Power supply device and vehicle control device

Abstract

To simplify a constitution and to improve energy conversion efficiency.SOLUTION: A power supply device includes: a semiconductor relay disposed between an inverter portion for driving a motor and a battery, and switching a supply state in which electric power supplied from the battery is supplied to a power supply line of the inverter portion and a stop state in which power to the power supply line of the inverter portion is stopped; a relay driving portion for driving the semiconductor relay; and a driving voltage generation portion generating the driving voltage to drive the inverter driving portion for driving the inverter portion and the relay driving portion. A vehicle control device for controlling a vehicle includes the semiconductor relay, the relay driving portion, and the driving voltage generation portion.SELECTED DRAWING: Figure 1

Description

Technical Field

[0006] , , ,

[0005] , ,

[0001] The present invention relates to a power supply device and a vehicle control device.

Background Art

[0002] In recent years, a power supply device for supplying power to vehicles such as motorcycles has been known (see, for example, Patent Document 1). In such a power supply device, a protective fuse and a relay switch are arranged between the vehicle control device and the battery.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional power supply device as described above, in order to arrange a fuse and a relay switch between the vehicle control device and the battery, the layout of components and wiring in the vehicle becomes difficult, or there is a problem that the energy conversion efficiency decreases due to an increase in the wiring length caused by routing.

[0005] The present invention has been made to solve the above problems, and an object thereof is to provide a power supply device and a vehicle control device that can simplify the configuration and improve the energy conversion efficiency.

Means for Solving the Problems

[0006] To solve the above problems, one aspect of the present invention provides a vehicle control device that controls a vehicle, comprising: a semiconductor relay positioned between an inverter unit that drives an electric motor and a battery, which switches between a supply state in which power supplied from the battery is supplied to the power supply line of the inverter unit and a stop state in which the power supplied to the power supply line of the inverter unit is stopped; a relay drive unit that drives the semiconductor relay; and a drive voltage generation unit that generates a drive voltage to drive the inverter unit and the relay drive unit, wherein the vehicle control device comprises the semiconductor relay, the relay drive unit and the drive voltage generation unit. The vehicle control device, which controls the vehicle, comprises the semiconductor relay, the relay drive unit, and the drive voltage generation unit, and the vehicle control device comprises a reverse connection protection unit that switches the semiconductor relay to the stopped state when the battery is connected in the reverse direction, and the reverse connection protection unit comprises a Zener diode that detects that the battery is in the reverse connection state. This is a power supply device characterized by the following features.

[0009] Furthermore, in one aspect of the present invention, the vehicle control device is characterized in that, in the power supply device described above, the vehicle control device includes an overcurrent protection unit that switches the semiconductor relay to the stopped state when the current flowing through the power supply line of the inverter unit is equal to or greater than a threshold current.

[0010] Furthermore, in one aspect of the present invention, the power supply device described above is characterized in that the overcurrent protection unit comprises a current detection unit for detecting the current flowing through the power supply line of the inverter unit, and a switching unit for switching the semiconductor relay to the stopped state when the current detected by the current detection unit is equal to or greater than a threshold current.

[0011] Furthermore, in one aspect of the present invention, the vehicle control device in the above-described power supply device includes a control unit that performs switching control of the semiconductor relay and drive control of the inverter unit, and the control unit performs switching control of the semiconductor relay according to the state of the main switch that starts the vehicle.

[0012] Furthermore, one aspect of the present invention is a vehicle control device for controlling a vehicle, comprising: a semiconductor relay disposed between an inverter unit that drives an electric motor and a battery, which switches between a supply state in which power supplied from the battery is supplied to the power supply line of the inverter unit and a stop state in which the power supplied to the power supply line of the inverter unit is stopped; a relay drive unit that drives the semiconductor relay; an inverter drive unit that drives the inverter unit and a drive voltage generation unit that generates a drive voltage to drive the relay drive unit; and a control unit that performs switching control of the semiconductor relay and drive control of the inverter unit. The reverse connection protection unit switches the semiconductor relay to the stopped state when the battery is connected in the reverse direction. Equipped with The reverse connection protection unit includes a Zener diode for detecting that the battery is in the reverse connection state. This is a vehicle control device characterized by the following features. [Effects of the Invention]

