JP2008035581A - Vehicle power supply - Google Patents

Abstract

A power supply device for a vehicle capable of quickly raising the temperature of a power storage device when the vehicle is started.
A connecting portion is electrically connected between a battery B and a power supply line PL1 and arranged at a position where heat can be transferred to the battery B, and the battery B and the power supply line PL1. System main relay SMR1 electrically connected in series with resistor R1 and system main relay SMR2 directly connecting battery B and power supply line PL1. Control device 30 turns on system main relay SMR2 after turning on system main relay SMR1 in response to vehicle activation instruction IGON.
[Selection] Figure 1

Description

  The present invention relates to a vehicle power supply device, and more particularly to a vehicle power supply device that supplies power to a motor that rotates a wheel.

  In a vehicle equipped with a storage battery that supplies power to a motor that rotates a wheel such as an electric vehicle, it may be necessary to manage the temperature of the storage battery. In an application such as a vehicle that may be left for a long time in various environments, the storage battery may be at a very low temperature when the vehicle is started. This is because the storage battery generally has a lower input / output power at a very low temperature than at a normal temperature.

In Japanese Patent Laid-Open No. 11-283678 (Patent Document 1), resistors are connected in parallel to each of a plurality of cells connected in series so that the cells are uniformly charged. Has disclosed a charge control device capable of quickly raising the temperature of the assembled battery using the thermal energy generated in the above.
JP-A-11-283678 JP 2004-7950 A

  However, the charge control device disclosed in Japanese Patent Application Laid-Open No. 11-283678 (Patent Document 1) causes the current to flow through the resistor when the regenerative power during regenerative charging is large, thereby bypassing the current. The temperature cannot be increased. Therefore, there is a problem that the temperature cannot be increased immediately when the vehicle is started after parking at a low temperature for a long time.

  An object of the present invention is to provide a power supply device for a vehicle that can quickly raise the temperature of a power storage device when the vehicle is started.

  In summary, the present invention relates to a power supply device for a vehicle, which is connected to a power storage device, a power supply line, a load circuit, supplied with a current from the power supply line, and charged, and connected to the power supply line. A connecting portion. The connecting portion is electrically connected between the power storage device and the power supply line and is disposed at a position where heat can be transferred to the power storage device, and electrically connected between the power storage device and the power supply line. A first relay connected in series and a second relay that directly connects the power storage device and the power supply line are included. The power supply device for a vehicle further includes a control device for turning on the second relay after turning on the first relay in response to a vehicle activation instruction.

Preferably, the resistor is arranged at a lower portion of the power storage device.
Preferably, the resistor includes a plurality of resistors distributed in a lower portion of the power storage device.

Preferably, the resistor includes a linear heating element disposed along the power storage device.
Preferably, the resistor includes a planar heating element disposed along the power storage device.

  Preferably, the power supply device for the vehicle further includes a temperature sensor that detects the temperature of the power storage device and notifies the control device. The control device maintains the state where the first relay is turned on and the second relay is turned off until the temperature of the power storage device becomes higher than a predetermined temperature.

  Preferably, the power supply device for the vehicle further includes a temperature sensor that detects the temperature of the power storage device and notifies the control device, a passage that allows cooling air to flow in the order of the power storage device, and a resistance, and a blower provided in the passage. Prepare. When the temperature of the power storage device is lower than the predetermined temperature, the control device controls the blower to cause the wind to flow backward from the resistance toward the power storage device.

  According to another aspect of the present invention, there is provided a power supply device for a vehicle, wherein the power supply device is connected to a plurality of power storage devices, a plurality of power supply lines respectively provided corresponding to the plurality of power storage devices, and a load circuit. A capacitor that is supplied with current from the line and charged; and a plurality of connection portions that connect the plurality of power storage devices to the plurality of power supply lines, respectively. Each of the plurality of connecting portions is electrically connected between the corresponding power storage device and the corresponding power supply line, and is disposed at a position where heat can be transferred to the corresponding power storage device, and the power storage device and the power source A first relay electrically connected in series with the resistor between the line and a second relay directly connecting the power storage device and the power line. The power supply device for a vehicle further includes a control device for turning on the second relay after turning on the first relay in response to a vehicle activation instruction.

  Preferably, the control device discharges the first power storage device of the plurality of power storage devices to charge the second charging device of the plurality of power storage devices, and the second power storage device And a second control cycle in which the first charging device is charged. When the power consumption of the load circuit is less than a predetermined value and the temperature of the power storage device is lower than the predetermined temperature, the control device makes the first relay conductive and the second relay nonconductive. The first control cycle and the second control cycle are repeatedly executed.

  According to the present invention, the temperature of the power storage device can be quickly raised when the vehicle is started.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a diagram showing a main configuration of a vehicle 100 according to Embodiment 1 of the present invention. The vehicle 100 is a hybrid vehicle that uses a motor and an engine for driving the vehicle. However, the present invention can also be applied to an electric vehicle, a fuel cell vehicle, and the like that drive wheels with a motor.

  Referring to FIG. 1, vehicle 100 includes a battery B, a connection unit 40, a boost converter 12, smoothing capacitors C1 and C2, voltage sensors 13 and 21, a load circuit 23, an engine 4, and a motor. Generators MG 1, MG 2, power split device 3, wheels 2, and control device 30 are included.

Vehicle 100 further includes power supply lines PL1 and PL2, ground line SL, voltage sensor 10 for detecting voltage VB between terminals of battery B, current sensor 11 for detecting current IB flowing through battery B, and battery B. And a temperature sensor 42 for detecting the temperature. As the battery B, for example, a secondary battery such as a lead storage battery, a nickel metal hydride battery, or a lithium ion battery can be used. The connection unit 40 is a system main relay connected between the negative electrode of the battery B and the ground line SL. SMR3, system main relay SMR2 connected between the positive electrode of battery B and power supply line PL1, and resistor R1 and system main relay SMR1 connected in series with system main relay SMR2 are included. System main relays SMR1-SMR3 are controlled to be in a conductive / non-conductive state in accordance with control signals CONT1-CONT3 supplied from control device 30, respectively.

