Electric vehicle

Abstract

An electric vehicle includes an electric motor, a battery, an inverter, and a control device. The converter is provided between the battery and the motor, and converts DC power from the battery into AC power. AC power is supplied to the motor. The control device is capable of executing a specific operation in a state in which the electric vehicle is stopped. The determining action includes: determining a target electrical angle according to an initial value of the electrical angle of the motor; a control unit that controls the operation of the inverter to start energizing the motor at a predetermined rated current; determining a generation torque generated in the electric motor based on the rated current and the current value of the electrical angle; a feedback torque for damping is determined on the basis of the deviation of the current value with respect to the target electrical angle; and controlling an energizing current to the motor based on the generated torque, the feedback torque, and the rated current.

Description

Technical Field

[0001] The technology disclosed in this specification relates to an electric vehicle. Background Art

[0002] Japanese Patent Application Laid-Open No. 2022-182013 discloses an electric vehicle having an electric motor for driving wheels of the electric vehicle, a battery for supplying power to the electric motor, a converter, and a control device for controlling the operation of the converter. The converter is provided between the battery and the electric motor, and converts the DC power from the battery into AC power. The AC power is supplied to the electric motor.

[0003] In an electric vehicle, the motor is sometimes energized while the electric vehicle is parked. When the motor is energized, a torque corresponding to the electrical angle of the motor is generated. In addition, there is an electrical angle at which no torque is generated even if the motor is energized. If a torque is generated in the motor, the electrical angle of the motor varies approximately around the electrical angle at which no torque is generated. In response, the torque generated in the motor varies, and the electric vehicle vibrates. In the electric vehicle disclosed in Japanese Patent Publication No. 2022-182013, vibration of the parked electric vehicle is suppressed by adjusting the electrical angle of the electric vehicle when it is parked. Summary of the invention

[0004] In this specification, a new technique for suppressing vibrations generated by an electric vehicle while it is parked is provided.

[0005] In a first aspect disclosed in this specification, an electric vehicle includes:

[0006] an electric motor to drive wheels of the electric vehicle;

[0007] a battery for supplying electric power to the electric motor;

[0008] an inverter provided between the battery and the motor, and converting DC power from the battery into AC power supplied to the motor; and

[0009] a control device that controls the operation of the converter,

[0010] The control device is capable of executing a specific action accompanied by energizing the electric motor in a state where the electric vehicle is parked.

[0011] The specific actions include:

[0012] determining a target electrical angle relative to the electrical angle based on an initial value of the electrical angle of the motor;

[0013] controlling the operation of the inverter to start energizing the motor with a specified rated current;

[0014] determining a generated torque generated at the motor based on the rated current and the current value of the electrical angle;

[0015] determining a feedback torque for vibration reduction based on a deviation of the current value from the target electrical angle; and

[0016] The current supplied to the electric motor is controlled based on the generated torque, the feedback torque, and the rated current.

[0017] According to the above structure, the control device controls the current supplied to the motor based on the generated torque, the feedback torque and the rated current. In this case, the electrical angle of the motor can be made close to the target electrical angle. In addition, the target electrical angle is set to an electrical angle at which the generated torque is substantially zero when the motor is energized. Thus, the generated torque can be reduced. The generated torque variation can be suppressed. Therefore, the vibration generated by the electric vehicle during parking can be suppressed.

[0018] In a second aspect, in the first aspect, when controlling the energizing current, the control device may determine the target value of the energizing current based on a ratio obtained by dividing a sum of the generated torque and the feedback torque by the generated torque.

[0019] The torque generated is proportional to the current. Therefore, by adjusting the current, the torque generated can be adjusted. By adjusting the torque generated, the electrical angle of the motor can be brought closer to the target electrical angle earlier. Therefore, the vibration generated by the parked electric vehicle can be suppressed earlier.

[0020] In a third aspect, another electric vehicle includes:

[0021] an electric motor to drive wheels of the electric vehicle;

[0022] a battery for supplying electric power to the electric motor;

[0023] an inverter provided between the battery and the motor, and converting DC power from the battery into AC power supplied to the motor; and

[0024] a control device for controlling the operation of the converter,

[0025] The control device is capable of executing a specific action accompanied by energizing the electric motor in a state where the electric vehicle is parked.

