JP2017103950A - Power supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply device capable of preventing degradation of a component which is commonly used when performing outside charge and when supplying the electric power to an electric load.SOLUTION: When a charge relay CHR is in operation for pre-charging a capacitor (YES in S100), and when a state that a current IB exceeds a threshold value α continues until a predetermined time elapses (YES in S102), an ECU (electronic control unit) controls a step (S104) to set the charge relay CHR to OFF, and a step (S106) to prohibit the operation of the charge relay CHR and to permit operation of a system main relay SMR.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power supply device for a vehicle, and more particularly to control of a power supply device including a charging device capable of charging a power storage device using an AC power supply.

  In International Publication No. 2013/042166 (Patent Document 1), a system main relay provided between an electric load such as a motor for driving a vehicle and a battery, and charging of the battery using an AC power source outside the vehicle ( Hereinafter, a vehicle equipped with a power supply device including a charging relay provided between a charging device capable of performing external charging) and a battery is disclosed. In this vehicle, a current limiting resistor for the system main relay for precharging the capacitor included in the circuit on the electric load side and a charging relay for precharging the capacitor included in the circuit on the charging device side are provided. A common resistor is used as the current limiting resistor.

International Publication No. 2013/042166

  However, when precharging the capacitor on the charging device side in order to perform external charging, an abnormality such as a short circuit may occur in the circuit on the charging device side, and the current limiting resistor may deteriorate early due to overcurrent. is there. In this case, if the capacitor on the electric load side deteriorates until it cannot be precharged, the system main relay provided between the electric load and the battery cannot be brought into conduction, and power is supplied to the electric load. There are cases where it is impossible.

  The present invention has been made to solve the above-described problems, and provides a power supply device for a vehicle that suppresses deterioration of components that are commonly used during external charging and power supply to an electric load. is there.

  A vehicle according to an aspect of the present invention includes a power storage device that supplies power to an electric load, a resistor that has one end connected to a first node connected to either the positive electrode or the negative electrode of the power storage device, and the electric load A first relay provided between the first power line connected to the first power line, and a second relay provided in parallel with the first relay between the second node connected to the other end of the resistor and the first power line. A third relay provided between a first node and a second power line connected to the charging device, a first relay, a charging device for charging the power storage device using an external power source, A charging-side relay device including a fourth relay provided in parallel with the third relay between the two nodes and the second power line, and one end connected to the second power line, and parallel to the charging device with respect to the power storage device Capacitor connected to the load relay device And a control device for controlling the operation of the pre-charge side relay device. The control device starts precharging the capacitor that turns on the fourth relay before turning on the third relay, and then the current of the power storage device is equal to or greater than the threshold until a predetermined time elapses. When this state continues, the charging device and the power storage device are electrically disconnected from each other to prohibit the operation of the charging-side relay device and to permit the operation of the load-side relay device.

  In this case, after the precharge of the capacitor is started, if the current of the power storage device continues to exceed the threshold until a predetermined time elapses, the charging device and the power storage device are electrically connected. The deterioration of the resistor can be suppressed by setting it to the blocking state. Furthermore, the deterioration of the resistor can be suppressed by prohibiting the operation of the charging side relay device thereafter. In addition, by permitting the operation of the load-side relay device, the electric power of the power storage device can be supplied to the electric load, so that the operation of the electric load can be continued.

  According to the present invention, it is possible to provide a power supply device for a vehicle that suppresses deterioration of components that are commonly used during external charging and power supply to an electric load.

1 is an overall configuration diagram of a vehicle according to an embodiment. It is a flowchart which shows an example of the control processing performed by ECU. It is a timing chart for demonstrating operation | movement of ECU.

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

  FIG. 1 is an overall configuration diagram of a vehicle according to the present embodiment. In the present embodiment, vehicle 1 is a hybrid vehicle. Vehicle 1 includes motor generators MG1, MG2, system main relay SMR, charging relay CHR, inverter 20, engine 30, power split device 40, drive wheels 50, boost converter 60, battery 70, A charging device 80, an inlet 90, and an ECU (Electronic Control Unit) 200 are provided.

  Motor generators MG 1, MG 2 and engine 30 are connected to power split device 40. Vehicle 1 travels by driving force from at least one of engine 30 and motor generator MG2.

  The power generated by engine 30 is divided by power split device 40 into a path that is transmitted to drive wheels 50 and a path that is transmitted to motor generator MG1.

