JP2017081348A - Power supply control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply control device which can avoid the lowering of the reliability of an electric appliance which is connected to a power supply corresponding to an objective block part even if the objective block part being a relay corresponding to the power supply which is determined in the occurrence of an abnormality out of a high-pressure side relay 68 and a low-pressure side relay 51 is switched to a block state from a conduction state.SOLUTION: A control device 80 performs power control for controlling power which is supplied to the other power supply from either of a high-voltage power supply 10 and an intermediate-voltage power supply 20 to target power. The control device 80 has a function for determining whether or not an abnormality occurs in either of the high-voltage power supply 10 and the intermediate-voltage power supply 20, and switches an objective block part to a block state from a conduction state when it is determined that the abnormality occurs. When it is determined that the abnormality occurs, the control device 80 performs voltage control for controlling a voltage applied to the power supply which is determined in the occurrence of the abnormality from the power supply which is not determined in the occurrence of the abnormality out of the high-voltage power supply 10 and the intermediate-voltage power supply 20 in place of the power control.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power source applied to a vehicle including a rotating electrical machine serving as a vehicle-mounted main machine and a first power source that transmits and receives power via an inverter, and a second power source that supplies power to electrical devices other than the rotating electrical machine. The present invention relates to a control device.

  Conventionally, as can be seen in the following Patent Document 1, it is possible to transmit power between a first power source, a second power source having a larger capacity and a smaller output than the first power source, and the first power source and the second power source. 2. Description of the Related Art There is known a power supply control device that is applied to a vehicle that includes a power converter that performs the operation. In Patent Document 1 below, a capacitor is used as the first power source, and a battery is used as the second power source.

Japanese Patent No. 5580914

  As a power supply control device, between the first power source and the power converter, the first cutoff unit capable of switching between the conduction state and the cutoff state, and between the second power source and the power converter, the conduction state and the cutoff state. Some are applied to a vehicle provided with the 2nd interruption | blocking part which can be switched to either. This control device has a function of determining whether an abnormality has occurred in either the first power supply or the second power supply. The power supply control device switches the target blocking unit, which is a blocking unit corresponding to the power source determined to be abnormal, from the first blocking unit and the second blocking unit from the conductive state to the blocked state. As a result, vehicle safety is ensured.

  Here, when the target cutoff unit is switched to the cutoff state, the power from the power converter cannot be stored in the power source corresponding to the target cutoff unit among the first power source and the second power source. For this reason, there exists a possibility that the fluctuation | variation of the input voltage of the vehicle-mounted electrical equipment connected to the power supply corresponding to an object interruption | blocking part may become large. In this case, there is a concern that the reliability of the electric device may be lowered due to the input voltage of the electric device becoming excessively high or excessively low.

  The present invention is a case where the target blocking unit that is the blocking unit corresponding to the power source determined to have an abnormality among the first blocking unit and the second blocking unit is switched from the conducting state to the blocking state. The main object is to provide a power supply control device capable of avoiding a decrease in reliability of an in-vehicle electrical device connected to a power supply corresponding to a target blocking unit.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  The present invention includes a rotating electrical machine (61) serving as an in-vehicle main machine and a first power source (10) that transfers power via an inverter (63), a second power source (20) that is different from the first power source, Power is supplied from the second power source, and the second power source side device (50), which is an electrical device other than the rotating electrical machine, each of the first power source and the inverter, the second power source and the second power source. A power converter (30) connected to each of the power supply side devices so as to be able to transmit power in both directions, and between the power converter and the inverter and the first power supply in a conduction state and a cutoff state. The first shut-off unit (68) that can be switched to any one of the second power source and the power converter and the second power-side device and the second power source can be switched to either the conductive state or the cut-off state. And 2 blocking portions (51) A normal-time operation unit that is applied to a vehicle and operates the power converter to perform power control for controlling the power supplied from one of the first power supply and the second power supply to the other to the target power (80), an abnormality determination unit (80) for determining whether an abnormality has occurred in any of the first power source and the second power source, and among the first blocking unit and the second blocking unit, The switching unit (80) that switches the target blocking unit that is the blocking unit corresponding to the power source determined to be abnormal by the abnormality determination unit, and the abnormality determination unit determines that an abnormality has occurred. In this case, instead of the power control, the voltage applied to the one of the first power supply and the second power supply that is determined not to be abnormal by the abnormality determination unit but is determined to be abnormal To target voltage That comprises abnormal operation unit for operating the power converter to perform the voltage control and (80), the.

  The above-described invention includes a normal operation unit. The power converter is operated by the normal operation unit to perform power control for controlling the power supplied from one of the first power supply and the second power supply to the other to the target power. Here, the invention further includes an abnormality determination unit and an abnormality operation unit. When it is determined that an abnormality has occurred by the abnormality determination unit, it is determined that an abnormality has occurred from one of the first power source and the second power source that has not been determined to have an abnormality by the abnormality determination unit, instead of power control. In order to perform voltage control for controlling the voltage applied to the target voltage to the target voltage, the power converter is operated by the operation unit during an abnormality.