[0026] The specific actions include:

[0027] controlling the operation of the inverter to start energizing the motor with a specified rated current;

[0028] determining a generated torque generated at the motor based on the rated current and a current value of the electrical angle of the motor;

[0029] determining a feedback torque for vibration reduction based on the angular velocity of the electrical angle; and

[0030] The current supplied to the electric motor is controlled based on the generated torque, the feedback torque, and the rated current.

[0031] According to the above structure, the control device controls the current supplied to the motor based on the generated torque, the feedback torque and the rated current. In this case, the electrical angle of the motor can be made close to the electrical angle at which the generated torque is substantially zero when the motor is energized. Thus, the generated torque can be reduced and the generated torque variation can be suppressed. Therefore, the vibration generated by the electric vehicle during parking can be suppressed.

[0032] In a fourth aspect, in the third aspect, when controlling the energizing current, the control device determines the target value of the energizing current based on a ratio obtained by dividing a sum of the generated torque and the feedback torque by the generated torque.

[0033] The torque generated is proportional to the current. Therefore, by adjusting the current, the torque generated can be adjusted. By adjusting the torque generated, the electrical angle of the motor can be brought closer to the target electrical angle earlier. Therefore, the vibration generated by the parked electric vehicle can be suppressed earlier.

[0034] In a fifth embodiment, in any one of the first to fourth embodiments, the specific action may be a battery heating action for the purpose of heating the battery, or a neutral point charging action for connecting an external power supply to the neutral point of the motor and charging the battery.

[0035] According to the above configuration, it is possible to suppress the occurrence of vibration in the electric vehicle when the battery temperature raising operation or the neutral point charging operation is performed. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like symbols represent like elements, and wherein:

[0037] Figure 1 A circuit diagram of the charging system 2 is shown.

[0038] Figure 2 An example of the torque map 64 is shown.

[0039] Figure 3A flowchart showing the energization current control process of the first embodiment.

[0040] Figure 4 FIG. 1 shows the change in the electrical angle when the neutral point charging operation is performed in the electric vehicle of the comparative example.

[0041] Figure 5 FIG. 1 shows the transition of the electrical angle when the neutral point charging operation is performed in the electric vehicle 10 according to the first embodiment.

[0042] Figure 6 A flowchart showing the energization current control process of the second embodiment. DETAILED DESCRIPTION

[0043] First embodiment

[0044] like Figure 1 As shown, the charging system 2 includes an electric vehicle 10 and a charging device 100. The electric vehicle 10 includes a battery 12, a system main relay 14, a running smoothing capacitor 16, an inverter 20, a motor 30, a charging circuit 40, a charging interface 50, and a control device 60. The charging interface 50 is detachably connected to the charging device 100 and receives charging power for charging the battery 12.

[0045] The battery 12 has a plurality of secondary battery cells (not shown) such as lithium-ion battery cells built therein, and is a rechargeable secondary battery configured to be repeatedly charged and discharged, and is typically a lithium-ion battery. The battery 12 is connected to the converter 20 via a system main relay 14. The operation of the system main relay 14 is controlled by the control device 60. The running smoothing capacitor 16 is provided between the battery 12 and the converter 20.

[0046] The inverter 20 is provided between the running smoothing capacitor 16 and the motor 30. The inverter 20 is a device that converts the DC power from the battery 12 into AC power. The inverter 20 includes three upper switching elements 22UH, 22VH, and 22WH and three lower switching elements 22UL, 22VL, and 22WL. Hereinafter, "switching element" is referred to as "SW element". The upper SW elements 22UH, 22VH, and 22WH are connected in series with the lower SW elements 22UL, 22VL, and 22WL, respectively.

[0047] The midpoint between the upper SW element 22UH and the lower SW element 22UL connected in series is electrically connected to the U-phase terminal 32 of the motor 30. Thus, the upper SW element 22UH and the lower SW element 22UL constitute a pair of upper and lower U-phase arms that connect the U-phase terminal 32 of the motor 30 to the positive or negative pole of the battery 12. Similarly, the upper SW element 22VH and the lower SW element 22VL connected in series constitute a pair of upper and lower V-phase arms, and the midpoint between them is electrically connected to the V-phase terminal 34 of the motor 30. In addition, the upper SW element 22WH and the lower SW element 22WL connected in series constitute a pair of upper and lower W-phase arms, and the midpoint between them is electrically connected to the W-phase terminal 36 of the motor 30. The operation of the three lower SW elements 22UL, 22VL, and 22WL, and the operation of the three lower SW elements 22UL, 22VL, and 22WL are controlled by the control device 60.

