Vehicle

Abstract

The present invention provides a vehicle capable of suppressing an increase in vehicle operation when torque is generated by a motor during charging. An electric vehicle (100) is provided with: a battery (2); a three-phase motor (3); an inverter (5); a charging terminal (131P) that is connected to the battery (2) when the battery (2) is charged and that is connected to a coil (32U) of any one phase of the three-phase motor (3); an auxiliary machine (4) that is driven at a voltage of 800 V from the battery (2) when the battery (2) is discharged, and that is driven at a voltage of 800 V boosted by the three-phase motor (3) and the inverter (5) when the battery (2) is charged at a voltage of 400 V; a control unit (10) that controls the charging of the battery (2); and an EPB (7) that restricts the rotation of the wheel (W). When it is detected that the charging plug is fitted to the charging terminals (131P, 131N) and that the charging voltage of the battery (2) is 400 V, the control unit (10) operates the EPB (7).

Description

Technical Field

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

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

[0003] Regarding charging power supply for mobile objects equipped with secondary batteries, charging facilities such as charging stations have two types of charging facilities: 400V class with a maximum voltage of 500 V and 800V class with a maximum voltage of 1000 V. If a mobile object only supports 400V class charging facilities or 800V class charging facilities, it cannot enjoy fast charging performance.

[0004] Therefore, for example, Patent Document 1 describes 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 an individual charging mode in which either battery is charged to match the charging voltage of the charging facility.

[0005] Patent Document 1 also states that since a motor is disposed on the power transmission path of the two batteries, when charging current flows through the coil of the motor, torque is generated by the charging current, causing the motor to rotate.

[0006] In contrast, Patent Document 1 describes starting charging after the motor rotor is moved to a zero torque position after the vehicle stops. However, when the motor rotor is moved after the vehicle stops, the parking brake needs to be temporarily released.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent No. 7244075 Summary of the Invention

[0010] Problems to be solved by the invention

[0011] Yet, because releasing the parking brake and making the vehicle move is that the user does not wish, so is not preferred.In addition, also imagine the situation that the vehicle cannot be moved because of obstacles etc.

[0012] The present invention provides a vehicle capable of suppressing the vehicle from moving more violently when a motor generates torque during charging.

[0013] Means for solving problems

[0014] The present invention relates to a vehicle comprising:

[0015] batteries;

[0016] a motor, which drives the wheels;

[0017] an inverter that converts DC power from the battery into AC power and supplies the AC power to the motor;

[0018] a charging terminal connected to the battery when the battery is charged and connected to a coil of any one phase of the motor;

[0019] an electric device that is driven by a first voltage from the battery when the battery is discharged, and is driven by the first voltage boosted by the motor and the inverter when the battery is charged at a second voltage lower than the first voltage;

[0020] a control unit that controls charging of the battery; and

[0021] a braking mechanism that limits the wheel rotation,

[0022] The control unit activates the brake mechanism when detecting that a charging plug is fitted into the charging terminal and further detecting that the charging voltage of the battery is the second voltage.

[0023] Effects of the Invention

[0024] According to the present invention, it is possible to suppress the vehicle from moving more rapidly in a situation where the motor generates torque during charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 1 is a diagram showing a configuration of a charging system 1 mounted on an electric vehicle 100 according to an embodiment of the present invention.

[0026] Figure 2 This is a diagram showing the first voltage state (800V starting) of the battery 2 .

[0027] Figure 3 1 is a diagram showing the second voltage state (400 V starting) of the battery 2 .

[0028] Figure 4 1 is a diagram showing the flow of current when electric vehicle 100 is traveling.

[0029] Figure 5 1 is a diagram showing the flow of current when electric vehicle 100 is charged at a first voltage (800 V).

[0030] Figure 6 1 is a diagram showing the flow of current when electric vehicle 100 is charged at the second voltage (400 V).

[0031] Figure 7 It is a schematic diagram showing a schematic configuration of the charging system 1 .

[0032] Figure 8 1 is a diagram showing the flow of current during two-phase voltage boosting when the charging system 1 is charging at the second voltage (400 V).

[0033] Figure 9 This is a diagram showing the flow of current during single-phase voltage boosting when the charging system 1 is charging at the second voltage (400 V).

[0034] Figure 10 Graph showing currents flowing through coils 32U, 32V, and 32W when electric vehicle 100 is traveling.

