Electric vehicle control device

Abstract

To promptly eliminate upward scattering of a driving motor caused by slip.SOLUTION: A clutch 83 is arranged between a driving motor 3 in which a magnetic pole of a rotor 33 is constituted of a variable magnetic-force magnet 35 and a driving wheel 4R. Target torque control is executed during travelling of an automobile 1. When magnetic-force of the variable magnetic-force magnet 35 is increased during travelling of the automobile 1, first clutch control is changed to second clutch control, so that fastening torque of the clutch 83 is decreased to be matched with required torque, and then magnetic-force increasing control is executed. Thereafter, target power control by which motor torque is controlled is executed so that power output from the driving wheel 4R matches a predetermined target power value.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] The disclosed technology relates to a control device for an electrically powered vehicle capable of running using electric power, such as an electric vehicle or a hybrid vehicle. [Background technology]

[0002] Patent Document 1 discloses a hybrid vehicle equipped with a permanent magnet synchronous drive motor. In this drive motor, a variable magnetic force magnet that can change the magnitude of magnetic force is used as the permanent magnet installed in the rotor.

[0003] The output range of the drive motor is divided into a plurality of magnetized regions, and an optimal magnetic force value (magnetic optimum value) is set for each magnetized region. When the output of the drive motor moves between these magnetized regions, the magnetic force of the variable magnetic magnet is changed to the magnetic optimum value at the destination. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-027615 Summary of the Invention [Problem to be solved by the invention]

[0005] When changing the magnetic force of a variable magnetic force magnet, a large current for magnetization (so-called d-axis current) is applied to the coil of the stator of the drive motor. This causes interference with the drive current (so-called q-axis current) and the torque fluctuates. In other words, the d-axis current is a component that is orthogonal to the q-axis current that generates torque. Therefore, the large current itself is not output as torque, but it interferes with the q-axis current and causes the torque to fluctuate.

[0006] If the change in magnetic force is demagnetization, the torque fluctuates in the direction of decreasing, but if the change in magnetic force is magnetization, the torque fluctuates in the direction of increasing. Therefore, when the magnetic force of the variable magnetic force magnet is changed to the direction of increasing, a high torque is output from the drive motor. In general, the fastening torque of the clutch provided between the drive motor and the drive wheels is higher than the required torque, so that the torque transmitted to the drive wheels may cause a torque shock in the vehicle while it is moving, which may cause the driver to feel uncomfortable.

[0007] One way to suppress such torque shock is to slip the clutch installed between the drive motor and the drive wheels. In other words, even if a high torque is output from the drive motor, slipping the clutch reduces the torque transmitted to the drive wheels, thereby mitigating the torque shock.

[0008] However, when the clutch is slipped, a phenomenon occurs in which the rotation of the drive motor suddenly increases (known as "revving up"). If this revving up phenomenon is not resolved quickly, there is a concern that the clutch may be damaged by frictional heat caused by the slippage.

[0009] The disclosed technology quickly eliminates the racing of the drive motor that accompanies such clutch slippage, and enables a smooth return to an appropriate control state. [Means for solving the problem]

[0010] The disclosed technology relates to a control device for an electric vehicle capable of running using electric power, which is equipped with a drive motor whose rotor poles are composed of variable magnetic magnets whose magnetic force can be changed, and a clutch arranged between the drive motor and drive wheels.

[0011] When the electric vehicle is traveling, target torque control is executed to control the motor torque output by the drive motor so that the motor torque matches a required torque required to be output to the drive wheels.

[0012] When executing magnetization control to change the magnetic force of the magnetic force-variable magnet in a magnetization direction while the electric vehicle is traveling, the magnetization control is executed after changing from first clutch control, which controls the engagement torque of the clutch to be higher than the required torque, to second clutch control, which causes the engagement torque to match the required torque, and after the magnetization control, instead of the target torque control, target power control is executed to control the motor torque so that the power output from the drive wheels matches a predetermined target power value.

[0013] That is, this control device controls an electric vehicle equipped with a drive motor whose rotor poles are formed of a variable magnetic force magnet whose magnetic force can be changed, and changes the magnetic force of the variable magnetic force magnet while the electric vehicle is running.When the electric vehicle is running, target torque control is executed to control the motor torque output by the drive motor so that it matches the required torque required to be output to the drive wheels, and when magnetization control is executed while the electric vehicle is running, a large current is applied to the drive motor.

[0014] When a large current is applied to the drive motor in the magnetization direction, a high torque is output from the drive motor, but before that, the second clutch control is executed to reduce the clutch engagement torque and make it match the required torque. As a result, even if the clutch slips and the motor torque is high, the clutch can output a torque approximately equal to the required torque. This makes it possible to suppress torque shock. Moreover, the driver does not feel uncomfortable.

[0015] Furthermore, after the magnetization control, target power control is executed to control the motor torque so that the power output from the drive wheels coincides with a predetermined target power value. By executing such target power control, the torque output from the drive motor as well as its rotation speed can be converged to a state that satisfies the target power. As a result, the racing phenomenon is eliminated and the drive motor can be restored to its initial output state.

[0016] The control device may also initiate feedback control, during execution of the target power control, for matching the input and output rotation speeds of the clutch based on the input and output rotation speeds.

[0017] During execution of the target power control, the drive motor is torque-controlled, so that the rotation speed of the drive motor changes passively in response to changes in the motor torque. As a result, the rotation speed of the drive motor decreases slowly, so that it takes a relatively long time for the rotation speed to converge. In contrast, if such feedback control is started during execution of the target power control, the torque and rotation speed of the drive motor can be converged quickly. The drive motor can be restored to its initial output state in a shorter time.

[0018] The control device may also be configured such that the clutch is a transmission clutch and, in response to a state of the clutch, the control device switches the gear ratio of the transmission when the clutch is slipping due to the magnetizing control executed after the second clutch control is changed.

[0019] For example, the differential rotation speed, which is the difference between the rotation speed of the input side and the rotation speed of the output side of the slipping clutch, may be compared with a first judgment value, and if it is determined that the differential rotation speed is greater than the first judgment value, the gear ratio of the transmission may be changed so that the differential rotation speed becomes smaller.

[0020] When the rotation speed of the drive motor increases significantly, the slippage of the transmission clutch also increases accordingly. When the slippage increases, the amount of heat generated by friction also increases, and the amount of wear on the clutch also increases. This reduces the durability of the clutch, and in some cases, the clutch may be damaged.

[0021] On the other hand, if the gear ratio of the transmission is changed so that the differential speed becomes smaller based on a predetermined condition when the clutch of the transmission is slipping, the clutch slip can be reduced, thereby reducing the load on the clutch and improving the durability of the clutch.

