JP2020156247A - Control device for on-vehicle power supply system - Google Patents

Abstract

To provide a control device for an on-vehicle power supply system that can take proper measures without letting a driver feel incompatible if fixation abnormality occurs to a switch which electrically changes electric connections between a rotary electric machine and a storage battery.SOLUTION: A battery control part 31 which constitutes an on-vehicle power supply system 100 turns ON one of switches SW1, SW2, and then determines, when a rotary electric machine 11 is being driven, whether or not fixation abnormality occurs to the switch which is in the ON state out of those switches. On determining that the fixation abnormality occurs, the switch in an OFF state out of the switches SW1, SW2 is turned ON. A rotary electric machine control part 13 continues to drive the rotary electric machine 11 with restriction in a drive request period of the rotary electric machine 11.SELECTED DRAWING: Figure 1

Description

The present invention relates to a control device for an in-vehicle power supply system mounted on a vehicle.

Conventionally, there is an in-vehicle power supply system described in Patent Document 1. This in-vehicle power supply system includes a first storage battery, a second storage battery, a rotary electric machine, and a switch for switching an electrical connection between the second storage battery and the rotary electric machine. In the in-vehicle power supply system, when a switch sticking abnormality is detected, the power running of the rotating electric machine is prohibited in order to prevent a drop in the voltage between the terminals of the second storage battery due to the power running of the rotating electric machine.

Japanese Patent No. 5930041

In the in-vehicle power supply system, a sticking abnormality may occur in the switch being operated in the ON state while the rotary electric machine is being driven. In such a case, in the invention disclosed in Patent Document 1, the rotary electric machine is being driven. However, the drive is forcibly stopped. For example, when the rotary electric machine assists the output of the engine by its drive, the assist to the output of the engine by the rotary electric machine is stopped due to a sticking abnormality in the switch being operated in the ON state. Therefore, there is a concern that the driver may feel uncomfortable due to the drive stop of the rotary electric machine due to the sticking abnormality.

The present invention has been made in view of the above problems, and when a sticking abnormality occurs in the switch for switching the electrical connection between the rotary electric machine and the storage battery, appropriate measures are taken without causing discomfort to the driver. It is an object of the present invention to provide a control device for an in-vehicle power supply system capable of performing.

In order to solve the above problems, the first invention relates to a rotary electric machine, a first storage battery and a second storage battery connected in parallel to the rotary electric machine, and electricity between the rotary electric machine and the first storage battery. It is applied to an in-vehicle power supply system including a first switch for switching an electrical connection and a second switch for switching an electrical connection between the rotary electric machine and the second storage battery, and is applied to power running and power generation of the rotary electric machine. The present invention relates to a control device that operates at least one of the first switch and the second switch in an ON state when driving any of the switches. When the control device operates either the first switch or the second switch in the on state and drives the rotary electric machine, a sticking abnormality occurs in the switch in the on state among the switches. The abnormality determination unit that determines whether or not there is, and when it is determined that the sticking abnormality has occurred, the first switch and the second switch are turned off within the drive request period of the rotary electric machine at that time. It is provided with a fail-safe control unit that operates the state switch to the on state and continues while limiting the drive of the rotary electric machine.

If it is determined that a sticking abnormality has occurred in the switch that is being turned on while the rotary electric machine is being driven, if the drive of the rotary electric machine is stopped at that time, there is a concern that the driver may feel uncomfortable. In addition, even if the rotary electric machine is continuously driven, the switch determined to have a sticking abnormality is in an unstable state, and it is considered that the switch may temporarily switch from the on state to the off state, and rotates. There is concern that the electrical connection between the electric machine and each storage battery will be cut off. In this case, for example, in a situation where power is supplied from the first and second storage batteries to the rotary electric machine, there is a concern that the driving of the rotary electric machine may be inconvenient and the driver may feel uncomfortable. In the above configuration, it is determined whether or not a sticking abnormality has occurred in the on-operation switch of the first switch or the second switch while the rotary electric machine is being driven. When it is determined that a sticking abnormality has occurred in the switch being turned on, the off state switch of the first switch and the second switch is operated to the on state during the drive request period of the rotary electric machine at that time. At the same time, the drive of the rotary electric machine is continued in a restricted state. As a result, even if a sticking abnormality occurs in the switch being operated in the on state, the rotary electric machine and the storage battery can be electrically connected by a switch other than this switch, so that the driver can connect the in-vehicle power supply system. Appropriate measures can be taken without causing discomfort.

In the second invention, the fail-safe control unit finishes driving the rotary electric machine within the drive request period determined by the abnormality determination unit to cause the sticking abnormality, and then rotates after that. Prohibit the driving of electric machines.

In the above configuration, the drive of the rotary electric machine is prohibited after the drive of the rotary electric machine is restricted and continued due to the abnormal sticking of the switch during operation in the on state. As a result, it is possible to prevent the rotary electric machine from being driven again in a state where the switch during the ON operation has a sticking abnormality, and it is possible to take appropriate measures for the rotary electric machine.

In the third invention, the second storage battery is a lithium ion storage battery, the first storage battery is a lead storage battery, and the fail-safe control unit determines that a sticking abnormality has occurred in the second switch. When the first switch is operated in the ON state, the drive of the rotary electric machine is restricted and continued so that the voltage between the terminals of the second storage battery falls within a predetermined output voltage range.

