Vehicle

Abstract

The objective of this invention is to detect the proper connection of relays when using the output voltage of a boost circuit to drive them. The first and second relays are driven by the output voltage of a boost circuit that boosts the voltage of a battery pack used in auxiliary equipment. The boost circuit boosts voltage during the period when the boost command is ON. When the output voltage is above a threshold A, a voltage flag is set to 1. When the voltage flag is temporarily set to "1", the connection commands for the first and second relays sequentially become ON commands. When the first relay is ON and the voltage flag is 1, a counter CB is incremented; when the second relay is ON and the voltage flag is 1, a counter CG is incremented. When the voltage flag is 0, both counters CB and CG are reset. When counter CB is above a threshold T, a normal flag Fb becomes 1; when counter CG is above a threshold T, a normal flag Fg becomes 1.

Description

Technical Field

[0001] This invention relates to a vehicle. Background Technology

[0002] Japanese Patent Application Publication No. 2024-8531 (Patent Document 1) discloses a vehicle equipped with an energy storage device (battery pack). In this vehicle, a power control unit converts the DC power from the battery pack into AC power to drive a driving motor. The battery pack and the power control unit are electrically connected via a system main relay. When the system main relay is in a connected state, power can be supplied to the driving motor.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2024-8531 Summary of the Invention

[0004] Although not explicitly described in Patent Document 1, relays mounted in vehicles (system main relays) are typically driven (connected / disconnected) by an auxiliary equipment battery pack. When the operating voltage of the relay for stable operation is higher than the output voltage of the auxiliary equipment battery pack, a boost circuit is used to boost the output voltage of the auxiliary equipment battery pack to drive the relay.

[0005] The auxiliary equipment battery pack powers other devices, such as electric power steering. Therefore, during the boost phase of the boost circuit, when power from the auxiliary equipment battery pack is supplied to other devices, the output voltage of the boost circuit may sometimes drop. If the output voltage of the boost circuit drops, it may sometimes be impossible to properly connect the relay.

[0006] The purpose of this invention is to detect that the relay is properly connected when the output voltage of the boost circuit is used to drive the relay.

[0007] The vehicle of the present invention includes: a drive battery pack; a driving motor powered by electricity from the drive battery pack; a relay disposed on a power line connecting the drive battery pack and the driving motor; an auxiliary equipment battery pack; a boost circuit for boosting the voltage of the auxiliary equipment battery pack; and a control device. The relay is configured to be driven and connected by the output voltage of the boost circuit. When the relay is connected, the control device determines that the relay is properly connected if the output voltage of the boost circuit is above a predetermined value for a first predetermined time.

[0008] According to this structure, the relay is driven and connected by the output voltage of a boost circuit that boosts the voltage of the battery pack used in the auxiliary equipment. If a voltage exceeding a predetermined value is applied for a sustained period of time (a first predetermined time or more), the relay is properly connected. When the relay is connected, the control device determines that the relay is properly connected if the output voltage of the boost circuit exceeds a predetermined value for a sustained period of time. Therefore, when the relay is driven using the output voltage of the boost circuit, it is possible to detect that the relay is properly connected.

[0009] Preferably, the control device can notify the relay of a connection abnormality when it does not determine that the relay is properly connected.

[0010] According to this structure, when the control device connects the relay, if the output voltage of the boost circuit is above a specified value for a specified period of time and the connection is not determined to be normal, it will notify of a connection abnormality. The notification can be an alarm. Furthermore, the notification can store a Diagnostic Trouble Code (DTC) through diagnostics (self-diagnostic function), and during diagnostics, notify of the relay connection abnormality.

[0011] Preferably, when the control device connects the relay, it boosts the voltage of the auxiliary equipment battery pack via the boost circuit for a second predetermined time period longer than the first predetermined time. If the control device does not determine that the relay is properly connected, it may boost the voltage of the auxiliary equipment battery pack for a third predetermined time period after the second predetermined time period.

[0012] According to this structure, when the control device does not determine that the relay is properly connected, it will extend the voltage boost of the boost circuit by a third predetermined time. Because the voltage boost of the boost circuit is extended, the chance of the relay being properly connected increases. Since the voltage boost of the boost circuit is extended by the third predetermined time, excessive heating of the boost circuit can be suppressed.