[0022] The control device may also be configured so that the transmission has a plurality of the clutches, and when it compares the temperature of a slipping clutch with a second determination value and determines that the temperature of the clutch is higher than the second determination value, it switches the gear ratio of the transmission so that the clutch is changed.

[0023] If the temperature of the clutch becomes excessively high and continues for a long time, the durability of the clutch will decrease. In response to this, if the gear ratio of the transmission is changed so that the clutch is changed based on a specified condition, the high temperature clutch will not slip, so damage to the clutch can be suppressed. Therefore, the durability of the clutch can be improved. Effect of the Invention

[0024] The disclosed technology can suppress torque shock caused by clutch slippage, and can quickly eliminate the sudden increase in speed of the drive motor that occurs at the time, thereby reducing discomfort felt by the driver. [Brief description of the drawings]

[0025] [Figure 1] 1 is a schematic diagram showing the main configuration of an automobile to which the disclosed technology is applied. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing the configuration of a drive motor. [Diagram 3] FIG. 2 is a block diagram showing an MCU and its associated main input / output devices. [Figure 4] FIG. 4 is a diagram illustrating an example of an output range of a drive motor. [Diagram 5] FIG. 2 is a simplified system diagram relating to control of a drive motor. [Figure 6] 5 is a flowchart showing an example of control of a drive motor. [Figure 7] 5 is a flowchart showing a flow of main processes of magnetic force change control. [Figure 8] 11A and 11B are diagrams for explaining the occurrence of a torque shock. [Figure 9]FIG. 2 is a block diagram showing the TCU and its associated major input / output devices. [Figure 10] FIG. 1 is a diagram for explaining the blowing up phenomenon. [Figure 11] FIG. 4 is a diagram for explaining target power control and feedback control. [Figure 12] 5 is a flowchart showing a flow of main processes during magnetic force change control (magnetization control) to which the disclosed technology is applied. [Figure 13] 13 is a flowchart showing an example of control in Application Example 1. [Figure 14] FIG. 4 is a diagram for explaining switching of the gear ratio of the transmission. [Figure 15] 13 is a flowchart showing an example of control in Application Example 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] The disclosed technology will now be described, however, the following description is merely exemplary in nature.

[0027] <Electric vehicles> FIG. 1 shows an automobile 1 (an example of an electric vehicle) to which the disclosed technology is applied. The automobile 1 is a hybrid vehicle capable of running on electric power. The automobile 1 is equipped with an engine 2 and a drive motor 3 as its drive source. These work together to drive two wheels (drive wheels 4R) located symmetrically on the left and right of the four wheels 4F, 4F, 4R, 4R. This causes the automobile 1 to run. Note that the automobile 1 may be an electric vehicle equipped with only the drive motor 3. The automobile 1 may also be a four-wheel drive vehicle.

[0028] In the case of this automobile 1, the engine 2 is disposed at the front of the vehicle body, and the drive wheels 4R are disposed at the rear of the vehicle body. In other words, this automobile 1 is a so-called FR vehicle. Furthermore, in the case of this automobile 1, the engine 2 is the main driving source rather than the drive motor 3, and the drive motor 3 is used to assist the driving of the engine 2 (a so-called mild hybrid). The drive motor 3 is also used not only as a driving source, but also as a generator during regeneration.

[0029] In addition to an engine 2 and a drive motor 3, the automobile 1 is equipped with a first intermediate clutch 5, an inverter 6, a second intermediate clutch 7, a transmission 8, a differential gear 9, a battery 10, and the like as drive system devices. The automobile 1 is also equipped with an engine control unit (ECU) 20, a motor control unit (MCU) 21, a transmission control unit (TCU) 22, a brake control unit (BCU) 23, a general control unit (GCU) 24, and the like as control system devices. An engine revolution sensor 50, a motor revolution sensor 51, a current sensor 52, a magnetic sensor 53, an accelerator sensor 54, a transmission sensor 55, and the like are also installed in the automobile 1 in association with the control system devices.

[0030] (Drive system device) The engine 2 is an internal combustion engine that burns gasoline as fuel. The engine 2 is also a so-called four-stroke engine that generates rotational power by repeating cycles of intake, compression, expansion, and exhaust. There are various types and forms of the engine 2, such as a diesel engine, but the technology disclosed herein is not particularly limited to the type or form of the engine.

[0031] In this automobile 1, the engine 2 is disposed in the approximate center in the vehicle width direction with the output shaft that outputs rotational power facing the front-rear direction of the vehicle body. The automobile 1 is equipped with various devices and mechanisms associated with the engine 2, such as an intake system, an exhaust system, and a fuel supply system, but these are not shown and will not be described.

[0032] The drive motor 3 is disposed in series behind the engine 2 via a first intermediate clutch 5. The drive motor 3 is a permanent magnet type synchronous motor that is driven by three-phase AC. As shown in a simplified form in Fig. 2, the drive motor 3 is mainly composed of a motor case 31, a shaft 32, a rotor 33, a stator 34, etc.

[0033] Motor case 31 is a container having a cylindrical space therein with its front and rear end faces sealed, and is fixed to the body of automobile 1. Rotor 33 and stator 34 are housed in motor case 31. Shaft 32 is axially supported by motor case 31 so as to be freely rotatable, with its front and rear ends protruding from motor case 31.

[0034] A first intermediate clutch 5 is provided so as to be interposed between a front end of the shaft 32 and an output shaft of the engine 2. The first intermediate clutch 5 is configured to be switchable between a state in which the output shaft and the shaft 32 are connected (engaged state) and a state in which the output shaft and the shaft 32 are separated (unengaged state).

[0035] A second intermediate clutch 7 is provided so as to be interposed between the rear end of the shaft 32 and the input shaft of the transmission 8. The second intermediate clutch 7 is configured to be switchable between a state in which the shaft 32 and the input shaft of the transmission 8 are connected (engaged state) and a state in which the shaft 32 and the input shaft of the transmission 8 are separated (disengaged state).

[0036] The rotor 33 is a cylindrical member formed by laminating multiple metal plates each having an axial hole in the center. The rotor 33 is integrated with the shaft 32 by fixing the middle part of the shaft 32 to the axial hole of the rotor 33.

[0037] Magnets 35 are installed around the entire outer periphery of rotor 33. Magnets 35 are configured so that different magnetic poles, i.e., S poles and N poles, are alternately arranged at equal intervals in the circumferential direction. Magnet 35 may be configured as one cylindrical magnet having multiple magnetic poles, or may be configured as multiple arc-shaped magnets that make up each magnetic pole.

[0038] Furthermore, in this drive motor 3, the magnet 35 is configured so that the magnitude of the magnetic force can be changed between large and small (variable magnetic force magnet 35). Normally, a magnet (permanent magnet) with large coercive force (resistance) and capable of retaining its magnetic force for a long period of time is used in this type of drive motor 3. In this drive motor 3, a permanent magnet with small coercive force is used as the variable magnetic force magnet 35 so that the magnetic force can be changed relatively easily.