Lithium-ion storage batteries have less power loss during charging and discharging than lead-acid batteries, and can be charged and discharged with high efficiency. However, the lithium ion storage battery has a problem that deterioration is more likely to be promoted by overcharging and overdischarging than the lead storage battery. In the above configuration, when power running or regenerative power generation of a rotary electric machine is continued in a state where a sticking abnormality occurs in the second switch being operated in the ON state, the voltage between terminals of the lithium ion storage battery, which is the second storage battery, is output as a predetermined value. It is prevented from going out of the voltage range. As a result, it is possible to continue driving the rotary electric machine while suppressing deterioration of the second storage battery.

In the fourth invention, the vehicle-mounted power supply system includes a third switch provided in a bypass path for connecting the rotary electric machine and the first storage battery without going through the first switch, and the bypass path includes a third switch. A fusing portion is provided that is fusing when a current larger than a predetermined fusing current flows, and the fail-safe control unit is said to be the first when it is determined that a sticking abnormality has occurred in the second switch. While operating the 1 switch in the on state, when it is determined that a sticking abnormality has occurred in the 1st switch, the 3rd switch is operated in the on state and the current flowing in the bypass path is the fusing current. The drive of the rotary electric machine is continued while being controlled so as to be smaller than.

When a sticking abnormality occurs in the first switch that is being operated in the on state, by operating the third switch in the on state, the first storage battery and the rotary electric machine can be connected via the bypass path without going through the first switch. The electrical connection between them can be continued. Here, when the rotary electric machine and the first storage battery are electrically connected via the bypass path, there is a concern that the rotary electric machine cannot be continuously driven due to the fusing portion provided in the bypass path. To. In the above configuration, when the rotating electric machine and the first storage battery are electrically connected via the bypass path by operating the third switch in the ON state, the current flowing in the bypass path is larger than the fusing current. The drive of the rotary electric machine is restricted so that it becomes smaller. As a result, when a sticking abnormality occurs in the first switch that is being operated in the ON state, the driving of the rotary electric machine is stably continued while continuing the electrical connection between the first storage battery and the rotary electric machine. be able to.

Configuration diagram of the in-vehicle power supply system. The figure explaining the fail-safe control with respect to the sticking abnormality of a switch SW2. The figure explaining the fail-safe control with respect to the sticking abnormality of a switch SW1. A flowchart illustrating fail-safe control by the battery control unit. A flowchart illustrating fail-safe control by the drive control unit. A timing chart that illustrates fail-safe control. A timing chart that illustrates fail-safe control.

Hereinafter, embodiments embodying the in-vehicle power supply system of the present invention will be described with reference to the drawings. The in-vehicle power supply system is a system that supplies electric power to a load mounted on a vehicle.

As shown in FIG. 1, the in-vehicle power supply system 100 includes a rotary electric power unit 10, a lead storage battery 20 which is a first storage battery, and a lithium ion storage battery 30 (hereinafter, referred to as Li storage battery) which is a second storage battery. It supplies power to the loads 42 and 43. In the in-vehicle power supply system 100, the Li storage battery 30 is provided in the battery unit 40. The lead storage battery 20 and the Li storage battery 30 are connected in parallel to the rotary electric machine unit 10.

The electric load 43 includes a constant voltage required load in which the voltage supplied from the vehicle-mounted power supply system 100 is required to fluctuate within a constant or at least a predetermined range. On the other hand, the electric load 42 is a general electric load other than the constant voltage required load. Further, it can be said that the electric load 43 is a load to which power failure is not allowed, and the electric load 42 is a load to which power failure is allowed as compared with the electric load 43.

Specific examples of the electric load 43, which is a constant voltage required load, are a navigation device, an audio device, a meter device, and various ECUs of a higher-level ECU. In this case, by suppressing the voltage fluctuation of the supplied power, unnecessary resets and the like are suppressed in each of the above devices, and stable operation can be realized. The electric load 43 may include a traveling system actuator such as an electric steering device or a braking device. Further, specific examples of the electric load 42 include a seat heater, a heater for a defroster of a rear window, a headlight, a wiper of a front window, a blower fan of an air conditioner, and the like.

The lead storage battery 20 is a well-known general-purpose storage battery. On the other hand, the Li storage battery 30 is a high-density storage battery having a smaller power loss during charging / discharging and a higher output density and energy density than the lead storage battery 20. The Li storage battery 30 is preferably a storage battery having higher energy efficiency during charging / discharging than the lead storage battery 20. Further, the Li storage battery 30 is configured as an assembled battery each having a plurality of single batteries. The rated voltage of each of these storage batteries 20 and 30 is the same, for example, 12V.

The rotary electric machine unit 10 is a rotary electric machine control which controls the drive of the rotary electric machine 11 which is a three-phase AC motor, an inverter 12 connected to each phase winding of the rotary electric machine 11, and an energization control of the inverter 12. It is provided with a unit 13. The rotary electric machine unit 10 is a generator with a motor function, and is configured as an ISG (Integrated Starter Generator) integrated with mechanical and electrical functions. The rotary electric machine 11 is driven and connected to the output shaft (crankshaft) of an engine (not shown) by a connecting member composed of a belt and a pulley, and the rotation is transmitted between the rotary electric machine 11 and the engine. The rotary electric machine unit 10 has a power generation function of generating electricity by rotating an engine output shaft or an axle, and a power running function of applying a rotational force to the engine output shaft.