[0048] The motor 30 is a three-phase AC motor that drives the front wheels of the electric vehicle 10 using the power supplied from the battery 12. The motor 30 includes a U-phase coil 32A, a V-phase coil 34A, and a W-phase coil 36A. One end of each of the U-phase coil 32A, the V-phase coil 34A, and the W-phase coil 36A is connected to the U-phase terminal 32, the V-phase terminal 34, and the W-phase terminal 36, respectively. The other ends of each of the U-phase coil 32A, the V-phase coil 34A, and the W-phase coil 36A are connected to each other at a neutral point 30A. The motor 30 also includes an electrical angle sensor 38 that detects the electrical angle of a rotor (not shown) of the motor 30.

[0049] The charging circuit 40 is a circuit for supplying power from the charging device 100 to the storage battery 12. The charging circuit 40 includes a first charging relay 42, a charging smoothing capacitor 44, and a second charging relay 46. The charging smoothing capacitor 44 is provided between the motor 30 and the charging interface 50. The first charging relay 42 is provided between the neutral point 30A of the motor 30 and the first charging relay 42. The second charging relay 46 is provided between the charging interface 50 and the charging smoothing capacitor 44. The operations of the first charging relay 42 and the second charging relay 46 are controlled by the controller 60.

[0050] The control device 60 is a computer including a CPU. The control device 60 controls the operation of each component of the electric vehicle 10. The control device 60 includes a memory 62 for storing a torque map 64. Figure 2 As shown, the torque map 64 is information indicating the relationship between the electrical angle [°] of the motor 30 and the generated torque [Nm]. The generated torque is the torque generated by the motor 30 when the motor 30 is energized. The torque map 64 is used in the energizing current control process ( Figure 3The magnitude of the generated torque is proportional to the current value supplied to the motor 30. The torque map 64 is information corresponding to the rated current Ir of the motor 30 in the neutral point charging operation described later.

[0051] Figure 1 The control device 60 is configured to be able to perform a neutral point charging operation accompanied by energizing the motor 30 when the electric vehicle 10 is parked. The neutral point charging operation is an operation for charging the battery 12 by boosting the voltage of the charging power received from the charging device 100. When the charging device 100 is connected to the charging interface 50 and the voltage of the charging power received from the charging device 100 (for example, 400 V) is lower than the rated voltage of the battery 12 (for example, 800 V), the control device 60 performs the neutral point charging operation.

[0052] The following is an overview of the neutral point charging operation. Figure 1 As shown, the control device 60 electrically connects the system main relay 14, the first charging relay 42, and the second charging relay 46. In addition, the control device 60 performs a step-up operation to charge the battery 12. Specifically, the control device 60 repeatedly turns on and off at least one of the lower SW elements 22UL, VL, and WL while maintaining the upper SW elements 22UH, 22VH, and 22WH in an off state. The control device 60 controls the duty ratio of the lower SW element that is turned on and off. In addition, the control device 60 can also symmetrically turn on and off the upper SW elements 22UH, 22VH, and 22WH in synchronization with the lower SW elements 22UL, VL, and WL that are repeatedly turned on and off. For example, the case of turning on and off the lower SW element 22UL is described. When the lower SW element 22UL is turned on, current flows through the U-phase coil 32A and the lower SW element 22UL. Energy is stored in the U-phase coil 32A. When lower SW element 22UL is turned off in this state, the energy stored in U-phase coil 32A is superimposed on the power from charger 100. As a result, the voltage of the power supplied from inverter 20 to battery 12 is increased. As a result, battery 12 is charged.

[0053] Power-on current control processing; Figure 3

[0054] Reference Figure 3 , the current control process performed in the neutral point charging operation is described. The current control process is a process for controlling the current I supplied to the motor 30 in the neutral point charging operation. The control device 60 starts the neutral point charging operation at the same time. Figure 3 processing.