[0013] Preferably, the relay includes: a first relay disposed on the positive terminal of the power line; and a second relay disposed on the negative terminal of the power line. The control device controls the circuit by connecting the first relay first and then the second relay. The control device can determine whether the first and second relays are properly connected at the end of a second predetermined time period, and if it is not determined that the relays are properly connected, it can boost the voltage of the auxiliary equipment battery pack through the boost circuit for a third predetermined time period.

[0014] According to this structure, the control device controls the circuit by connecting a first relay to the positive line and then a second relay to the negative line. At the end of a voltage boost based on a second predetermined time, the control device determines whether the first and second relays are properly connected. Then, if the control device does not determine that the relays are properly connected, it extends the voltage boost of the boost circuit for a third predetermined time. By continuing to connect multiple relays through the voltage boost during the second predetermined period, the voltage boost standby time is reduced compared to the case where voltage is boosted each time the first and second relays are connected, and heat generation is also reduced. Since the control device extends the voltage boost of the boost circuit when the relays are not properly connected, the chance of the relays being properly connected increases.

[0015] Preferably, if the control device fails to determine that the relay is properly connected within a third predetermined time period, it notifies the relay of a connection abnormality.

[0016] According to this structure, even at the end of the boost circuit's extended boost phase, if the relay is not determined to be properly connected, a connection abnormality is notified. Therefore, the reliability of connection abnormalities can be improved.

[0017] Invention Effects

[0018] According to the present invention, when the output voltage of the boost circuit is used to drive the relay, it is possible to detect that the relay is properly connected. Attached Figure Description

[0019] Figure 1 This is an overall structural diagram of the vehicle involved in the embodiments of the present invention.

[0020] Figure 2 This is a diagram illustrating the action of SMR.

[0021] Figure 3 This is a flowchart illustrating an example of boost control processing performed by the battery ECU.

[0022] Figure 4 This is a flowchart illustrating an example of a normal decision-making process performed by the battery ECU.

[0023] Figure 5 This is a flowchart illustrating the extended control process in boost control.

[0024] Figure 6 This is a timing diagram of the SMR connection. Detailed Implementation

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, identical or corresponding parts in the drawings will be labeled with the same symbols, and their descriptions will not be repeated.

[0026] Figure 1 This is an overall structural diagram of vehicle 1 according to an embodiment of the present invention. Furthermore, the following description will focus on the case where vehicle 1 is a battery electric vehicle (BEV), but the vehicle of the present invention may also be a hybrid electric vehicle (HEV) or a plug-in hybrid electric vehicle (PHEV).

[0027] refer to Figure 1 Vehicle 1 includes a battery pack 10, a power control unit (hereinafter also referred to as "Power Control Unit: PCU") 20, a motor generator (hereinafter also referred to as "Motor Generator: MG") 30, drive wheels 40, and a system main relay (SMR) 50. Furthermore, vehicle 1 includes a smoothing capacitor 55, a battery electronic control unit (Electronic Control Unit: ECU) 60, and a vehicle ECU 70.

[0028] Battery pack 10 is a rechargeable power storage element. Battery pack 10 is a group of batteries, for example, composed of secondary batteries such as lithium-ion batteries or nickel-metal hydride batteries. Battery pack 10 is configured to be charged by a charging device not shown (external charging). Furthermore, battery pack 10 is an example of the drive battery pack of the present invention.

[0029] The battery pack 10 stores the power needed to drive the MG30 and can supply power to the MG30 via the PCU20. Furthermore, the battery pack 10 is charged by receiving generated power through the PCU20 when the MG30 is generating electricity.

[0030] PCU20 performs bidirectional power conversion between battery pack 10 and MG30 based on control signals from battery ECU60 or vehicle ECU70. PCU20 is configured, for example, to include an inverter that drives MG30 and a converter that boosts the DC voltage supplied to the inverter to a level higher than the output voltage of battery pack 10.