[0035] Figure 11 Yes Figure 10 1 and 2 are diagrams showing the positional relationship between the stator 35 and the rotor 37 (permanent magnet 36 ) of the three-phase motor 3 in (A) to (D).

[0036] Figure 12 This is a flowchart of charge start control when charging at the second voltage (400 V).

[0037] Figure 13 This is a graph showing the relationship between the current change rate (di / dt) and acceleration (G) when charging at the second voltage (400 V).

[0038] Figure 14 It is a schematic side view illustrating an electric vehicle 100 according to one embodiment of the present invention.

[0039] Figure 15 1 is a diagram illustrating a parking mechanism of electric vehicle 100 .

[0040] Description of Reference Numerals

[0041] 2 batteries

[0042] 3 Three-phase motor (motor)

[0043] 4 Auxiliary equipment (electrical equipment)

[0044] 5 Inverter

[0045] 10. Control Unit

[0046] 100 Electric vehicles (vehicles)

[0047] 131P charging terminal

[0048] 400V (second voltage)

[0049] 800V (first voltage)

[0050] VS / C Sixth contactor (disconnect device)

[0051] EPB7 (brake mechanism)

[0052] W wheel. DETAILED DESCRIPTION

[0053] Hereinafter, an electric vehicle 100 according to an embodiment of the present invention will be described with reference to the drawings.

[0054] like Figure 14 As shown, the electric vehicle 100 is equipped with a charging system 1 (see Figure 1 ) electric vehicles, such as electric vehicles, hybrid vehicles, and fuel cell vehicles, can travel by driving a three-phase motor 3 using power supplied from a battery 2. Electric vehicle 100 is equipped with wheel brakes 6, an EPB (Electric Parking Brake) 7 that restricts rear wheel rotation, and a parking mechanism 8 that restricts front wheel rotation.

[0055] The wheel brake 6 is, for example, a hydraulic brake, and applies braking force to the wheel W in response to a user's operation of a brake pedal.

[0056] The parking mechanism 8 becomes the working state when the gear is in the parking gear. Figure 15 As shown in FIG. 8A , when the pawl portion 82 of the parking pawl 81 meshes with the recessed portion 84 of the parking gear 83 , the rotation of the parking gear 83 is restricted, and the rotation of the wheels W (front wheels) is also restricted accordingly.

[0057] The EPB 7 is controlled to be in an operating state or a non-operating state according to a user operation. Therefore, even when the electric vehicle 100 is parked, there may be two situations: one in which the EPB 7 is in an operating state and the other in which it is non-operating.

[0058] The charging system 1 supports 400V and 800V charging equipment, and can not only quickly charge the battery 2 at 400V and 800V charging voltages, but also drive the three-phase motor 3 and auxiliary equipment 4 at a basic voltage of 800V.

[0059] Specifically, if Figure 1 As shown, charging system 1 includes a battery 2 , a three-phase motor 3 , auxiliary equipment 4 , an inverter 5 (INV), power supply circuits 11P and 11N, auxiliary equipment drive circuits 12P and 12N, DC power supply circuits 13P and 13N, a branch circuit 14 , and a control unit 10 .

[0060] like Figures 1 to 3As shown, the battery 2 includes a first power storage unit 21 , a second power storage unit 22 , first to fifth contactors M / C, S / C_A, S / C_B, S / C_C, P / C, a first resistor R1 , a current sensor IS, and a current breaker FUSE.

[0061] The first power storage unit 21 and the second power storage unit 22 are each a battery module capable of 400V charge and discharge.

[0062] The first contactor M / C is disposed at the end portion on the positive electrode side of the battery 2 , and functions as a main switch for opening and closing the connection with the outside of the battery 2 (the power supply circuit 11P).

[0063] 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. Figure 2 As shown in FIG. 1 , if 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 is in the first voltage state (800V start) where the first storage unit 21 and the second storage unit 22 are connected in series, and charging and discharging at 800V are possible. Figure 3 As shown, when the second contactor S / C_A is opened and the third contactor S / C_B and the fourth contactor S / C_C are closed, the battery 2 enters the second voltage state (400 V starting) in which the first power storage unit 21 and the second power storage unit 22 are connected in parallel, enabling charging and discharging at 400 V. The term "starting" encompasses both driving the electric vehicle equipped with the charging system 1 while it is traveling and charging the electric vehicle while it is parked.