[0055] In S10 , the control device 60 determines the electrical angle of the motor 30 at the start time of the neutral point charging operation (hereinafter referred to as “initial electrical angle φs”). The initial electrical angle is an initial value of the electrical angle of the motor 30 .

[0056] In S12, the control device 60 determines the target electrical angle φt using the torque map 64 stored in the memory 62 and the initial electrical angle φs determined in S10. The control device 60 determines the target electrical angle φt as the electrical angle closest to the initial electrical angle φs among the multiple electrical angles at which the generated torque is zero. For example, when the initial electrical angle φs is 110°, 120° is determined as the target electrical angle φt. In addition, in a modified example, the target electrical angle φt may also be an electrical angle at which the generated torque becomes less than a specified torque when the motor 30 is energized.

[0057] In S14, control device 60 controls the operation of inverter 20 and starts energizing motor 30. Control device 60 determines rated current Ir as target value It of energizing current I, and controls the operation of inverter 20 so as to achieve target value It.

[0058] In S20 , control device 60 determines the current electrical angle φp of motor 30 .

[0059] In S22, the control device 60 determines whether the state in which the absolute value of the electrical angle difference obtained by subtracting the current electrical angle φp from the target electrical angle φt is less than the first specified value Va continues for more than the first specified time. The first specified value Va is a positive value. If the state in which the absolute value of the electrical angle difference is less than the first specified value Va continues for more than the first specified time (yes in S22), the control device 60 ends Figure 3 In addition, the control device 60 completes Figure 3 After the processing, the rated current Ir is set as the target value It, and the neutral point charging operation is continued. On the other hand, if the state where the absolute value of the electrical angle difference is less than the first predetermined value Va does not continue for more than the first predetermined time (No in S22), the control device 60 enters S30.

[0060] In S30, the control device 60 determines the feedback torque Tf using the target electrical angle φt and the current electrical angle φp. The feedback torque is hereinafter referred to as "FB torque". The FB torque Tf is a torque used to damp vibrations generated by the electric vehicle 10 when the vehicle is parked. The control device 60 determines the FB torque Tf by multiplying the value obtained by subtracting the target electrical angle φt from the current electrical angle φp by a second predetermined value Vb. The second predetermined value Vb is a negative value.

[0061] In S32 , the control device 60 determines the generated torque Tc using the rated current Ir, the torque map 64 , and the current electrical angle φp.

[0062] In S34, the control device 60 calculates the output torque To. The control device 60 calculates the output torque To by adding the generated torque Tc to the FB torque Tf.

[0063] In S36, the control device 60 calculates the torque ratio R, which is a ratio obtained by dividing the output torque To by the generated torque Tc. That is, the torque ratio R is a ratio obtained by dividing the sum of the generated torque Tc and the FB torque Tf by the generated torque Tc.

[0064] In S40, the control device 60 determines whether the torque ratio R exceeds "1". When the torque ratio R exceeds "1" (Yes in S40), the control device 60 proceeds to S42. On the other hand, when the torque ratio R is less than "1" (No in S40), the control device 60 proceeds to S44.

[0065] In S42, the control device 60 determines the rated current Ir as the target value It. When S42 is completed, the control device 60 proceeds to S50.

[0066] In addition, in S44, the control device 60 determines whether the torque ratio R exceeds "0 (zero)". When the torque ratio R exceeds "0" (Yes in S44), the control device 60 proceeds to S46. On the other hand, when the torque ratio R is less than "0" (No in S44), the control device 60 proceeds to S48.

[0067] In S46 , the control device 60 determines the value (R*Ir) obtained by multiplying the rated current Ir by the torque ratio R as the target value It. The target value It in this case is a value equal to or less than the rated current Ir. When S46 is completed, the control device 60 proceeds to S50 .

[0068] In S48, the control device 60 determines the current value "0 (zero)" as the target value It. When S48 is completed, the control device 60 proceeds to S50.

[0069] In S50, the control device 60 controls the energized current I so as to reach the determined target value It. When S50 is completed, the control device 60 returns to S20.

[0070] As described above, the control device 60 executes the processes of S30 to S50 until a YES determination is made in S22 .