[0031] MG30 is, for example, a three-phase AC synchronous motor with permanent magnets embedded in its rotor. MG30 is driven by PCU20 to generate rotational driving force, which is transmitted to the drive wheel 40. On the other hand, when the vehicle 1 brakes or when acceleration decreases on a downhill slope, MG30 operates as a generator to regenerate electricity. The electricity generated by MG30 is supplied to the battery pack 10 via PCU20. MG30 is equivalent to the "driving motor" of this invention.

[0032] A smoothing capacitor 55 is electrically connected between the positive line PL and the negative line NL to smooth the AC component of voltage fluctuations between the positive line PL and the negative line NL. Alternatively, the smoothing capacitor 55 may be included in the PCU20.

[0033] SMR50 includes relays SMRB, SMRG, SMRP, and current-limiting resistor 52. Relay SMRB is connected to the positive terminal of battery pack 10 and the positive terminal PL of PCU20. Relay SMRG is connected to the negative terminal of battery pack 10 and the negative terminal NL of PCU20. Relay SMRP and current-limiting resistor 52 are connected in series and in parallel with relay SMRG. Relay SMRB corresponds to the "first relay" of this invention, and relay SMRG corresponds to the "second relay" of this invention.

[0034] In this embodiment, each relay is a mechanical relay that closes its contacts by moving a movable contact through the electromagnetic force of an electromagnetically supplied solenoid (coil). Alternatively, a contactless relay (semiconductor relay) can be used for the SMRP relay. Each relay is turned on / off in response to a control signal from the battery ECU60.

[0035] The relay SMRP and the current-limiting resistor 52 form a pre-charging circuit to mitigate the inrush current flowing when SMR50 is turned on. Specifically, when SMR50 is turned on, after relay SMRB is turned on and before relay SMRG is turned on, relay SMRP is turned on, and while the current is limited by the current-limiting resistor 52, the smoothing capacitor 55 is pre-charged (pre-charged). Thus, the inrush current flowing from the battery pack 10 to the smoothing capacitor 55 when SMR50 is turned on is mitigated.

[0036] An auxiliary equipment battery pack 100 is connected to the positive terminal PL and the negative terminal NL via a DC / DC converter 80. The auxiliary equipment battery pack 100 serves as a power source for auxiliary equipment 200 of the vehicle 1, such as electric power steering. In this embodiment, the output voltage (rated voltage) of the auxiliary equipment battery pack 100 is 12V. The DC / DC converter 80 charges the auxiliary equipment battery pack 100 with power from the battery pack 10. The battery ECU 60 controls the DC / DC converter 80 to maintain the state of charge (SOC) of the auxiliary equipment battery pack 100 within a specified range.

[0037] The output voltage of the auxiliary equipment battery pack 100 is boosted by the boost circuit 90. Relays SMRB and SMRG are driven by applying (energizing) the output voltage of the boost circuit 90. Relay SMRP is driven by applying (energizing) the output voltage of the auxiliary equipment battery pack 100. Semiconductor switches (Intelligent Power Devices, IPDs) 60 are provided between the boost circuit 90 and relays SMRB and SMRG, and between the auxiliary equipment battery pack 100 and relay SMRP. When the corresponding IPD 60 is turned on, relays SMRB, SMRG, and SMRP are energized.

[0038] Both the battery ECU 60 and the vehicle ECU 70 consist of a central processing unit (CPU), memory (read-only memory (ROM) and random access memory (RAM)), and input / output ports for inputting / outputting various signals (neither is shown in the figure). The battery ECU 60 and the vehicle ECU 70 can communicate with each other, for example, via a controller area network (CAN).

[0039] If a power switch (start switch) (not shown) is turned on, the vehicle ECU 70 executes a process to set the vehicle 1 to the Ready-ON state (start process). In this process, the battery ECU 60 receives a command from the vehicle ECU 70 to set the SMR 50 to the ON state. Conversely, if the power switch is turned off, the vehicle ECU 70 executes a process to set the vehicle 1 to the Ready-OFF state (stop process). In this process, the battery ECU 60 receives a command from the vehicle ECU 70 to set the SMR 50 to the OFF state. The battery ECU 60 and the vehicle ECU 70 represent an example of the "control device" of the present invention.