The rotary electric machine 11 is a multi-phase winding type AC motor, and in the present embodiment, it is a three-phase AC motor. The inverter 12 is configured as a power conversion unit having a plurality of semiconductor switching elements. The inverter 12 converts a direct current into a three-phase alternating current during power running, and drives the rotary electric machine 11 by the three-phase alternating current. Further, the inverter 12 converts the three-phase alternating current output from the rotary electric machine 11 into a direct current at the time of power generation, and supplies the direct current to the storage batteries 20 and 30. As a result, the storage batteries 20 and 30 are charged.

The rotary electric machine control unit 13 is composed of a microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like. The rotary electric machine control unit 13 controls the on / off of the switching element of each phase of the inverter 12 according to the energization phase, and controls the energization current by adjusting the on / off ratio (for example, duty ratio) when the each phase coil is energized. .. Specifically, the rotary electric machine control unit 13 operates the inverter 12 on and off in order to control the power running torque T1r of the rotary electric machine 11 to the power running torque target value T1 * during power running. At the time of regenerative power generation, the rotary electric machine control unit 13 operates the inverter 12 on and off in order to control the regenerative torque T2r of the rotary electric machine 11 to the regenerative torque target value T2 *.

The battery unit 40 has terminals P1, P2, and P3, of which a lead storage battery 20 and an electric load 42 are connected in parallel to the terminal P1, a rotary electric machine unit 10 is connected to the terminal P2, and electricity is connected to the terminal P3. The load 43 is connected.

The battery unit 40 is provided with a first electric path L1 for connecting the terminal P1 and the Li storage battery 30 as an electric path in the unit. The first electric path L1 is connected to the terminal P2 at a connection point N1 which is an intermediate point.

A switch SW1 capable of switching the electrical connection between the rotary electric machine 11 and the lead storage battery 20 through the first electric path L1 is provided between the connection point N1 and the terminal P1 in the first electric path L1. There is. Further, in the first electric path L1, between the connection point N1 and the Li storage battery 30, a switch capable of switching the electrical connection between the rotary electric machine 11 and the Li storage battery 30 through the first electric path L1. SW2 is provided. In this embodiment, the switches SW1 and SW2 are normally open switches.

The battery unit 40 is provided with a second electric path L2 for connecting the connection point N3 between the terminal P1 and the switch SW1 and the connection point N4 between the switch SW2 and the Li storage battery 30 as an electric path in the unit. ing. A terminal P3 is connected to a connection point N2, which is an intermediate point of the second electric path L2. In the second electric path L2, the switch SW3 is provided between the connection point N2 and the connection point N3, and the switch SW4 is provided between the connection point N2 and the connection point N4.

The second electric path L2 is a small current path (that is, a small current path having a smaller allowable current than the first electric path L1) on the assumption that a smaller current flows than the first electric path L1 side. The electric load 43 is energized from the storage batteries 20 and 30 via the path.

Further, the battery unit 40 is provided with a bypass path L3 for connecting the lead storage battery 20 and the rotary electric machine 11 without going through the switch SW1. Specifically, the first end of the bypass path L3 is connected to the connection point N1 between the terminal P2 and the switch SW1 in the first electric path L1, and the second end is lead outside the battery unit 40. It is connected to an electric circuit connected to the positive electrode terminal of the storage battery 20. The bypass path L3 is provided with a normally closed switch SW5 and a fuse 50 as a blown portion. In this embodiment, the fuse 50 is provided outside the battery unit 40 in the bypass path L3.

The battery unit 40 includes a battery control unit 31 that turns on and off the switches SW1 to SW5. The battery control unit 31 is composed of a microcomputer including a CPU, ROM, RAM, an input / output interface, and the like. The battery control unit 31 operates the on / off of the switches SW1 to SW5 based on the SOC which is the charge rate of each of the storage batteries 20 and 30 and the drive request for the in-vehicle power supply system 100. Specifically, the battery control unit 31 calculates the SOC of the Li storage battery 30 and controls the charging and discharging of the Li storage battery 30 so that the SOC is maintained within a predetermined range of use.

The battery unit 40 is provided with a first current sensor 32 that detects the current flowing through the switch SW1 and a second current sensor 33 that detects the current flowing through the switch SW2. The current values detected by the first and second current sensors 32 and 33 are input to the battery control unit 31.

The rotary electric machine control unit 13 and the battery control unit 31 are communicably connected via the CAN bus 81. Further, the upper ECU 80 is connected to the CAN bus 81, and the rotary electric machine control unit 13 and the battery control unit 31 can communicate with the upper ECU 80 via the CAN bus 81. When requesting power running to drive the rotary electric machine 11, the upper ECU 80 outputs a power running request signal to the battery control unit 31 and the rotary electric machine control unit 13 via the CAN bus 81. Further, when the host ECU 80 requests regenerative power generation as a drive for the rotary electric machine 11, it outputs a regenerative power generation request signal to the battery control unit 31 and the rotary electric machine control unit 13 via the CAN bus 81.

In the vehicle-mounted power supply system 100 having the above configuration, the switches SW1 to SW4 are in the open state and the switches SW5 are in the closed state before the engine is started. Therefore, the lead-acid battery 20 and the terminal P2 are electrically connected to each other via the bypass path L3, and a dark current flows through the rotary electric machine 11 by the electric power from the lead-acid battery 20.