[0039] There are various types of permanent magnets, such as ferrite magnets, neodymium magnets, samarium-cobalt magnets, and alnico magnets, and they have various holding forces. The type and material of the variable magnetic force magnet 35 can be selected according to the specifications and are not particularly limited.

[0040] A cylindrical stator 34 (inner rotor type) is installed around the rotor 33 with a small gap between them. The stator 34 has a stator core 34a formed by laminating multiple metal plates, and multiple coils 36 formed by winding electric wires around the stator core 34a.

[0041] The stator core 34a is provided with a plurality of teeth 34b that radiate inward, and a plurality of coils 36 are formed by winding electric wire around these teeth 34b in a predetermined order. These coils 36 constitute a three-phase coil group consisting of U-phase, V-phase, and W-phase. To supply electricity to these coils 36, a connection cable 36a is led out from each of the coil groups of each phase to the outside of the motor case 31.

[0042] These connection cables 36a are connected to a battery 10 mounted on the vehicle as a driving power source via an inverter 6. In the case of this vehicle 1, the battery 10 is a DC battery with a rated voltage of 50V or less, specifically 48V.

[0043] The battery 10 supplies DC power to the inverter 6. The inverter 6 converts the DC power into three-phase AC and supplies it to the drive motor 3. This rotates the rotor 33, and the power (rotational power) of the drive motor 3 is output to the transmission 8 via the shaft 32 and the second relay clutch 7.

[0044] In the case of this automobile 1, the transmission 8 is a multi-stage automatic transmission (so-called AT). As shown in Fig. 1, the transmission 8 has an input shaft 80 at one end, which is connected to the second intermediate clutch 7. The other end of the transmission 8 has an output shaft 81 which rotates independently of the input shaft 80. A transmission mechanism consisting of a plurality of planetary gear mechanisms 82 and a plurality of transmission clutches 83 (including brakes) is assembled between the input shaft 80 and the output shaft 81.

[0045] By switching these speed change mechanisms, it is possible to switch between forward and reverse, and to change the rotation speed between the input shaft 80 and the output shaft 81 of the transmission 8 to a different speed, that is, to change the gear ratio.

[0046] For example, an input side 83a of each transmission clutch 83 is configured to be connectable to an input shaft 80. An output side 83b of each transmission clutch 83 is connected to an output shaft 81 via a corresponding planetary gear mechanism 82. When a specific transmission clutch 83 is selected and engaged, the input shaft 80 and output shaft 81 of the transmission are connected via the transmission clutch 83 and the corresponding planetary gear mechanism 82. This changes the gear ratio, etc.

[0047] The output shaft 81 is connected to a differential gear 9 via a propeller shaft 11 that extends in the front-rear direction of the vehicle body and is arranged coaxially with the output shaft 81. A pair of drive shafts 13, 13 that extend in the vehicle width direction and are connected to the left and right drive wheels 4R, 4R are connected to the differential gear 9. The rotational power output through the propeller shaft 11 is distributed by the differential gear 9 and then transmitted to each drive wheel 4R through the pair of drive shafts 13, 13. A brake 14 is attached to each of the wheels 4F, 4F, 4R, 4R to brake their rotation.

[0048] (Control system equipment) In order to control the running of the automobile 1 in response to the driver's operation, the above-mentioned units, ECU 20, MCU 21, TCU 22, BCU 23, and GCU 24, are installed in the automobile 1. Each of these units is composed of hardware such as a processor, memory, and interface, and software such as a database and a control program.

[0049] The ECU 20 is a unit that mainly controls the operation of the engine 2. The MCU 21 is a unit that mainly controls the operation of the drive motor 3. The TCU 22 is a unit that mainly controls the operation of the transmission 8. The BCU 23 is a unit that mainly controls the operation of the brake 14. The GCU 24 is electrically connected to the ECU 20, MCU 21, TCU 22, and BCU 23, and is a higher-level unit that comprehensively controls these.

[0050] The "control device" in the disclosed technology is composed of these units. In particular, the MCU 21, which mainly controls the operation of the drive motor 3, and the TCU 22, which mainly controls the operation of the transmission 8, constitute the main components of the control device. These units work together to execute target power control, which will be described later.

[0051] The engine revolution sensor 50 is attached to the engine 2, detects the revolution speed of the engine 2, and outputs the detected revolutions to the ECU 20. The motor revolution sensor 51 is attached to the drive motor 3, and detects the revolution speed and rotation position of the drive motor 3, and outputs the detected revolutions to the MCU 21. The current sensor 52 is attached to the connection cable 36a, and detects the value of the current flowing through each coil 36, and outputs the detected revolutions to the MCU 21.

[0052] The magnetic sensor 53 is attached to the drive motor 3, and detects the magnetic force of the variable magnetic magnet 35, and outputs the result to the MCU 21. The accelerator sensor 54 is attached to the accelerator pedal (accelerator pedal 15) that the driver depresses when driving the automobile 1, and detects the accelerator opening degree corresponding to the output required to drive the automobile 1, and outputs the result to the ECU 20. The transmission sensor 55 detects the rotation speed and engagement torque of each transmission clutch 83, the rotation speed of the output shaft 81, and the like, and outputs the result to the TCU 22.

[0053] Based on the detection value signals input from these sensors, each unit cooperates to control each device in the drive system, thereby running the automobile 1. For example, when the automobile 1 runs using the driving force of the engine 2, the ECU 20 controls the operation of the engine 2 based on the detection values ​​of the accelerator sensor 54 and the engine revolution sensor 50.

[0054] Then, the TCU 22 controls the first intermediate clutch 5 and the second intermediate clutch 7 to be in an engaged state. When braking the automobile 1, the BCU 23 controls each brake 14. When braking by regeneration, the TCU 22 controls the first intermediate clutch 5 to be in a disengaged state or a partially engaged state, and controls the second intermediate clutch 7 to be in an engaged state. Then, the MCU 21 controls the drive motor 3 to generate electricity and recover the electricity to the battery 10.

[0055] <Drive motor control> The MCU 21 controls the automobile 1 to run using the power output by the drive motor 3, either with the drive motor 3 outputting alone or with the output of the engine 2 being assisted as necessary.

[0056] Specifically, the ECU 20 sets the torque to be output by the engine 2 based on the detected values ​​of the accelerator sensor 54, the engine revolution sensor 50, etc. In accordance with this, the GCU 24 sets a torque demand (demanded torque) for the drive motor 3 within a predetermined output range in accordance with a preset output distribution ratio between the engine 2 and the drive motor 3. The MCU 21 controls the drive motor 3 so that the requested torque is output.