  As described above, in the above invention, when the abnormality determination unit determines that an abnormality has occurred, the control amount is changed from electric power to voltage. Thereby, the fluctuation | variation of the input voltage of the vehicle-mounted electrical equipment connected to the power supply side determined that abnormality occurred among power converters can be suppressed, and the fall of the reliability of a vehicle-mounted electrical equipment can be avoided. Specifically, for example, when it is determined that an abnormality has occurred in the first power supply, fluctuations in the input voltage of the inverter can be suppressed by operating the power converter by the operation unit at the time of abnormality, and the reliability of the inverter is reduced. Can be avoided. Further, for example, when it is determined that an abnormality has occurred in the second power supply, the power converter is operated by the operation unit at the time of abnormality, so that fluctuations in the input voltage of the second power supply device can be suppressed, and the second power supply device Can be avoided.

The whole block diagram of a vehicle-mounted power supply system. The flowchart which shows the procedure of the fail safe process at the time of high voltage power supply abnormality. The flowchart which shows the procedure of the fail safe process at the time of low voltage power supply abnormality.

  Hereinafter, an embodiment in which a power supply control device according to the present invention is applied to a vehicle will be described with reference to the drawings. The vehicle according to the present embodiment is a hybrid vehicle in which a rotating electric machine and an engine are mounted as a driving power source.

  As shown in FIG. 1, the vehicle has a high-voltage power supply 10 as a first power supply and a medium-voltage power supply 20 as a second power supply. In this embodiment, an output power source is used as the high-voltage power source 10, and a capacitive power source is used as the intermediate-voltage power source 20. The capacity-type power supply has a higher energy density than the output-type power supply, and has a battery capacity, that is, a maximum electric power that can be stored. The output type power supply has a higher output density than the capacitive type power supply and a maximum output larger than that of the capacitive type power supply.

  The output voltage V1 of the high voltage power supply 10 is higher than the output voltage V2 of the medium voltage power supply 20. Specifically, the output voltage of the high-voltage power supply 10 is, for example, a voltage exceeding 100V, and the output voltage of the intermediate-voltage power supply 20 is, for example, a voltage of about 48V. As the high-voltage power supply 10, for example, a lithium ion capacitor (LiC) can be used, and as the intermediate-voltage power supply 20, for example, a lithium ion secondary battery (LiB) can be used.

  The vehicle includes a power converter 30 that connects the high-voltage power supply 10 and the intermediate-voltage power supply 20 in a transformable manner in order to exchange DC power between the high-voltage power supply 10 and the intermediate-voltage power supply 20. In the present embodiment, as the power converter 30, bidirectional insulation that electrically connects the high-voltage power supply 10 and the intermediate-voltage power supply 20 and connects the high-voltage power supply 10 and the intermediate-voltage power supply 20 in a transformable manner. Type DCDC converter is used. Specifically, the power converter 30 is configured to provide power between the intermediate pressure portion 31 and the high pressure portion 32 while electrically insulating the intermediate pressure portion 31, the high pressure portion 32, and the intermediate pressure portion 31 and the high pressure portion 32. A transformer 33 is provided for transmission. The intermediate pressure unit 31 and the high pressure unit 32 include a switching element. Since the bidirectional insulation type DCDC converter is well known, its detailed description is omitted.

  The power converter 30 boosts the output voltage of the intermediate-voltage power supply 20 by operating the switching element and applies it to the high-voltage power supply 10 to perform a boosting operation for supplying power from the intermediate-voltage power supply 20 to the high-voltage power supply 10. . The power converter 30 performs a step-down operation of supplying power from the high-voltage power supply 10 to the intermediate-voltage power supply 20 by stepping down the output voltage of the high-voltage power supply 10 by applying the switching element and applying it to the intermediate-voltage power supply 20. .

  The vehicle includes a chopper type step-down converter 50 that steps down the output voltage of the intermediate-voltage power supply 20 and applies it to the auxiliary load 40 and the low-voltage power supply 41. For example, a voltage of about 14 V is applied to the auxiliary load 40 and the low-voltage power supply 41. In the present embodiment, the auxiliary load 40 includes an electric power steering device, a power window device, a blower, a fan, and the like. The low voltage power supply 41 has an output voltage V3 lower than the output voltage V2 of the medium voltage power supply 20, and for example, a lead storage battery can be used. The low voltage power supply 41 can be a power supply source of the auxiliary load 40.

  The vehicle includes a first motor generator 60, a second motor generator 61, a first inverter 62, and a second inverter 63 as a high-voltage load. In the present embodiment, the first inverter 62 and the second inverter 63 are three-phase inverters. In the present embodiment, the first motor generator 60 and the second motor generator 61 are three-phase ones, for example, synchronous machines.