After the engine is started, power running and regenerative power generation of the rotary electric machine 11 are performed in response to a drive request from the upper ECU 80. During power running, electric power is supplied to the rotary electric machine 11 from either the Li storage battery 30 or the lead storage battery 20. When the rotary electric machine 11 is supplied with power by the Li storage battery 30, the switch SW2 is turned on and the switch SW1 is turned off. When the rotary electric machine 11 is supplied with power by the lead storage battery 20, the switch SW1 is turned on and the switch SW2 is turned off. In the present embodiment, the electric load 43 is supplied by the Li storage battery 30 or the lead storage battery 20 by operating the on / off states of the switches SW3 and SW4 during power running.

At the time of regenerative power generation, the generated power from the rotary electric machine 11 is supplied to at least one of the Li storage battery 30 and the lead storage battery 20. When the Li storage battery 30 is charged by the generated power of the rotary electric machine 11, the switch SW2 is turned on and the switch SW1 is turned off. When the lead-acid battery 20 is charged by the generated power of the rotary electric machine 11, the switch SW1 is turned on and the switch SW2 is turned off. Further, when both the lead storage battery 20 and the Li storage battery 30 are charged, the switches SW1 and SW2 are both turned on.

In the vehicle-mounted power supply system 100 having the above configuration, the switches SW1 and SW2 operated in the ON state may have a sticking abnormality while the rotary electric machine 11 is being driven. Here, the sticking abnormality is an abnormality in which the switches SW1 and SW2 remain in the ON state. In this case, in consideration of the inconvenience caused by the disconnection of the electrical connection between the rotary electric machine 11 and the storage batteries 20 and 30, it is conceivable to prohibit the power running and regenerative power generation of the rotary electric machine 11. However, for example, when an abnormality in sticking of the switch SW2 during the ON operation is detected while the rotary electric machine 11 is assisting the output of the engine, the driver feels uncomfortable due to the stop of the assist by the rotary electric machine 11. There is concern that it will occur. On the other hand, when the rotary electric machine 11 is continuously driven when a sticking abnormality occurs in the switches SW1 and SW2 during the ON operation, the states of the switches SW1 and SW2 in which the sticking abnormality occurs are unstable. Therefore, there is a possibility that the electrical connection between the rotary electric machine 11 and the storage batteries 20 and 30 is cut off by temporarily switching from the on state to the off state.

While the rotary electric machine 11 is being driven, when a sticking abnormality occurs in the switch operated in the ON state among the switches SW1 and SW2, the battery control unit 31 and the rotary electric machine control unit 13 are connected to the rotary electric machine 11. Fail-safe control will be implemented in cooperation to ensure stable driving. In the present embodiment, the battery control unit 31 and the rotary electric machine control unit 13 correspond to the fail-safe control unit.

In the present embodiment, the battery control unit 31 determines that a sticking abnormality has occurred in the switch being turned on among the switches SW1 and SW2 as follows. The operation command for the switches SW1 and SW2 is switched from the on command to the off command, and it is determined whether or not a sticking abnormality has occurred in the switches SW1 and SW2 according to the change in the current flowing after the switching. Specifically, when the operation command for the switch SW1 is switched from the on command to the off command, if the detection current detected by the first current sensor 32 subsequently drops below a predetermined value, the switch being turned on is being operated. It is determined that no sticking abnormality has occurred in SW1, and if the detected detection current does not drop below a predetermined value, it is determined that a sticking abnormality has occurred in switch SW1. Similarly, when the operation command for the switch SW2 is switched from the on command to the off command, if the detection current detected by the second current sensor 33 subsequently drops below a predetermined value, the switch SW2 during the on operation is set. If it is determined that no sticking abnormality has occurred and the detected detection current does not drop below a predetermined value, it is determined that the sticking abnormality has occurred in the switch SW2. In the present embodiment, the battery control unit 31 corresponds to the abnormality determination unit.

In the present embodiment, when the battery control unit 31 determines the sticking abnormality, the switches SW1 and SW2 during the ON operation are temporarily turned off, so that the power supplied to the rotary electric machine 11 is cut off during power running. There is concern about this. Therefore, in the determination of sticking abnormality during power running, during the period in which the switches SW1 and SW2 in the on operation are turned off, the power supplied to the rotary electric machine 11 is generated by turning on the switches SW1 and SW2 in the off state. I try not to be blocked. Specifically, when determining the presence or absence of an abnormality in sticking to the switch SW2 during the on operation, the lead-acid battery 20 and the rotary electric machine 11 are electrically operated by turning on the switch SW1 during the period when the switch SW2 is turned off. Connect to. When determining whether or not there is an abnormality in sticking to the switch SW1 during the ON operation, the rotary electric machine 11 and the Li storage battery 30 are electrically connected by the ON operation of the switch SW2 during the period when the switch SW1 is turned off.

When the battery control unit 31 determines that a sticking abnormality has occurred in the switch being turned on among the switches SW1 and SW2, the battery control unit 31 turns on the switch that is being turned off other than this switch. First, a process will be described when a sticking abnormality occurs in the switch SW2 during the ON operation during power running and regenerative power generation of the rotary electric machine 11.

In FIG. 2A, the switch SW2 is turned on when a power running request is made from the upper ECU 80, and the rotary electric machine 11 is supplied with power by the Li storage battery 30. In this state, when it is determined that the switch SW2 has a sticking abnormality, the switch SW2 is temporarily switched from the on state to the off state, so that the power supply of the rotary electric machine 11 by the Li storage battery 30 is cut off. I am concerned.