  Capacitor C1 smoothes the voltage across terminals of battery B when system main relays SMR1 to SMR3 are on. Capacitor C1 is connected between power supply line PL1 and ground line SL. An electric air conditioner 35, which is a load circuit, is connected between the power supply line PL1 and the ground line SL.

  The voltage sensor 21 detects the voltage VL across the capacitor C1 and outputs it to the control device 30. Boost converter 12 boosts the voltage across terminals of capacitor C1. Capacitor C2 smoothes the voltage boosted by boost converter 12. The voltage sensor 13 detects the inter-terminal voltage VH of the smoothing capacitor C <b> 2 and outputs it to the control device 30.

  Load circuit 23 includes inverters 14 and 22. Inverter 14 converts the DC voltage applied from boost converter 12 into a three-phase AC and outputs the same to motor generator MG1.

  Power split device 3 is a mechanism that is coupled to engine 4 and motor generators MG1 and MG2 and distributes power between them. For example, as the power split mechanism, a planetary gear mechanism having three rotating shafts of a sun gear, a planetary carrier, and a ring gear can be used. These three rotation shafts are connected to the rotation shafts of engine 4 and motor generators MG1, MG2, respectively.

  The rotating shaft of motor generator MG2 is coupled to wheel 2 by a reduction gear and an operating gear (not shown). Further, a reduction gear for the rotation shaft of motor generator MG2 may be further incorporated in power split device 3. Moreover, you may comprise so that the reduction ratio of this reduction gear can be switched.

  Boost converter 12 is connected in parallel to reactor L1 having one end connected to power supply line PL1, IGBT elements Q1 and Q2 connected in series between power supply line PL2 and ground line SL, and IGBT elements Q1 and Q2. And diodes D1 and D2 connected to each other.

  Reactor L1 has the other end connected to the emitter of IGBT element Q1 and the collector of IGBT element Q2. The cathode of diode D1 is connected to the collector of IGBT element Q1, and the anode of diode D1 is connected to the emitter of IGBT element Q1. The cathode of diode D2 is connected to the collector of IGBT element Q2, and the anode of diode D2 is connected to the emitter of IGBT element Q2.

  Inverter 14 receives the boosted voltage from boost converter 12 and drives motor generator MG1 to start engine 4, for example. Inverter 14 returns the electric power generated by motor generator MG 1 by the power transmitted from engine 4 to boost converter 12. At this time, boost converter 12 is controlled by control device 30 to operate as a step-down circuit.

  Inverter 14 includes a U-phase arm 15, a V-phase arm 16, and a W-phase arm 17. U-phase arm 15, V-phase arm 16, and W-phase arm 17 are connected in parallel between power supply line PL2 and ground line SL.

  U-phase arm 15 includes IGBT elements Q3 and Q4 connected in series between power supply line PL2 and ground line SL, and diodes D3 and D4 connected in parallel with IGBT elements Q3 and Q4, respectively. The cathode of diode D3 is connected to the collector of IGBT element Q3, and the anode of diode D3 is connected to the emitter of IGBT element Q3. The cathode of diode D4 is connected to the collector of IGBT element Q4, and the anode of diode D4 is connected to the emitter of IGBT element Q4.

  V-phase arm 16 includes IGBT elements Q5 and Q6 connected in series between power supply line PL2 and ground line SL, and diodes D5 and D6 connected in parallel with IGBT elements Q5 and Q6, respectively. The cathode of diode D5 is connected to the collector of IGBT element Q5, and the anode of diode D5 is connected to the emitter of IGBT element Q5. The cathode of diode D6 is connected to the collector of IGBT element Q6, and the anode of diode D6 is connected to the emitter of IGBT element Q6.

  W-phase arm 17 includes IGBT elements Q7 and Q8 connected in series between power supply line PL2 and ground line SL, and diodes D7 and D8 connected in parallel with IGBT elements Q7 and Q8, respectively. The cathode of diode D7 is connected to the collector of IGBT element Q7, and the anode of diode D7 is connected to the emitter of IGBT element Q7. The cathode of diode D8 is connected to the collector of IGBT element Q8, and the anode of diode D8 is connected to the emitter of IGBT element Q8.

  The intermediate point of each phase arm is connected to one end of each phase coil of motor generator MG1. That is, motor generator MG1 is a three-phase permanent magnet synchronous motor, and one end of each of three coils of U, V, and W phases is connected to the midpoint. The other end of the U-phase coil is connected to the connection node of IGBT elements Q3 and Q4. The other end of the V-phase coil is connected to a connection node of IGBT elements Q5 and Q6. The other end of the W-phase coil is connected to a connection node of IGBT elements Q7 and Q8.

  Other power switching elements such as power MOSFETs may be used in place of the above IGBT elements Q1 to Q8.

  Current sensor 24 detects the current flowing through motor generator MG1 as motor current value MCRT1, and outputs motor current value MCRT1 to control device 30.

  Inverter 22 is connected to power supply line PL2 and ground line SL. Inverter 22 converts the DC voltage output from boost converter 12 into a three-phase AC and outputs the same to motor generator MG2 driving wheel 2. Inverter 22 returns the electric power generated in motor generator MG2 to boost converter 12 along with regenerative braking. At this time, boost converter 12 is controlled by control device 30 to operate as a step-down circuit. Although the internal configuration of inverter 22 is not shown, it is similar to inverter 14, and detailed description will not be repeated.

  Control device 30 receives torque command values TR1 and TR2, motor rotation speeds MRN1 and MRN2, voltages VB and VH, current IB values, motor current values MCRT1 and MCRT2, and a start instruction IGON. Control device 30 outputs to boost converter 12 a boost instruction PWU, a step-down instruction PWD, and a signal CSDN instructing prohibition of operation.