[0040] Figure 2 This is a diagram illustrating the operation of the SMB relay. Figure 2 In the diagram, the vertical axis represents the force acting on the movable iron core r1, and the horizontal axis represents the stroke of the movable iron core r1. If the solenoid (coil) r2 is energized, the movable iron core r1 is attracted to the fixed iron core r3 by the magnetic field generated by the solenoid r2. The attractive force of the movable iron core r1 is approximately proportional to the magnitude of the voltage (current) applied to the solenoid r2, and approximately inversely proportional to the square of the distance between the movable iron core r1 and the fixed iron core r3.

[0041] refer to Figure 2If a voltage is applied to the solenoid r2 of the relay SMB, the movable iron core r1 generates an attractive force exceeding the preload force F1 (and static friction) of the return spring s1, causing the movable contact mc to move from the off state (A) to the contact state (B). In the contact state (B), the movable contact mc contacts the fixed contacts fc and fc, and the relay SMB becomes connected. If the voltage applied to the solenoid r2 is sufficiently high, such as... Figure 2 As shown by the dashed line, the attractive force of the movable iron core r1 becomes greater than the sum of the reaction force of the return spring s1 and the preload force F2 of the compression spring s2, causing the movable iron core r1 to move to the fully connected state (C). In the fully connected state (C), the movable iron core r1 abuts against the fixed iron core r3, and the compression spring s2 is compressed, as shown... Figure 2 As shown by the solid line, the reaction force applied to the movable iron core r1 is the sum of the reaction force of the return spring s1 and the reaction force of the compression spring s2, F3. After the relay SMRB is in the fully connected state (C), the voltage applied to the solenoid r2 can be reduced to a voltage at which the attractive force of the movable iron core r1 can maintain a value of F3.

[0042] When the voltage applied to solenoid r2 is low, such as Figure 2 As shown by the dashed line, the attractive force of the movable iron core r1 is sometimes less than the sum of the reaction force of the return spring s1 and the preload force of the compression spring s2, F2, in the contact contact state (B). In this case, the movable iron core r1 stops in the contact contact state (B). When the movable iron core r1 stops in the contact contact state (B), even if the energization of the solenoid r2 is stopped, the movable iron core r1 will not move due to friction or other forces because the reaction force of the return spring s1 is small, and sometimes it will not be in the cut-off state (A).

[0043] The SMRG and SMRB relays have the same structure and operation. The SMRP relay also has the same structure, but compared to the SMRB relay, the SMRP relay is smaller in size, and its movable core can move to the fully connected state even when the voltage applied to the solenoid is low.

[0044] In this embodiment, when relays SMB and SMRG are connected, if the output voltage of the boost circuit 90 remains above a specified value for a specified time, it is determined that relays SMB and SMRG are properly connected. Thus, it is detected that relays SMB and SMRG are properly connected.

[0045] Figure 3This is a flowchart illustrating an example of the boost control process performed by the battery ECU 60. The flowchart begins when a power switch (not shown) is turned on to initiate the vehicle 1 startup process, and repeats this process at predetermined intervals. It then ends either when the boost control in step 15 (hereinafter referred to as "S") is stopped, or when the extended control in step S19 ends. Additionally, this process is also performed when external charging of the battery pack 10 begins, provided that the SMR 50 is connected during external charging of the battery pack 10.

[0046] First, in S10, it is determined whether the boost command is ON. During the vehicle 1 start-up process, in order to connect SMR50, a boost command and an ON command for SMR50 are output from the vehicle ECU70. If a boost command is output from the vehicle ECU70, the boost command becomes ON. If the boost command is ON, the determination is affirmative in S10 and proceeds to S11. If the boost command is OFF, the determination is negative in S10 and proceeds to S14.