As shown in FIG. 2B, the battery control unit 31 conducts an electric path including the switch SW1 between the terminals P1 and P2 by turning on the switch SW1 in the off state. As a result, even when the switch SW2 is temporarily switched from the on state to the off state, the lead storage battery 20 can stably supply power to the rotary electric machine 11.

A fail-safe control when it is determined that a sticking abnormality has occurred in the switch SW2 during the on operation during regenerative power generation will be described. Also in this case, the switch SW2 is operated in the ON state, and the generated power of the rotary electric machine 11 is supplied to the Li storage battery 30. In this state, if it is determined that the switch SW2 has a sticking abnormality, it is assumed that the switch SW2 is temporarily switched from the on state to the off state, so that the power generated by the rotary electric machine 11 is not supplied. To.

The battery control unit 31 conducts an electric path including the switch SW1 between the terminals P1 and P2 by turning on the switch SW1 in the off state. As a result, even when the switch SW2 is temporarily switched from the on state to the off state, the generated power of the rotary electric machine 11 is supplied to the lead storage battery 20.

Compared with the lead storage battery 20, the Li storage battery 30 has less power loss during charging and discharging, and can be charged and discharged with high efficiency. However, the Li storage battery 30 is more likely to be deteriorated by overcharging and overdischarging than the lead storage battery 20. Therefore, the rotary electric machine control unit 13 limits the torques T1r and T2r in order to prevent over-discharging or over-charging of the Li storage battery 30 when it is determined that the switch SW2 has a sticking abnormality. , Continue driving the rotary electric machine 11. Specifically, the rotary electric machine control unit 13 limits the upper limit value of the power running torque T1r so that the voltage between the terminals of the Li storage battery 30 does not fall below the lower limit value of the predetermined output voltage range due to over-discharging during power running. To do. Further, the rotary electric machine control unit 13 limits the upper limit value of the regenerative torque T2r so that the voltage between the terminals of the Li storage battery 30 does not exceed the upper limit value of the output voltage range due to overcharging during the regenerative power generation. The output voltage range is the range of the voltage between terminals recommended in the Li storage battery 30 so as not to accelerate deterioration due to over-discharging and over-charging.

In the present embodiment, when it is determined that the switch SW2 during the ON operation has a sticking abnormality, the rotary electric machine control unit 13 changes the torque target values T1 * and T2 * to the lower side by open control. By doing so, the torque of the rotary electric machine 11 is limited. Specifically, during power running, the power running torque target value T1 * is changed to a value lower than the power running torque target value T1 * when it is determined that the switch SW2 does not have a sticking abnormality. Further, during the regenerative power generation, the regenerative torque target value T2 * is changed to a value lower than the regenerative torque target value T2 * when it is determined that the switch SW2 does not have a sticking abnormality.

Next, a process will be described when a sticking abnormality occurs in the switch SW1 during the on operation during power running. In FIG. 3A, the switch SW1 is in the ON state, and the lead storage battery 20 is supplying power to the rotary electric machine 11. In this state, if the switch SW1 has a sticking abnormality, there is a concern that the power supply to the rotary electric machine 11 by the lead-acid battery 20 may be cut off by temporarily switching the switch SW1 from the on state to the off state.

As shown in FIG. 3B, the battery control unit 31 electrically connects the lead-acid battery 20 and the rotary electric machine 11 through the bypass path L3 by turning on the switch SW5 and turning off the switch SW2. To do. As a result, even when the switch SW1 is temporarily switched from the on state to the off state, the electric power of the lead storage battery 20 is supplied to the rotary electric machine 11 through the bypass path L3.

A fail-safe control when a sticking abnormality occurs in the switch SW1 during the on operation during regenerative power generation will be described. In this case, the switch SW1 is in the ON state, and the electric power generated by the rotary electric machine 11 is supplied to the lead-acid battery 20 through the electric path including the switch SW1. In this state, when the battery control unit 31 determines that a sticking abnormality has occurred in the switch SW1 during the ON operation, the switch SW5 is turned ON, the switch SW2 is turned OFF, and the lead-acid battery 20 and the rotary electric machine 11 are operated. Is electrically connected through the bypass path L3. As a result, even when the switch SW1 is temporarily switched from the on state to the off state, the generated power of the rotary electric machine 11 is supplied to the lead storage battery 20 through the bypass path L3.

The rotary electric machine control unit 13 limits the torques T1r and T2r of the rotary electric machine 11 in order to protect the fuse 50 provided in the bypass path L3 when it is determined that the switch SW1 has a sticking abnormality. In this state, the rotary electric machine 11 is continuously driven. Specifically, the rotary electric machine control unit 13 lowers the torques T1r and T2r of the rotary electric machine 11 compared to the case where it is not determined that the switch SW1 has a sticking abnormality, so that the fuse 50 is provided in the bypass path L3. A current lower than the fusing current value to be blown is passed.

In the present embodiment, when the rotary electric machine control unit 13 determines that the switch SW1 during the ON operation has a sticking abnormality, the torque target values T1 * and T2 * are changed to the lower side by open control. This limits the torques T1r and T2r of the rotary electric machine 11. Specifically, during power running, the power running torque target value T1 * is changed to a value lower than the power running torque target value T1 * when it is not determined that the switch SW1 has a sticking abnormality. Further, at the time of regenerative power generation, the regenerative torque target value T2 * is changed to a value lower than the power running torque target value T1 * when it is not determined that the switch SW2 has a sticking abnormality.

Next, the fail-safe control procedure performed by the battery control unit 31 will be described with reference to FIG. This process is repeatedly performed by the battery control unit 31 at a predetermined cycle.