  The first motor generator 60 is electrically connected to the first inverter 62. The first motor generator 60 serves as a starter or the like that performs initial cranking on the crankshaft of the in-vehicle engine 64 to perform cranking. On the other hand, the 2nd motor generator 61 is electrically connected to the 2nd inverter 63, and plays the role of a vehicle-mounted main machine. The crankshaft of the engine 64 and the second motor generator 61 can transmit power to the drive wheels 66 of the vehicle via the power split mechanism 65. Note that a boost converter may be provided between the first inverter 62 and the second inverter 63 and the high-voltage power supply 10.

  During the power running operation of the first motor generator 60, an AC voltage is applied to the first motor generator 60 from the first inverter 62. During the regenerative operation of the first motor generator 60, the electric power regenerated by the first motor generator 60 is supplied to the high-voltage power supply 10 via the first inverter 62, and further, the intermediate pressure is supplied via the power converter 30. Or supplied to the power source 20.

  The vehicle includes an electric compressor 67 for air conditioning in the vehicle interior as the first power supply side device. The electric compressor 67 pumps the refrigerant in the refrigeration cycle using at least one of the power converter 30 and the high-voltage power supply 10 as a power supply source. Thereby, the cold heat | fever for cooling a vehicle interior is produced | generated. In the present embodiment, the electric compressor 67 includes a motor for pumping the refrigerant and an inverter for driving the motor. Note that the first power supply side device may include other electric devices in addition to the electric compressor 67.

  A smoothing capacitor 62 a is provided on the high voltage part 32 side of the first inverter 62, and a smoothing capacitor is provided on the high voltage part 32 side of the second inverter 63 as well as the first inverter 62. A smoothing capacitor is also provided on the intermediate pressure unit 31 side which is the input side of the step-down converter 50.

  The first inverter 62, the second inverter 63, the inverter of the electric compressor 67, and the power converter 30 exchange power with the high-voltage power supply 10 via the high-voltage side relay 68 serving as a first cutoff unit. Specifically, when the high-voltage side relay 68 is turned on, each of the first inverter 62, the second inverter 63, the inverter of the electric compressor 67, and the high-voltage unit 32 of the power converter 30 is electrically connected to the high-voltage power supply 10. Connected to. On the other hand, when the high voltage side relay 68 is cut off, the first inverter 62, the second inverter 63, the inverter of the electric compressor 67, and the high voltage unit 32 of the power converter 30 are electrically connected to the high voltage power source 10. Blocked.

  The step-down converter 50 and the power converter 30 exchange power with the intermediate-voltage power source 20 via a low-voltage side relay 51 serving as a second cutoff unit. Specifically, when the low-voltage side relay 51 is in a conductive state, each of the step-down converter 50 and the intermediate voltage unit 31 side of the power converter 30 is electrically connected to the intermediate voltage power supply 20. On the other hand, when the low-voltage side relay 51 is in the cut-off state, each of the step-down converter 50 and the intermediate voltage unit 31 side of the power converter 30 is electrically cut off from the medium-voltage power supply 20.

  Note that the power supply system including the high-voltage power supply 10, the intermediate-voltage power supply 20, and the power converter 30 uses the intermediate-voltage power supply 20, which is the power supply with the larger maximum power that can be stored, as the main power supply for the high-voltage load and the auxiliary load 40. Is configured to do. According to this configuration, for the high voltage load and the first power supply side device provided in the high voltage system electrically insulated from the medium voltage system provided with the medium voltage power source 20, the medium voltage power source 20 is necessary. Is supplied with power. In addition, power is also supplied from the intermediate voltage power supply 20 via the step-down converter 50 to the auxiliary load 40 and the low voltage power supply 41 provided in the low voltage system.

  The vehicle includes a brake device 70 that applies a braking force to the wheels by a friction brake. In the present embodiment, a hydraulic device is used as the brake device 70.

  The vehicle includes a high voltage detection unit 71 that can detect the output voltage of the high voltage unit 32, and an intermediate voltage detection unit 72 that can detect the output voltage of the intermediate voltage unit 31. The vehicle has a high-voltage current detector 73 capable of detecting the output current of the high-voltage unit 32 and the current flowing to the high-voltage power supply 10, and the medium-voltage current detection capable of detecting the output current of the intermediate-pressure unit 31 and the current flowing to the intermediate-voltage power supply 20. A portion 74 is provided. The detection value of each detection unit is input to the in-vehicle control device 80.

  The control device 80 controls the power converter 30, the step-down converter 50, the first inverter 62, the second inverter 63, the engine 64, and the like. Specifically, for example, the control device 80 operates the second inverter 63 so as to control the torque of the second motor generator 61 to the target torque.

  Actually, a control device is individually provided for each of the power converter 30, the first inverter 62, the second inverter 63, the engine 64, and the like. In the present embodiment, the point that the control devices are individually provided is not a main part, and for convenience, these control devices are illustrated as a single control device 80.