[0057] 3 shows the MCU 21 and its related main input / output devices. The MCU 21 is provided with a motor output control unit 21a and a magnetization control unit 21b as functional components, which are implemented by hardware and software. The motor output control unit 21a has a function of controlling the drive of the drive motor 3, and controls the drive current flowing through the coil 36 to cause the drive motor 3 to output the required power.

[0058] On the other hand, the magnetization control unit 21b has a function of increasing the power factor of the drive motor 3, and changes the magnetic force of the variable magnetic force magnet 35 by controlling the magnetization current flowing through the coil 36. Specifically, the magnetic force of the variable magnetic force magnet 35 is changed so that the magnetic force of the variable magnetic force magnet 35 approximately matches the electromagnetic force generated in the coil 36 by the drive current.

[0059] The power factor is the ratio of effective power (power actually consumed) to apparent power (power supplied to the drive motor 3). If the power factor is low, a large current must be passed to obtain the same output, and the motor must be accordingly larger. Therefore, by increasing the power factor of the drive motor 3, the drive motor 3 can be made lighter and more compact. Furthermore, if the power factor is increased, the power generation during regeneration can also be increased.

[0060] (Drive motor output range) 4 illustrates an example of the output range of the drive motor 3. The output range is defined by an upper load line indicating the upper limit of the torque (load) for each rotation speed.

[0061] Specifically, in the low RPM range up to a certain RPM (r1), the upper limit of the torque is kept at a maximum (T2). In the medium and high RPM ranges, where the RPM is higher than the low RPM range, the upper limit of the torque is gradually decreased until the RPM reaches the upper limit (r2).

[0062] Data such as maps and tables that define such output ranges are preset in the MCU 21. The motor output control unit 21a controls the drive motor 3 within the output range by referring to the data.

[0063] Furthermore, the output range of the drive motor 3 is divided into a plurality of magnetized regions. The magnetization control unit 21b is configured to change the magnetic force of the variable magnetic magnet 35 in accordance with each of these magnetized regions.

[0064] 4, in this embodiment, the output range of the drive motor 3 is divided into four magnetized regions Rm, namely, first to fourth magnetized regions Rm. Specifically, the output range is divided into a first magnetized region Rm1 with a high load that is biased toward the low rotation side and includes a maximum torque value T2, a second magnetized region Rm2 that spreads from the low rotation side to the high rotation side and has a torque peak at medium rotation at a lower load than the first magnetized region Rm1, a third magnetized region Rm3 with a torque peak shifted to the high rotation side at a lower load than the second magnetized region Rm2, and a fourth magnetized region Rm4 with a lower load than the third magnetized region Rm3 and including a torque (torque that does not contribute to the running of the automobile 1) T1 at which the drive motor 3 runs idle.

[0065] In each of the magnetized regions Rm, an optimal magnetic force value (magnetic force optimum value) that achieves a high power factor is set in correspondence with the respective output. For example, in the first magnetized region Rm1, the magnetic force of the variable magnetic force magnet 35 in the initial state is set as the magnetic force optimum value (first magnetic force optimum value). In the second magnetized region Rm2, a magnetic force optimum value lower than the first magnetic force optimum value is set (second magnetic force optimum value). In the third magnetized region Rm3, a third magnetic force optimum value lower than the second magnetic force optimum value is set, and in the fourth magnetized region Rm4, a fourth magnetic force optimum value lower than the third magnetic force optimum value is set.

[0066] The magnetization control unit 21b predicts the optimal magnetized region Rm based on the driving state of the automobile 1, and when the magnetized region Rm transitions to another adjacent magnetized region Rm, changes the magnetic force of the magnetic force variable magnet 35 to a magnetic force optimal value corresponding to the magnetized region Rm. For example, when transitioning from the first magnetized region Rm1 to the second magnetized region Rm2, a demagnetization process is executed in the drive motor 3, and the magnetic force of the magnetic force variable magnet 35 is changed from the first magnetic force optimal value to the second magnetic force optimal value.

[0067] Also, for example, when transitioning from the third magnetization region Rm3 to the second magnetization region Rm2, a magnetization process is executed in the drive motor 3, and the magnetic force of the variable magnetic force magnet 35 is changed from the third magnetic force optimum value to the second magnetic force optimum value.

[0068] (Specific example of drive motor control) FIG. 5 shows a simplified system diagram relating to the control of the drive motor 3. FIG. 6 shows an example of the control of the drive motor 3 performed by the MCU 21. With reference to these diagrams, a specific flow of control of the drive motor 3 will be described. Note that the drive motor 3 is driven by a torque current command Iq * and excitation current command Id * It is controlled by vector control using

[0069] When the automobile 1 is in a state in which it can run, the MCU 21 constantly receives detection values ​​from the current sensor 52, the motor rotation sensor 51, and the magnetic sensor 53 (step S1). Similarly, the ECU 20 constantly receives detection values ​​from the accelerator sensor 54 and the engine rotation sensor 50.

[0070] The GCU 24 obtains the detection value of the accelerator sensor 54 from the ECU 20, and sets the torque (required torque) required of the drive motor 3 out of the torque to be output to the drive wheels 4R in accordance with a preset distribution ratio of the output between the engine 2 and the drive motor 3. The GCU 24 issues a command (torque command value T * ) to MCU 21.

[0071] That is, the MCU 21 controls the output of the drive motor 3 based on a predetermined target torque (so-called target torque control). Through target torque control, the torque (motor torque) output by the drive motor 3 is controlled to match the target torque. Therefore, when the above-mentioned command is input while the automobile 1 is running, the MCU 21 controls the drive motor 3 with the required torque as the target torque. Through target torque control of the drive motor 3, the automobile 1 runs in accordance with the driver's request.

[0072] Also, while the automobile 1 is running, as described above, the target torque control is interrupted when the magnetized region Rm is shifted, and control is executed to apply a high voltage to the coil 36 of the drive motor 3 (magnetic force change control). The magnetic force of the magnetic force variable magnet 35 is changed by the magnetic force change control.

[0073] Specifically, the MCU 21 (motor output control unit 21a) calculates a torque command value T * When the command Idq is input (Yes in step S2), a command (drive current command value Idq) is output to output the amount of change in the drive current (torque current component) that generates the torque. *) (step S3). In addition, the MCU 21 (magnetization control unit 21b) executes a calculation process of a command (magnetization state command value Φ * ) (step S4). The magnetization control unit 21b executes the calculation process of the magnetization state command value Φ * Based on this, a command (magnetic current command value Idq) that outputs a torque current component corresponding to the change in magnetic force of the magnetic variable magnet 35 is generated. * ) is calculated (step S5).

