200, S270 to S290 of the drive control routine of FIG. 3, the processes of steps S770 to 810 are executed and the drive control routine is terminated. That is, the sum of the phase currents Iu, Iv, Iw flowing in the U-phase, V-phase, and W-phase of the three-phase coil of the motor 22 is 0, and the phase currents Iu, Iv are d-axis and q-axis using the electrical angle θe. The currents Id and Iq are coordinate-transformed (three-phase to two-phase transformation) according to the above-described equation (1) (step S770), and d based on the torque command Tm * of the motor 22 using the current command setting map of FIG. The axis and q-axis current commands Id * and Iq * are set (step S780), and using the d-axis and q-axis current commands Id * and Iq * and the currents Id and Iq, the equations (2) and (3 ) To calculate the d-axis and q-axis voltage commands Vd * and Vq * (step S790), and use the electrical angle θe to convert the d-axis and q-axis voltage commands Vd * and Vq * to the three-phase coil of the motor 22. The voltage commands Vu *, Vv *, and Vw * to be applied to the U phase, V phase, and W phase are expressed by equation (4) And coordinate conversion (two-phase to three-phase conversion) according to equation (5) (step S800), and the voltage signals Vu *, Vv *, and Vw * subjected to the coordinate conversion are used to switch the transistors Tr1 to Tr6 of the inverter 24. And the motor 22 is driven and controlled by outputting it to the transistors Tr1 to Tr6 of the inverter 24 (step S810), and the drive control routine is terminated.

  Rotation stop temperature rise condition in which the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or greater than the threshold value Tref in steps S630 to S650. Is satisfied, the condition satisfaction flag F is set to 1 (step S690), and the current electrical angle θe of the current rotor 22a and the current accelerator opening Acc are set to the initial electrical angle θset and the initial opening Aset, respectively ( (Step S700), the time t is reset after the condition is established, and time measurement is started (Step S710), and the difference between the accelerator opening Acc and the initial opening Aset is set to the opening difference ΔAcc (Step S720). The opening degree difference ΔAcc is compared with the threshold value Aref (step S730).

  When the opening degree difference ΔAcc is smaller than the threshold value Aerf, the phase ωp is set and the target electrical angle θe * is calculated based on the set phase ωp as in the processing of steps S330 and S340 of the current command setting processing of FIG. (Steps S740 and S750), using the required torque Td *, the electrical angle θe of the rotor 22a, and the target electrical angle θe *, the torque command Tm * is calculated by the following equation (13) (Step S760), and Steps S770 to S810 are performed. This process is executed and the drive control routine is terminated. Here, Expression (13) is a relational expression of feedback for canceling the difference between the electrical angle θe of the rotor 22a and the target electrical angle θe *. In Expression (13), “Kp4” is a proportional term gain. is there. By controlling the motor 22 in this way, the same effects as those of the electric vehicle 20 of the first embodiment can be obtained. That is, the electrical angle θe of the rotor 22a of the motor 22 can be made to follow the change in the target electrical angle θe *, and a large current can be suppressed from flowing only in a specific phase of the three-phase coil of the motor 22, Excessive temperature rise of the motor 22 and the inverter 24 can be suppressed, and even when the accelerator opening degree Acc is held for a certain period of time, it is possible to suppress an increase in the moving distance in the longitudinal direction of the vehicle. it can.

  When the opening degree difference ΔAcc is greater than or equal to the threshold value Aref in step S730, it is determined that the driving request for driving by the driver has changed, a value 0 is set in the condition satisfaction flag F (step S660), and the processing after step S660 is performed. Execute. Then, when this current command setting process is executed after the next time, the condition satisfaction flag F is 0 in step S620, and the processes after step S630 are executed.