  The control device 80 includes a regeneration control unit 80a that performs regenerative cooperative brake control. The regenerative control unit 80a includes a required braking torque calculating unit that calculates a required braking torque to be applied to the wheels of the vehicle, a regenerative braking torque generated by regenerative power generation of the second motor generator 61, and a braking torque of the brake device 70. The second inverter 63 and the brake operation unit that operates the brake device 70 are included so that the total value becomes the required braking torque. The required braking torque may be calculated based on the depression amount of a brake pedal (not shown).

  The control device 80 operates each of the low-voltage side relay 51 and the high-voltage side relay 68 to either the conduction state or the cutoff state. The control device 80 performs control to supply power to the high-voltage power supply 10 side using the intermediate-voltage power supply 20 as a power supply source while keeping the low-voltage relay 51 and the high-voltage relay 68 in a conductive state. This control is power control in which the switching element of the power converter 30 is operated to feedback control the output power of the high voltage unit 32 to the target power. The output power of the high voltage unit 32 is calculated based on the first voltage VHr, which is a voltage detected by the high voltage detection unit 71, and the first current IHr, which is a current detected by the high voltage current detection unit 73. Just do it.

  On the other hand, the control device 80 keeps each of the low-voltage side relay 51 and the high-voltage side relay 68 in a conductive state, and uses at least one of the high-voltage power supply 10 and the regenerative generated power of the second motor generator 61 as a power supply source. Control to supply power to the 20 side is performed. This control is power control for operating the switching element of the power converter 30 to feedback control the output power of the intermediate pressure unit 31 to the target power. The output power of the intermediate voltage unit 31 is based on the second voltage VMr that is a voltage detected by the intermediate voltage detector 72 and the second current IMr that is a current detected by the intermediate voltage current detector 74. It may be calculated as follows.

  By the way, when an abnormality occurs in any of the high-voltage power supply 10 and the intermediate-voltage power supply 20, it is necessary to switch the relay corresponding to the power supply in which the abnormality has occurred from the conductive state to the cutoff state from the viewpoint of ensuring vehicle safety. Then, the vehicle is evacuated and traveled using a power supply in which no abnormality has occurred as a power supply source of the second motor generator 61. However, when the relay is switched to the cut-off state, the inconvenience described below may occur.

  If the high-voltage side relay 68 is switched to the cutoff state when an abnormality occurs in the high-voltage power supply 10, the high-voltage power supply 10 does not function as a tray for the output power of the high-voltage unit 32 and the regenerative power generation of the second motor generator 61. In this case, the output power of the high voltage unit 32 and the regenerative power generation power of the second motor generator 61 are only the smoothing capacitors of the first inverter 62 and the second inverter 63, and the regenerative power reception is reduced. As a result, the input voltage of the second inverter 63 tends to fluctuate, and the fluctuation range of the input voltage of the second inverter 63 increases. Thereby, the torque fluctuation of the 2nd motor generator 61 becomes large, and there exists a possibility that drivability may fall. Further, when the high voltage side relay 68 is switched to the cut-off state, the fluctuation range of the input voltage of the first inverter 62, the second inverter 63, and the electric compressor 67 becomes large, and the first inverter 62, the second inverter 63, and the electric compressor 67 The input voltage becomes too high or too low. Thereby, there exists a possibility that the reliability of the 1st inverter 62, the 2nd inverter 63, and the electric compressor 67 may fall.

  On the other hand, if the low-voltage relay 51 is switched to the cut-off state when an abnormality occurs in the intermediate-voltage power supply 20, the intermediate-voltage power supply 20 does not function as a tray for the output power of the intermediate-pressure unit 31. In this case, the output power receiving tray of the intermediate pressure unit 31 is only the smoothing capacitor of the step-down converter 50 or the like. As a result, the fluctuation range of the input voltage of the step-down converter 50 is increased, and there is a concern that the reliability of the step-down converter 50 is lowered. Actually, when the fluctuation range of the input voltage of step-down converter 50 increases, the step-down converter 50 is abnormally stopped by the protection function of step-down converter 50.

  In order to solve the above-described problem, in this embodiment, when an abnormality occurs in either the high-voltage power supply 10 or the intermediate-voltage power supply 20, the control device 80 performs the fail-safe process shown in FIGS.

  First, the fail-safe process when an abnormality occurs in the high-voltage power supply 10 will be described with reference to FIG.

  In this series of processing, first, in step S10, it is determined whether or not an abnormality has occurred in the high-voltage power supply 10. In the present embodiment, whether or not an abnormality has occurred in the high-voltage power supply 10 is determined based on the first voltage VHr that is a voltage detected by the high-voltage voltage detector 71. Specifically, for example, it may be determined that an abnormality has occurred in the high-voltage power supply 10 when the first voltage VHr deviates from the control range. In the present embodiment, the process of step S10 corresponds to an abnormality determination unit.

  When an affirmative determination is made in step S10, the process proceeds to step S11, in which the target power output from the high voltage unit 32 side of the power converter 30 in the power control of the power converter 30 is made equal to the input power of the second inverter 63; Processing for stopping the operation of the electric compressor 67 and processing for prohibiting regenerative cooperative brake control are performed. In the present embodiment, the process of step S11 includes a first power supply side operation unit and a stop unit.