  Each of motor generators MG1 and MG2 is an AC rotating electric machine, for example, a three-phase AC rotating electric machine including a rotor in which a permanent magnet is embedded. Electric power is generated by motor generator MG1 using the power of engine 30 divided by power split device 40. AC power generated by motor generator MG1 is converted into DC power by inverter 20 and supplied to battery 70 via boost converter 60.

  Motor generator MG2 generates driving force using at least one of the electric power supplied from battery 70 and the electric power generated by motor generator MG1. The driving force of motor generator MG2 is transmitted to driving wheel 50. When the vehicle is braked, etc., motor generator MG2 is driven by drive wheels 50, and motor generator MG2 operates as a generator. Thus, motor generator MG2 operates as a regenerative brake that converts braking energy into electric power. AC power generated by motor generator MG2 is converted into DC power in inverter 20 and supplied to battery 70 via boost converter 60.

  Power split device 40 includes a planetary gear mechanism having a sun gear, a pinion gear, a carrier, and a ring gear. The pinion gear meshes with each of the sun gear and the ring gear. The carrier supports the pinion gear so as to be capable of rotating, and is connected to the crankshaft of the engine 30. The sun gear is coupled to the rotation shaft of motor generator MG1. Ring gear is coupled to the rotation shaft of motor generator MG2 and the output shaft connected to drive wheel 50.

  The battery 70 is a direct current power source constituted by a secondary battery such as a nickel metal hydride battery or a lithium ion battery. The battery 70 is configured by connecting a plurality of battery cells in series, for example. Battery 70 is connected to boost converter 60 via system main relay SMR.

  System main relay SMR includes a relay SMRB, a relay SMRP, and a relay SMRG. Opening / closing of each of relay SMRB, relay SMRP, and relay SMRG is controlled based on a signal from ECU 200.

  The first node 72 is connected to the negative electrode of the battery 70. One end of a precharging resistor R is connected to the first node 72. Relay SMRG is provided between first node 72 and negative electrode line NL1 connected to boost converter 60. Between the second node 74 connected to the other end of the resistor R and the negative electrode line NL1, a relay SMRP is provided in parallel with the relay SMRG.

  A third node 76 is connected to the positive electrode of the battery 70. Relay SMRB is provided between third node 76 and positive line PL1 connected to boost converter 60.

  With such a configuration, relay SMRB switches connection and disconnection of the path between positive line PL1 and positive electrode of battery 70. Relay SMRP switches connection and disconnection of a path between negative electrode line NL1 and negative electrode of battery 70 via precharge resistor R. Relay SMRG switches connection and disconnection of a path between negative electrode line NL1 and the negative electrode of battery 70 without passing through precharge resistor R.

  Capacitor C <b> 1 is connected to battery 70 in parallel with boost converter 60. Capacitor C <b> 1 smoothes voltage VB of battery 70 and supplies it to boost converter 60.

  When a control signal is received from ECU 200 to turn on system main relay SMR, relay SMRB and relay SMRG are finally turned on, so that battery 70 and boost converter 60 are electrically connected. Connected state. At this time, before the relay SMRG is turned on after the relay SMRB is turned on, the relay SMRP is temporarily turned on to prevent the capacitor C1 from being turned on in order to prevent an excessive current from flowing. Charging is performed.

  Boost converter 60 boosts the voltage supplied from battery 70 based on a signal from ECU 200 and supplies the boosted voltage to inverter 20. Inverter 20 converts the DC power boosted by boost converter 60 based on a signal from ECU 200 into AC power and outputs the AC power to each of motor generators MG1 and MG2. Boost converter 60 includes a switching element such as an IGBT (Insulated Gate Bipolar Transistor) element and a diode, and operates according to a control signal from ECU 200.

  The capacitor C2 is connected to the boost converter 60 in parallel. Capacitor C <b> 2 smoothes the DC voltage supplied from boost converter 60 and supplies it to inverter 20.

  When system voltage VH is supplied from boost converter 60, inverter 20 converts DC voltage into AC voltage based on control signal PWMI to operate motor generators MG1 and MG2. Thus, motor generators MG1 and MG2 are operated so as to generate torques specified by the respective torque command values. Inverter 20 includes a switching element and a diode, and operates in accordance with a control signal from ECU 200.