[0013] According to the present invention, the power supply device includes a vehicle control device equipped with a semiconductor relay that switches between a power supply state and a stopped state for power supplied from the battery to the power supply line of the inverter unit, and the drive voltage generation unit is common in generating the drive voltage of the inverter unit and the drive voltage of the semiconductor relay. As a result, the power supply device does not require an external relay switch, and the external wiring can be shortened, thereby simplifying the configuration and improving energy conversion efficiency. [Brief explanation of the drawing]

[0014] [Figure 1] This is a block diagram showing an example of a power supply device according to this embodiment. [Figure 2] This is a block diagram showing an example of a semiconductor relay, relay drive unit, reverse connection protection unit, and overcurrent protection unit in this embodiment. [Figure 3] This flowchart shows an example of the operation of the power supply device according to this embodiment. [Figure 4] This figure shows the transition table for the reverse connection protection unit in this embodiment. [Figure 5] This flowchart shows an example of the operation of the overcurrent protection unit in this embodiment. [Figure 6]This is a timing chart showing an example of the operation of the overcurrent protection unit in this embodiment.

Mode for Carrying Out the Invention

[0015] Hereinafter, a power supply device and a vehicle control device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an example of the power supply device 1 according to this embodiment.

[0016] As shown in FIG. 1, the power supply device 1 includes an ECU 10, fuses (3, 6), and a main switch 4. The power supply device 1 supplies power to a vehicle such as a motorcycle, for example. The battery 2, the EFI load unit 5, the general load unit 7, and the ISG 8 are connected to the power supply device 1.

[0017] The battery 2 is, for example, a lead-acid battery, and its + (plus) electrode (positive electrode) is connected to the node N1, and its - (minus) electrode (negative electrode) is connected to the ground terminal. The battery 2 supplies power to the ISG 8 via the inverter unit 13 and supplies power to the EFI load unit 5, the general load unit 7, etc. via the main switch 4. Further, the battery 2 is charged by the power generated from the ISG 8 via the inverter unit 13.

[0018] The fuse 3 is connected between the + electrode (node N1) of the battery 2 and one end (node N2) of the main switch 4, and when an abnormal overcurrent flows mainly to the EFI load unit 5 and the ECU 10 via the main switch 4, it cuts off the connection between the battery 2 and the main switch 4.

[0019] The main switch 4 is, for example, a switch for starting the vehicle, and in the on state, it supplies the power of the battery 2 to the EFI load unit 5, the general load unit 7, etc.

[0020] The EFI (Electronic Fuel Injection) load unit 5 is a load unit mainly including an EFI which is an electronic control fuel injection device.

[0021] The fuse 6 is connected between one end (node N3) of the main switch 4 and the general load unit 7, and cuts off the connection between the general load unit 7 and the main switch 4 when an abnormal overcurrent flows through the general load unit 7.

[0022] The general load unit 7 is a load excluding the load related to the start of the engine by the EFI load unit 5 or the ISG 8, and is, for example, a load of a lighting system such as a headlamp and a tail lamp.

[0023] The ISG (Integrated Starter Generator) 8 is a generator with a motor function, and functions as both a starting device (starter) and a charging device (generator) of the engine. Note that the ISG 8 is an example of an electric motor.

[0024] The ECU (Electronic Control Unit) 10 is a vehicle control device that controls the vehicle. The ECU 10 includes a semiconductor relay 11, a relay drive unit 12, an inverter unit 13, a drive voltage generation unit 14, a control unit 15, an inverter drive unit 16, an EFI drive unit 17, a FET (Field Effect Transistor) 18, a reverse connection protection unit 20, and an overcurrent protection unit 30.