  First, a process for making the target power equal to the input power of the second inverter 63 will be described. This process is a process for switching the high voltage side relay 68 to the cut-off state in a state where the current flowing through the high voltage side relay 68 is close to 0 and avoiding the welding of the high voltage side relay 68.

  That is, in order to bring the current flowing through the high-voltage side relay 68 close to 0, the operation of the second inverter 63 may be stopped. However, in this case, the power running operation by the second motor generator 61 cannot be performed, and the drivability may be reduced. Therefore, in order to make the current flowing through the high voltage side relay 68 close to 0 without stopping the operation of the second inverter 63, the target power output from the power converter 30 is made equal to the input power of the second inverter 63. . In particular, in the present embodiment, by performing the process of stopping the operation of the electric compressor 67, the current flowing through the high-voltage side relay 68 is reliably brought close to zero. This avoids occurrence of welding of the high voltage side relay 68 when the high voltage side relay 68 is switched to the cut-off state. Since electric power is input to the second inverter 63, traveling of the vehicle is assisted by the driving torque of the second motor generator 61.

  Incidentally, the power supply source of the second inverter 63 when the high-voltage side relay 68 is switched to the cut-off state is the medium-voltage power supply 20. For this reason, it is desirable to perform a process of guarding the input power of the second inverter 63 so that the input power of the second inverter 63 is less than or equal to the allowable output power of the intermediate voltage power supply 20.

  Next, processing for prohibiting regenerative cooperative brake control will be described. This process is a process for avoiding a decrease in drivability. That is, when an abnormality occurs in the high-voltage power supply 10 and the high-voltage side relay 68 is switched to the cut-off state, the regenerative power generated by the second motor generator 61 cannot be stored in the high-voltage power supply 10 via the second inverter 63. The maximum value of regenerative power that can be accepted by the power supply system is reduced. In this case, it is necessary to supplement the regenerative braking torque corresponding to the reduced regenerative generated power with the braking torque of the brake device 70. However, due to the low responsiveness of the brake device 70, there is a concern that the actual braking torque is temporarily insufficient with respect to the required braking torque, and drivability is reduced.

  Accordingly, when it is determined that an abnormality has occurred in the high-voltage power supply 10, the regenerative power generation of the second motor generator 61 is prohibited, and the brake device 70 is operated so that the braking torque of the brake device 70 becomes the required braking torque. As a result, a temporary shortage of the actual braking torque with respect to the required braking torque is suppressed, and a decrease in drivability is avoided.

  In the subsequent step S12, a first condition that the first current IHr has become equal to or lower than the high-voltage side threshold value IHth, and a second condition that the elapsed time THr from the start of the process in step S12 has elapsed the high-voltage side threshold time THth. It is determined whether the logical sum of is true. The first condition is a condition for determining whether or not the current flowing through the high-voltage side relay 68 has approached zero. The second condition is a condition for avoiding a state where the actual output power is insufficient with respect to the output power of the driving power source requested by the driver. That is, if the time until the first current IHr becomes equal to or lower than the high-voltage side threshold value IHth after the process of step S12 is started, the state where the actual output power is insufficient becomes longer, and drivability may be reduced. For this reason, by providing the second condition, it is suppressed that the time until the start process of the engine 64 is subsequently executed in step S18 is prevented, and a decrease in drivability is avoided.

  When an affirmative determination is made in step S12, the process proceeds to step S13, and the high voltage side relay 68 is switched from the conductive state to the cut-off state. In the present embodiment, the process of step S13 corresponds to a switching unit.

  In the following step S14, the third condition that the first voltage VHr is out of the predetermined range and the logic of the fourth condition that the elapsed time TH1 since the processing in step S14 is equal to or greater than the first predetermined time Tα1. Determine whether the sum is true. Here, the third condition is a condition for capturing whether the output voltage of the high-voltage unit 32 has become unstable and determining whether it is a timing to switch from power control to voltage control. The fourth condition is a condition provided for the same purpose as the second condition.

  In subsequent step S15, the power control is switched to the voltage control. This process is a process for suppressing fluctuations in the input voltage of the second inverter 63 and the like by changing the control amount of the power converter 30 from the output power to the output voltage. The voltage control is a control for operating the switching element of the power converter 30 so as to feedback-control the first voltage VHr to the target voltage VHtgt. In the present embodiment, both the step-up operation and the step-down operation of the power converter 30 are not limited even when switched to voltage control. Incidentally, in the present embodiment, the process of step S15 corresponds to an operation unit at the time of abnormality.

  In the subsequent step S16, a fifth condition that the first voltage VHr has converged to the target voltage VHtgt, and a sixth condition that the elapsed time TH2 since the start of the process in step S16 has become equal to or greater than the second predetermined time Tα2. It is determined whether the logical sum of is true. The sixth condition is a condition provided for the same purpose as the second condition.