[0071] Reference Figure 4 , Figure 5 , for current control processing (refer to Figure 3 ) is explained. Figure 4 , Figure 5 The vertical axis of the timing diagram represents the electrical angle of the motor 30. Figure 4 , Figure 5 In the initial state, the electrical angle of the motor 30 of the stopped electric vehicle 10 is 117°. Figure 4 FIG. 2 shows the change of the electrical angle in the electric vehicle of the comparative example. Figure 5 10 shows the change of the electrical angle in the electric vehicle 10 of the present embodiment. The electric vehicle of the comparative example does not perform the energizing current control process (see Figure 3 ) Other than this point, it has the same structure as the electric vehicle 10.

[0072] exist Figure 4 When the neutral point charging operation starts, the electric vehicle of the comparative example starts to energize the motor. Figure 2 As shown in , the torque Tc generated when the electrical angle of the motor is 117° is a positive value. Figure 4 As shown, when the power starts to be supplied to the motor, the motor generates a positive generated torque Tc, and the electrical angle of the motor increases. Furthermore, (1) if the electrical angle of the motor exceeds 120°, the motor generates a negative generated torque Tc. Therefore, the electrical angle of the motor decreases. Furthermore, (2) if the electrical angle of the motor is less than 120°, the motor generates a positive generated torque Tc, and the electrical angle of the motor increases. Thereafter, (1) and (2) are repeated. That is, the electrical angle of the motor fluctuates approximately around 120°. Accordingly, the motor generates torque fluctuations, and the electric vehicle of the comparative example vibrates. In addition, due to the torque fluctuations of the motor, a tooth rattling sound may also be generated in the drive system of the electric vehicle of the comparative example.

[0073] exist Figure 5 When the neutral point charging operation is started, the electric vehicle 10 determines the initial electrical angle φs (117°) ( Figure 3 In S10, 120° is determined as the target electrical angle φt (S12), and the electric motor 30 is energized (S14). Figure 4 Similarly, when the electric motor 30 is energized, a positive torque Tc is generated in the electric motor 30, and the electrical angle of the electric motor 30 increases. Figure 3), when the current electrical angle φp of the motor 30 is less than 120°, the FB torque Tf becomes a positive value (S30). Therefore, the torque ratio R is greater than 1 (Yes in S40), and the target value It becomes the rated current Ir (S42). In addition, when the current electrical angle φp is greater than 120°, the FB torque Tf becomes a negative value (S22). Therefore, the torque ratio R is less than 1 (No in S40, Yes in S44). In addition, in this case, the torque ratio R is greater than zero. Therefore, the target value It becomes "R*Ir" (S46). Therefore, when the current electrical angle φp is greater than 120°, the target value It is smaller than the rated current Ir. The absolute value of the generated torque Tc of the motor 30 is smaller than the absolute value of the generated torque Tc when the target value It is the rated current Ir. By reducing the absolute value of the generated torque Tc, the amplitude of the electrical angle becomes smaller than when the target value It is the rated current Ir. Furthermore, by reducing the amplitude of the electrical angle, the absolute value of the torque Tc generated when the electrical angle is less than 120° is also reduced. Thus, by reducing the amplitude of the electrical angle, the variation of the electrical angle of the motor 30 is suppressed, and the electrical angle is brought close to the target electrical angle φt. As a result, the vibration of the electric vehicle 10 is damped. In addition, the gear rattling sound of the drive system of the electric vehicle 10 is also suppressed.

[0074] As described above, the electric vehicle 10 includes the electric motor 30 that drives the front wheels (an example of “wheels”) of the electric vehicle 10, the battery 12 that supplies power to the electric motor 30, the inverter 20, and the control device 60 that controls the operation of the inverter 20. The inverter 20 is provided between the battery 12 and the electric motor 30, and converts the DC power from the battery 12 into AC power. The AC power is supplied to the electric motor 30. The control device 60 can perform a neutral point charging operation (an example of a “specific operation”) accompanied by energizing the electric motor 30 while the electric vehicle 10 is parked. The neutral point charging operation includes: a step of determining a target electrical angle φt based on an initial electrical angle φs (an example of an “initial value of the electrical angle of the electric motor”); Figure 2 The invention further comprises the following steps: a step of controlling the operation of the converter 20 to start energizing the motor 30 with a specified rated current Ir (S14); a step of determining a generated torque Tc generated in the motor 30 based on the rated current Ir and a current electrical angle φp (an example of a “current value of the electrical angle”) (S32); a step of determining a FB torque Tf based on a deviation of the current electrical angle φp from a target electrical angle φt (S30); and a step of controlling a energizing current I supplied to the motor 30 based on the generated torque Tc, the FB torque Tf and the rated current Ir (S30 to S50).