[0047] In S11, the battery ECU 60 activates the boost circuit 90 to boost the output voltage of the auxiliary equipment battery pack 100. In the subsequent S12, it is determined whether the output voltage Vd of the boost circuit 90 is above a threshold A. The output voltage Vd can be determined by a voltage sensor 5 (see reference 5) located on the output side of the boost circuit 90. Figure 1 The threshold A is the voltage required to drive relays SMB and SMRG to a fully connected state. For example, threshold A can be 14 [V]. Threshold A is equivalent to the "prescribed value" of this invention. If the output voltage Vd exceeds threshold A, a positive determination is made in S12 and proceeds to S13. If the output voltage Vd is less than threshold A, a negative determination is made and proceeds to S16.

[0048] In S13, the voltage flag Fv is set to 1, and the current routine ends. In S16, the voltage flag Fv is set to 0, and the current routine ends.

[0049] In S14, it is determined whether the boost command has switched from ON to OFF. After the vehicle ECU 70 outputs the boost command, if a set time has elapsed, the output of the boost command stops. If the output of the boost command stops, the boost command becomes OFF. Within the set time, the boost command becomes ON. The set time includes the pre-charging period based on the relay SMRP, which is the time required to connect the SMR50 (relays SMRB, SMRP, SMRG), and is set through prior experiments, etc. The set time is equivalent to the "second specified time" of this invention.

[0050] In this process, if the boost instruction switches from ON to OFF, a positive check is performed in S14 and the process proceeds to S17. If the boost instruction is OFF (in the case where the boost instruction switched from ON to OFF before the previous process), a negative check is performed and the process proceeds to S15.

[0051] In S17, it is determined whether the connection of relays SMB and SMRG is normal. Whether the connection is normal is determined through the normal judgment process described later (see reference). Figure 4 The determination is made using the normal flags Fb and Fg set in step S17. Normal flag Fb is set to 1 when the connection of relay SMB is normal, and to 0 when there is an abnormality. Normal flag Fg is set to 1 when the connection of relay SMB is normal, and to 0 when there is an abnormality. In step S17, if both normal flags Fb and Fg are 1, a positive determination is made and the process proceeds to step S15. If at least one of normal flags Fb and Fg is 0, a negative determination is made and the process proceeds to step S18.

[0052] In S15, after stopping the operation of the boost circuit 90 and thus stopping the boost, proceed to S16. In S18, after performing a false alarm handling, proceed to S19. The false alarm handling notifies the vehicle ECU 70 to execute the extended control of S19. The vehicle ECU 70 receives this notification and may, for example, display "System startup processing" on the display of the Human Machine Interface (HMI) device 71.

[0053] In S19, the battery ECU60 performs extended control ( Figure 5 Then, if the extended control ends, the current routine ends. Details regarding extended control will be described later.

[0054] Figure 4 This is a flowchart illustrating an example of the normal judgment process performed by the battery ECU60. This flowchart demonstrates the execution of... Figure 3 During boost control, the process is repeated at each specified interval. This normal judgment process is performed on both relay SMB and relay SMRG. Since the process is the same, it is performed on relay SMRG.

[0055] In S20, the battery ECU60 determines whether relay SMRG is ON. During the startup process, after the boost circuit 90 operates, if the voltage flag Fv is temporarily set to "1", the battery ECU60 outputs an ON command in the order of relays SMB, SMRP, and SMRG. Following the ON command, the battery ECU60 sequentially connects the corresponding IPD60, energizing relays SMB, SMRP, and SMRG in that order. Additionally, if a power switch (not shown) is disconnected, the vehicle ECU70 outputs an OFF command (cut-off command) for SMR50 to the battery ECU60. If the battery ECU60 receives the OFF command for SMR50, it sets all IPD60 to OFF, cutting off the energization to relays SMB, SMRP, and SMRG, thus putting SMR50 in the off state.

[0056] If the output voltage of the boost circuit 90 is applied to the relay SMRG and the relay SMRG is ON, a positive determination is made in S20 and the process proceeds to S21. If the relay SMRG is OFF (not energized), a negative determination is made and the process proceeds to S26. Furthermore, the determination of whether the relay SMRG is ON can be based on the ON command of the relay SMRG, or the response delay of the relay SMRG can be considered, determining ON after a constant time has elapsed after the ON command is output.