[0074] The MCU 21 calculates the drive current command value Idq * and magnetic current command value Idq * Based on this, it is determined whether or not the magnetic force of the magnetic force variable magnet 35 needs to be changed (step S6). For example, as described above, if the magnetized region Rm transitions to another magnetized region Rm when the requested torque is output, it is determined that the magnetic force of the magnetic force variable magnet 35 needs to be changed, and if the magnetized region Rm is located in the same magnetized region Rm even when the requested torque is output, it is determined that the magnetic force of the magnetic force variable magnet 35 does not need to be changed.

[0075] If the MCU 21 determines that it is not necessary to change the magnetic force of the magnetic force variable magnet 35, it determines whether the output torque is greater than the torque T1 at which the drive motor 3 runs idle (step S7). If the output torque is greater than the torque T1, the MCU 21 controls the drive motor 3 by normal vector control.

[0076] That is, the motor output control unit 21a outputs a command (voltage command value Vuvw * ) is calculated (step S8). Then, a switching command value is calculated by PWM control (step S9).

[0077] The switching command value is output to the inverter 6 through a driver circuit, whereby multiple switching elements are controlled to be turned on and off inside the inverter 6. As a result, a predetermined three-phase AC (drive current) is passed through each coil group, and the drive motor 3 rotates with the required torque (step S10).

[0078] On the other hand, when the MCU 21 determines that the magnetic force of the magnetic force variable magnet 35 needs to be changed (No in step S6), the magnetization control unit 21b executes magnetic force change control (step S11).

[0079] Furthermore, even if the MCU 21 determines that it is not necessary to change the magnetic force of the magnetic force variable magnet 35, if it determines that the output torque is equal to or less than the torque T1 at which the drive motor 3 runs idle (No in step S7), the magnetization control unit 21b executes magnetic force change control (step S11).

[0080] That is, when the required amount of rotational power of the drive motor 3 becomes almost 0 (zero), the magnetic force of the variable magnetic magnet 35 is changed (reset) to the initial state. In the case of the automobile 1, for example, there are cases where the accelerator pedal 15 is suddenly depressed from an idling state or a stopped state, causing rapid acceleration.

[0081] In the case of the variable magnetic force magnet 35, the magnetic force in the initial state is set high to match the high load, so by resetting the magnetic force during idle operation, the drive motor 3 can be driven appropriately even when such rapid acceleration is performed.

[0082] 7 shows a flow of main processing of the magnetic force change control. When the magnetic force change control is requested, the magnetization control unit 21b calculates a magnetization state command value Φ * Based on this, the direction of the magnetization process is determined. That is, it is determined whether to execute a process to increase the magnetic force of the magnetic force variable magnet 35 (magnetization process) or to execute a process to decrease the magnetic force of the magnetic force variable magnet 35 (demagnetization process). The magnetization control unit 21b further specifies the amount of change in the magnetic force that is increased or decreased.

[0083] Then, the magnetization control unit 21b determines whether the position (position in the direction of rotation) of the rotor 33 relative to the stator 34 is suitable for the magnetization process based on the detection value of the motor rotation sensor 51 (step S21), and outputs a magnetization current when the rotor 33 is in an appropriate position (step S22). The magnetization current is a pulsed current that generates an electromagnetic force larger than the coercive force of the variable magnetic force magnet 35. The directions of the magnetic field lines of the electromagnetic force are opposite between the magnetization process and the demagnetization process.

[0084] The magnetization control unit 21b controls the magnetic force of the variable magnetic magnet 35 to be equal to or greater than the magnetization state command value Φ * (step S23), and executes the magnetization process until the magnetic force of the variable magnetic force magnet 35 becomes substantially the same as the magnetic force optimum value. When resetting the magnetic force of the variable magnetic force magnet 35, executes the magnetization process until the magnetic force becomes substantially the same as the initial magnetic force.

[0085] Then, when the magnetic force of the variable magnetic force magnet 35 becomes substantially the same as the optimum magnetic force value or the initial magnetic force, the magnetic force change control is terminated, and the drive motor 3 is controlled by normal vector control as shown in FIG. 6 (steps S8 to S10).

[0086] <Clutch slip> As described above, in this automobile 1, the magnetic force change control is executed even when the automobile 1 is running. If the magnetic force change control in the direction of increasing magnetism (magnetization control) is executed while the automobile 1 is running, a torque shock may occur in the traveling automobile 1, causing a sense of discomfort to the driver.

[0087] The upper diagram of FIG. 8 illustrates an example of the change over time in motor torque Tm during magnetization control. In this example, magnetization control is executed during the period from time t1 to t1'. The period from t1' to t2 is a period in which the change in magnetic force is confirmed and control (learning control) is executed to learn the driving current value (the value of the q-axis current) so that it corresponds to the magnetic force after magnetization, thereby making the motor torque Tm match the required torque. The learning control is a control that accompanies the magnetization control and is included in the magnetization control. Ta is the required torque. While the automobile 1 is traveling, the drive motor 3 is under target torque control, so the motor torque Tm before the magnetization control is executed matches the required torque Ta.

[0088] Tt is the clutch engagement torque in the transmission 8. The clutch engagement torque Tt is the engagement torque of the transmission clutch 83 that connects the input shaft 80 and the output shaft 81 of the transmission 8, and corresponds to the torque that the transmission clutch 83 can transmit to its output side 83b. In order to reliably transmit the motor torque Tm to the drive wheels, the clutch engagement torque Tt is usually controlled (first clutch control) to be higher than the required torque Ta.

[0089] During magnetization control, a magnetization current (d-axis current) is passed through the coil 36 to generate a large electromagnetic force. This causes a high voltage that is much higher than the drive voltage to be applied to the drive motor 3. Therefore, as shown in the upper diagram of FIG. 8, during magnetization control, a high peak-shaped motor torque Tm that is much higher than the required torque Ta is output from the drive motor 3. As a result, a torque shock occurs in the traveling automobile 1, which may cause the driver to feel uncomfortable.

[0090] In order to suppress such torque shock, in this automobile 1, the MCU 21 cooperates with the TCU 22 to slip the transmission clutch 83 during magnetization control (including the associated learning control). Specifically, the clutch engagement torque Tt is controlled to match the required torque Ta (second clutch control).

[0091] FIG. 9 shows the TCU 22 and its related main input / output devices. The TCU 22 is provided with an intermediate clutch control unit 22a and a transmission clutch control unit 22b as functional components, which are provided by the hardware and software. The intermediate clutch control unit 22a controls the operation of each of the first intermediate clutch 5 and the second intermediate clutch 7. The transmission clutch control unit 22b controls the operation of each of the transmission clutches 83. The first clutch control and the second clutch control are executed by the transmission clutch control unit 22b.