  According to the electric vehicle 20D of the fourth embodiment described above, when the rotation stop temperature increase condition is satisfied, the range of the initial electric angle θset to the predetermined electric angle (θset−π) is changed to the phase ωp as the phase ωp changes. Since the motor 22 is controlled by setting the torque command Tm * of the motor 22 so that the electrical angle θe of the rotor 22a follows the change in the target electrical angle θe * that changes at a cycle of 2π, the motor 22 and the inverter 24 are The temperature increase of the vehicle can be suppressed, and the movement distance of the vehicle in the front-rear direction at that time can be suppressed from becoming longer.

  In the electric vehicles 20 to 20D of the first to fourth embodiments, the electrical angle θe of the rotor 22a is between the initial electrical angle θset and the predetermined electrical angle (θset−π) while the periodic change control is being performed. Although no consideration is given to the case of out of the range, the execution of the periodic change control may be terminated at this time. In this case, for example, in the drive control routine of FIG. 3, when the opening difference ΔAcc is less than the threshold value Aref in step S250, the electrical angle θe of the rotor 22a is equal to or less than the initial electrical angle θset and a predetermined electrical angle (θset−π). If the electrical angle θe of the rotor 22a is equal to or smaller than the initial electrical angle θset and equal to or larger than a predetermined electrical angle (θset−π), the processing after step S260 is executed, and the electrical angle of the rotor 22a is determined. When θe is larger than the initial electrical angle θset, or when the electrical angle θe of the rotor 22a is smaller than a predetermined electrical angle (θset−π), the processing after step S180 may be executed. When the periodic change control is executed, the d-axis and q-axis current commands Id * and Iq * are set based on a current command angle θre different from the temporary current command angle θretmp corresponding to the torque command Tm *, and the motor 22 Therefore, a torque different from the torque corresponding to the torque command Tm * is output from the motor 22. For this reason, when the electrical angle θe of the rotor 22a is out of the range of the initial electrical angle θset to the predetermined electrical angle (θset−π), the periodic change control is terminated in order to prevent the driver from feeling uncomfortable. Thus, it is desirable that the torque corresponding to the torque command Tm * is output from the motor 22. In consideration of this, in this modified example, when the electrical angle θe of the rotor 22a is out of the range of the initial electrical angle θset to the predetermined electrical angle (θset−π), the periodic change control is terminated.

  In the electric vehicles 20 to 20D of the first to fourth embodiments, the periodic change control is terminated when the opening difference ΔAcc, which is the difference between the accelerator opening Acc and the initial opening Aset, is equal to or greater than the threshold value Aref. However, instead of or in addition to this, ΔTd, which is the difference between the required torque Td * and the initial required torque Tset, which is the required torque Td * when starting execution of the periodic change control, is equal to or greater than the threshold value Tdref. The periodic change control may be terminated when it becomes. Here, the threshold value Tdref is used for determining whether or not the driving request for driving by the driver has changed, and is determined by the specification of the vehicle.

  In the electric vehicles 20 to 20D of the first to fourth embodiments, when the rotation stop temperature increase condition is satisfied, the electrical angle θe of the rotor 22a is in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π). The motor 22 is controlled so as to change in a sine wave shape with a period of 2π of the phase ωp. However, the motor 22 is not limited to be controlled so as to change in a sine wave shape. For example, the electrical angle θe of the rotor 22a The motor 22 may be controlled so that the range from the angle θset to the predetermined electrical angle (θset−π) is changed by a predetermined amount in a cycle of 2π of the phase ωp.

  In the electric vehicles 20 to 20D of the first to fourth embodiments, the range in which the target electrical angle θe * changes is the range of the initial electrical angle θset to the predetermined electrical angle (θset−π), but is not limited thereto. The range between the initial electrical angle θset or the electrical angle slightly positive from the initial electrical angle θset and the electrical angle at which the state of the phase current of the motor 22 is different from the state at the initial electrical angle θset. For example, the initial electrical angle θset may be in a range of a predetermined electrical angle (θset−π / 2), or the initial electrical angle θset may be in a range of a predetermined electrical angle (θset−2π / 3). Good. It should be noted that the range in which the target electrical angle θe * changes is preferably as narrow as possible in order to make the moving distance in the longitudinal direction of the vehicle as short as possible.

