vehicle

Abstract

To provide a vehicle capable of suppressing increase of vehicle behaviors in a situation where torque is generated on a motor during charging.SOLUTION: An electric vehicle 100 includes: a battery 2; a 3-phase motor 3; an inverter 5; a charge terminal 131P to be connected to the battery 2 and also to any one phase of coils 32U of the 3-phase motor 3 when the battery 2 is charged; auxiliary equipment 4 driven by 800 V of voltage of the battery 2 when the battery 2 is discharging and driven by 800 V of voltage boosted by the 3-phase motor 3 and the inverter 5 when the battery 2 is charged by 400 V of voltage; a controller 10 that controls the charge of the battery 2; and an EPB7 that restricts rotation of a wheel W. The controller 10 detects engagement of charge plugs to charge terminals 131P, 131N, and also activates the EPB7 when detecting that a charge voltage of the battery 2 is 400 V.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to a vehicle equipped with a battery. [Background technology]

[0002] In recent years, research and development has been conducted into charging mobility vehicles equipped with secondary batteries that contribute to energy efficiency, in order to ensure that more people have access to affordable, reliable, sustainable, and advanced energy.

[0003] Regarding charging and power supply for mobility vehicles equipped with secondary batteries, there are two types of charging equipment, such as charging stations: 400V class with an upper voltage limit of 500V, and 800V class with an upper voltage limit of 1000V. If a mobility vehicle is only compatible with 400V class charging equipment or 800V class charging equipment, it will not be able to enjoy the benefits of rapid charging.

[0004] Therefore, for example, Patent Document 1 describes a method of switching between a series charging mode in which two batteries are connected in series, a parallel charging mode in which two batteries are connected in parallel, and a single charging mode in which one of the two batteries is charged, to match the charging voltage of the charging equipment.

[0005] Patent document 1 also mentions that because the motor is located on the power transmission path of the two batteries, when charging, the charging current flows through the motor coil, generating torque and causing the motor to rotate.

[0006] In response to this, Patent Document 1 describes that charging begins after the motor rotor is moved to a zero torque position after the vehicle has stopped, but when moving the motor rotor after the vehicle has stopped, it is necessary to release the parking brake once. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 7244075 Summary of the Invention [Problem to be solved by the invention]

[0008] However, releasing the parking brake to move the vehicle is not desirable because it is not the user's intention. Also, there may be situations where the vehicle cannot be moved due to obstacles or the like.

[0009] The present invention provides a vehicle that can suppress abrupt changes in vehicle behavior when torque is generated in the motor during charging. [Means for solving the problem]

[0010] The present invention provides A battery, a motor that drives the wheels; an inverter that converts DC power from the battery into AC power and supplies the AC power to the motor; a charging terminal connected to the battery when charging the battery and connected to a coil of any one phase of the motor; an electric device that is driven by a first voltage from the battery when the battery is being discharged, and that is driven by the first voltage boosted by the motor and the inverter when the battery is being charged by a second voltage lower than the first voltage; a control unit that controls charging of the battery; A vehicle equipped with a brake mechanism that restricts rotation of the wheel, The control unit When it is detected that the charging plug is fitted into the charging terminal and when it is detected that the charging voltage of the battery is the second voltage, the brake mechanism is activated. [Effects of the Invention]