[0092] When the transmission clutch control unit 22b acquires information related to the execution of magnetic force change control from the GCU 24, it controls the operation of the transmission clutch 83 being used accordingly. Specifically, as shown in the lower diagram of FIG. 8, the transmission clutch control unit 22b switches from the first clutch control to the second clutch control immediately before (time t0) the start of the magnetization control (time t1). This reduces the clutch engagement torque Tt. As a result, the transmission clutch 83 slips.

[0093] At this time, the clutch engagement torque Tt is controlled to match the required torque. By executing the second clutch control, even if a high motor torque Tm is output from the drive motor 3, torque exceeding the required torque is not transmitted to the drive wheels 4R. As a result, torque shock can be suppressed.

[0094] (Issues with second clutch control) When the transmission clutch 83 is caused to slip, a phenomenon occurs in which the rotation of the drive motor 3 increases suddenly (so-called "revving up").

[0095] 10 shows the relationship between the motor torque Tm and the motor rotation speed Rm during magnetization control. Note that since the output of the engine 2 is not taken into consideration here, the motor rotation speed Rm is also the rotation speed of the input shaft 80 of the transmission 8.

[0096] Before the magnetization control is executed, the drive motor 3 rotates at a predetermined rotation speed Ra. At this time, the transmission clutch 83 being used is engaged, so both the input side 83a and the output side 83b of the transmission clutch 83 also rotate at the rotation speed Ra. The output shaft 81 of the transmission 8 rotates at a rotation speed changed by the planetary gear mechanism 82 corresponding to the transmission clutch 83.

[0097] As shown in Fig. 10, when the transmission clutch 83 is slipped during magnetization control, the drive motor 3 goes into an idling state, and the motor rotation speed Rm suddenly increases from the rotation speed Ra corresponding to the required torque Ta. The motor rotation speed Rm further increases during learning control, and remains high. If this racing phenomenon is not resolved quickly, the transmission clutch 83 may be damaged by frictional heat caused by the slip.

[0098] Furthermore, in the target torque control, the motor torque is controlled so that it matches the target torque (required torque) according to the rotation speed at that time. Therefore, after the rotation speed increases due to the racing phenomenon, the rotation speed is maintained. In other words, the racing phenomenon cannot be eliminated by the conventional target torque control alone.

[0099] A possible measure to quickly eliminate the racing phenomenon is to increase the clutch engagement torque, which was set to match the required torque, immediately after the magnetization control. This reduces the slippage, which in turn reduces the motor rotation speed Rm, eliminating the racing phenomenon. However, this causes a reaction, which is that a high motor torque is transmitted to the drive wheel 4R, which causes a torque shock.

[0100] As another countermeasure, it is possible to reduce the target torque in the target torque control to be smaller than the required torque immediately after the magnetization control, thereby reducing the motor torque itself. This will reduce the motor rotation speed Rm, thereby eliminating the racing phenomenon.

[0101] However, this may cause the motor rotation speed Rm to drop below the initial rotation speed Ra. In this case, even if the motor torque returns to the required torque by the target torque control after the revving phenomenon is resolved, the motor rotation speed Rm will not return to the initial state. There is a concern that the driver may feel uncomfortable due to insufficient power of the drive motor 3.

[0102] Therefore, in this control device, the control of the drive motor 3 after the magnetization control is devised so as to quickly eliminate the increase in speed of the drive motor 3 caused by slippage of the transmission clutch 83 and smoothly return to the control state immediately before the magnetization control.

[0103] Specifically, following the magnetization control, target power control is executed to control the motor torque so that the power output from the drive motor 3 coincides with a predetermined target power. Furthermore, during execution of the target power control, feedback control is started to match the rotation speeds of the input side 83a and the output side 83b of the transmission clutch 83 based on the rotation speeds of these sides.

[0104] (Target power control) In the target power control, torque control is executed so that the power output from the drive wheel 4R, that is, the multiplication value of the torque T and the rotation speed R of the drive wheel 4R, becomes a target power value (target power value). The target power value is a value that converges to the current power of the drive wheel 4R, and may be, for example, the multiplication value of the current required torque of the drive wheel 4R and the corresponding rotation speed of the drive wheel 4R.

[0105] In the target power control, torque control is executed with the motor torque Tm corresponding to the target power value as the target torque, not the required torque. If the target power value is constant, when the motor rotation speed Rm is high, such as at the peak of the racing phenomenon, the target torque is accordingly lowered, and when the racing phenomenon weakens and the motor rotation speed Rm decreases, the target torque is increased.

[0106] 11 shows the relationship between motor torque Tm and motor rotation speed Rm during and after magnetization control when target power control and feedback control are performed. As described above, Rm is the rotation speed of the input shaft 80 of the transmission 8, and is also the rotation speed of the input side 83a of the transmission clutch 83 being used. Ta is the required torque immediately before magnetization control, and Ra is the motor rotation speed Rm immediately before magnetization control.

[0107] As in FIG. 8 etc., magnetization control (including learning control) is executed during the period from time t1 to t2. During this period, as described above, high motor torque Tm is output from the drive motor 3. Correspondingly, the first clutch control is changed to the second clutch control immediately before time t1 (timing of time t0). As a result, when magnetization control is executed, the motor rotation speed Rm increases rapidly according to the motor torque Tm (revving phenomenon). Note that the rotation speed of the output shaft 81 of the transmission 8 and the output side 83b of the transmission clutch 83 connected thereto are maintained at Ra due to high inertia force, even when magnetization change control is executed.

[0108] At this time, the second clutch control causes the clutch engagement torque Tt to coincide with the required torque Ta at the timing immediately before the magnetization control. As a result, even if a high motor torque Tm is output by the magnetization control, a torque substantially equal to the required torque Ta is output to the downstream side of the transmission clutch 83, so that torque shock can be suppressed. The rotation speed of the output side 83b of the transmission 8 is also maintained at Ra, so the driver does not feel uncomfortable.

[0109] Then, at the timing of time t3 after the magnetization control, specifically the learning control, is ended, the target torque control is switched to the target power control. That is, the target power control is started from the time t3. In the target power control, as described above, the torque control is executed by the target torque corresponding to the target power value.

[0110] As a result, the motor torque Tm decreases and the motor rotation speed Rm also decreases. However, the motor rotation speed Rm at this time changes passively in response to the change in torque. Therefore, the motor rotation speed Rm decreases gradually as shown by the imaginary line Rf. Therefore, it takes a relatively long time to converge to the initial rotation speed Ra.

[0111] Therefore, in cooperation with the TCU 22 (transmission clutch control unit 22b), while the target power control is being executed, the MCU 21 starts feedback control to match these rotation speeds based on the difference (differential rotation speed) between the rotation speed of the input side 83a and the rotation speed of the output side 83b of the transmission clutch 83 being used.