[0057] In S21, the battery ECU60 determines whether the voltage flag Fv is 1. If the voltage flag Fv is 1, the determination is affirmative and proceeds to S22; if the voltage flag Fv is 0, the determination is negative and proceeds to S27.

[0058] In S22, the battery ECU60 determines whether the normal flag Fg is 1. The normal flag Fg is set to 1 in the processing of S25 described later. If the normal flag Fg is 0, the determination is denied and proceeds to S23. If the normal flag Fg is 1, the determination is affirmed and the current routine ends.

[0059] In S23, after incrementing the counter CG, proceed to S24. In S24, determine whether the counter CG is above the threshold T. If the counter CG is above the threshold T, affirmatively determine and proceed to S25. When the relay SMRG is ON, if the voltage flag Fv is 1 (the output voltage Vd of the boost circuit 90 is above the threshold A) for a duration equivalent to the threshold T, then affirmatively determine in S24 and proceed to S25. The threshold T is a value equivalent to the "first predetermined time" of this invention. If the counter CG is less than the threshold T, negatively determine and end this routine procedure.

[0060] In S25, after setting the normal flag Fg to 1, the current routine ends. In S26, it is determined whether the normal flag Fg is 1. If the normal flag Fg is 1, the determination is affirmative and the current routine ends. If the normal flag Fg is 0, the determination is negative and proceeds to S27.

[0061] In S27, the normal flag Fg is set to 0 (and remains at 0 if it is already 0), and the counter CG is reset to 0 before the current routine ends.

[0062] Figure 3 The normal decision-making process is performed on the relay SMB in the same way. In the normal decision-making process for the relay SMB, such as... Figure 3 As shown in the table, “relay SMRG” in S20 is replaced with “relay SMRB”, “Fg” in S22, 25, 26, and 27 is replaced with “Fb”, and “counter CG” in S23, 24, and 27 is replaced with “counter CB”.

[0063] In the normal determination process, when relay SMRG is ON, if the voltage flag Fv is 1 (the output voltage Vd of boost circuit 90 is above threshold A) for a duration equivalent to threshold T, then in S25, the normal flag Fg is set to 1. Furthermore, when relay SMRB is ON, if the voltage flag Fv is 1 (the output voltage Vd of boost circuit 90 is above threshold A) for a duration equivalent to threshold T, then in S25, the normal flag Fb is set to 1.

[0064] Figure 5 It indicates boost control ( Figure 3 The flowchart describes the processing of the extended control (S19) in the battery ECU 60. First, after starting timer E in S190, the process proceeds to S191. In S191, it is determined whether timer E is above a threshold eT. The threshold eT corresponds to the "third predetermined time" of this invention. If timer E is less than the threshold eT, the determination is denied and the process proceeds to S192. If timer E is above the threshold eT, the determination is affirmative and the process proceeds to S196.

[0065] In S192, the boost circuit 90 continues its boost operation, and the process proceeds to S193. In S193, it is determined whether the output voltage Vd of the boost circuit 90 is above the threshold A. If the output voltage Vd is above the threshold A, the process is affirmative, and the process proceeds to S194, where the voltage flag Fv is set to 1, and the process returns to S191. If the output voltage Vd is below the threshold A, the process is negated, and the process proceeds to S195, where the voltage flag Fv is set to 0, and the process returns to S191.

[0066] In S196, the boost circuit 90 is stopped, and the process proceeds to S197. In S197, it is determined whether the connections of relays SMB and SMRG are normal. Whether the connections are normal is related to S17 (…). Figure 3 Similarly, through normal decision processing (refer to...) Figure 4 The determination is made using the normal flags Fb and Fg set in (). If both normal flags Fb and Fg are 1, a positive determination is made and the process proceeds to S199. If at least one of the normal flags Fb and Fg is 0, a negative determination is made and the process proceeds to S198.

[0067] In S198, an anomaly is handled. The anomaly handling process notifies the vehicle ECU 70 that the SMR 50 cannot connect properly. Upon receiving this notification, the vehicle ECU 70 displays, for example, "SMR Anomaly" on the display of the Human Machine Interface (HMI) device 71. Furthermore, the vehicle ECU 70 illuminates the Malfunction Indicator Lamp (MIL) 72 and writes a diagnostic diagnostic test (DTC) to its memory. The DTC can be a code identifying the relay that caused the anomaly (failure to connect properly).