[0011] According to the present invention, it is possible to suppress the vehicle behavior from becoming abrupt in a situation where torque is generated in the motor during charging. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing the configuration of a charging system 1 mounted on an electric vehicle 100 according to one embodiment of the present invention. [Figure 2] FIG. 10 is a diagram showing a first voltage state of the battery 2 (started at 800 V). [Figure 3] FIG. 10 is a diagram showing a second voltage state of the battery 2 (started at 400 V). [Figure 4] 3 is a diagram showing the flow of current when the electric vehicle 100 is running. FIG. [Figure 5] 10 is a diagram showing the flow of current when the electric vehicle 100 is charged at a first voltage (800 V). FIG. [Figure 6] 10 is a diagram showing the flow of current when the electric vehicle 100 is charged at a second voltage (400 V). FIG. [Figure 7] 1 is a schematic diagram showing a schematic configuration of a charging system 1. FIG. [Figure 8] 10 is a diagram showing the current flow during two-phase boosting during charging at a second voltage (400V) in the charging system 1. FIG. [Figure 9] 10 is a diagram showing a current flow during one-phase boosting during charging at a second voltage (400 V) in the charging system 1. FIG. [Figure 10] 10 is a graph showing the currents flowing through coils 32U, 32V, and 32W when electric vehicle 100 is running. [Figure 11] 10A to 10D show the positional relationship between the stator 35 and the rotor 37 (permanent magnet 36) of the three-phase motor 3. FIG. [Figure 12] 10 is a flowchart of charge start control during second voltage (400V) charging. [Figure 13] 10 is a graph showing the relationship between the rate of change of current (di / dt) and acceleration (G) during charging at a second voltage (400 V). [Figure 14] 1 is a side view illustrating an outline of an electric vehicle 100 according to one embodiment of the present invention. [Figure 15] 2 is a diagram illustrating a parking mechanism of the electric vehicle 100. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] An electric vehicle 100 according to one embodiment of the present invention will now be described with reference to the drawings.

[0014] As shown in Fig. 14, the electric vehicle 100 is an electric vehicle, hybrid vehicle, fuel cell vehicle or the like equipped with a charging system 1 (see Fig. 1), and can travel by driving a three-phase motor 3 with power supplied from a battery 2. The electric vehicle 100 is provided with wheel brakes 6, an EPB (Electric Parking Brake) 7 that restricts the rotation of the rear wheels, and a parking mechanism 8 that restricts the rotation of the front wheels.

[0015] The wheel brake 6 is, for example, a hydraulic brake, and applies a braking force to the wheel W in response to the operation of the brake pedal by the user.

[0016] The parking mechanism 8 is activated when the shift is in the parking range. When the parking mechanism 8 is activated, as shown in (A) of Figure 15, the claw portion 82 of the parking pole 81 engages with the recessed portion 84 of the parking gear 83, restricting the rotation of the parking gear 83, and accordingly restricting the rotation of the wheels W (front wheels).

[0017] The EPB 7 is controlled to be in an activated state or an inactivated state in response to a user operation, and therefore, even when the electric vehicle 100 is parked, the EPB 7 may be in both an activated state and an inactivated state.

[0018] The charging system 1 is compatible with 400V and 800V class charging equipment, and can not only rapidly charge the battery 2 at charging voltages of 400V and 800V, but can also drive the three-phase motor 3 and auxiliary equipment 4 at a base voltage of 800V.

[0019] Specifically, as shown in FIG. 1, the charging system 1 includes a battery 2, a three-phase motor 3, an auxiliary device 4, an inverter 5 (PDU), power supply circuits 11P, 11N, auxiliary device drive circuits 12P, 12N, DC power supply circuits 13P, 13N, a branch circuit 14, and a control unit 10.

[0020] As shown in Figures 1 to 3, battery 2 includes first power storage unit 21, second power storage unit 22, first to fifth contactors M / C, S / C_A, S / C_B, S / C_C, P / C, first resistor R1, current sensor IS, and current breaker FUSE.

[0021] First power storage unit 21 and second power storage unit 22 are each a battery module capable of charging and discharging 400V.

[0022] The first contactor M / C is disposed at the end of the positive electrode side of the battery 2, and functions as a main switch that turns on / off the connection of the battery 2 with the outside (power supply circuit 11P).