[0064] The fifth contactor P / C is connected in series with the first resistor R1 and in parallel with the first contactor M / C. The fifth contactor P / C is turned on before the first contactor M / C is turned on, in both the first and second voltage states, thereby protecting the first contactor M / C from excessive inrush current.

[0065] Current sensor IS is disposed between first contactor M / C and power storage units 21 and 22 to measure current.

[0066] A circuit breaker FUSE is located at the negative-pole end of battery 2. It disconnects battery 2 from the outside (power supply circuit 11N) in the event of an abnormality. In the charging system 1 of this embodiment, the circuit breaker FUSE is a high-temperature fuse that actively interrupts current in response to an electrical signal. In the event of an abnormality (such as a vehicle collision or a short circuit within battery 2), the circuit breaker FUSE is activated, disconnecting all contactors within battery 2 (opening the circuit).

[0067] 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 permanent magnets 36 are arranged (see FIG. Figure 11 One end of each of the three-phase coils 32U, 32V, and 32W is connected at a neutral point 31, and the other end is connected to the inverter 5 via a U-phase terminal 33U, a V-phase terminal 33V, and a W-phase terminal 33W. Furthermore, the other end of each of the three-phase coils 32U, 32V, and 32W is connected to the branch circuit 14 at a connection 34. In this embodiment, the U-phase coil 32U of the three-phase coils 32U, 32V, and 32W is connected to the branch circuit 14 at a connection 34 located between the U-phase terminal 33U and the inverter 5.

[0068] The inverter 5 converts the DC power supplied from the battery 2 into three-phase AC power by switching its multiple switching elements, thereby rotating the three-phase motor 3. Furthermore, when DC current (400V) is supplied from the branch circuit 14 to the connection portion 34, the inverter 5 can function as a boost circuit (DC voltage converter) by switching its multiple switching elements, boosting the DC current using the coil connected to the branch circuit 14 and the coils of one or two other phases. Details will be described later.

[0069] The auxiliary equipment 4 is an onboard device capable of being driven by DC power from the battery 2 and an external power supply. Examples include the electric compressor E-COMP for the air conditioner (A / C), the electric heater ECH, and the auxiliary equipment converter DCDC. The electric compressor E-COMP and the electric heater ECH are high-voltage onboard devices, while the auxiliary equipment converter DCDC steps down the DC power from the battery 2 and the external power supply to drive low-voltage onboard devices. The auxiliary equipment 4 is connected to the battery 2 via the auxiliary equipment drive circuits 12P and 12N, the sixth contactor VS / C, and the power supply circuits 11P and 11N. In this embodiment, the auxiliary equipment 4 operates at a base voltage of 800V while the vehicle is traveling. However, the auxiliary equipment 4 is configured to operate even at voltages other than 800V. When charging at 400V, as described later, the voltage is stepped up to a more efficient drive voltage for operation.

[0070] Power supply circuits 11P and 11N consist of a positive and negative pair, connecting the battery 2 to the inverter 5 (three-phase motor 3). Connectors 111P and 111N are provided on the power supply circuits 11P and 11N, which connect to the DC power supply circuits 13P and 13N. Connectors 112P and 112N are provided on the inverter 5 side of connectors 111P and 111N, which connect to the auxiliary machine drive circuits 12P and 12N (auxiliary machine 4). Furthermore, a sixth contactor VS / C is provided on the positive-side power supply circuit 11P, which connects between connector 112P, which connects to the auxiliary machine drive circuit 12P, and connector 111P, which connects to the DC power supply circuit 13P. Furthermore, 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 and 11N. The first voltage sensor V_PIN, the first smoothing capacitor C1, and the second resistor R2 are provided in 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 disconnected.

[0071] The DC power supply circuits 13P and 13N consist of a pair of positive and negative terminals. Charging terminals 131P and 131N, which can be connected to an external power source such as a charger, are located at one end of each circuit. The other ends are connected to the power supply circuits 11P and 11N via connectors 111P and 111N. The DC power supply circuits 13P and 13N are equipped with a seventh contactor QC / C_A and an eighth contactor QC / C_B, which connect and disconnect the respective circuits. Furthermore, a second voltage sensor V_BAT is located closer to the connectors 111P and 111N than the seventh and eighth contactors QC / C_A and QC / C_B. Furthermore, a third voltage sensor V_QC is located closer to the charging terminals 131P and 131N than the seventh and eighth contactors QC / C_A and QC / C_B.