[0112] Specifically, a predetermined reference value for the differential rotation speed is set in the TCU 22. As described above, in Fig. 11, the rotation speed on the upstream side of the transmission clutch 83 is the same as the motor rotation speed Rm, and the rotation speed on the downstream side of the transmission clutch 83 is the same as the initial rotation speed Ra. Therefore, the difference between these rotation speeds corresponds to the differential rotation speed, and in Fig. 11, ΔR is set in the TCU 22 as the reference value.

[0113] The TCU 22 compares the differential rotation speed, which is actually measured or estimated based on the detection value of the transmission sensor 55, with the reference value. If the TCU 22 determines that the differential rotation speed is less than the reference value (timing of time t4 in FIG. 11), it starts feedback control of the rotation speed of the transmission clutch 83 so that the differential rotation speed becomes "0", that is, so that the rotation speed of the input side 83a of the transmission clutch 83 matches the rotation speed of the output side 83b of the transmission clutch 83.

[0114] In the feedback control, the rotation speed, which is different from the torque, is controlled. Therefore, if the feedback control is started at the same time as the target power control based on the torque control, the control may become unstable and vibrations may occur. By starting the feedback control during the execution of the target power control (after the start of the target power control), such a problem can be prevented.

[0115] When the feedback control is started, the gain of the torque control is adjusted according to the differential rotation speed so that the differential rotation speed quickly becomes "0". This allows the motor torque Tm and the motor rotation speed Rm to quickly converge to Ta and Ra. In FIG. 11, at the timing of time t5, the motor torque Tm and the motor rotation speed Rm return to their initial states. The slip of the transmission clutch 83 that has occurred since time t1 is also eliminated.

[0116] After that, the TCU 22 also changes the clutch engagement torque Tt to a normal value (at time t6). That is, the control mode is changed from the second clutch control to the first clutch control. As a result, the operating states of the drive motor 3 and the transmission 8 are restored to the states before the magnetization control.

[0117] (Specific example of control of the drive motor 3 and the transmission clutch 83 related to the magnetization control) 12 shows an example of a flowchart related to the execution of magnetization control, etc. The MCU 21 determines whether or not the magnetization control is to be executed (step S30). If it is determined that the magnetization control is to be executed, the TCU 22 changes the control from the first clutch control to the second clutch control as described above (step S31).

[0118] When the second clutch control is started, the MCU 21 starts magnetizing control (step S32). Then, when the magnetizing control ends (Yes in step S33), the learning control associated therewith starts (step S34). Then, when the learning control ends (Yes in step S35), the MCU 21 interrupts the target torque control and starts the target power control (step S36).

[0119] When the differential rotation speed becomes less than the reference value ΔR as a result of the target power control (Yes in step S37), feedback control is started (step S38). Then, when the differential rotation speed becomes zero, that is, when the rotation speeds on the upstream side and downstream side of the transmission clutch 83 being used match, the target power control and feedback control are ended, and the target torque control is resumed (steps S39, S40).

[0120] Through this series of processing, the racing phenomenon is eliminated, and the motor torque Tm and the motor rotation speed Rm are restored to the states before the execution of the magnetization control, whereby the TCU 22 changes from the second clutch control to the first clutch control (step S41).

[0121] In this way, with a control device to which the disclosed technology is applied, even if magnetization control that generates a motor torque Tm higher than the required torque is performed while the automobile 1 is running, the torque shock can be suppressed by second clutch control. Furthermore, the speed increase phenomenon of the drive motor 3 that occurs due to slippage of the transmission clutch 83 can be quickly eliminated by target power control and feedback control, allowing a smooth return to an appropriate control state.

[0122] <Application Example 1> The transmission 8 of the embodiment described above is provided with a plurality of transmission clutches 83. In this application example 1, by utilizing these transmission clutches 83, the racing phenomenon can be more effectively suppressed and the load on the transmission clutches 83 can be reduced.

[0123] That is, when the rotation speed of the drive motor 3 increases significantly, the slip of the transmission clutch 83 also increases accordingly. When the slip increases, the amount of heat generated by friction also increases, and the amount of wear of the transmission clutch 83 also increases. Therefore, the durability of the transmission clutch 83 decreases, and in some cases, the transmission clutch 83 may be damaged.

[0124] Therefore, in this application example 1, when the transmission clutch 83 is slipping due to magnetization control, the gear ratio of the transmission 8 is changed according to the state of the transmission clutch 83. By doing so, the slippage of the transmission clutch 83 is reduced, and the load on the transmission clutch 83 is reduced.

[0125] An example of the control flow is shown in Fig. 13. As described above, when the magnetization control is executed (step S50), the transmission clutch 83 slips, and a difference in rotation speed occurs between the input side 83a and the output side 83b (step S51). Then, due to the occurrence of the revving phenomenon, the difference in the rotation speed, that is, the differential rotation speed, increases rapidly.

[0126] The TCU 22 compares the differential rotation speed with a predetermined first determination value Δr1, and if it determines that the differential rotation speed is greater than the first determination value Δr1 (Yes in step S52), it switches the gear ratio of the transmission 8 so that the differential rotation speed becomes smaller (step S53). Note that basic controls such as target torque control and target power control are similar to those in the above-mentioned embodiment, and therefore description thereof will be omitted.

[0127] An example of the change of the gear ratio of the transmission 8 is shown in the upper diagram of FIG. 14. The upper diagram of FIG. 14 is a diagram for explaining the rotational states of the input shaft 80, the output shaft 81, and the transmission clutch 83 in the transmission 8, and the use state of the transmission clutch 83. The shaft J1 corresponds to the input shaft 80 of the transmission 8, the shaft J2 corresponds to the output shaft 81 of the transmission 8, and the shafts C1 and C2 correspond to the transmission clutch 83. The points 1 to 6 on the shaft J2 represent gear stages such as 1st gear and 2nd gear. For convenience, the upper diagram of FIG. 14 represents the multiple transmission clutches 83 as two transmission clutches C1 and C2 consisting of first and second gears.

[0128] A straight line L1 represents the state of first gear. In first gear, the first transmission clutch C1 is engaged (connected). A straight line L2 represents the state of second gear. In second gear, the second transmission clutch C2 is engaged. Here, a case will be described in which magnetization control is executed when the automobile 1 is running in second gear.

[0129] When the automobile 1 is running in second gear, if the second clutch control is changed to and magnetization control is executed, the motor speed Rm increases (see the arrow on the axis J1), and the line L2 changes to the line L2'. As a result, the slip in the second transmission clutch C2 that was being used becomes large, as shown by ΔR2.

[0130] In the state of the straight line L2', if there is a slip in the first transmission clutch C1, the magnitude of the slip is ΔR1. Therefore, in this case, the slip can be reduced by switching the second transmission clutch C2 to the first transmission clutch C1.