  In a succeeding step S17, it is determined whether or not the engine 64 is stopped. If an affirmative determination is made in step S17, an initial explosion is generated in the engine 64 by performing the cranking process by the first motor generator 60 and the combustion control process of the engine 64 in steps S18 and S19. Start. In the present embodiment, the processes in steps S17 to S19 correspond to the engine starting unit.

  If an affirmative determination is made in step S19 or a negative determination is made in step S17, the process proceeds to step S20. In step S20, the operation of the first power supply side device including the electric compressor 67 is restored. By restarting the operation of the electric compressor 67, it is possible to restart the generation of cold heat necessary for cooling the passenger compartment. In the present embodiment, the process of step S20 corresponds to a return unit.

  Next, a fail-safe process when an abnormality occurs in the medium-voltage power supply 20 will be described using FIG.

  In this series of processing, first, in step S30, it is determined whether or not an abnormality has occurred in the intermediate voltage power source 20. In the present embodiment, it is determined based on the second voltage VMr whether or not an abnormality has occurred in the intermediate voltage power supply 20. Specifically, for example, when the second voltage VMr deviates from the control range, it may be determined that an abnormality has occurred in the intermediate voltage power supply 20. In the present embodiment, the process of step S30 corresponds to an abnormality determination unit.

  When an affirmative determination is made in step S30, the process proceeds to step S31, and the operations of the power converter 30 and the step-down converter 50 are stopped. This process is a process for avoiding occurrence of welding of the low-pressure side relay 51 by switching the low-voltage side relay 51 to the cut-off state in a state where the current flowing through the low-voltage side relay 51 is zero or close to zero. In this embodiment, the process of step S31 includes a second power supply side operation unit and a stop unit.

  In a succeeding step S32, it is determined whether or not the engine 64 is stopped. If an affirmative determination is made in step S32, an initial explosion is generated in the engine 64 by performing the cranking process by the first motor generator 60 and the combustion control process of the engine 64 in steps S33 and S34. Start.

  If an affirmative determination is made in step S34 or a negative determination is made in step S32, the process proceeds to step S35. In step S35, the seventh condition that the second current IMr has become equal to or lower than the low-pressure side threshold value IMth and the eighth condition that the elapsed time TMr from the start of the process in step S35 has passed the low-voltage side threshold time TMth. It is determined whether the logical sum is true. The seventh condition is a condition for determining whether or not the current flowing through the low-voltage relay 51 has become zero or has approached zero.

  When an affirmative determination is made in step S35, the process proceeds to step S36, and the low-voltage side relay 51 is switched from the conductive state to the cut-off state. In the present embodiment, the process of step S36 corresponds to a switching unit.

  In the subsequent step S37, it is determined whether or not the condition that the elapsed time TM1 from the start of the process in step S37 is equal to or longer than the third predetermined time Tα3 is satisfied.

  If an affirmative determination is made in step S37, the process proceeds to step S38, and the power control is switched to the voltage control. The voltage control is a control for operating the switching element of the power converter 30 so as to feedback-control the second voltage VMr to the target voltage VMtgt. In the present embodiment, in the voltage control, only the step-down operation of the power converter 30 is allowed and the step-up operation is prohibited. Incidentally, in the present embodiment, the process of step S38 corresponds to the operation unit at the time of abnormality.

  In the subsequent step S39, the logical sum of the condition that the second voltage VMr has converged to the target voltage VMtgt and the condition that the elapsed time TM2 since the processing in step S39 started is equal to or greater than the fourth predetermined time Tα4. Determine if true.

  When an affirmative determination is made in step S39, the process proceeds to step S40, and the operation of the step-down converter 50 is restored. In the present embodiment, the process of step S40 corresponds to a return unit.

  According to the embodiment described in detail above, the following effects can be obtained.

  When it is determined that an abnormality has occurred in the high-voltage power supply 10, the first voltage VHr is switched to the voltage control that controls the target voltage VHtgt instead of the power control that controls the output power from the high-voltage unit 32 side to the target power. For this reason, the torque fluctuation of the 2nd motor generator 61 can be suppressed, and the fall of drivability can be avoided, or the fall of reliability of the 2nd inverter 63 grade | etc., Can be avoided.

  Further, when it is determined that an abnormality has occurred in the intermediate voltage power supply 20, instead of the power control for controlling the output power from the intermediate voltage unit 31 side to the target power, the voltage control for controlling the second voltage VMr to the target voltage VMtgt is performed. Switched. For this reason, fluctuations in the input voltage of the step-down converter 50 can be suppressed, and a decrease in the reliability of the step-down converter 50 can be avoided.

  When it was determined that an abnormality occurred in the high-voltage power supply 10, the power converter 30 and the second inverter 63 were operated so that the input / output power of the high-voltage power supply 10 was close to zero. Then, the high-voltage side relay 68 was switched to the cut-off state while the input / output power of the high-voltage power supply 10 was brought close to zero. Thereby, generation | occurrence | production of the welding of the high voltage | pressure side relay 68 can be avoided.