[0072] The branch circuit 14 branches off from the positive-side DC power supply circuit 13P at a position closer to the connection portion 111P than the eighth contactor QC / C_A and the second voltage sensor V_BAT, and is connected to any coil of the three-phase motor 3 via the connection portion 34. A ninth contactor QC / C_C for switching the circuit on and off is provided in the middle of the branch circuit 14.

[0073] 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 state of each contactor (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 melting of these contactors, and controls the inverter 5.

[0074] Next, refer to Figures 4 to 6 The operation of the charging system 1 will be described.

[0075] Figure 4 This is a diagram showing the flow of current when the electric vehicle equipped with the charging system 1 according to the first embodiment is traveling (800 V drive).

[0076] As described above, the electric vehicle equipped with the charging system 1 drives the three-phase motor 3 and the auxiliary machine 4 at a base voltage of 800V. When the vehicle is running, the battery 2 is controlled to Figure 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.

[0077] In this mode, 800V is supplied from battery 2 to three-phase motor 3 via inverter 5, enabling the electric vehicle to travel. Auxiliary machine 4 is driven by 800V supplied from battery 2 via power supply circuits 11P, 11N and auxiliary machine drive circuits 12P, 12N.

[0078] Figure 5 This is a diagram showing the flow of current when an electric vehicle equipped with the charging system 1 according to the first embodiment is charged at a first voltage (800 V charging).

[0079] When charging with 800V class charging equipment, the battery 2 is controlled to Figure 2 The 800V startup state is shown. Furthermore, the control unit 10 closes the first contactor M / C, the seventh contactor QC / C_A, the eighth contactor QC / C_B, and the sixth contactor VS / C, and opens the ninth contactor QC / C_C. This supplies 800V to the battery 2 from the charging terminals 131P and 131N, and also supplies 800V to the auxiliary equipment 4 via the power supply circuit 11P and the auxiliary equipment drive circuit 12P.

[0080] Figure 6 This is a diagram showing the flow of current when the electric vehicle equipped with the charging system 1 according to the first embodiment is charged at the second voltage (400 V charging).

[0081] When charging with a 400V class charging device, the battery 2 is controlled to Figure 3The 400V startup state is shown. Furthermore, the control unit 10 closes 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 opens the sixth contactor VS / C. This supplies a 400V voltage to the battery 2 from the charging terminals 131P and 131N, and also supplies a 400V voltage to the U-phase coil 32U via the branch circuit 14. Furthermore, by opening the sixth contactor VS / C, the power supply from the battery 2 to the auxiliary machine 4 is cut off.

[0082] Here, in order to drive the auxiliary machine 4 having a base voltage of 800V, it is necessary to boost the voltage of 400V to the auxiliary machine driving voltage, which is the driving voltage of the components of the auxiliary machine 4. The auxiliary machine driving voltage may or may not be 800V.

[0083] Next, refer to Figures 7 to 9 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.

[0084] Figure 7 It is a schematic diagram showing a schematic configuration of a charging system 1 according to the first embodiment.

[0085] like Figure 7 As shown, the inverter 5 includes a first branch circuit 51 having 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 branch circuit 52 having 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 branch circuit 53 having 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-side ends of the first branch circuit 51, the second branch circuit 52, and the third branch circuit 53 are connected in parallel to the positive-side power supply circuit 11P, and the low-side switch-side ends are connected in parallel to the negative-side power supply circuit 11N.

[0086] Furthermore, first node P1 is connected to U-phase terminal 33U and thus to U-phase coil 32U. Second node P2 is connected to V-phase terminal 33V and thus to V-phase coil 32V. Third node P3 is connected to W-phase terminal 33W and thus to W-phase coil 32W. Switches TH1, TL1, TH2, TL2, TH3, and TL3 are each formed, for example, of MOSFETs, and are controlled by gate voltage adjustment by control unit 10.