[0068] In S199, a false alarm is triggered. The false alarm stops the connection of SMR50 from the battery ECU60 to the vehicle ECU70. Upon receiving this notification, the vehicle ECU70 stops displaying messages such as "System startup in progress" on the HMI71.

[0069] Figure 6 This is a timing diagram for the connection of SMR50. If the power switch (start switch) not shown is turned on, the startup process begins. At time t0, the boost command changes from OFF to ON. If the boost command becomes ON, the boost circuit 90 operates, and the output voltage Vd rises. At time t1, the output voltage Vd exceeds the threshold A, and the voltage flag Fv is set to 1. If the voltage flag Fv is temporarily set to "1", the command to connect relays SMB, SMBR, and SMBR in that order becomes ON. If the command to relay SMB changes from OFF to ON, after a response delay, relay SMB becomes ON at time t2, and the counter CB begins counting. At time t3, if the counter CB exceeds the threshold T, the normal flag Fb is set to 1. The period from time t2 to time t3 corresponds to the "first specified time" of this invention.

[0070] Next, before the instruction for relay SMRG changes from OFF to ON, the instruction for relay SMRP changes from OFF to ON. By turning relay SMRP ON, the smoothing capacitor 55 is pre-charged; after relay SMRG becomes ON, relay SMRP becomes OFF.

[0071] Then, at time t4, the instruction to relay SMRG changes from OFF to ON. After a response delay, relay SMRG becomes ON at time t5, and counter CG begins counting. For example, if auxiliary device 200 consumes power from auxiliary device battery pack 100, at time t6, if the output voltage Vd of boost circuit 90 is less than threshold A, then voltage flag Fv is set to 0. If voltage flag Fv is set to 0, counter CG is reset to 0.

[0072] Then, at time t7, if the output voltage Vd of the boost circuit 90 becomes above the threshold A, the voltage flag Fv is set to 1, and the counter CG is restarted. At time t8, according to the instruction from the vehicle ECU 70, the boost command changes from ON to OFF. The period from time t0 to time t8 corresponds to the "second specified time" of the present invention. At time t8, the counter CG is less than the threshold T, so extended control is performed. Extended control is control that maintains the boost of the boost circuit 90 without stopping even if the boost command is OFF. In this embodiment, from time t8 to time t10, the boost of the output voltage of the auxiliary device battery pack 100 based on the boost circuit 90 is extended. Then, at time t9, the counter CG becomes above the threshold T, and the normal flag Fg is set to 1. At time t10, the boost of the boost circuit 90 stops. The period from time t8 to time t10 corresponds to the threshold eT (S191).

[0073] According to this embodiment, the relay SMB, located on the positive terminal of the power line, and the relay SMRG, located on the negative terminal of the power line, are driven and connected by the output voltage Vd of the boost circuit 90, which boosts the voltage of the auxiliary equipment battery pack 100. The boost circuit 90 boosts the voltage of the auxiliary equipment battery pack 100 from time t0 to time t8 (a second predetermined time). The battery ECU 60 connects the relay SMB and the relay SMRG in this order. When connecting the relay SMB, if the output voltage Vd of the boost circuit 90 is above threshold A for a first predetermined time (when the counter CB is above threshold T), the battery ECU 60 determines that the relay SMB is properly connected. When connecting the relay SMRG, if the output voltage Vd of the boost circuit 90 is above threshold A for a first predetermined time (when the counter CG is above threshold T), the battery ECU 60 determines that the relay SMRG is properly connected. Therefore, when the output voltage of the boost circuit 90 is used to drive the relay, it is possible to detect that the relay is properly connected.