[0075] According to the above structure, the control device 60 controls the current I supplied to the motor 30 based on the generated torque Tc, the FB torque Tf, and the rated current Ir. In this case, the electrical angle of the motor 30 can be made close to the target electrical angle φt. As a result, the generated torque Tc can be reduced. The generated torque Tc can be suppressed from changing. Therefore, during the neutral point charging operation, the vibration generated by the parked electric vehicle 10 can be suppressed.

[0076] Furthermore, when controlling the energizing current I, the control device 60 determines the target value It of the energizing current I based on the torque ratio R which is a ratio obtained by dividing the sum of the generated torque Tc and the FB torque Tf by the generated torque Tc ( S40 to S48 ).

[0077] The generated torque Tc is proportional to the current I. Therefore, the magnitude of the generated torque Tc can be adjusted by adjusting the magnitude of the current I. By adjusting the magnitude of the generated torque Tc, the electrical angle of the motor 30 can be brought closer to the target electrical angle φt earlier. Therefore, the vibration generated by the parked electric vehicle 10 can be suppressed earlier.

[0078] Second embodiment

[0079] The electric vehicle 10 of the second embodiment replaces Figure 3 The current control process is performed by Figure 6 The energizing current control process is different in this respect.

[0080] Power-on current control processing; Figure 6

[0081] Reference Figure 6 , the current control process performed in the neutral point charging operation is described. S114 and Figure 3 Same as S14.

[0082] In S120 , control device 60 determines angular velocity ω of motor 30 .

[0083] In S122, the control device 60 determines whether the state in which the absolute value of the angular velocity ω is less than the third predetermined value Vc continues for more than the second predetermined time. The third predetermined value Vc is a positive value. If the state in which the absolute value of the angular velocity ω is less than the third predetermined value Vc continues for more than the second predetermined time (yes in S122), the control device 60 ends. Figure 6 In addition, the control device 60 ends Figure 6 After the processing, the rated current Ir is used as the target value It of the energizing current I, and the neutral point charging operation is continued. On the other hand, if the state where the absolute value of the angular velocity ω is less than the third specified value Vc does not continue for more than the second specified time (No in S122), the control device 60 enters S130.

[0084] In S130, the control device 60 determines the FB torque Tf using the angular velocity ω. The control device 60 determines the FB torque Tf by multiplying the angular velocity ω by a fourth predetermined value Vd. The fourth predetermined value Vd is a negative value.

[0085] S132 to S150 and Figure 3 The same as S32 to S50.

[0086] In the present embodiment, by determining the FB torque Tf using the angular velocity ω, it is possible to damp the vibration of the electric vehicle 10 during the neutral point charging operation.

[0087] As described above, the electric vehicle 10 includes the motor 30 for driving the front wheels of the electric vehicle 10, the battery 12 for supplying power to the motor 30, the inverter 20, and the control device 60 for controlling the operation of the inverter 20. The inverter 20 is provided between the battery 12 and the motor 30, and converts the DC power from the battery 12 into AC power. The AC power is supplied to the motor 30. The control device 60 can perform a neutral point charging operation accompanied by energizing the motor 30 while the electric vehicle 10 is parked. The neutral point charging operation controls the operation of the inverter 20, starts energizing the motor 30 with a predetermined rated current Ir (S114), determines the generated torque Tc generated in the motor 30 based on the rated current Ir and the current angular velocity ω of the motor 30 (S132), determines the FB torque Tf for vibration reduction based on the current angular velocity ω (S130), and controls the energizing current I to the motor 30 based on the generated torque Tc, the FB torque Tf, and the rated current Ir (S140 to S150).