[0087] Diodes functioning as freewheeling diodes are connected in parallel with each of the switches TH1, TL1, TH2, TL2, TH3, and TL3. These freewheeling diodes prevent damage to the switching elements by allowing current flowing backward from the motor 3 to flow back (regenerate) to the battery 2 when the switches TH1, TL1, TH2, TL2, TH3, and TL3 are turned off. Specifically, the inverter 5 allows current to flow from the three-phase motor 3 to the battery 2 regardless of whether the gate is on or off. Current is only allowed to flow from the battery 2 to the three-phase motor 3 when the gate is on.

[0088] When charging is performed using a 400V class charging device, the control unit 10 controls the charging system 1 to the aforementioned Figure 6 As a result, a voltage of 400 V is supplied to the battery 2 from the charging terminals 131P and 131N, and a voltage of 400 V is supplied to the U-phase coil 32U via the branch circuit 14. Furthermore, since the power supply from the battery 2 to the auxiliary machine 4 is cut off, it is necessary to boost the 400 V voltage to the auxiliary machine drive voltage for the auxiliary machine 4 in order to drive the auxiliary machine 4. In the following description, the boosted voltage corresponding to the auxiliary machine drive voltage may be referred to as a secondary voltage.

[0089] Figure 8 This is a diagram showing the flow of current during two-phase boosting when the charging system 1 of the first embodiment is charging at the second voltage (400 V).

[0090] Therefore, the control unit 10 Figure 6 In this state, the second low-side switch TL2 and the third low-side switch TL3 are switched at high frequency, performing a boost operation that switches between the on state and the off state of the second low-side switch TL2 and the third low-side switch TL3. Furthermore, the other switches TL1 and TH1 to TH3 of the inverter 5 remain in the off state.

[0091] Thus, the energy stored in coils 32U, 32V, and 32W when second and third low-side switches TL2 and TL3 are on is released when second and third low-side switches TL2 and TL3 are off. As a result, the 400V voltage supplied from charging terminals 131P and 131N is boosted to a secondary voltage and supplied from inverter 5 to auxiliary equipment 4. This voltage boosting operation performed by three-phase motor 3 and inverter 5 is hereinafter referred to as a two-phase boost mode.

[0092] Figure 9 This is a diagram showing a current flow during a single-phase boosting operation when the charging system 1 according to the first embodiment is charging at the second voltage (400 V).

[0093] In addition, the control unit 10 Figure 6In the state of , the third low-side switch TL3 is switched at high frequency to perform a boost operation by switching the third low-side switch TL3 between the on state and the off state. In addition, the other switches TL1, TL2 and TH1 to TH3 of the inverter 5 remain in the off state.

[0094] As a result, the energy stored in coils 32U and 32W when the third low-side switch TL3 is on is released when the third low-side switch TL3 is off. As a result, the 400V voltage supplied from charging terminals 131P and 131N is boosted to a secondary voltage and supplied from inverter 5 to auxiliary equipment 4. This state of boosting operation performed by the three-phase motor 3 and inverter 5 is hereinafter referred to as single-phase boost mode.

[0095] In electric vehicle 100, when charging at the second voltage (400V), when the power supplied to auxiliary equipment 4 is boosted in the aforementioned two-phase boost mode or single-phase boost mode, current flows through coils 32U, 32V, and 32W, generating a magnetic field and generating torque in three-phase motor 3. Consequently, depending on the situation, rotor 37 may rotate, and if rotor 37 rotates, wheels W coupled to rotor 37 may also rotate.

[0096] The magnitude of the torque generated by the three-phase motor 3 during two-phase boosting and single-phase boosting varies depending on the angle of the rotor 37 when the electric vehicle 100 is parked.

[0097] Figure 10 is a graph showing the currents flowing through the coils 32U, 32V, and 32W when the electric vehicle 100 is traveling. Figure 11 Yes Figure 10 The positional relationship between the stator 35 and the rotor 37 (permanent magnet 36) of the three-phase motor 3 in (A) to (D) is shown. Figure 10 and Figure 11 In FIG, a two-pole three-slot motor is exemplified as the three-phase motor 3 .