[0074] According to this embodiment, at time t8 (the end of the boost command based on the second predetermined time), the battery ECU 60 determines whether relays SMB and SMRG are properly connected. Then, if the battery ECU 60 does not determine that the relays are properly connected, it extends the boost of the boost circuit 90 until timer E reaches the threshold eT (within the third predetermined time). By continuing to connect multiple relays through the boost from time t0 to time t8 (the second predetermined time), the boost standby time of the boost circuit 90 can be reduced compared to the case where the boost circuit 90 operates every time relays SMB and SMRG receive an ON command, and heat generation can be reduced. Furthermore, by extending the boost of the boost circuit 90 until timer E reaches the threshold eT when the relays are not properly connected, the chance of the relays being properly connected is increased.

[0075] In the above embodiment, at the moment t8 when the boost command changes from ON to OFF (based on the end of the boost at the second predetermined time), the battery ECU60 performs extended control without determining that relays SMB and SMRG are properly connected. Figure 3 (In S17, when a positive determination is made, the extended control of S19 is handled). However, the extended control can also be omitted. In this case, S18 ( Figure 3 The "false anomaly handling" in S198 can be replaced with S198. Figure 5 "Exception handling".

[0076] In the above implementation, it was determined whether relays SMB and SMRG were properly connected. However, it is also possible to determine whether only relay SMRG, which is connected later, is properly connected. (Alternatively, the determination of relay SMB may not be performed.) When the connection command for relay SMRG changes from OFF to ON, relay SMB has already changed to ON. Therefore, if relay SMRG is properly connected, there is a high probability that relay SMB is also properly connected.

[0077] In the above embodiment, the relay SMRP can be driven by the output voltage of the boost circuit 90. In this case, the relay SMRP can also determine whether it is properly connected, just like the relays SMRB and SMRG.

[0078] The embodiments disclosed herein are considered illustrative in all respects and not restrictive. The scope of the invention is defined not by the description of the above embodiments but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0079] Symbol Explanation

[0080] 1-Vehicle, 5-Voltage sensor, 6-IPD, 10-Battery pack, 20-PCU, 30-MG, 40-Drive wheel, 50-SMR, SMRB, SMRP, SMRG-Relay, 52-Current limiting resistor, 55-Smoothing capacitor, 60-Battery ECU, 70-Vehicle ECU, 71-HMI device, 72-MIL, 80-DC / DC converter, 90-Boost circuit, 100-Battery pack for auxiliary equipment, 200-Auxiliary equipment, fc-Fixed contact, mc-Modible contact, NL-Negative wire, PL-Positive wire, r1-Modible iron core, r2-Solenoid (coil), r3-Fixed iron core, s1-Reset spring, s2-Crimping spring.

Claims

1. A vehicle, comprising: Battery pack for driving; A driving motor, which is powered by the drive battery pack; A relay is provided on the power line connecting the drive battery pack and the driving motor; Battery packs for auxiliary equipment; A boost circuit that boosts the voltage of the battery pack used in the auxiliary equipment; and Control device, The vehicle is characterized in that... The relay is configured to be driven and connected by the output voltage of the boost circuit. When the control device connects the relay, if the output voltage of the boost circuit remains above a specified value for a first specified time, it determines that the relay is normally connected.

2. The vehicle according to claim 1, characterized in that, If the control device does not determine that the relay is properly connected, it will notify the relay of a connection error.

3. The vehicle according to claim 1, characterized in that, The control device performs the following processing: When the relay is connected, the voltage of the auxiliary equipment battery pack is boosted by the boost circuit during a second predetermined time that is longer than the first predetermined time. and If the relay is not determined to be properly connected, the voltage of the auxiliary equipment battery pack is boosted by the boost circuit during a third specified time period after the second specified time period.

4. The vehicle according to claim 3, characterized in that, The relay includes: A first relay, which is located on the positive terminal of the power line; and The second relay is located on the negative terminal of the power line. The control device performs the following processing: Control is performed by connecting the first relay first and then connecting the second relay; At the end of the second specified time, it is determined whether the first relay and the second relay are properly connected; and If the relay is not determined to be properly connected, the voltage of the auxiliary equipment battery pack is boosted through the boost circuit during the third predetermined time period.

5. The vehicle according to claim 3 or 4, characterized in that, If the control device fails to determine that the relay is properly connected within the third specified time period, it notifies the relay of a connection abnormality.

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