  In the first to fourth embodiments, the electric vehicles 20 to 20D including the motor 22 that outputs power to the drive shaft 32 have been described. However, as illustrated in the electric vehicle 120 of the modified example of FIG. The present invention may be applied to the electric vehicle 120 in which the engine 122 and the motor 124 are connected to the motor 32 via the planetary gear mechanism 126. In this electric vehicle 120, the engine 122, the motor 124, and the motor 22 are controlled by outputting from the engine 122 power that matches the required power corresponding to the required torque Td * and the power required for charging and discharging the battery 26. The engine 122 is controlled so that all or part of the power output from the engine 122 is output to the drive shaft 32 with torque conversion by the planetary gear mechanism 126, the motor 124, and the motor 22. There are an engine operation mode for controlling the motor 124 and the motor 22 and a motor operation mode for controlling the motor 22 so that the operation of the engine 122 is stopped and power corresponding to the required power is output from the motor 22 to the drive shaft 32. Here, in the case where the control of the first to third embodiments is applied to the electric vehicle 120 instead of the electric vehicles 20 to 20C, in the motor operation mode, the process is the same as that in step S120 of the drive control routine of FIG. Is set to the torque command Tm * of the motor 22, and in the engine operation mode, the torque (direct torque) output from the engine 122 to the drive shaft 32 via the planetary gear mechanism 126 out of the required torque Td * and the required torque Td *. What is necessary is just to set the torque of the difference with Ter to the torque command Tm * of the motor 22. The control of the motor 22 using the torque command Tm * can be performed in the same manner as the control in the first to third embodiments. Further, when the control of the fourth embodiment is applied to the electric vehicle 120 instead of the electric vehicle 20D, the torque command of the motor 22 is performed in the motor operation mode in the same manner as the processing of steps S680 and S760 of the drive control routine of FIG. Tm * is set, and in the engine operation mode, the torque command Tm * of the motor 22 may be set using the difference torque between the required torque Td * and the direct torque Ter instead of the required torque Td * in steps S680 and S760. . The control of the motor 22 using the torque command Tm * can be performed similarly to the control of the fourth embodiment.

  Moreover, it is not limited to what is applied to such a motor vehicle, It is good also as forms of vehicles other than motor vehicles, such as a train. Furthermore, it is good also as a form of the control method of such a vehicle.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the motor 22 corresponds to an “electric motor”, and the state where the absolute value of the rotational speed Nm of the motor 22 is equal to or less than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or greater than the threshold value Tref is a predetermined time. When the rotation stop temperature increase condition that continues over the time is satisfied, the target electrical angle θe that changes in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp as the phase ωp changes. The electronic control unit 40 that executes the drive control routine of FIG. 3 for controlling the motor 22 by setting the d-axis and q-axis current commands Id * and Iq * so that the electrical angle θe of the rotor 22a follows the change of *. It corresponds to “control means”. Further, when the rotation stop temperature rise condition is satisfied, the target electrical angle θe * that changes in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp with the change of the phase ωp. The electronic control unit 40 that executes the drive control routine of FIG. 13 for controlling the motor 22 by setting the torque command Tm * of the motor 22 so that the electrical angle θe of the rotor 22a follows the change also corresponds to “control means”.