[0098] For example, Figure 10 and Figure 11 As shown, based on the current flowing through the coils 32U, 32V, and 32W when the electric vehicle 100 is running, Figure 10 and Figure 11 When the position shown in (A) is set as 0° in electrical angle, the position where the U phase current is zero, the V phase current is negative, and the W phase current is positive, and the direction where the U phase current is positive is set as the positive direction of the electrical angle, Figure 10 and Figure 11 Under the condition of the electrical angle of 90° shown in (B), the torque generated in the three-phase motor 3 is the maximum. Figure 10 and Figure 11Under the condition of an electrical angle of 270° shown in (D), the torque generated in the three-phase motor 3 is minimum.

[0099] Here, when the parking mechanism 8 changes from the non-operating state to the operating state, as shown in FIG. Figure 15 As shown in (B), when the pawl portion 82 of the parking pawl 81 contacts the convex portion 85 of the parking gear 83, the parking gear 83 can rotate until the pawl portion 82 of the parking pawl 81 meshes with the concave portion 84 of the parking gear 83, and the wheel W can rotate accordingly. Furthermore, the EPB 7 is controlled between an operative state and a non-operative state according to user operation.

[0100] Therefore, when electric vehicle 100 is parked, even if the pawl 82 of parking pawl 81 abuts the convex portion 85 of parking gear 83, if the user has activated EPB 7, rotation of wheel W is restricted. On the other hand, when electric vehicle 100 is parked, even if the pawl 82 of parking pawl 81 abuts the convex portion 85 of parking gear 83, if the user has not activated EPB 7, parking gear 83 can rotate until the pawl 82 of parking pawl 81 engages the concave portion 84 of parking gear 83. Therefore, if battery 2 is charged at the second voltage (400V) in this state, wheel W may rotate due to the torque generated by three-phase motor 3.

[0101] Therefore, to restrict movement of the electric vehicle 100 during charging at the second voltage of 400V, the control unit 10 forcibly activates the EPB 7 when it detects that the charging plug is engaged with the charging terminals 131P and 131N and that the charging voltage of the battery 2 is 400V. In other words, even if the EPB 7 is in the inactive state, the control unit 10 forcibly activates the EPB 7 regardless of the user's intention when the charging plug is engaged with the charging terminals 131P and 131N and the charging voltage of the battery 2 is 400V, regardless of the user's intention. This prevents the electric vehicle 100 from moving forward and backward during charging at the second voltage (400V).

[0102] Figure 12 This is a flowchart of charge start control when charging at the second voltage (400 V).

[0103] First, the control unit 10 detects that the electric vehicle 100 is stopped (step S1). Next, the control unit 10 detects whether the shift position is in the parking position (P position) (step S2). If the shift position is not in the parking position (P position) (No in step S2), the electric vehicle 100 is parked and the user does not intend to charge the vehicle, so the process ends.

[0104] If the vehicle is in the parking position (P) (YES in step S2), the control unit 10 then checks whether the charging plug is engaged with charging terminals 131P and 131N (step S3). If the charging plug is not engaged with charging terminals 131P and 131N (NO in step S3), the user is deemed not to have intended to charge the vehicle, and the process ends. On the other hand, if the charging plug is engaged with charging terminals 131P and 131N, the control unit 10 communicates with the charging equipment to detect the charging voltage on the charging equipment side (step S4).

[0105] As a result, if the charging voltage is 800V or AC charging is used, the voltage boost control using coils 32U, 32V, and 32W of three-phase motor 3 is not performed. Therefore, no torque is generated in three-phase motor 3, and electric vehicle 100 does not move. Therefore, charging is resumed as is (step S5). On the other hand, if the charging voltage on the charger side is 400V, control unit 10 checks the operating status of EPB 7 (step S6). If EPB 7 is in the operating state (on in step S6), voltage boost is resumed as is. On the other hand, if EPB 7 is in the non-operating state (off in step S6), EPB 7 is forcibly switched to the operating state (step S7), and voltage boost is resumed (step S8).

[0106] Here, by operating the EPB 7 , the front-rear movement of the electric vehicle 100 is restricted. However, the torque generated by the three-phase motor 3 may act as a swing in the vertical direction of the electric vehicle 100 .

[0107] Figure 13 This is a graph showing the relationship between the current change rate (di / dt) and acceleration (G) when charging at the second voltage (400 V).