  Further, control device 30 outputs drive instruction PWMI1 and regeneration instruction PWMC1 to inverter 14. Drive instruction PWMI1 is an instruction to convert a DC voltage, which is the output of boost converter 12, into an AC voltage for driving motor generator MG1. Regeneration instruction PWMC1 is an instruction for converting the AC voltage generated by motor generator MG1 into a DC voltage and returning it to boost converter 12 side.

  Similarly, control device 30 outputs drive instruction PWMI2 and regeneration instruction PWMC2 to inverter 22. Drive instruction PWMI2 is an instruction to convert a DC voltage into an AC voltage for driving motor generator MG2. Regenerative instruction PWMC2 is an instruction for converting the AC voltage generated by motor generator MG2 into a DC voltage and returning it to boost converter 12 side.

  Referring again to FIG. 1 again, the power supply device of the vehicle 100 is connected to the battery B, the power supply line PL1, and the load circuit 23, and is charged with the current C supplied from the power supply line PL1. And a connecting portion 40 that connects the battery B to the power supply line PL1. Connection portion 40 is electrically connected between battery B and power supply line PL1, and is electrically connected between battery B and power supply line PL1 and resistor R1 disposed at a position where heat transfer to battery B is possible. System main relay SMR1 connected in series with resistor R1 and system main relay SMR2 directly connecting battery B and power supply line PL1. Vehicle 100 further includes a control device 30 that turns on system main relay SMR2 after turning on system main relay SMR1 in response to a vehicle activation instruction IGON.

  Preferably, the power supply device of vehicle 100 further includes a temperature sensor 42 that detects the temperature of battery B and notifies the control device. Control device 30 maintains a state in which system main relay SMR1 is turned on and system main relay SMR2 is turned off until the temperature of battery B becomes higher than a predetermined temperature.

  Thereby, for example, when power is consumed by the load circuit 23 or the electric air conditioner 35, at this time, a current flows to the load circuit 23 or the electric air conditioner 35 via the resistor R1. Then, Joule heat is generated in the resistor R1. If this heat is transmitted to the battery B, the battery can be heated to an appropriate operating temperature at a low temperature without providing a special heater.

  If the resistor R1 and the system main relay are connected in series, the inrush current at start-up can be limited, but the resistor R1 is connected to the battery B side in terms of transferring the heat generated at this time to the battery B. It is preferable to connect.

Furthermore, the heat transfer to the battery B is improved by devising the arrangement of the resistor R1.
FIG. 2 is a diagram showing a configuration of the battery pack 49 in which the battery B of FIG. 1 is accommodated.

  Referring to FIG. 2, battery pack 49 includes a case 44 that is a battery cover, a battery B in which a large number of battery cells are arranged, a resistor R <b> 1, and a lower case 46.

As shown in FIG. 1, the resistor R <b> 1 is a resistor for limiting the current for charging the capacitors C <b> 1 and C <b> 2 so as not to become an overcurrent when the system is activated. For example, if this resistance is 100Ω and the battery voltage is 200V, the maximum value of the current can be suppressed to 2A. The maximum Joule heat is from I ² R to 400 W. If a heater of about 400 W is provided to heat the battery B, it can be used as a limiting resistor. That is, the heater and the limiting resistor can be used together.

  Preferably, the heat is easily transferred upward by the convection of warmed air, so that the resistor R1 is disposed at the bottom of the battery B.

  Preferably, the resistor R1 includes a plurality of resistors 48 distributed under the battery B. Normally, the resistor R1 is concentrated on the side of the system main relay SMR1, but is distributed below the battery B to warm the battery B.

FIG. 3 is a diagram illustrating a first modification of the resistor R1 of FIG.
As shown in FIG. 3, the resistor R <b> 1 may include a linear heating element R <b> 11 arranged along the battery B.

FIG. 4 is a diagram showing a second modification of the resistor R1 of FIG.
As shown in FIG. 4, the resistor R <b> 1 may include a planar heating element R <b> 21 arranged along the battery B. Various heaters are available as the linear heating element shown in FIG. 3 and the planar heating element shown in FIG.

  FIG. 5 is a functional block diagram of the control device 30 of FIG. The control device 30 can be realized by software or hardware.

  1 and 5, control device 30 includes a boost converter control unit 31 that controls boost converter 12, an MG1 inverter control unit 32 that controls motor generator MG1, and an MG2 that controls motor generator MG2. An inverter control unit 33 and a relay control unit 34 that controls the connection unit 40 are included.

  Boost converter control unit 31 outputs boost instruction PWU and step-down instruction PWD to boost converter 12 in FIG. Further, the MG1 inverter control unit 32 outputs a drive instruction PWMI1 and a regeneration instruction PWMC1 to the inverter 14 based on the torque command value TR1 and the motor rotational speed MRN1. Further, the MG2 inverter control unit 33 outputs a drive instruction PWMI2 and a regeneration instruction PWMC2 to the inverter 14 based on the torque command value TR2 and the motor rotational speed MRN2.

  Relay control unit 34 outputs control signals CONT1 to CONT3 to system main relays SMR1 to SMR3, respectively. When battery temperature TB is within an appropriate temperature range, relay control unit 34 conducts system main relays SMR1 and SMR3 in response to activation instruction IGON, and precharges capacitors C1 and C2 to complete precharging. Then, after system main relay SMR2 is turned on, system main relay SMR1 is opened. At this time, connection unit 40 is in a state in which current from battery B can be supplied to motor generators MG1 and MG2.

  On the other hand, when battery temperature TB is lower than the appropriate temperature range, relay control unit 34 conducts system main relays SMR1, SMR3 in response to activation instruction IGON, and the precharge of capacitors C1, C2 is completed. It is determined later whether the battery temperature TB has risen to an appropriate temperature range. Here, if the temperature rise is insufficient, the relay control unit 34 determines the state of the connection unit 40 so that power is further supplied to the electric air conditioner 35 and the load circuit 23 via the system main relay SMR1 and the resistor R1. To maintain. When the battery temperature reaches an appropriate temperature range, relay control unit 34 opens system main relay SMR1 after conducting system main relay SMR2.