In step S11, it is determined whether or not there is an abnormality in the sticking of the switch during the on operation. In step S12, it is determined whether or not power running or regenerative power generation is in progress. For example, it is determined that the rotary electric machine 11 is in power running or regenerative power generation depending on the type of drive request from the upper ECU 80.

If the rotary electric machine 11 is in power running or regenerative power generation, the process proceeds to step S13. In step S13, it is determined in step S11 whether or not a sticking abnormality of the switch SW2 during the ON operation is detected. If a sticking abnormality of the switch SW2 during the ON operation is detected, the process proceeds to step S14, and the OFF switch SW1 is turned ON.

In step S15, if the rotary electric machine 11 is currently power running, the process proceeds to step S16. In step S16, an abnormal signal indicating an abnormal state of the switch SW2 is transmitted to the rotary electric machine control unit 13 through the CAN bus 81. When proceeding to step S16, the abnormality signal indicates that a sticking abnormality has occurred in SW2 during power running and on operation.

In step S15, if the rotary electric machine 11 is currently performing regenerative power generation, the process proceeds to step S17. The abnormal signal transmitted in step S17 indicates that a sticking abnormality has occurred in SW2 during the regenerative power generation and the ON operation.

Returning to step S13, if it is determined that the sticking abnormality of the switch SW2 during the ON operation has not been detected, the process proceeds to step S18. In step S18, it is determined in step S11 whether or not a sticking abnormality of the switch SW1 during the ON operation is detected. If it is determined that a sticking abnormality of the switch SW1 during the ON operation is detected, the process proceeds to step S19.

In step S19, the switch SW5 is turned on and the switch SW2 is turned off. In step S20, if the rotary electric machine 11 is currently power running, the process proceeds to step S21, and an abnormal signal indicating an abnormal state of the switch SW1 is transmitted to the rotary electric machine control unit 13 through the CAN bus 81. The abnormality signal transmitted in step S21 indicates that a sticking abnormality has occurred in the switch SW1 during power running and on operation.

In step S20, if the rotary electric machine 11 is currently performing regenerative power generation, the process proceeds to step S22. The abnormal signal transmitted in step S22 indicates that a sticking abnormality has occurred in the switch SW1 during the regenerative power generation and the on operation.

When the process returns to step S18 and it is determined that the switch SW1 has no sticking abnormality, the process of FIG. 4 is temporarily terminated.

Returning to step S12, if it is determined that the rotary electric machine 11 is not in either the driving state during power running or regenerative power generation, the process proceeds to step S23. In step S23, in step S11, it is determined whether or not a sticking abnormality of any of the switches SW1 and SW2 during the off operation is detected. If it is determined in step S23 that a sticking abnormality of the switches SW1 and SW2 during the off operation is detected, the process proceeds to step S24. In step S24, it is transmitted to the rotary electric machine control unit 13 through the CAN bus 81 that a sticking abnormality has occurred in any of the switches SW1 and SW2 during the off operation.

Next, the fail-safe control procedure performed by the rotary electric machine control unit 13 will be described with reference to FIG. This process is repeatedly performed by the rotary electric machine control unit 13 at a predetermined cycle.

In step S30, the abnormal signal transmitted from the battery control unit 31 through the CAN bus 81 is analyzed. In step S31, if it is determined from the analysis result of the abnormality signal in step S30 that a sticking abnormality has occurred in the switch SW2 during power running and on operation, the process proceeds to step S32. In step S32, the power running torque target value T1 * is changed to the lowering side. As a result, the power running torque T1r is limited so that the voltage between the terminals of the Li storage battery 30 does not fall below the lower limit of the output voltage range.

If the negative determination in step S31 is made, the process proceeds to step S33. In step S33, it is determined from the analysis result of the abnormality signal in step S30 whether or not a sticking abnormality has occurred in the switch SW1 during power running and on operation. If the affirmative determination is made in step S33, the process proceeds to step S34, and the power running torque target value T1 * is changed to the lowering side. As a result, the power running torque T1r is limited so that the current flowing in the bypass path L3 does not exceed the fusing current.

If the negative determination in step S33 is made, the process proceeds to step S35. In step S35, it is determined from the analysis result of the abnormality signal in step S30 whether or not a sticking abnormality has occurred in the switch SW2 during the regenerative power generation and the on operation. If the affirmative determination is made in step S35, the process proceeds to step S36, and the regenerative torque target value T2 * is changed to the lower side. As a result, the regenerative torque T2r is limited so that the voltage between the terminals of the Li storage battery 30 does not exceed the upper limit of the output voltage range.

If the negative determination in step S35 is made, the process proceeds to step S37. In step S37, it is determined from the analysis result of the abnormality signal in step S30 whether or not a sticking abnormality has occurred in the switch SW1 during the regenerative power generation and the on operation. If the affirmative determination is made in step S37, the process proceeds to step S38, and the regenerative torque target value T2 * is changed to the lower side. As a result, the regenerative torque T2r is limited so that the current flowing in the bypass path L3 does not exceed the fusing current.

In step S40, it is determined whether or not the request period for power running or regenerative power generation by the upper ECU 80 has expired. If it is determined that the request period has not ended, the process of FIG. 5 is temporarily terminated. In the present embodiment, the required period for power running or regenerative power generation corresponds to the required driving period. When affirmative determination is made in step S40, in step S41, a prohibition request for prohibiting power running and regenerative power generation of the rotary electric machine 11 is transmitted to the upper ECU 80 through the CAN bus 81. As a result, the upper ECU 80 prohibits power running and regenerative power generation of the rotary electric machine 11 by changing the prohibition flag to the high state.