[0023] The second to fourth contactors S / C_A, S / C_B, and S / C_C switch the connection state between the first power storage unit 21 and the second power storage unit 22. For example, as shown in FIG. 2, when the second contactor S / C_A is turned ON and the third contactor S / C_B and the fourth contactor S / C_C are turned OFF, the battery 2 enters a first voltage state (800 V start) in which the first power storage unit 21 and the second power storage unit 22 are connected in series, and charging and discharging at 800 V becomes possible. Also, as shown in FIG. 3, when the second contactor S / C_A is turned OFF and the third contactor S / C_B and the fourth contactor S / C_C are turned ON, the battery 2 enters a second voltage state (400 V start) in which the first power storage unit 21 and the second power storage unit 22 are connected in parallel, and charging and discharging at 400 V becomes possible. The term "start" is a concept that includes driving the electric vehicle equipped with the charging system 1 while the vehicle is traveling, and charging the electric vehicle while the vehicle is stopped.

[0024] The fifth contactor P / C and the first resistor R1 are arranged in series and in parallel with the first contactor M / C. In the first voltage state and the second voltage state, the fifth contactor P / C is turned on before the first contactor M / C is turned on, thereby protecting the first contactor M / C from excessive inrush current.

[0025] Current sensor IS is arranged between first contactor M / C and power storage units 21 and 22 to measure the current.

[0026] The current breaker FUSE is disposed at the end of the negative electrode side of the battery 2, and cuts off the connection of the battery 2 to the outside (power supply circuit 11N) in the event of an abnormality. In the charging system 1 of this embodiment, the current breaker FUSE is configured with a pyro-fuse that can intentionally cut off current in response to an electrical signal, and in the event of an abnormality (such as a vehicle collision or a short circuit in the battery 2), the current breaker FUSE is cut off and all contactors in the battery 2 are turned OFF (open).

[0027] The three-phase motor 3 includes a stator 35 around which three-phase coils 32U, 32V, and 32W are wound, and a rotor 37 on which a permanent magnet 36 is disposed (see FIG. 11 ). One ends of the three-phase coils 32U, 32V, and 32W are connected at a neutral point 31, and the other ends are connected to the inverter 5 via a U-phase terminal 33U, a V-phase terminal 33V, and a W-phase terminal 33W. The other end of any one of the coils 32U, 32V, and 32W is connected to the branch circuit 14 at a connection 34. In this embodiment, of the three-phase coils 32U, 32V, and 32W, the U-phase coil 32U is connected to the branch circuit 14 at a connection 34 located between the U-phase terminal 33U and the inverter 5.

[0028] The inverter 5 converts the DC power supplied from the battery 2 into three-phase AC power by switching a plurality of switching elements, thereby rotating and driving the three-phase motor 3. Furthermore, as will be described in detail later, when a DC current (400 V) is supplied from the branch circuit 14 to the connection part 34, the inverter 5 can function as a boost circuit (DC voltage converter) that boosts the DC current by switching a plurality of switching elements using the coil connected to the branch circuit 14 and one or two other phase coils.

[0029] The accessories 4 are in-vehicle devices that can be driven by DC power from the battery 2 and an external power source, and include, for example, an electric compressor E-COMP for an air conditioner (A / C), an electric heater ECH, and an accessory converter DCDC. The electric compressor E-COMP and the electric heater ECH are high-voltage in-vehicle devices, and the accessory converter DCDC reduces the DC power from the battery 2 and the external power source to drive the low-voltage in-vehicle devices. The accessories 4 are connected to the battery 2 via accessory drive circuits 12P and 12N, a sixth contactor VS / C, and power supply circuits 11P and 11N. In this embodiment, the accessories 4 operate at a base voltage of 800 V while the vehicle is running. However, the accessories 4 can operate at voltages other than 800 V, and are configured to operate at a more efficient drive voltage when charging at 400 V, as described below.