  When it was determined that an abnormality occurred in the high-voltage power supply 10, the operation of the first power supply side device including the electric compressor 67 was stopped. The input / output power of the high-voltage power supply 10 can be made closer to 0 by stopping the operation of the electric equipment not involved in the traveling of the vehicle.

  When it is determined that an abnormality has occurred in the high-voltage power supply 10, the regenerative cooperative brake control is prohibited, and the brake device 70 is operated so that the braking torque of the brake device 70 becomes the required braking torque. Thereby, it is possible to suppress a temporary shortage of the actual braking torque with respect to the required braking torque, and it is possible to avoid a decrease in drivability.

  When it is determined that an abnormality has occurred in the high-voltage power supply 10, the engine 64 is started when the engine 64 is stopped. When the high-voltage side relay 68 is switched to the cut-off state, the power supply source of the second motor generator 61 is only the medium-voltage power supply 20, so that the power required for the second motor generator 61 is insufficient, and the second motor generator 61. There is a concern that the output power of will be insufficient. In particular, since the high-voltage power supply 10 is a high-output type power supply, it is impossible to meet the acceleration request, and there is a concern that drivability is reduced. In this regard, in this embodiment, the engine 64 can cover the shortage of output power of the second motor generator 61. For this reason, a decrease in drivability can be avoided, and the vehicle can be properly evacuated.

  In particular, in this embodiment, when it is determined that an abnormality has occurred in the high-voltage power supply 10, when the engine 64 is stopped, the engine 64 is started in a state where the operation of the first power supply side device including the electric compressor 67 is stopped. It was. For this reason, the situation where the electric power required for cranking by the first motor generator 60 is insufficient can be avoided, and the engine 64 can be started accurately.

  When it was determined that an abnormality occurred in the high-voltage power supply 10, cranking was performed by the first motor generator 60 with the first voltage VHr converged to the target voltage VHtgt. For this reason, it is possible to prevent the operation of the first motor generator 60 from becoming unstable, and the engine 64 can be started accurately.

  When it was determined that an abnormality occurred in the high-voltage power supply 10, the operation of the first power supply side device including the electric compressor 67 was stopped, and the operation of the first power supply side device was restored after the engine 64 was started. For this reason, it is possible to maintain the comfort in the passenger compartment as much as possible when the vehicle is evacuated.

  When it is determined that an abnormality has occurred in the medium-voltage power supply 20, the low-voltage side relay 51 is switched to the cut-off state while the operations of the power converter 30 and the step-down converter 50 are stopped. Thereby, generation | occurrence | production of the welding of the low voltage | pressure side relay 51 can be avoided.

(Other embodiments)
The above embodiment may be modified as follows.

  In the above embodiment, the electric motor that performs cranking is not limited to the first motor generator 60. For example, a starter that is an auxiliary load 40 that uses the low-voltage power supply 41 as a power supply source may be used in a vehicle that does not include the first motor generator 60 and the first inverter 62 as an electric motor that performs cranking.

  In the above embodiment, the operation of the step-down converter 50 is stopped when the medium-voltage power supply 20 is abnormal, but the present invention is not limited to this. For example, by operating the power converter 30 and the step-down converter 50 so that the output power from the intermediate pressure unit 31 side and the power taken out to the auxiliary load 40 side through the step-down converter 50 are equal, The current flowing through the side relay 51 may be close to zero.

  The second power supply side device may include an electrical device other than the step-down converter 50.

  In the above embodiment, the high-voltage power supply may be a capacitive power supply, and the medium-voltage power supply may be an output power supply.

  -As a interruption | blocking part, another interruption | blocking part may be sufficient as long as it has the function similar to a relay, not only a relay.

  In the above-described embodiment, the output voltages of the high-voltage power supply 10 and the medium-voltage power supply 20 that are two power supplies provided in the power supply system are different from each other. In this case, a non-insulated DCDC converter that does not electrically insulate between the two power sources may be used as the power converter.

  The vehicle is not limited to a hybrid vehicle, and may be a vehicle having another power generation source such as a vehicle having a fuel cell. The vehicle may be a vehicle that includes only a motor generator as a driving power source.

  DESCRIPTION OF SYMBOLS 10 ... High voltage power source, 20 ... Medium voltage power source, 30 ... Power converter, 40 ... Auxiliary load, 51 ... Low voltage side relay, 61 ... Second motor generator, 63 ... Second inverter, 68 ... High voltage side relay, 80 ... Control device.