[0088] According to the above structure, the control device 60 controls the current I supplied to the motor 30 based on the generated torque Tc, the FB torque Tf, and the rated current Ir. In this case, the electrical angle of the motor 30 can be made close to the electrical angle at which the generated torque is substantially zero when the motor 30 is energized. As a result, the generated torque Tc can be reduced, and the variation of the generated torque Tc can be suppressed. Therefore, the vibration generated by the electric vehicle 10 during parking can be suppressed.

[0089] When controlling the energizing current I, the control device 60 determines a target value It of the energizing current I based on a torque ratio R which is a ratio obtained by dividing the sum of the generated torque Tc and the FB torque Tf by the generated torque Tc.

[0090] The generated torque Tc is proportional to the current I. Therefore, the magnitude of the generated torque Tc can be adjusted by adjusting the magnitude of the current I. By adjusting the magnitude of the generated torque Tc, the electrical angle of the motor 30 can be brought closer to the target electrical angle φt earlier. Therefore, the vibration generated by the parked electric vehicle 10 can be suppressed earlier.

[0091] The above detailed description of the specific examples of the technology disclosed in this specification is only for illustration and does not limit the scope of protection claimed. The technology described in the scope of protection claimed includes various modifications and changes to the specific examples illustrated above. The following lists the modified examples of the above embodiment.

[0092] The control device 60 may also be capable of performing a battery heating operation for the purpose of heating the battery 12 while the electric vehicle 10 is parked. For example, in the battery heating operation, the control device 60 controls the operation of the inverter 20 and the motor 30 to overheat the coolant of the drive system of the electric vehicle 10. Then, the temperature of the battery 12 is raised using the heated coolant. In this modified example, the control device 60 performs the battery heating operation. Figure 3 or Figure 6 According to such a configuration, vibration of the electric vehicle 10 during the battery temperature raising operation can be suppressed.

[0093] The technical elements described in this specification or drawings are technically useful alone or in various combinations, and are not limited to the combinations recorded in the scope of protection claimed at the time of application. In addition, the technology illustrated in this specification or drawings can achieve multiple purposes at the same time. Achieving one of the purposes is technically useful.

Claims

1. An electric vehicle comprising: an electric motor to drive wheels of the electric vehicle; a battery for supplying electric power to the electric motor; a converter, disposed between the battery and the motor, for converting DC power from the battery into AC power supplied to the motor; as well as a control device for controlling the operation of the converter, The control device is capable of executing a specific action accompanied by energizing the electric motor in a state where the electric vehicle is parked. The specific actions include: determining a target electrical angle relative to the electrical angle based on an initial value of the electrical angle of the motor; controlling the operation of the inverter to start energizing the motor with a specified rated current; determining a generated torque generated at the motor based on the rated current and the current value of the electrical angle; determining a feedback torque for vibration reduction based on a deviation of the current value from the target electrical angle; and Based on the generated torque, the feedback torque, and the rated current, a current supplied to the electric motor is controlled.

2. The electric vehicle according to claim 1, wherein: The control device determines a target value of the energizing current based on a ratio obtained by dividing a sum of the generated torque and the feedback torque by the generated torque when controlling the energizing current.

3. An electric vehicle comprising: an electric motor to drive wheels of the electric vehicle; a battery for supplying electric power to the electric motor; a converter, disposed between the battery and the motor, for converting DC power from the battery into AC power supplied to the motor; as well as a control device for controlling the operation of the converter, The control device is capable of executing a specific action accompanied by energizing the electric motor in a state where the electric vehicle is parked. The specific actions include: controlling the operation of the inverter to start energizing the motor with a specified rated current; determining a generated torque generated at the motor based on the rated current and a current value of the electrical angle of the motor; determining a feedback torque for vibration reduction based on the angular velocity of the electrical angle; and The current supplied to the electric motor is controlled based on the generated torque, the feedback torque, and the rated current.

4. The electric vehicle according to claim 3, wherein: The control device determines a target value of the energizing current based on a ratio obtained by dividing a sum of the generated torque and the feedback torque by the generated torque when controlling the energizing current.

5. The electric vehicle according to any one of claims 1 to 4, wherein: The specific operation is a battery temperature increasing operation for increasing the temperature of the battery, or a neutral point charging operation for connecting an external power source to the neutral point of the electric motor to charge the battery.

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