  FIG. 6 is a flowchart showing a control structure of processing executed by the control device 30. The processing of this flowchart is called and executed after a predetermined time elapses from a predetermined main routine or whenever a predetermined condition is satisfied.

  Referring to FIGS. 1 and 6, first, when the process is started, control device 30 determines whether or not an activation instruction is given from the driver in step S1. That is, control device 30 determines whether or not activation instruction IGON has changed from the off state to the on state.

  In step S1, when the start instruction from the driver is not given, the process proceeds to step S8, and the control is moved to the main routine. On the other hand, when the activation instruction is given from the driver, the process proceeds to step S2.

  In step S2, control device 30 changes system main relay SMR3 from the off state to the on state. Subsequently, in step S3, control device 30 changes system main relay SMR1 from the off state to the on state. Then, supply of current from the battery B to the capacitors C1 and C2 via the resistor R1 is started.

  As a result of supplying current to the capacitor C2 via the resistor R1, the power supply line PL1, and the diode D1, the voltage VH gradually increases. In step S4, it is determined whether or not the precharge of the capacitor C2 has been completed. That is, it is determined whether or not voltage VH has risen to near battery voltage VB and the voltage difference has become smaller than threshold value V0.

  If the voltage difference between the voltage VH and the battery voltage VB is greater than the threshold value V0, step S4 is executed again. Thus, a time is waited until the voltage difference between voltage VH and battery voltage VB becomes smaller than threshold value V0. In place of this step S4, a step of waiting until the precharge time which has been experimentally obtained in advance may elapse may be included.

  When the voltage difference between voltage VH and battery voltage VB is smaller than threshold value V0, the process proceeds from step S4 to step S5. In step S5, it is determined whether or not battery temperature TB is higher than threshold temperature T0. If the battery temperature TB is too low due to the characteristics of the battery, the output decreases and the output of the battery B cannot be increased too much. Therefore, it is necessary to warm the battery B so that the battery temperature TB becomes higher than the threshold temperature T0. It becomes.

  In step S5, the state of connection 40 is a state in which system main relays SMR1 and SMR3 are turned on and current from the battery is supplied to the load circuit via resistor R1.

  Therefore, in this state, when the electric air conditioner 35 and the load circuit 23 operate according to the switch operation and the accelerator operation from the driver, Joule heat is generated at the resistor R1 and the battery B is warmed.

  In step S5, if TB> T0 does not hold, the state of connection 40 is maintained so that electric power is supplied to electric air conditioner 35 and load circuit 23 via system main relay SMR1 and resistor R1. When TB> T0 is established, the process proceeds from step S5 to step S6.

  In step S6, control device 30 changes system main relay SMR2 from the off state to the on state. In step S7, control device 30 changes system main relay SMR1 from the on state to the off state.

  When the process of step S7 is completed, control is transferred to the main routine in step S8.

  Preferably, the heat generated by the resistor R1 is transferred to the battery B as necessary by changing the direction of the air flow.

  FIG. 7 is a schematic diagram for explaining air flow control between the resistor R1 and the battery B.

  Referring to FIG. 7, the vehicle power supply device includes a temperature sensor 42 that detects the temperature of battery B and notifies control device 30, and passages 50, 54, and 56 that pass cooling air in the order of battery B and resistance. And a blower 52 provided in the passage.

  When the temperature of battery B is higher than a predetermined temperature and cooling of battery B is necessary, control device 30 uses fan 52 to blow in the direction indicated by arrow F1.

  When the temperature of the battery B is lower than the predetermined temperature, the control device 30 controls the blower 52 in the state in which the system main relay SMR1 is turned on and the current flows through the resistor R1, and resists in the direction indicated by the arrow F2. The wind is caused to flow backward from R1 toward battery B. Thereby, the heat generated by the resistor R1 is transmitted to the battery B using wind as a medium.

FIG. 8 is a diagram showing a blowing direction when normal battery cooling is performed.
As shown by the arrows in FIG. 8, when the battery is cooled, the air sucked from the passage 50 is sent to the passage 54 by the blower 52. Air is blown from the passage 54 toward the upper surface of the battery B inside the case 44. Inside the case 44, wind flows from top to bottom along the longitudinal side surface of the battery B. The wind that reaches the lower surface of the battery is discharged through the passage 56.

FIG. 9 is a diagram illustrating a blowing direction when battery temperature rise is performed.
As shown by the arrows in FIG. 9, when the battery is warmed, the blowing direction of the blower 52 is reversed. Then, the air sucked from the passage 56 is sent to the inside of the case 44 and toward the lower surface of the battery B. Inside the case 44, the wind flows from bottom to top along the side surface of the battery B in the longitudinal direction. The wind is sucked into the blower 52 through the passage 54 and further discharged through the passage 50.

  In this way, by switching the direction of the air flow based on the battery temperature, the heat generated by the resistor R1 is transmitted to the battery B when necessary, and not transmitted to the battery B when unnecessary (during cooling). it can.

[Embodiment 2]
In Embodiment 1, the case where there is one battery which is a power storage device is shown. In the second embodiment, a vehicle equipped with a plurality of batteries will be described.

  FIG. 10 is a diagram illustrating a main configuration of the vehicle 110 according to the second embodiment. The vehicle 110 is a hybrid vehicle that uses both a motor and an engine for driving the vehicle. However, the present invention is similarly applied to an electric vehicle, a fuel cell vehicle, and the like in which wheels are driven by a motor to which a plurality of batteries are applied. Can be applied.