  Here, the “electric motor” is not limited to the motor 22 and may be any motor as long as it can output power to the drive shaft connected to the drive wheels. Further, “the condition for increasing the rotation stop temperature is established in which the absolute value of the rotational speed Nm of the motor 22 is equal to or lower than the threshold value Nref and the previous torque command (previous Tm *) of the motor 22 is equal to or higher than the threshold value Tref for a predetermined time. When the phase ωp changes, the electrical angle θe of the rotor 22a changes to the change of the target electrical angle θe * that changes in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp. It is not limited to the control of the motor 22 by setting the d-axis and q-axis current commands Id * and Iq * so as to follow, and when the rotation stop temperature increase condition is satisfied, the phase ωp changes. Thus, the torque of the motor 22 is adjusted so that the electrical angle θe of the rotor 22a follows the change of the target electrical angle θe * that changes in the range of the initial electrical angle θset to the predetermined electrical angle (θset−π) with a period of 2π of the phase ωp. The rotation stop temperature increase condition is satisfied when the rotation stop temperature increase condition is established such that the motor 22 is substantially stopped and the temperature rise of the motor is assumed, such as setting the command Tm * to control the motor 22. As long as the periodic change control for controlling the electric motor is performed so that the electric angle of the electric motor changes at a predetermined cycle within a predetermined angular range including the initial electric angle that is the electric angle of the electric motor at that time. I do not care.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention can be used in the vehicle manufacturing industry.

It is a block diagram which shows the outline of a structure of the electric vehicle 20 as 1st Example of this invention. It is a block diagram centering on the electric system of the electric vehicle 20 of 1st Example. 4 is a flowchart showing an example of a drive control routine executed by the electronic control unit 40. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the map for electric current command setting. It is a flowchart which shows an example of an electric current command setting process. It is explanatory drawing which shows an example of the relationship between phase (omega) p and target electrical angle (theta) e *. It is explanatory drawing which shows an example of the relationship between the d-axis and q-axis temporary current commands Idtmp and Iqtmp and the d-axis and q-axis current commands Id * and Iq *. It is explanatory drawing which shows an example of the relationship between temporary current command Idtmp and Iqtmp of d-axis and q-axis of a modification, and current command Id * and Iq * of d-axis and q-axis. It is a flowchart which shows an example of the electric current command setting process of 2nd Example. It is a flowchart which shows an example of the electric current command setting process of 3rd Example. Time change state of target electrical angle θe *, electrical angle θe, and whether or not to execute periodic change control when there is an obstacle such as a car stop in the direction in which rotor 22a rotates negatively (the vehicle goes down the slope) It is explanatory drawing which shows an example. It is a flowchart which shows an example of the drive control routine of 4th Example. It is a block diagram which shows the outline of a structure of the electric vehicle 120 of a modification.

Explanation of symbols

  20, 20B, 20C, 20D, 120 Electric vehicle, 22 Motor, 22U, 22V Current sensor, 22a Rotor, 22b Stator, 23 Rotation position detection sensor, 24 Inverter, 26 Battery, 30a, 30b Drive wheel, 31 Differential gear, 32 Drive shaft, 40 electronic control unit, 42 CPU, 44 ROM, 46 RAM, 50 ignition switch, 51 shift lever, 52 shift position sensor, 53 accelerator pedal, 54 accelerator pedal position sensor, 55 brake pedal, 56 brake pedal position sensor, 58 Vehicle speed sensor, 122 engine, 124 motor, 126 planetary gear mechanism, D1-D6 diode, Tr1-Tr6 transistor.

Claims (13)