  Charging device 80 is an AC / DC converter that converts AC power from external power supply 400 into DC power. The input side of the charging device 80 is connected to the inlet 90. The output side of charging device 80 is connected to battery 70 via positive line PL2 and negative line NL2.

  Charging relay CHR includes a relay CHRB, a relay CHRP, and a relay CHRG. Opening / closing of each of relay CHRB, relay CHRP, and relay CHRG is controlled based on a signal from ECU 200.

  Relay CHRG is provided between first node 72 and negative electrode line NL2 connected to charging device 80. Between the second node 74 and the negative electrode line NL2, a relay CHRP is provided in parallel with the relay CHRG. Relay CHRB is provided between third node 76 and positive electrode line PL <b> 2 connected to charging device 80.

  With such a configuration, relay CHRB switches connection and non-connection of a path between positive line PL2 and positive electrode of battery 70. Relay CHRP switches connection and disconnection of a path between negative electrode line NL2 and negative electrode of battery 70 via precharge resistor R. Relay CHRG switches connection and non-connection of a path between negative electrode line NL2 and the negative electrode of battery 70 without passing through precharge resistor R.

  Capacitor C3 smoothes output voltage VCHG of charging device 80 and supplies it to battery 70. One end of capacitor C3 is connected to positive electrode line PL2. The other end of the capacitor C3 is connected to the negative electrode line NL2. That is, the capacitor C3 is connected to the battery 70 in parallel with the charging device 80.

  When a control signal for turning on the charging relay CHR is received from the ECU 200, the relay CHRB and the relay CHRG are finally turned on, so that the battery 70 and the charging device 80 Are electrically connected. At this time, before the relay CHRG is turned on after the relay CHRB is turned on, the relay CHRP is temporarily turned on to prevent the capacitor C3 from being turned on in order to prevent an excessive current from flowing. Charging is performed.

  As described above, the resistor R is a resistor for precharging the capacitor C3 and a resistor for precharging the capacitor C1. Thus, since the common resistor R can be used for the precharge of the capacitor C3 and the precharge of the capacitor C1, the number of components can be reduced.

  Inlet 90 is a power interface for receiving power from external power supply 400. Inlet 90 is configured to be connected to charging plug 402 connected to external power supply 400. The inlet 90 is arrange | positioned at the back side surface of the vehicle 1, the front of the vehicle 1, etc., for example.

  Charging plug 402 and external power supply 400 are connected by power lines 404 and 406. The power lines 404 and 406 are provided with an external power supply relay CCID. The external power supply relay CCID switches connection and disconnection of the path between the external power supply 400 and the charging plug 402. The external power supply relay CCID uses a signal line (not shown) that is different from the power lines 404 and 406 from the ECU 200 of the vehicle 1 to connect the route based on the control signal transmitted via the inlet 90 and the charging plug 402. Switch off connection.

  When charging plug 402 is connected to inlet 90 and charging relay CHR is turned on (that is, when relay CHRB and relay CHRG are turned on), charging device 80 is based on a control signal from ECU 200. External power (AC power) input to the inlet 90 is converted to power (DC power) that can charge the battery 70 and output to the battery 70. Thereby, the battery 70 is charged with external electric power. In the following description, charging the battery 70 using external power is referred to as “external charging”.

  Current sensor 202 detects current IB of battery 70. Current sensor 202 transmits detected current IB to ECU 200.

  Voltage sensor 204 detects a voltage VCHG between positive line PL2 and negative line NL2. Voltage sensor 204 transmits detected voltage VCHG to ECU 200.

  The ECU 200 includes a CPU (Central Processing Unit) and a memory, and executes predetermined arithmetic processing based on information stored in the memory and information from various sensors. ECU 200 controls each device of vehicle 1 based on the calculation result.

  For example, when the user performs an operation of connecting charging plug 402 to inlet 90, ECU 200 performs external charging of battery 70. ECU 200 stops external charging when, for example, the SOC (State Of Charge) of battery 70 reaches a fully charged state exceeding a threshold value during execution of external charging.

  When executing external charging of battery 70, ECU 200 turns on charging relay CHR and external power supply relay CCID and operates charging device 80. On the other hand, when stopping external charging of battery 70, ECU 200 stops the operation of charging device 80 and turns off charging relay CHR and external power supply relay CCID.