  Referring to FIG. 10, vehicle 110 includes batteries BA and BB, connecting portions 40A and 40B, boost converters 12A and 12B, smoothing capacitors C1A, C1B and C2, and voltage sensors 13, 21A and 21B. Load circuit 23, engine 4, motor generators MG <b> 1 and MG <b> 2, power split mechanism 3, wheels 2, and control device 130 are included.

  Since load circuit 23, engine 4, motor generators MG1 and MG2, power split mechanism 3 and wheels 2 are the same as in vehicle 100 of the first embodiment described in FIG. 1, detailed description thereof will not be repeated.

  Vehicle 100 further includes power line PL1A, PL1B, PL2, ground line SL, voltage sensor 10A for detecting voltage VBA between terminals of battery BA, current sensor 11A for detecting current IBA flowing through battery BA, And a temperature sensor 42A for detecting the temperature of the battery BA. Vehicle 100 further includes a voltage sensor 10B that detects a voltage VBB between terminals of battery BB, a current sensor 11B that detects a current IBB flowing through battery BB, and a temperature sensor 42B that detects the temperature of battery BB.

For example, a secondary battery such as a lead storage battery, a nickel metal hydride battery, or a lithium ion battery can be used as the batteries BA and BB. The connection unit 40A is a system connected between the negative electrode of the battery BA and the ground line SL. Main relay SMR3A, system main relay SMR2A connected between the positive electrode of battery B and power supply line PL1A, and resistor R1A connected in series and system main relay SMR1A connected in parallel with system main relay SMR2A . System main relays SMR1A to SMR3A are controlled to be in a conductive / nonconductive state in accordance with control signals CONT1A to CONT3A supplied from control device 130, respectively.

  Capacitor C1A smoothes the voltage across terminals of battery BA when system main relays SMR1A to SMR3A are on. Capacitor C1A is connected between power supply line PL1A and ground line SL.

  Capacitor C1B smoothes the voltage across terminals of battery BB when system main relays SMR1B to SMR3B are on. Capacitor C1B is connected between power supply line PL1B and ground line SL.

  The voltage sensor 21A detects the voltage VLA across the capacitor C1A and outputs it to the control device 130. Boost converter 12A boosts the voltage across terminals of capacitor C1A. Voltage sensor 21B detects voltage VLB across capacitor C1B and outputs it to control device 130. Boost converter 12B boosts the voltage across terminals of capacitor C1B.

  Capacitor C2 smoothes the voltage boosted by one or both of boost converters 12A and 12B. The voltage sensor 13 detects the inter-terminal voltage VH of the smoothing capacitor C2 and outputs it to the control device 130.

  Boost converter 12A is parallel to reactor L1A having one end connected to power supply line PL1A, IGBT elements Q1A and Q2A connected in series between power supply line PL2 and ground line SL, and IGBT elements Q1A and Q2A, respectively. And diodes D1A and D2A connected to each other.

  Reactor L1A has the other end connected to the emitter of IGBT element Q1A and the collector of IGBT element Q2A. The cathode of diode D1A is connected to the collector of IGBT element Q1A, and the anode of diode D1A is connected to the emitter of IGBT element Q1A. The cathode of diode D2A is connected to the collector of IGBT element Q2A, and the anode of diode D2A is connected to the emitter of IGBT element Q2A.

  Boost converter 12B is parallel to reactor L1B having one end connected to power supply line PL1B, IGBT elements Q1B and Q2B connected in series between power supply line PL2 and ground line SL, and IGBT elements Q1B and Q2B. And diodes D1B and D2B connected to each other.

  Reactor L1B has the other end connected to the emitter of IGBT element Q1B and the collector of IGBT element Q2B. The cathode of diode D1B is connected to the collector of IGBT element Q1B, and the anode of diode D1B is connected to the emitter of IGBT element Q1B. The cathode of diode D2B is connected to the collector of IGBT element Q2B, and the anode of diode D2B is connected to the emitter of IGBT element Q2B.

  Control device 130 receives torque command values TR1 and TR2, motor rotation speeds MRN1 and MRN2, voltages VB and VH, current IB values, motor current values MCRT1 and MCRT2, and a start instruction IGON. Controller 130 outputs boost instruction PWUA and step-down instruction PWDA to boost converter 12A, and outputs boost instruction PWUB and step-down instruction PWDB to boost converter 12B.

  Further, control device 130 outputs drive instruction PWMI1 and regeneration instruction PWMC1 to inverter 14. Drive instruction PWMI1 is an instruction for converting a DC voltage, which is an output of boost converter 12, into an AC voltage for driving motor generator MG1. Regeneration instruction PWMC1 is an instruction for converting the AC voltage generated by motor generator MG1 into a DC voltage and returning it to boost converter 12 side.

  Similarly, control device 130 outputs drive instruction PWMI2 and regeneration instruction PWMC2 to inverter 22. Drive instruction PWMI2 is an instruction to convert a DC voltage into an AC voltage for driving motor generator MG2. Regenerative instruction PWMC2 is an instruction for converting the AC voltage generated by motor generator MG2 into a DC voltage and returning it to boost converter 12 side.

  Referring to FIG. 10 again, the vehicle power supply device disclosed in the second embodiment includes batteries BA and BB, and power supply lines PL1A provided corresponding to batteries BA and BB, respectively. PL1B includes a capacitor C2 connected to a load circuit and supplied with current from power supply lines PL1A and PL1B and charged, and connections 40A and 40B connecting batteries BA and BB to power supply lines PL1A and PL1B, respectively.

  Connection portion 40A is electrically connected between corresponding battery BA and corresponding power supply line PL1A, and has a resistance R1A arranged at a position where heat can be transferred to corresponding battery BA, battery BA and the power supply line. System main relay SMR1A electrically connected in series with resistor R1A between PL1A and system main relay SMR2A directly connecting battery BA and power supply line PL1A are included.

  Connection portion 40B is electrically connected between corresponding battery BB and corresponding power supply line PL1B, and is disposed at a position where heat can be transferred to corresponding battery BB, battery BB and the power supply line System main relay SMR1B electrically connected in series with resistor R1B between PL1B and system main relay SMR2B directly connecting battery BB and power supply line PL1B are included.