[0030] The power supply circuits 11P, 11N are configured as a pair of positive and negative circuits and connect the battery 2 and the inverter 5 (three-phase motor 3). The power supply circuits 11P, 11N are provided with connection parts 111P, 111N with the DC power supply circuits 13P, 13N, and connection parts 112P, 112N with the auxiliary drive circuits 12P, 12N (auxiliary 4) are provided on the inverter 5 side of the connection parts 111P, 111N. In addition, the positive side power supply circuit 11P is provided with a sixth contactor VS / C that turns the circuit ON / OFF between the connection part 112P with the auxiliary drive circuit 12P and the connection part 111P with the DC power supply circuit 13P. In addition, a first voltage sensor V_PIN, a first smoothing capacitor C1, and a second resistor R2 are provided on the inverter 5 side of the power supply circuits 11P, 11N. The first voltage sensor V_PIN, the first smoothing capacitor C1, and the second resistor R2 are provided on a circuit connecting the positive power supply circuit 11P and the negative power supply circuit 11N. The second resistor R2 is provided to discharge the first smoothing capacitor C1 when the circuit is interrupted.

[0031] The DC power supply circuits 13P, 13N are configured as a pair of positive and negative terminals, with one end provided with charging terminals 131P, 131N to which an external power source such as a charging facility can be connected, and the other end connected to the power supply circuits 11P, 11N via connectors 111P, 111N. The DC power supply circuits 13P, 13N are provided with seventh contactors QC / C_A and eighth contactors QC / C_B that turn the respective circuits ON / OFF. A second voltage sensor V_BAT is provided at a position closer to the connectors 111P, 111N than the seventh contactors QC / C_A and eighth contactors QC / C_B. A third voltage sensor V_QC is provided at a position closer to the charging terminals 131P, 131N than the seventh contactors QC / C_A and eighth contactors QC / C_B.

[0032] Branch circuit 14 branches off from positive-side DC power supply circuit 13P at a position closer to connection 111P than the eighth contactor QC / C_A and the second voltage sensor V_BAT, and is connected to one of the coils of three-phase motor 3 via connection 34. A ninth contactor QC / C_C that turns the circuit on and off is provided in the middle of branch circuit 14.

[0033] The control unit 10 is, for example, a vehicle ECU, and controls the driving and charging of the charging system 1. More specifically, the control unit 10 controls the ON / OFF of each of the contactors M / C, S / C_A, S / C_B, S / C_C, P / C, VS / C, QC / C_A, QC / C_B, and QC / C_C, detects welding of these contactors, controls the inverter 5, and so on.

[0034] Next, the operation of the charging system 1 will be described with reference to FIGS.

[0035] FIG. 4 is a diagram showing the flow of current when the electric vehicle equipped with the charging system 1 of the first embodiment is running (driven at 800V).

[0036] As described above, the electric vehicle equipped with the charging system 1 drives the three-phase motor 3 and the accessories 4 with a base voltage of 800V, and when traveling, the battery 2 is controlled to the 800V start state shown in Fig. 2. In addition, the control unit 10 turns on the first contactor M / C and the sixth contactor VS / C, and turns off the seventh contactor QC / C_A, the eighth contactor QC / C_B, and the ninth contactor QC / C_C.

[0037] In this mode, a voltage of 800V is supplied from the battery 2 to the three-phase motor 3 via the inverter 5, enabling the electric vehicle to run. At this time, the accessories 4 are driven by a voltage of 800V supplied from the battery 2 via the power supply circuits 11P, 11N and the accessory drive circuits 12P, 12N.

[0038] FIG. 5 is a diagram showing the current flow during second voltage charging (800 V charging) of the electric vehicle equipped with the charging system 1 of the first embodiment.

[0039] When charging with an 800V-class charging facility, the battery 2 is controlled to the 800V start-up state shown in Fig. 2. The control unit 10 also turns on the first contactor M / C, the seventh contactor QC / C_A, the eighth contactor QC / C_B, and the sixth contactor VS / C, and turns off the ninth contactor QC / C_C. As a result, a voltage of 800V is supplied to the battery 2 from the charging terminals 131P and 131N, and also to the auxiliary equipment 4 via the power supply circuit 11P and the auxiliary equipment drive circuit 12P.

[0040] FIG. 6 is a diagram showing the current flow during second voltage charging (400V charging) of the electric vehicle equipped with the charging system 1 of the first embodiment.