  In the vehicle 1 configured as described above, when the capacitor C3 is precharged to turn on the charging relay CHR, an abnormality such as a short circuit occurs in the circuit constituting the charging device 80, so that the resistor R is It may deteriorate early due to overcurrent. In this case, if the capacitor C1 is deteriorated until it cannot be precharged, the system main relay SMR cannot be turned on, electric power cannot be supplied to the boost converter 60, and the vehicle 1 cannot be driven. is there.

  Therefore, in the present embodiment, ECU 200 starts precharging of capacitor C3 that turns on relay CHRP before turning on relay CHRG, and then starts recharging of battery 70 until a predetermined time elapses. When the current IB continues to be equal to or greater than the threshold value α, the charging device 80 and the battery 70 are electrically disconnected to prohibit the operation of the charging relay CHR and to permit the operation of the system main relay SMR. .

  If it does in this way, since the charging device 80 and the battery 70 will be in the electrical disconnection state, deterioration of the resistor R can be suppressed. Further, the deterioration of the resistor R can be suppressed by prohibiting the operation of the charging relay CHR thereafter.

  FIG. 2 is a flowchart showing a control process executed by ECU 200 of vehicle 1 according to the present embodiment. This flowchart is repeatedly executed at a predetermined cycle. Each step of the flowchart is basically described as being realized by software processing by the ECU 200, but may be realized by hardware processing using an electronic circuit created in the ECU 200.

  In step (hereinafter step is referred to as S) 100, ECU 200 determines whether or not charging relay CHR is operating in order to precharge capacitor C3. ECU 200 determines that charging relay CHR is operating in order to precharge capacitor C3, for example, when relay SMRP is in the ON state.

  When it is determined that charging relay CHR is operating to precharge capacitor C3 (YES in S100), in S102, ECU 200 starts from the point when current IB becomes equal to or greater than threshold value α. It is determined whether or not the state of the threshold value α or more continues until a predetermined time elapses. If it is determined that the state in which current IB is equal to or greater than threshold value α continues until a predetermined time has elapsed (YES in S102), the process proceeds to S104.

  In S104, ECU 200 determines that current IB is in an abnormal state, and turns charging relay CHR off. That is, ECU 200 turns off both relay CHRB and relay CHRP.

  In S106, ECU 200 prohibits the operation of charging relay CHR after setting charging relay CHR to the OFF state. For example, ECU 200 turns on a prohibition flag indicating that the operation of charging relay CHR is prohibited. In this case, even when the charging plug 402 is connected to the inlet 90 thereafter, the ECU 200 does not turn on the charging relay CHR because the prohibition flag is on.

  ECU 200 permits operation of system main relay SMR. For example, ECU 200 turns on a permission flag indicating that the operation of system main relay SMR is permitted. ECU 200 then turns on system main relay SMR because the permission flag is on even when the user performs an operation to activate the system of vehicle 1. In this case, ECU 200 turns on each of relay SMRB and relay SMRP, and turns on relay SMRP while turning on relay SMRG after completion of precharging of capacitor C1.

  The operation of ECU 200 of vehicle 1 according to the present embodiment based on the above-described structure and flowchart will be described with reference to FIG.

  For example, it is assumed that the charging plug 402 is not connected to the inlet 90. At this time, as indicated by solid line LN1, solid line LN3, and solid line LN5 in FIG. 3, all of relay CHRP, relay CHRB, and relay CHRG are in the off state.

<When current IB is normal>
When charging plug 402 is connected to inlet 90 at time T (0), relay CHRB is turned on as shown by solid line LN3. Then, at time T (1), as shown by solid line LN1, relay CHRP is turned on to start precharging of capacitor C3 (YES in S100).

  When there is no abnormality such as a short circuit in the circuit of the charging device 80, the voltage VCHG starts increasing from time T (1) as time passes, as indicated by the solid line LN7 in FIG. On the other hand, as indicated by a solid line LN9 in FIG. 3, the current IB decreases as the precharge of the capacitor C3 proceeds after the current I (0) becomes larger than the threshold value α at time T (1). Go. Therefore, current IB decreases without continuing until a predetermined time elapses in a state equal to or greater than threshold value α (NO in S102).

  Therefore, at time T (3), when the change in current IB stops and voltage VCHG becomes V (0), it is determined that precharging of capacitor C3 is complete, and relay CHRG is turned on as shown by solid line LN5. Then, at time T (5), relay CHRP is turned off as indicated by solid line LN1.