[0131] Therefore, in this application example 1, a predetermined first determination value Δr1 is preset in the TCU 22. When the TCU 22 determines that the differential rotation speed (ΔR2 in FIG. 14) of the slipping transmission clutch 83 is larger than the first determination value Δr1, the TCU 22 switches the gear ratio of the transmission 8 so that the differential rotation speed becomes smaller.

[0132] Specifically, as shown in the lower diagram of FIG. 14, in the process in which the motor rotation speed Rm decreases, there is a timing when the differential rotation speed becomes zero in the first transmission clutch C1. At that timing, the TCU 22 switches the transmission clutch 83 to be used from the second transmission clutch C2 to the first transmission clutch C1. By doing so, it is possible to reduce slippage and suppress damage to the second transmission clutch C2. Such a change in the gear ratio can be similarly performed in the transmission clutches 83 other than the first transmission clutch C1 and the second transmission clutch C2.

[0133] Thereafter, at an appropriate timing after the racing phenomenon is eliminated, the normal switching operation of the transmission clutch 83 is performed to switch to the transmission clutch 83 before switching. This will restore the initial state. Note that the decision as to whether or not to switch the gear ratio of the transmission 8 may be made based on the state of occurrence of the racing phenomenon after the start of the magnetizing control and the occurrence of the racing phenomenon, or may be made before the start of the magnetizing control by estimating the state of occurrence of the racing phenomenon.

[0134] <Application Example 2> In Application Example 1, the gear ratio of the transmission 8 is changed when there is a large slippage of the transmission clutch 83. In contrast, in Application Example 2, the gear ratio of the transmission 8 is changed when the temperature of the transmission clutch 83 is high.

[0135] If the temperature of the transmission clutch 83 becomes excessively high and this state continues for a long time, the durability of the transmission clutch 83 decreases and, in some cases, there is a risk of damage to the transmission clutch 83. Therefore, in Application Example 2, the temperature of the slipping transmission clutch 83 is compared with a second determination value, and when it is determined that the temperature of the transmission clutch 83 is higher than the second determination value, the gear ratio of the transmission 8 is switched so that the clutch is changed.

[0136] An example of the control flow is shown in Figure 15. Application example 2 is different from application example 1 in the criteria for switching the gear ratio of the transmission 8. Other than that, it is the same as application example 1, so the same reference numerals are used and the description is omitted.

[0137] In the application example 2, a predetermined second judgment value T1 is set in advance in the TCU 22. Then, the TCU 22 actually measures or estimates the temperature of the slipping transmission clutch 83, and when it is judged that the temperature of the slipping transmission clutch 83 is higher than the second judgment value T1, it switches the gear ratio of the transmission 8 so that a different transmission clutch 83 slips (step S60). By doing so, the transmission clutch 83 with a high temperature does not slip, and therefore the damage caused by the transmission clutch 83 can be suppressed.

[0138] Then, at an appropriate timing after the racing phenomenon is eliminated, the transmission clutch 83 can be switched to the pre-switched transmission clutch 83 by a normal switching operation of the transmission clutch 83. This will restore the initial state. Note that the decision as to whether or not to switch the gear ratio of the transmission 8 may be made based on the state of the racing phenomenon after the start of the magnetizing control, or may be made before the start of the magnetizing control by estimating the state of the racing phenomenon.

[0139] In Application Example 2, the transmission clutch 83 to be switched to may be a transmission clutch 83 whose temperature is not high. However, as in Application Example 1, it is preferable to switch the gear ratio of the transmission 8 so that the differential rotation speed becomes small. In this way, damage to the transmission clutch 83 to be switched to can be suppressed.

[0140] The disclosed technology is not limited to the above-described embodiment, and includes various other configurations. For example, in the above-described embodiment, the case where the transmission clutch 83 slips has been described. However, it is also possible to cause the second relay clutch 7 to slip instead of the transmission clutch 83.

[0141] Furthermore, there are many different configurations for the drive motor 3, transmission 8, etc. Therefore, these configurations can be selected according to the specifications, and the technology disclosed can be applied according to the specifications. For example, if there is one clutch, the technology shown in Application Example 2 cannot be applied. However, if there are multiple gear stages that can be changed even with one clutch, the gear ratio can be changed. Therefore, even in this case, the technology shown in Application Example 1 can be applied. [Explanation of symbols]

[0142] 1. Automobiles (electric vehicles) 2 Engine 3 Drive motor 4R Drive Wheel 5 First clutch 7 Second clutch 8. Transmission 10 Battery 20 Engine Control Unit (ECU) 21 Motor control unit (MCU) 21a Motor output control section 21b Magnetization control section 22 Transmission Control Unit (TCU) 22a Intermediate clutch control section 22b Transmission clutch control unit 23 Brake Control Unit (BCU) 24 General Control Unit (GCU) 33 Rotor 34 Stator 35 Magnet (variable magnetic force magnet) 80 Input shaft 81 Output shaft 82 Planetary Gear Mechanism 83 Transmission clutch 83a Input side 83b Output side

Claims

1. A control device for an electric vehicle capable of running using electric power, the control device including a drive motor having a rotor whose magnetic poles are formed by a variable magnetic force magnet whose magnetic force can be changed, and a clutch disposed between the drive motor and a drive wheel, During traveling of the electric vehicle, a target torque control is executed to control a motor torque output by the drive motor so that the motor torque matches a required torque required to be output to the drive wheels. a control device which, when executing magnetization control for changing the magnetic force of the magnetic force-variable magnet in a magnetization direction while the electric vehicle is traveling, executes the magnetization control after changing from first clutch control, which controls the engagement torque of the clutch to be higher than the required torque, to second clutch control, which causes the engagement torque to match the required torque, and which executes the magnetization control instead of the target torque control after the magnetization control, and which controls the motor torque so that the power output from the drive wheels matches a predetermined target power value.

2. 2. The control device according to claim 1, a control device that starts a feedback control for matching the rotation speeds of an input side and an output side of the clutch based on the rotation speed of the input side and the rotation speed of the output side of the clutch while the target power control is being executed.

3. 3. The control device according to claim 1, The clutch is a clutch of a transmission, and a control device switches the gear ratio of the transmission when the clutch is slipping by the magnetizing control executed after the second clutch control is changed, in response to a state of the clutch.

4. 4. The control device according to claim 3, A control device that compares a differential rotation speed, which is the difference between the rotation speed of the input side and the rotation speed of the output side of the slipping clutch, with a first judgment value, and when it is determined that the differential rotation speed is greater than the first judgment value, switches the gear ratio of the transmission so that the differential rotation speed becomes smaller.

5. The control device according to claim 3 or 4, The transmission includes a plurality of the clutches, A control device that compares the temperature of the slipping clutch with a second determination value, and when it is determined that the temperature of the clutch is higher than the second determination value, switches the gear ratio of the transmission so that the clutch is changed.

Images