[0041] When charging with a 400V-class charging facility, the battery 2 is controlled to the 400V start-up state shown in Fig. 3. The control unit 10 also turns on the first contactor M / C, the seventh contactor QC / C_A, the eighth contactor QC / C_B, and the ninth contactor QC / C_C, and turns off the sixth contactor VS / C. As a result, a voltage of 400V is supplied to the battery 2 from the charging terminals 131P and 131N, and a voltage of 400V is supplied to the U-phase coil 32U via the branch circuit 14. Furthermore, turning off the sixth contactor VS / C cuts off the power supply from the battery 2 to the auxiliary equipment 4.

[0042] Here, in order to drive the auxiliary device 4 whose base voltage is 800V, it is necessary to boost the voltage of 400V to an auxiliary device driving voltage which is the driving voltage for the auxiliary device 4. The auxiliary device driving voltage may or may not be 800V.

[0043] Next, the configuration of the inverter 5 and the voltage step-up operation performed by the three-phase motor 3 and the inverter 5 will be described with reference to FIGS.

[0044] FIG. 7 is a schematic diagram showing a schematic configuration of the charging system 1 of the first embodiment. 7 , the inverter 5 includes a first tributary circuit 51 including a first high-side switch TH1, a first low-side switch TL1, and a first node P1 connecting the first high-side switch TH1 and the first low-side switch TL1 in series, a second tributary circuit 52 including a second high-side switch TH2, a second low-side switch TL2, and a second node P2 connecting the second high-side switch TH2 and the second low-side switch TL2 in series, and a third tributary circuit 53 including a third high-side switch TH3, a third low-side switch TL3, and a third node P3 connecting the third high-side switch TH3 and the third low-side switch TL3 in series. The high-side switch sides of the first tributary circuit 51, the second tributary circuit 52, and the third tributary circuit 53 are connected in parallel to the positive power supply circuit 11P and the low-side switch sides of the first tributary circuit 51, the second tributary circuit 52, and the third tributary circuit 53 are connected in parallel to the positive power supply circuit 11P and the negative power supply circuit 11N.

[0045] First node P1 is connected to U-phase terminal 33U and therefore to U-phase coil 32U, second node P2 is connected to V-phase terminal 33V and therefore to V-phase coil 32V, and third node P3 is connected to W-phase terminal 33W and therefore to W-phase coil 32W. Switches TH1, TL1, TH2, TL2, TH3, and TL3 are configured with, for example, MOSFETs, and are opened and closed by control unit 10 adjusting the gate voltage.

[0046] A diode that functions as a freewheeling diode is connected in parallel to each of the switches TH1, TL1, TH2, TL2, TH3, and TL3. The freewheeling diodes are provided to prevent damage to the switching elements by returning (regenerating) the current that flows back from the motor 3 side to the battery 2 side when the switches TH1, TL1, TH2, TL2, TH3, and TL3 are turned off. That is, the inverter 5 allows current to flow from the three-phase motor 3 side to the battery 2 side regardless of whether the gate is on or off, and allows current to flow from the battery 2 side to the three-phase motor 3 side only when the gate is on.

[0047] When charging with a 400V-class charging facility, the control unit 10 controls the charging system 1 to the state shown in FIG. 6 described above. As a result, a voltage of 400V is supplied to the battery 2 from the charging terminals 131P, 131N, and a voltage of 400V is supplied to the U-phase coil 32U via the branch circuit 14. Furthermore, because the power supply from the battery 2 to the auxiliary equipment 4 is cut off, it is necessary to boost the voltage of 400V to the auxiliary equipment drive voltage of the auxiliary equipment 4 in order to drive the auxiliary equipment 4. In the following description, the boosted voltage corresponding to the auxiliary equipment drive voltage may be referred to as the secondary voltage.