  In response to the vehicle activation instruction IGON, the vehicle power supply device causes the system main relay SMR1A to turn on after the system main relay SMR1A is turned on, and turns on the system main relay SMR2B after turning on the system main relay SMR1B. 130 is further provided.

  Regarding the arrangement and shape of the resistors R1A and R1B, the arrangement and shape described in FIG. 2 can be applied to each battery pack of the batteries BA and BB. As in the first embodiment, the shapes shown in FIGS. 3 and 4 can be applied to the shapes of the resistors R1A and R1B. Further, as described with reference to FIG. 7, each battery BA, BB may employ a cooling structure in which the direction of air flow is reversed between when the battery is heated and when it is cooled.

  FIG. 11 is a functional block diagram of the control device 130 of FIG. The control device 130 can be realized by software or hardware.

  Referring to FIGS. 10 and 11, control device 30 includes boost converter control units 131A and 131B for controlling boost converters 12A and 12B, an MG1 inverter control unit 132 for controlling motor generator MG1, and a motor generator MG2. MG2 inverter control unit 133 that controls the relay and a relay control unit 134 that controls the connection units 40A and 40B.

  Boost converter control unit 131A outputs boost instruction PWUA and step-down instruction PWDA to boost converter 12A in FIG. Further, MG1 inverter control unit 132 outputs drive instruction PWMI1 and regeneration instruction PWMC1 to inverter 14 based on torque command value TR1 and motor rotation speed MRN1. Further, the MG2 inverter control unit 133 outputs a drive instruction PWMI2 and a regeneration instruction PWMC2 to the inverter 22 based on the torque command value TR2 and the motor rotational speed MRN2.

  Relay control unit 134 outputs control signals CONT1A to CONT3A to system main relays SMR1A to SMR3A, respectively. Relay control unit 134 outputs control signals CONT1B to CONT3B to system main relays SMR1B to SMR3B, respectively.

  If battery temperature TBA or TBB is within an appropriate temperature range, relay control unit 34 conducts system main relays SMR1A, SMR3A, SMR1B, and SMR3B in response to a start instruction IGON, and precharges capacitors C1A, C1B, and C2. When precharging is completed, system main relays SMR2A and SMR2B are turned on and then system main relays SMR1A and SMR1B are opened. At this time, connection units 40A and 40B are in a state in which current from batteries BA and BB can be supplied to motor generators MG1 and MG2.

  On the other hand, when battery temperature TBA or TBB is lower than the appropriate temperature range, relay control unit 134 turns on system main relays SMR1 and SMR3 in response to activation instruction IGON, and capacitors C1 and C2 are precharged. After completion, it is determined whether the battery temperature TB has risen to an appropriate temperature range.

  Here, if the increase in battery temperature TBA is insufficient, relay control unit 134 causes connection unit 40 to repeat charging / discharging between battery BA and battery BB via system main relay SMR1A and resistor R1A. In addition to setting the state, the boost converter control units 131A and 131B are instructed.

  When battery temperature TBA reaches an appropriate temperature range, relay control unit 134 opens system main relay SMR1A after conducting system main relay SMR2A.

  If the rise in battery temperature TBB is insufficient, relay control unit 134 determines the state of connection unit 40 so that charging / discharging is repeated between battery BA and battery BB via system main relay SMR1B and resistor R1B. Is set and the boost converter control units 131A and 131B are instructed.

  When battery temperature TBB reaches an appropriate temperature range, relay control unit 134 turns on system main relay SMR2B and then opens system main relay SMR1B.

  FIG. 12 is a flowchart illustrating a control structure of processing executed by the control device 130. The processing of this flowchart is called and executed after a predetermined time elapses from a predetermined main routine or whenever a predetermined condition is satisfied. In addition, since the same process is performed about connection part 40A, 40B, the flowchart about connection part 40A is shown typically. In the flowchart of the control of the connecting portion 40B, the system main relays SMR1A to SMR3A, the battery voltage VBA, and the temperature TBA in FIG. Therefore, description of the connection unit 40B using the flowchart will not be repeated.

  Referring to FIGS. 10 and 12, first, when the process is started, control device 130 determines whether or not an activation instruction is given from the driver in step S11. That is, it is determined whether or not the activation instruction IGON has changed from the off state to the on state.

  In step S11, when the start instruction from the driver is not given, the process proceeds to step S20, and the control is moved to the main routine. On the other hand, when the activation instruction is given from the driver, the process proceeds to step S12.

  In step S12, control device 130 changes system main relay SMR3A from the off state to the on state. Subsequently, in step S13, control device 30 changes system main relay SMR1A from the off state to the on state. Then, supply of current from the battery BA to the capacitors C1A and C2 is started via the resistor R1A.

  As a result of supplying current to the capacitor C2 via the resistor R1A, the power supply line PL1A, and the diode D1A, the voltage VH gradually increases. In step S14, it is determined whether or not the precharge of the capacitor C2 has been completed. That is, it is determined whether or not voltage VH has risen to near battery voltage VBA and the voltage difference for current flowing through diode D1A has become smaller than threshold value V0. Since capacitor C2 is charged by diode D1A and diode D1B, voltage VH rises to near the higher voltage of batteries BA and BB.

  If VBA−VH <V0 is not established, the current charged from the battery BA to the capacitor C2 is still large, so that if the system main relay SMR2 is turned on, an overcurrent may flow, so step S14 is executed again. Thus, a time is waited until the voltage difference between voltage VH and battery voltage VBA becomes smaller than threshold value V0. Instead of this step S14, a step of waiting until the precharge time that has been experimentally obtained in advance may elapse may be included. Note that when the voltage of the battery BB is higher than that of the battery BA and VH> VBA, a reverse voltage is applied to the diode D1A, so no overcurrent flows, so there is no problem.