An electric motor capable of outputting power to a drive shaft connected to the drive wheel;
When the rotation stop temperature increase condition for which the motor temperature is substantially stopped and the temperature increase of the motor is assumed is satisfied, an initial electric angle that is an electric angle of the motor when the rotation stop temperature increase condition is satisfied is set. Control means for performing periodic change control for controlling the electric motor so that the electric angle of the electric motor changes in a predetermined cycle including a predetermined angular range,
A vehicle comprising:   The control means sets, as the periodic change control, a target electrical angle that changes the predetermined angle range at the predetermined cycle, and the electrical angle of the motor follows the change of the set target electrical angle. 2. The vehicle according to claim 1, which is means for controlling the electric motor so that is output from the electric motor.   The control means sets a torque command for the electric motor based on a required torque required for the drive shaft, and executes the periodic change control when the d-axis and q-axis are set based on the set torque command. A temporary current command which is a temporary value of the current command is set, and a temporary current command which is an angle based on the ratio between the set d-axis temporary current command and the set q-axis temporary current command and the q-axis An angle is set, a current command angle that is an angle obtained by correcting the set temporary current command angle based on the electrical angle of the motor and the target electrical angle is set, and the d is set based on the set current command angle. 3. The vehicle according to claim 2, wherein the vehicle is a means for setting a current command for an axis and the q-axis, and controlling the electric motor based on the set current command for the d-axis and the q-axis.   The control means, when executing the periodic change control, sets a temporary current command magnitude, which is a temporary value of the magnitude of the current to be supplied to the motor, based on the d-axis and q-axis temporary current instructions. And setting a current command magnitude that is a magnitude obtained by correcting the set temporary current command magnitude based on the electrical angle of the motor and the target electrical angle, and setting the current command magnitude and the setting 4. The vehicle according to claim 3, wherein the vehicle is a means for setting current commands for the d-axis and the q-axis based on the current command angle.   The control means is executing the periodic change control, the target electrical angle is changing in a vehicle downward direction that is a direction in which the vehicle goes down an uphill road, and the target electrical angle is Based on a current command magnitude larger than the set temporary current command magnitude and the set current command angle when it is within a second predetermined angle range including a boundary on the vehicle down direction side of the predetermined angle range 4. The vehicle according to claim 3, which is means for setting current commands for the d-axis and the q-axis.   The control means is executing the periodic change control and the electrical angle of the electric motor is changed when the target electrical angle changes in a vehicle downward direction, which is a direction in which the vehicle goes down an uphill road. Stops following the change in the target electrical angle, and after the interruption, the target electrical angle changes in the vehicle upward direction, which is the direction in which the vehicle goes up the hill, and the target 4. The vehicle according to claim 2, wherein the vehicle is a means for resuming the periodic change control when an electrical angle becomes an angle on the vehicle upward direction side as compared with an electrical angle of the electric motor.   The control means is means for controlling the electric motor so that no current flows through the electric motor when the rotation stop temperature rise condition is satisfied and the execution of the periodic change control is interrupted. 6. The vehicle according to 6.   The control means includes a torque based on a torque required for the drive shaft and a torque for canceling a difference between the electric angle of the electric motor and the target electric angle when the rotation stop temperature increase condition is satisfied. The vehicle according to claim 2, wherein the vehicle is means for setting a sum to a torque command of the electric motor and controlling the electric motor so that the electric motor is driven by the set torque command.   9. The control unit according to claim 1, wherein the control unit is a unit that terminates the periodic change control when an electrical angle of the motor is out of the predetermined angle range during execution of the periodic change control. The vehicle according to any one of claims.   The control means is means for terminating the periodic change control when the accelerator operation amount is larger than a predetermined amount with respect to an initial accelerator operation amount that is an accelerator operation amount when the rotation stop temperature increase condition is satisfied. The vehicle according to any one of claims 1 to 9.   The predetermined angle range is a range having a boundary between the initial electrical angle and a predetermined electrical angle at which the state of the phase current of the motor is different from the state at the initial electrical angle. The vehicle according to any one of claims 10.   The condition for increasing the rotation stop temperature is a condition that is satisfied when a state in which the electric motor is substantially stopped and a torque equal to or higher than a predetermined torque is output from the electric motor continues for a predetermined time. The vehicle according to claim 11. A control method for a vehicle including an electric motor capable of outputting power to a drive shaft connected to a drive wheel,
When the rotation stop temperature increase condition for which the motor temperature is substantially stopped and the temperature increase of the motor is assumed is satisfied, an initial electric angle that is an electric angle of the motor when the rotation stop temperature increase condition is satisfied is set. Performing a periodic change control for controlling the electric motor so that the electric angle of the electric motor changes in a predetermined cycle including a predetermined angle range.
A method for controlling a vehicle.

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