[0048] FIG. 8 is a diagram showing the current flow during two-phase boosting during charging at the second voltage (400 V) in the charging system 1 of the first embodiment. 6, the control unit 10 performs a boost operation by switching the second low-side switch TL2 and the third low-side switch TL3 between an ON state and an OFF state of the second low-side switch TL2 and the third low-side switch TL3. Note that the other switches TL1 and TH1 to TH3 of the inverter 5 are maintained in the OFF state.

[0049] As a result, the energy stored in coils 32U, 32V, and 32W when the second low-side switch TL2 and the third low-side switch TL3 are in the ON state is released when the second low-side switch TL2 and the third low-side switch TL3 are in the OFF state, and the 400V voltage supplied from the charging terminals 131P and 131N is boosted to a secondary voltage and supplied from the inverter 5 to the auxiliary device 4. Hereinafter, this boost operation state by the three-phase motor 3 and the inverter 5 is referred to as two-phase boost mode.

[0050] FIG. 9 is a diagram showing the current flow during one-phase boosting during charging at the second voltage (400 V) in the charging system 1 of the first embodiment. 6, the control unit 10 performs a boost operation by switching the third low-side switch TL3 between an ON state and an OFF state of the third low-side switch TL3 by high-frequency switching. Note that the other switches TL1, TL2, and TH1 to TH3 of the inverter 5 are maintained in the OFF state.

[0051] As a result, the energy stored in coils 32U and 32W when the third low-side switch TL3 is in the ON state is released when the third low-side switch TL3 is in the OFF state, and the 400 V voltage supplied from the charging terminals 131P and 131N is boosted to a secondary voltage and supplied from the inverter 5 to the auxiliary device 4. Hereinafter, this boost operation state by the three-phase motor 3 and the inverter 5 is referred to as the single-phase boost mode.

[0052] In the electric vehicle 100, when the power supplied to the auxiliary device 4 is boosted in the two-phase boost mode or one-phase boost mode described above during charging to the second voltage (400V), a magnetic field is generated by the current flowing through the coils 32U, 32V, and 32W, and torque is generated in the three-phase motor 3. Therefore, depending on the situation, there is a risk that the rotor 37 may rotate, and when the rotor 37 rotates, there is a risk that the wheel W connected to the rotor 37 may also rotate.

[0053] The magnitude of the torque generated by the three-phase motor 3 during two-phase voltage boosting and one-phase voltage boosting varies depending on the angle of the rotor 37 when the electric vehicle 100 is parked.

[0054] Fig. 10 is a graph showing the currents flowing through coils 32U, 32V, and 32W when electric vehicle 100 is running, and Fig. 11 is a diagram showing the positional relationship between stator 35 and rotor 37 (permanent magnet 36) of three-phase motor 3 in (A) to (D) of Fig. 10. Figs. 10 and 11 show an example of a two-pole, three-slot motor as three-phase motor 3.

[0055] For example, as shown in Figures 10 and 11, based on the currents flowing through coils 32U, 32V, and 32W when electric vehicle 100 is traveling, if the position where U-phase current is zero, V-phase current is negative, and W-phase current is positive as shown in Figures 10 and 11(A) is defined as 0° electrical angle and the direction in which U-phase current becomes positive is defined as the positive electrical angle, then the torque generated in three-phase motor 3 is maximum at an electrical angle of 90° as shown in Figures 10 and 11(B) and the torque generated in three-phase motor 3 is minimum at an electrical angle of 270° as shown in Figures 10 and 11(D).

[0056] 15(B), when the claw portion 82 of the parking pole 81 comes into contact with the convex portion 85 of the parking gear 83, the parking gear 83 can rotate until the claw portion 82 of the parking pole 81 meshes with the concave portion 84 of the parking gear 83, and accordingly the wheel W can also rotate. The EPB 7 is controlled between an operating state and an inoperating state in response to a user operation.