  If VBA−VH <V0 is established, the process proceeds from step S14 to step S15. In step S15, it is determined whether or not battery temperature TBA is higher than threshold temperature T0. If the battery temperature TBA is too low, the output of the battery BA cannot be increased so much that it is necessary to warm the battery BA so that the battery temperature TBA becomes higher than the threshold temperature T0.

  If TBA> T0 does not hold in step S15, the process proceeds from step S15 to step S16. In step S16, it is determined whether or not the current consumption of the load circuit 23 is smaller than a predetermined value. When a predetermined value of current is flowing through the load circuit 23, there is no problem in heating the battery BA because appropriate heat is generated in the resistor R1A. However, when the current flowing through the load circuit 23 is small, the current flowing through the resistor R1A is small, and therefore the heat generation at the resistor R1A is small. Therefore, it is necessary to positively flow current through the resistor R1A.

  Therefore, if the current consumption of the load circuit 23 is smaller than the predetermined value, the process proceeds from step S16 to step S17. On the other hand, if the current consumption of the load circuit 23 is equal to or greater than the predetermined value, the process proceeds from step S16 to step S15.

  In step S17, in order to increase the current of the resistor R1A without increasing the current of the load circuit 23, the process of controlling the boost converters 12A and 12B so as to charge and discharge the current between the battery BA and the battery BB. Is executed. For example, boost converter 12A is controlled to repeat charging and discharging in a control (current control mode) in which the charge / discharge current is set to a target value, and boost converter 12B keeps voltage VH constant by reducing voltage VH to the target value. Control (voltage control mode) may be performed. When the process of step S17 ends, the process proceeds to step S15.

  If TBA> T0 is satisfied in step S15, the process proceeds from step S15 to step S18.

  In step S18, control device 130 changes system main relay SMR2A from the off state to the on state. In step S19, control device 130 changes system main relay SMR1A from the on state to the off state.

  When the process of step S19 ends, control is transferred to the main routine in step S20.

  FIG. 13 is an operation waveform diagram for explaining an operation when the battery temperature is higher than a predetermined temperature when the vehicle is started.

  Referring to FIGS. 10 and 13, it is assumed that battery temperature TBA is already equal to or higher than threshold value T0 (TBA> T0) before time t1, and it is not necessary to warm the battery.

  At time t1, activation instruction IGON changes from the off state to the on state. In response, system main relays SMR3A and SMR3B change from the off state to the on state. At time t2, system main relays SMR1A and SMR1B change from the off state to the on state.

  Then, since a charging current flows into the capacitor C2, the current IBA of the battery BA first reaches a maximum value and then decreases as time elapses. On the other hand, the voltage VH approaches the battery voltage VB (the higher of the voltages VBA and VBB) as charging progresses. During this time, current is supplied from the battery BA to the capacitor C2 via the resistor R1A.

  When precharging of capacitor C2 is completed at time t3, system main relays SMR2A and SMR2B change from the off state to the on state. At time t4, system main relays SMR1A and SMR1B change from the on state to the off state, and the activation of the power supply system is completed.

  FIG. 14 is an operation waveform diagram for explaining an operation when the battery temperature is lower than a predetermined temperature at the time of starting the vehicle.

  Referring to FIGS. 10 and 14, it is assumed that battery temperature TBA is lower than threshold value T0 (TBA <T0) before time t11 and the battery needs to be warmed.

  At time t11, the activation instruction IGON changes from the off state to the on state. In response, system main relays SMR3A and SMR3B change from the off state to the on state. At time t12, system main relays SMR1A and SMR1B change from the off state to the on state.

  Then, since a charging current flows into the capacitor C2, the current IBA of the battery BA first reaches a maximum value and then decreases as time elapses. On the other hand, the voltage VH approaches the battery voltage VB (the higher of the voltages VBA and VBB) as charging progresses. During this time, current is supplied from the battery BA to the capacitor C2 via the resistor R1A.

  Since heat is also generated by the resistors R1A and R1B due to the precharge current of the capacitor C2, the batteries BA and BB can be expected to rise somewhat.

  At time t3, when the precharge of the capacitor C2 is completed, it is determined whether or not the temperature of each battery has exceeded the threshold value T0, and if so, the system main relay of the battery that has exceeded the temperature is switched and connected via a resistor. The settings of the connecting portions 40A and 40B are changed so that current can be supplied or charged without any change. For the battery whose battery temperature does not exceed the threshold value, the settings of the connecting portions 40A and 40B are maintained so that current is supplied or charged through the resistor.

  Between times t3 and t14, control device 130 performs a first control cycle CY1 for discharging battery BA to charge battery BB and a second control cycle CY2 for discharging battery BB to charge battery BA. Make it run repeatedly. If current is consumed by the load circuit 23, sufficient heat is generated by the resistor R1A or R1B, so that such processing is unnecessary. Therefore, when the power consumption of the load circuit 23 is less than the predetermined value and the temperature of the batteries BA and BB is lower than the predetermined temperature, the control device 130 determines that the first control cycle CY1 and the second control cycle CY2 Repeatedly.

  At this time, in order to increase the current of the resistor R1A without increasing the current of the load circuit 23, a process for controlling the boost converters 12A and 12B so as to charge and discharge the current between the battery BA and the battery BB is performed. Executed. For example, boost converter 12A is controlled to repeat charging and discharging in a control (current control mode) in which the charge / discharge current is set to a target value, and voltage booster 12B is set with voltage VH set to the target value. Control (voltage control mode) may be performed so as to keep VH constant. At this time, the current IBA in FIG. 14 repeats the plus direction (discharge) and the minus direction (charge), and the voltage VH slightly varies accordingly.

  When the battery temperature TBA reaches the threshold value T0 at time t14, the control for repeating charging and discharging between the batteries is stopped, the current value IBA becomes zero, and the voltage VH converges to a constant value.