[0108] like Figure 13 As shown, when the current change rate (di / dt), obtained by differentiating the output current (i) during charging at the second voltage (400V) with respect to time (t), is large, acceleration G increases, and vehicle motion becomes more severe. Therefore, when performing a single-phase or two-phase voltage boost to 800V during charging at the second voltage (400V), the control unit 10 performs vehicle motion reduction control (step S9) to keep the current change rate below a predetermined value, and then begins charging (step S10). By controlling the current change rate during charging at the second voltage (400V) to below the predetermined value, the motion of the electric vehicle 100 can be reduced.

[0109] Furthermore, when charging of battery 2 is complete, the control unit 10 also performs vehicle motion reduction control (step S9) to keep the current change rate below a predetermined value, and then terminates charging. Furthermore, if the EPB 7 is forcibly controlled to operate regardless of the user's intention, the EPB 7 returns to the non-operating state upon completion of charging at the second voltage (400V). This prevents the EPB 7 from being maintained in the operating state against the user's will.

[0110] While various embodiments have been described above with reference to the accompanying drawings, the present invention is not limited to these examples. It is apparent that those skilled in the art will be able to devise various variations or modifications within the scope of the technical solutions described, and it should be understood that these variations and modifications also fall within the technical scope of the present invention. Furthermore, the various components of the above embodiments may be arbitrarily combined without departing from the spirit of the invention.

[0111] This specification includes at least the following matters: In addition, the components corresponding to those in the above-mentioned embodiment are shown in parentheses, but the present invention is not limited thereto.

[0112] (1) A vehicle (electric vehicle 100 ) comprising:

[0113] Battery (Battery2);

[0114] a motor (three-phase motor 3) that drives wheels (wheels W);

[0115] an inverter (inverter 5 ) that converts DC power from the battery into AC power and supplies the AC power to the motor;

[0116] a charging terminal (charging terminal 131P), which is connected to the battery when the battery is charged and is connected to a coil of any one phase of the motor;

[0117] an electric device (auxiliary device 4) that is driven by a first voltage (800 V) from the battery when the battery is discharged, and is driven by the first voltage boosted by the motor and the inverter when the battery is charged at a second voltage (400 V) lower than the first voltage;

[0118] a control unit (control unit 10 ) that controls charging of the battery; and

[0119] a brake mechanism (EPB7) which limits the wheel rotation,

[0120] in,

[0121] The control unit activates the brake mechanism when detecting that a charging plug is fitted into the charging terminal and that the charging voltage of the battery is the second voltage.

[0122] When charging the battery at a second voltage lower than the first voltage, which is the driving voltage of the electrical equipment, the motor and inverter are used to boost the voltage to the first voltage, in which case the motor generates torque. According to (1), when it is detected that the charging plug is engaged 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 in the forward and backward directions.

[0123] (2) The vehicle according to (1), wherein:

[0124] The control unit controls the current change rate to be equal to or lower than a predetermined value when charging the battery at the second voltage.

[0125] According to (2), when the movement of the vehicle in the front-rear direction is restricted by the brake mechanism, the torque of the motor will cause the vehicle to swing in the up-down direction. However, when the battery is charged at the second voltage, the movement of the vehicle can be mitigated by controlling the current change rate to be below a predetermined value.

[0126] (3) The vehicle according to (1) or (2), wherein:

[0127] A disconnecting device (sixth contactor VS / C) is provided in the power transmission path between the battery and the electrical equipment.

[0128] When the storage battery is charged at the second voltage, the power transmission between the storage battery and the electrical device is cut off by the disconnecting device.

[0129] According to (3), when the storage battery is charged at the second voltage, it is possible to prevent the second voltage from the charging device from being supplied to the electrical device driven at the first voltage.

Claims

1. A vehicle comprising: batteries; a motor, which 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 the battery is charged 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 discharged, and is driven by the first voltage boosted by the motor and the inverter when the battery is charged at a second voltage lower than the first voltage; a control unit that controls charging of the battery; as well as a braking mechanism that limits the wheel rotation, in, The control unit activates the brake mechanism when detecting that a charging plug is fitted into the charging terminal and that the charging voltage of the battery is the second voltage.

2. The vehicle according to claim 1, wherein The control unit controls the current change rate to be equal to or lower than a predetermined value when charging the battery at the second voltage.

3. The vehicle according to claim 1 or 2, wherein: A disconnecting device is provided in the power transmission path between the battery and the electrical equipment. When the storage battery is charged at the second voltage, the power transmission between the storage battery and the electrical device is cut off by the disconnecting device.

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