On the other hand, if the negative determination in step S37 is made, the process proceeds to step S39. In step S39, it is determined whether or not a sticking abnormality has occurred in the switches SW1 and SW2 during the off operation based on the analysis result of the abnormality signal in step S30. If the affirmative determination is made in step S39, the process proceeds to step S41, and a prohibition command is transmitted to the upper ECU 80 through the CAN bus 81.

Next, the operations of the battery control unit 31 and the rotary electric machine control unit 13 during fail control will be described using a timing chart. FIG. 6 is a timing chart when it is determined that a sticking abnormality has occurred in the switch SW2 during the on operation during power running. FIG. 6A shows the transition of the presence / absence of the power running request from the upper ECU 80, and FIG. 6B shows the transition of the power running torque T1r. FIG. 6C shows an on / off state of the switch SW1, and FIG. 6D shows an on / off state of the switch SW2. FIG. 6E shows the on / off state of the switch SW5, and FIG. 6F shows the change of the prohibition flag indicating whether or not the power running of the rotary electric machine 11 and the regenerative power generation are prohibited.

Before the time t1, the power running request by the upper ECU 80 is not made, and the power running torque T1r of the rotary electric machine 11 is a value near 0. In the example shown in FIG. 6, it is assumed that the switch SW2 is in the ON state before the time t1. At time t1, the power running of the rotary electric machine unit 10 is performed by the power running request from the upper ECU 80. In FIG. 6B, the period from the time t1 to the time t4 is the drive request period in which the power running request is made to the rotary electric machine 11.

The power running torque T1r of the rotary electric machine 11 is controlled by the rotary electric machine control unit 13 so as to approach the power running torque target value T1 *, so that the power running torque T1r becomes the power running torque target value T1 in the period from time t1 to time t2. Ascends closer to *. After the time t2, the power running torque T1r is maintained at the power running torque target value T1 * by the rotary electric machine control unit 13.

At time t3, when the battery control unit 31 determines that a sticking abnormality has occurred in the switch SW2 during the on operation, the battery control unit 31 turns on the switch SW1 in the off state. The rotary electric machine control unit 13 changes the power running torque target value T1 * to a value lower than the current value by an abnormal signal from the battery control unit 31. As a result, the power running torque T1r of the rotary electric machine 11 is lower than the power running torque T1r before it is determined that the switch SW2 during the ON operation has a sticking abnormality.

At time t4, when the power running request from the upper ECU 80 ends, the rotary electric machine control unit 13 lowers the power running torque target value T1 *. Therefore, the power running torque T1r of the rotary electric machine 11 drops to around 0. Further, the rotary electric machine control unit 13 transmits a prohibition request to the upper ECU 80, so that the prohibition flag for prohibiting the power running and the regenerative power generation of the rotary electric machine 11 becomes a high state, and the power running request and the regenerative power generation request by the upper ECU 80 are prohibited. To.

FIG. 7 is a timing chart when it is determined that a sticking abnormality has occurred in the switch SW1 during the on operation during power running. 7 (a) to 7 (f) correspond to FIGS. 6 (a) to 6 (f), respectively.

Since each operation from time t11 to time t12 is the same as the operation from time t1 to time t2 shown in FIG. 6, description thereof will be omitted. In FIG. 7B, the period from the time t11 to the time t14 is the drive request period in which the power running of the rotary electric machine 11 is required.

At time t13, when the battery control unit 31 determines that a sticking abnormality has occurred in the switch SW1 during the on operation, the battery control unit 31 turns on the switch SW5 during the off operation. The switch SW2 is turned off. Further, the rotary electric machine control unit 13 changes the power running torque target value T1 * to a lower side than the current value by an abnormal signal from the battery control unit 31. As a result, the power running torque T1r of the rotary electric machine 11 is reduced, so that the current flowing through the bypass path L3 is limited to a value lower than the blow current of the fuse 50.

At time t14, the power running request is stopped by the upper ECU 80, so that the rotary electric machine control unit 13 lowers the power running torque target value T1 *. Therefore, the power running torque T1r of the rotary electric machine 11 drops to around 0. Further, when the rotary electric machine control unit 13 transmits a prohibition request to the upper ECU 80, the prohibition flag is set to a high state, and the power running request and the regenerative power generation request by the upper ECU 80 are prohibited.

In the present embodiment described above, the following effects can be obtained.

-The battery control unit 31 determines whether or not a sticking abnormality has occurred in the switch SW1 or the switch SW2 that is being turned on during power running or regenerative power generation of the rotary electric machine 11. When it is determined that a sticking abnormality has occurred in the switch being turned on, the switch in the off state among the switches SW1 and SW2 is operated in the on state. Then, the rotary electric machine control unit 13 continues driving the rotary electric machine 11 in a state where the torque is limited. As a result, even if a sticking abnormality occurs in the switch during the on operation, the rotary electric machine 11 and the storage batteries 20 and 30 can be electrically connected by a switch other than this switch, so that the driver feels uncomfortable. Appropriate measures can be taken for the rotary electric machine 11 without causing the above.