  At time t15, system main relays SMR2A and SMR2B change from the off state to the on state. At time t16, system main relays SMR1A and SMR1B change from the on state to the off state, and the start-up of the power supply system is completed.

  As described above, according to the present embodiment, the battery can be heated using the precharge current of the capacitor at the time of starting the power supply system. Further, by combining the resistor for limiting the inrush current during precharging and the heater for raising the temperature of the battery, cost reduction and space saving can be realized. Further, when the temperature rise is insufficient, the battery can be further heated by actively passing a current through the resistor.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure which shows the main structures of the vehicle 100 of Embodiment 1 of this invention. It is a figure which shows the structure of the battery pack 49 in which the battery B of FIG. 1 was accommodated. FIG. 6 is a diagram showing a first modification of the resistor R1 of FIG. FIG. 10 is a diagram illustrating a second modification of the resistor R1 in FIG. 2. It is a functional block diagram of the control apparatus 30 of FIG. 3 is a flowchart illustrating a control structure of processing executed by a control device 30. It is the schematic for demonstrating the ventilation control between resistance R1 and the battery B. FIG. It is a figure which shows the ventilation direction in case normal battery cooling is performed. It is a figure which shows the ventilation direction in case battery temperature rising is performed. It is a figure which shows the main structures of the vehicle 110 of Embodiment 2. FIG. It is a functional block diagram of the control apparatus 130 of FIG. It is a flowchart which shows the control structure of the process which the control apparatus 130 performs. It is an operation waveform diagram for explaining operation when the battery temperature is higher than a predetermined temperature when the vehicle is started. It is an operation waveform diagram for explaining operation when the battery temperature is lower than a predetermined temperature when the vehicle is started.

Explanation of symbols

  2 wheel, 3 power split mechanism, 4 engine, 10, 10A, 10B, 13, 21, 21, A, 21B voltage sensor, 11, 11A, 11B, 24 current sensor, 12, 12A, 12B boost converter, 14, 22 inverter, 15 U-phase arm, 16 V-phase arm, 17 W-phase arm, 23 load circuit, 30, 130 control device, 31, 131A, 131B boost converter control unit, 32, 132 MG1 inverter control unit, 33, 133 MG2 inverter Control unit, 34, 134 relay control unit, 35 electric air conditioner, 40, 40A, 40B connection unit, 42, 42A, 42B temperature sensor, 44 case, 46 lower case, 48 resistor, 49 battery pack, 50, 54, 56 passage , 52 Blower, 100, 110 Vehicle, B, BA, BB Battery, C1, C1A, C1B, C2 capacitors, D1-D8, D1A, D2A, D1B, D2B diode, L1, L1A, L1B reactor, MG1, MG2 motor generator, PL1, PL1A, PL1B, PL2 power supply line, Q1-Q8 , Q1A, Q2A, Q1B, Q2B IGBT element, R1, R1A, R1B resistance, R11 linear heating element, R21 planar heating element, SMR1-SMR3, SMR1A-SMR3A, SMR1B-SMR3B system main relay.

Claims (9)

A power storage device;
A power line,
A capacitor connected to a load circuit and charged by being supplied with current from the power line;
A connecting portion for connecting the power storage device to the power line,
The connecting portion is
A resistor electrically connected between the power storage device and the power supply line, and disposed at a position capable of transferring heat to the power storage device;
A first relay electrically connected in series with the resistor between the power storage device and the power line;
A second relay for directly connecting the power storage device and the power line;
A power supply device for a vehicle, further comprising: a control device that turns on the second relay after turning on the first relay in response to a vehicle activation instruction.   The power supply device for a vehicle according to claim 1, wherein the resistor is disposed below the power storage device.   2. The power supply device for a vehicle according to claim 1, wherein the resistor includes a plurality of resistors distributed in a lower portion of the power storage device.   The power supply device for a vehicle according to claim 1, wherein the resistor includes a linear heating element disposed along the power storage device.   The power supply device for a vehicle according to claim 1, wherein the resistor includes a planar heating element disposed along the power storage device. The power supply device of the vehicle is
A temperature sensor for detecting the temperature of the power storage device and notifying the control device;
2. The control device according to claim 1, wherein the control device maintains a state in which the first relay is made conductive and the second relay is made non-conductive until the temperature of the power storage device becomes higher than a predetermined temperature. Vehicle power supply. The power supply device of the vehicle is
A temperature sensor for detecting the temperature of the power storage device and notifying the control device;
A passage for passing cooling air in the order of the power storage device and the resistance;
A fan provided in the passage,
2. The power supply device for a vehicle according to claim 1, wherein when the temperature of the power storage device is lower than a predetermined temperature, the control device controls the blower to cause a wind to flow backward from the resistance toward the power storage device. A plurality of power storage devices;
A plurality of power supply lines provided corresponding to each of the plurality of power storage devices;
A capacitor connected to a load circuit and charged with current supplied from the plurality of power supply lines;
A plurality of connection portions respectively connecting the plurality of power storage devices to the plurality of power supply lines,
Each of the plurality of connection portions is
A resistor electrically connected between a corresponding power storage device and a corresponding power supply line, and disposed at a position capable of transferring heat to the corresponding power storage device;
A first relay electrically connected in series with the resistor between the power storage device and the power line;
A second relay for directly connecting the power storage device and the power line;
A power supply device for a vehicle, further comprising: a control device that turns on the second relay after turning on the first relay in response to a vehicle activation instruction. The control device is configured to discharge a first power storage device of the plurality of power storage devices and charge a second power storage device of the plurality of power storage devices; and the second power storage A second control cycle for discharging the device and charging the first power storage device is executable,
When the power consumption of the load circuit is less than a predetermined value and the temperature of the power storage device is lower than a predetermined temperature, the control device turns on the first relay and turns off the second relay The power supply device for a vehicle according to claim 8, wherein the first control cycle and the second control cycle are repeatedly executed in a state of being set to the above.

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