[0057] Therefore, when parking the electric vehicle 100, even if the claw portion 82 of the parking pole 81 abuts the protrusion 85 of the parking gear 83, rotation of the wheels W is restricted if the user has activated the EPB 7. On the other hand, when parking the electric vehicle 100, if the claw portion 82 of the parking pole 81 abuts the protrusion 85 of the parking gear 83 but the user has not activated the EPB 7, the parking gear 83 can rotate until the claw portion 82 of the parking pole 81 engages with the recess 84 of the parking gear 83. Therefore, if the battery 2 is charged with the second voltage (400 V) in this state, there is a risk that the wheels W will rotate due to the torque generated in the three-phase motor 3.

[0058] Therefore, in order to restrict movement of electric vehicle 100 during charging at the second voltage (400 V), control unit 10 forcibly activates EPB 7 when it detects that a charging plug has been fitted to charging terminals 131P, 131N and that the charging voltage of battery 2 is 400 V. In other words, when control unit 10 detects that a charging plug has been fitted to charging terminals 131P, 131N and that the charging voltage of battery 2 is 400 V, even if EPB 7 is in an inactive state, it forcibly controls EPB 7 to an active state regardless of the user's intention. This makes it possible to prevent electric vehicle 100 from moving forward or backward during charging at the second voltage (400 V).

[0059] FIG. 12 is a flowchart of the charge start control during second voltage (400V) charging. First, the control unit 10 detects whether the electric vehicle 100 is stopped (step S1). Next, the control unit 10 detects whether the shift is in the parking range (P range) (step S2). As a result, if the shift is not in the parking range (P range) (NO in step S2), the control unit 10 determines that the electric vehicle 100 is stopped and the user has no intention of charging, and ends the process.

[0060] If the shift is in parking (P range) (YES in step S2), the control unit 10 then detects whether the charging plug is engaged with the charging terminals 131P, 131N (step S3). If the charging plug is not engaged with the charging terminals 131P, 131N (NO in step S3), the control unit 10 determines that the user has no intention of charging and ends the process. On the other hand, if the charging plug is engaged with the charging terminals 131P, 131N, the control unit 10 communicates with the charging equipment and detects the charging voltage on the charging equipment side (step S4).

[0061] As a result, if the charging voltage is 800V or if charging is AC charging, voltage boost control using the coils 32U, 32V, and 32W of the three-phase motor 3 is not performed, so no torque is generated in the three-phase motor 3 and the electric vehicle 100 does not move. Therefore, charging starts as is (step S5). On the other hand, if the charging voltage on the charging equipment side is 400V, the control unit 10 checks the operating state of the EPB 7 (step S8). If the EPB 7 is in an activated state (ON in step S6), voltage boost starts as is. On the other hand, if the EPB 7 is in an inactivated state (OFF in step S6), the EPB 7 is forcibly activated (step S7) and voltage boost starts (step S8).

[0062] Here, by putting the EPB 7 into an operating state, the movement of the electric vehicle 100 in the forward and backward directions is restricted, but the torque generated by the three-phase motor 3 may act as a rocking motion of the electric vehicle 100 in the up and down directions.

[0063] FIG. 13 is a graph showing the relationship between the rate of change of current (di / dt) and acceleration (G) during charging at the second voltage (400V). As shown in Fig. 13, when the current change rate (di / dt) obtained by differentiating the output current (i) with respect to time (t) during charging at the second voltage (400V) is large, the acceleration G increases and the vehicle behavior becomes rough. Therefore, when one-phase or two-phase voltage increase is performed to 800V during charging at the second voltage (400V), the control unit 10 performs vehicle behavior mitigation control so that the current change rate is equal to or less than a predetermined value (step S9), and then starts charging (step S10). In this way, by controlling the current change rate during charging at the second voltage (400V) to be equal to or less than a predetermined value, the behavior of the electric vehicle 100 can be mitigated.

[0064] Furthermore, when charging of the battery 2 is completed, the control unit 10 performs vehicle behavior mitigation control so that the current change rate is equal to or less than a predetermined value (step S9), and then ends charging. Furthermore, if the EPB 7 is controlled to be in an activated state regardless of the user's intention, the EPB 7 is returned to an inactivated state when charging to the second voltage (400 V) is completed. This prevents the EPB 7 from being maintained in an activated state against the user's intention.