-The rotary electric machine control unit 13 prohibits the drive of the rotary electric machine 11 after continuing while limiting the drive of the rotary electric machine 11 due to a sticking abnormality of the switch during the ON operation. As a result, it is possible to prevent the rotary electric machine 11 from being driven again in a state where a sticking abnormality has occurred in the switch during the ON operation.

-When the rotary electric machine control unit 13 continues to drive the rotary electric machine 11 in a state where the switch SW2 during the ON operation has a sticking abnormality, the voltage between the terminals of the Li storage battery 30 does not deviate from a predetermined output voltage range. The torques T1r and T2r of the rotary electric machine 11 are limited. As a result, it is possible to continue driving the rotary electric machine 11 while suppressing deterioration of the Li storage battery 30.

When the battery control unit 31 determines that a sticking abnormality has occurred in the switch SW1 during the on operation, the battery control unit 31 turns on the switch SW5 to connect the lead storage battery 20 with the lead storage battery 20 via the bypass path L3 without going through the switch SW1. The electrical connection with the rotary electric machine 11 is continued. Further, the rotary electric machine control unit 13 limits the torques T1r and T2r of the rotary electric machine 11 so that the current flowing through the bypass path L3 becomes smaller than the blown current that blows the fuse 50. As a result, when a sticking abnormality occurs in the switch SW1 during the ON operation, the drive of the rotary electric machine 11 can be stably continued while continuing the electrical connection between the lead storage battery 20 and the rotary electric machine 11. Can be done.

(Other embodiments)
-The battery control unit 31 may operate the switch SW2 on when it is determined that the switch SW1 during the on operation has a sticking abnormality. In this case, in step S19 of FIG. 4, the switch SW2 may be turned on. As a result, the rotary electric machine 11 and the Li storage battery 30 are electrically connected via the switch SW2, so that even if the switch SW1 temporarily changes from the on state to the off state during power running, the Li storage battery 30 Power is supplied to the rotary electric machine 11. Further, during regenerative power generation, even if the switch SW1 is temporarily changed from the on state to the off state, the generated power of the rotary electric machine 11 is supplied to the Li storage battery 30.

The blown portion provided in the bypass path L3 may be a blown portion other than a fuse as long as it is blown by a current larger than a predetermined blowing current. For example, in the bypass path L3, a portion where a part of the path width is narrower than the other path width and which is melted due to heat generation due to an overcurrent may be used as the fusing portion.

The vehicle-mounted power supply system 100 may have a configuration in which a resistance portion is provided on the bypass path L3 instead of a configuration in which the switch SW5 is provided on the bypass path L3. In this case, the battery control unit 31 may turn on the switch SW2 when it determines that a sticking abnormality has occurred in the switch SW1 during the on operation.

After receiving the abnormal signal from the battery control unit 31, the rotary electric machine control unit 13 may instruct the battery control unit 31 to turn on / off the switches SW1 to SW3 according to the analysis result of the received abnormal signal. Good.

-Instead of configuring the control device by the battery control unit 31 and the rotary electric machine control unit 13, one control device may be provided with the functions of both the battery control unit 31 and the rotary electric machine control unit 13. ..

11 ... rotary electric machine, 20 ... lead storage battery, 30 ... Li storage battery, 31 ... battery control unit, 13 ... rotary electric machine control unit, 100 ... in-vehicle power supply system.

Claims (4)

Rotating electric machine (11) and
The first storage battery (20) and the second storage battery (30) connected in parallel to the rotary electric machine,
A first switch (SW1) that switches the electrical connection between the rotary electric machine and the first storage battery, and
A second switch (SW2) that switches the electrical connection between the rotary electric machine and the second storage battery, and
Applicable to the in-vehicle power supply system (100)
A control device (13, 31) that operates at least one of the first switch and the second switch in an ON state when driving either power running or power generation of the rotary electric machine.
When either the first switch or the second switch is operated in the on state and the rotary electric machine is driven, whether or not a sticking abnormality has occurred in the switch in the on state among the switches. Abnormality judgment unit to judge and
When it is determined that the sticking abnormality has occurred, the switch in the off state of the first switch and the second switch is operated to the on state within the drive request period of the rotary electric machine at that time. A fail-safe control unit that continues while limiting the drive of the rotary electric machine,
A control device for an in-vehicle power supply system. After the fail-safe control unit finishes driving the rotary electric machine within the drive request period determined by the abnormality determination unit to cause the sticking abnormality, the fail-safe control unit prohibits the subsequent drive of the rotary electric machine. The control device for an in-vehicle power supply system according to claim 1. The second storage battery is a lithium ion storage battery, and the first storage battery is a lead storage battery.
When the fail-safe control unit operates the first switch in the ON state by determining that a sticking abnormality has occurred in the second switch, the voltage between the terminals of the second storage battery is within a predetermined output voltage range. The control device for an in-vehicle power supply system according to claim 1 or 2, wherein the rotary electric machine is continuously driven while being restricted so as to fit. The in-vehicle power supply system includes a third switch (SW5) provided in a bypass path (L3) that connects the rotary electric machine and the first storage battery without going through the first switch.
The bypass path is provided with a fusing portion (50) that is fusing when a current larger than a predetermined fusing current flows.
When it is determined that the second switch has a sticking abnormality, the fail-safe control unit operates the first switch in the ON state, while determining that the first switch has a sticking abnormality. If this is the case, claims 1 to 3 continue driving the rotary electric machine while operating the third switch in the ON state and limiting the current flowing in the bypass path to be smaller than the fusing current. The control device for the in-vehicle power supply system according to any one of the above.

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