<When current IB is abnormal>
When charging plug 402 is connected to inlet 90 at time T (0), relay CHRB is turned on as shown by solid line LN3. Then, at time T (1), as shown by solid line LN1, relay CHRP is turned on to start precharging of capacitor C3 (YES in S100).

  When there is an abnormality such as a short circuit in the circuit of the charging device 80, the voltage VCHG rapidly increases to the voltage V (0) at time T (1) as shown by the broken line LN8 when the relay CHRP is turned on. The voltage V (0) is maintained after time T (1). As a result, current IB rapidly rises to current IB (0) at time T (1), and then continues to be in a state equal to or greater than threshold value α.

  At time T (2), it is determined that the state in which current IB is equal to or greater than threshold value α continues until a predetermined time has elapsed (YES in S102), and charging relay CHR is turned off. (S104). That is, as indicated by a broken line LN4 in FIG. 3, relay CHRB is turned off. Thereafter, at time T (4), relay CHRP is turned off as indicated by broken line LN2 in FIG. Note that relay CHRG is maintained in the OFF state as indicated by broken line LN6 in FIG.

  Thereafter, the operation of charging relay CHR is prohibited, and the operation of system main relay SMR is permitted (S106). Therefore, when the system is subsequently started up by the user, the operation of system main relay SMR is started. That is, relay SMRP is turned on after relay SMRB is turned on, and precharging of capacitor C1 is started. After completion of precharging of capacitor C1, relay SMRG is turned on and then relay SMRP is turned off. By such an operation, the vehicle 1 is brought into a travelable state.

  As described above, according to the power supply device according to the present embodiment, the state in which current IB of battery 70 is equal to or higher than threshold value α until a predetermined time has elapsed after the start of precharging of capacitor C3. When continuing, the deterioration of the resistor R can be suppressed by electrically disconnecting the charging device 80 and the battery 70. Further, the deterioration of the resistor R can be suppressed by prohibiting the operation of the charging relay CHR thereafter. In addition, by permitting the operation of the system main relay SMR, the electric power of the battery 70 can be supplied to the electric load, so that the vehicle 1 can travel. Therefore, it is possible to provide a vehicle power supply device that suppresses deterioration of components that are commonly used during external charging and when supplying power to an electric load.

Hereinafter, modifications will be described.
In the above-described embodiment, the case where the present invention is applied to the hybrid vehicle 1 shown in FIG. 1 has been described as an example. However, the vehicle to which the present invention can be applied is not limited to the hybrid vehicle. You may apply to the electric vehicle which does not have.

  In the above-described embodiment, the case where the vehicle 1 is mounted with the battery 70 has been described as an example, but the battery 70 may use a power storage device other than the secondary battery. For example, a capacitor may be used instead of the secondary battery.

In addition, you may implement combining the above-mentioned modification, all or one part.
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.

  DESCRIPTION OF SYMBOLS 1 Hybrid vehicle, 20 Inverter, 30 Engine, 40 Power split device, 50 Driving wheel, 60 Boost converter, 70 Battery, 72 1st node, 74 2nd node, 76 3rd node, 80 Charging device, 90 inlet, 200 ECU 202 Current sensor, 204 Voltage sensor, 400 External power supply, 402 Charging plug, C1, C2, C3 capacitor, SMR system main relay, CHR charging relay.

Claims (1)

A power storage device for supplying power to the electrical load;
A resistor having one end connected to a first node connected to either the positive electrode or the negative electrode of the power storage device;
A first relay provided between the first power line connected to the electrical load, and a second node connected to the other end of the resistor and the first power line in parallel with the first relay. A load-side relay device including a second relay provided by
A charging device for charging the power storage device using an external power source;
A third relay provided between the first node and a second power line connected to the charging device; and a third relay provided in parallel with the third relay between the second node and the second power line. A charging-side relay device including four relays;
A capacitor having one end connected to the second power line and connected in parallel to the charging device with respect to the power storage device;
A control device for controlling the operation of the load side relay device and the charging side relay device,
The control device starts the precharge of the capacitor that turns on the fourth relay before turning on the third relay, and then the current of the power storage device continues until a predetermined time elapses. When the state of exceeding the threshold value continues, the charging device and the power storage device are electrically disconnected to prohibit the operation of the charging side relay device and the operation of the load side relay device is permitted. A power supply.

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