Claims (12)

A first electric power source (10) that transmits and receives electric power via a rotating electric machine (61) that is an in-vehicle main machine and an inverter (63);
A second power source (20) different from the first power source;
A second power supply side device (50) which is supplied with electric power from the second power supply and is an electric device other than the rotating electrical machine;
A power converter (30) for connecting the first power source and the inverter and the second power source and each of the second power source side devices so as to be able to transmit power bidirectionally;
A first shut-off unit (68) capable of switching between each of the power converter and the inverter and the first power supply to either a conductive state or a cut-off state;
Applied to a vehicle comprising: a second shut-off unit (51) capable of switching between the power converter and each of the second power supply side devices and the second power source to either a conductive state or a cut-off state;
A normal operation unit (80) for operating the power converter to perform power control for controlling the power supplied from one of the first power supply and the second power supply to the other to the target power;
An abnormality determination unit (80) for determining whether an abnormality has occurred in any of the first power supply and the second power supply;
Of the first blocking unit and the second blocking unit, a switching unit (80) for switching the target blocking unit corresponding to the power source determined to be abnormal by the abnormality determination unit from the conduction state to the blocking state When,
When it is determined that an abnormality has occurred by the abnormality determination unit, instead of the power control, an abnormality is detected from the first power source and the second power source that is not determined to have an abnormality by the abnormality determination unit. An abnormality control unit (80) for operating the power converter in order to perform voltage control for controlling a voltage applied to a direction determined to have occurred to a target voltage. When it is determined by the abnormality determination unit that an abnormality has occurred in the first power supply, the output power from the power converter to the first power supply side and the input power of the inverter are made equal to each other. A first power supply side operation unit (80) for operating the power converter and the inverter so that the input / output power approaches 0;
The switching unit switches the first blocking unit to a blocking state in a state where the input / output power of the first power supply is brought close to 0 by the first power supply side operation unit,
2. The power supply control device according to claim 1, wherein the abnormal-time operation unit operates the power converter to perform the voltage control in a state where the first interruption unit is switched to an interruption state. The vehicle is provided with a first power supply side device (67) that is an electrical device other than the power converter and the inverter and is electrically connected to the first power supply side of the power converter. ,
The power supply control device according to claim 2, further comprising a stop unit that stops the operation of the first power supply side device when the abnormality determination unit determines that an abnormality has occurred in the first power supply. The vehicle is provided with a friction brake device (70) for applying braking force to wheels,
The inverter and the friction brake device are configured to realize a required braking torque to be applied to the wheel by a regenerative braking torque applied to the wheel by regenerative power generation of the rotating electrical machine and a braking torque of the friction brake device. It has a brake operation part (80) to operate,
When the abnormality determining unit determines that an abnormality has occurred in the first power supply, the brake operation unit prohibits regenerative power generation of the rotating electrical machine, and the braking torque of the friction brake device becomes the required braking torque. The power supply control device according to any one of claims 1 to 3, wherein the friction brake device is operated. The vehicle is provided with an engine (64) serving as an in-vehicle main machine,
The engine start unit (80) for starting the engine when the engine is stopped when the abnormality determination unit determines that an abnormality has occurred in the first power supply. The power supply control device according to item. The vehicle includes an electric motor (62) that is electrically connected to the first power source side of the power converter and cranks the engine.
6. The engine starting unit according to claim 5, wherein the engine is started by performing the cranking by the electric motor in a state where a voltage applied from the power converter to the electric motor has converged to the target voltage. Power control device. The vehicle is provided with a first power supply side device (67) that is an electrical device other than the power converter and the inverter and is electrically connected to the first power supply side of the power converter. ,
When it is determined by the abnormality determination unit that an abnormality has occurred in the first power supply, a stop unit that stops the operation of the first power supply side device;
The power supply control device according to claim 5, further comprising a return unit (80) for returning the operation of the first power supply side device after the engine is started by the engine starter. A second power supply that operates the power converter and the second power supply side device so that the input / output power of the second power supply approaches 0 when the abnormality determination unit determines that an abnormality has occurred in the second power supply. Side operation part (80),
The switching unit switches the second blocking unit to a blocking state in a state where the input / output power of the second power source is brought close to 0 by the second power supply side operation unit,
The power source according to any one of claims 1 to 7, wherein the abnormality operation unit operates the power converter to perform the voltage control in a state where the second blocking unit is switched to a blocking state. Control device. The second power supply side device includes a step-down converter (50) for stepping down and outputting the output voltage of the second power supply,
The second power supply side operation unit sets the input / output power of the second power supply to 0 by stopping the operations of the power converter and the step-down converter,
The power supply control device according to claim 8, wherein the switching unit switches the second blocking unit to a blocking state in a state where input / output power of the second power supply is set to 0 by the second power supply side operation unit. The second power source has a lower output voltage than the first power source,
The power converter connects the first power source and the inverter to the second power source and the second power source side device so as to be capable of bidirectional transformation. The power supply control device according to any one of the above.   The power converter electrically isolates each of the first power source and the inverter from each of the second power source and the second power source side device, and each of the first power source and the inverter. The power supply control device according to claim 10, wherein the second power supply and each of the second power supply side devices are connected in a bidirectionally transformable manner. The first power source is an output type power source;
12. The second power source is a capacitive power source that has a larger amount of power that can be stored than the output power source and has a smaller output than the output power source. Power control device.

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