[0065] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components of the above-described embodiments may be combined in any manner without departing from the spirit of the invention.

[0066] This specification describes at least the following items. Note that the components in parentheses correspond to those in the above-described embodiment, but are not limited to these.

[0067] (1) Battery (Battery 2) and a motor (three-phase motor 3) that drives the wheels (wheels W); an inverter (inverter 5) that converts DC power from the battery into AC power and supplies the AC power to the motor; a charging terminal (131P) connected to the battery when charging the battery and connected to a coil of one phase of the motor; an electric device (auxiliary device 4) that is driven by a first voltage (800V) from the battery when the battery is being discharged, and that is driven by the first voltage boosted by the motor and the inverter when the battery is being charged by a second voltage (400V) lower than the first voltage; a control unit (control unit 10) that controls charging of the battery; A vehicle (electric vehicle 100) including a brake mechanism (EPB7) that restricts rotation of the wheel, The control unit activating the brake mechanism when it is detected that a charging plug has been fitted to the charging terminal and when it is detected that the charging voltage of the battery is the second voltage; vehicle.

[0068] When charging the battery at a second voltage lower than the first voltage that drives the electrical equipment, if the motor and inverter are used to boost the voltage to the first voltage, torque will be generated in the motor. According to (1), when it is detected that the charging plug has been mated with the charging terminal and that the charging voltage of the battery is the second voltage, the brake mechanism is activated to prevent the vehicle from moving forward or backward.

[0069] (2) The vehicle according to (1), The control unit When charging the battery with the second voltage, the current change rate is controlled to be equal to or less than a predetermined value. vehicle.

[0070] According to (2), when the vehicle's forward / backward movement is restricted by a brake mechanism, the motor torque acts to cause the vehicle to sway up and down. However, when the battery is charged with the second voltage, the vehicle behavior can be alleviated by controlling the current change rate to be below a predetermined value.

[0071] (3) A vehicle according to (1) or (2), a disconnecting device (sixth contactor VS / C) is provided in a power transmission path between the battery and the electrical device; When the battery is charged at the second voltage, the disconnecting device interrupts power transmission between the battery and the electrical device. vehicle.

[0072] According to (3), when the battery is charged with the second voltage, the second voltage from the charging equipment can be prevented from being supplied to an electric device that is driven by the first voltage. [Explanation of symbols]

[0073] 2 Battery 3 Three-phase motor (motor) 4. Auxiliary equipment (electrical equipment) 5 inverters 10 Control Unit 100 Electric Vehicles (Vehicles) 131P charging terminal 400V (second voltage) 800V (first voltage) VS / C 6th contactor (disconnecting device) EPB7 (Brake mechanism) W wheels

Claims

1. A battery, a motor that drives the wheels; an inverter that converts DC power from the battery into AC power and supplies the AC power to the motor; a charging terminal connected to the battery when charging the battery and connected to a coil of any one phase of the motor; an electric device that is driven by a first voltage from the battery when the battery is being discharged, and that is driven by the first voltage boosted by the motor and the inverter when the battery is being charged by a second voltage lower than the first voltage; a control unit that controls charging of the battery; A vehicle equipped with a brake mechanism that restricts rotation of the wheel, The control unit activating the brake mechanism when it is detected that a charging plug has been fitted to the charging terminal and when it is detected that the charging voltage of the battery is the second voltage; vehicle.

2. 2. The vehicle according to claim 1, The control unit When charging the battery with the second voltage, a current change rate is controlled to be equal to or less than a predetermined value. vehicle.

3. 3. A vehicle according to claim 1 or 2, a disconnecting device is provided in a power transmission path between the battery and the electrical device; When the battery is charged at the second voltage, the disconnecting device interrupts power transmission between the battery and the electrical device. vehicle.

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