[0025] The semiconductor relay 11 is arranged between the inverter unit 13 and the battery 2, and switches between a supply state (on state) in which power supplied from the battery 2 is supplied to the power supply line L1 of the inverter unit 13 and a stop state (off state) in which power supply to the power supply line L1 of the inverter unit 13 is stopped. The semiconductor relay 11 is connected to the supply line (node N1) of the battery 2 via the reverse connection protection unit 20. Also, the semiconductor relay 11 is connected to the power supply line L1 of the inverter unit 13 via the overcurrent protection unit 30. Details of the configuration of the semiconductor relay 11 will be described later with reference to FIG. 2.

[0026] The relay drive unit 12 is a driver that drives the semiconductor relay 11 using the control voltage generated by the drive voltage generation unit 14. The relay drive unit 12 generates a drive signal that switches the state of the relay drive unit 12 based on the control signal S1 of the control unit 15, which will be described later.

[0027] The inverter unit 13 converts the DC power supplied from the battery 2 to the power supply line L1 via the semiconductor relay 11 into AC power to drive the ISG 8. Furthermore, when the ISG 8 is used as a generator, it functions as a synchronous rectifier circuit that converts the generated AC power into DC power for charging the battery 2.

[0028] The inverter section 13 includes FETs 131 to 136. Each of the FETs 131 to 136 is switched by a drive signal supplied from the inverter drive unit 16.

[0029] FET131 and FET132 are N-type channel MOS (Metal-Oxide-Semiconductor) FETs and are connected in series between the power supply line L1 and the ground line. The source terminal of FET131 and the drain terminal of FET132 are connected to node N4, and node N4 outputs the AC signal U, which is the drive signal for ISG8.

[0030] FET133 and FET134 are N-type channel MOSFETs connected in series between the power supply line L1 and the ground line. The source terminal of FET133 and the drain terminal of FET134 are connected to node N5, and node N5 outputs the AC signal V, which is the drive signal for ISG8.

[0031] FET135 and FET136 are N-type channel MOSFETs connected in series between the power supply line L1 and the ground line. The source terminal of FET135 and the drain terminal of FET136 are connected to node N6, and node N6 outputs the AC signal W, which is the drive signal for ISG8.

[0032] The drive voltage generation unit 14 generates a drive voltage to drive the inverter drive unit 16 and the relay drive unit 12. For example, when the main switch 4 is turned ON, the drive voltage generation unit 14 generates the drive voltage for the inverter drive unit 16 and the relay drive unit 12 based on the power supplied from node N3. The drive voltage generation unit 14 supplies the generated drive voltage to the relay drive unit 12 and the inverter drive unit 16.

[0033] The control unit 15 includes, for example, a CPU (Central Processing Unit) and controls the ECU 10. The control unit 15 performs, for example, switching control of the semiconductor relay 11 and drive control of the inverter unit 13.

[0034] The control unit 15 performs switching control of the semiconductor relay 11 according to the state of the main switch 4, for example. When the main switch 4 is in the ON state, the control unit 15 controls the semiconductor relay 11 to the ON state (supply state). When the main switch 4 is in the OFF state, the control unit 15 controls the semiconductor relay 11 to the OFF state (stopped state).

[0035] The control unit 15 changes the logic state of the control signal S1 that controls the semiconductor relay 11 according to the state of the main switch 4. The control unit 15 may also control the semiconductor relay 11 to the off state (stopped state) during periods other than when the engine is started and when the power generated by the ISG 8 is being used to charge the battery 2.

[0036] Furthermore, the control unit 15 outputs a control signal to the inverter drive unit 16 to drive the inverter unit 13 when starting the engine and when charging the battery 2 with the power generated by the ISG 8.

[0037] The inverter drive unit 16 generates a drive signal for the inverter unit 13 based on the control signal output by the control unit 15. The inverter drive unit 16 supplies the generated drive signal to the gate terminals of FETs 131 to FETs 136 of the inverter unit 13. The inverter drive unit 16 uses the drive voltage generated by the drive voltage generation unit 14 to generate control signals for FETs 131 to FETs 136 of the inverter unit 13 and switches FETs 131 to FETs 136.

[0038] Furthermore, the control unit 15 is constantly supplied with power converted from the battery 2 to the power supply voltage for the control circuit, and the drive voltage generation unit 14 is supplied with power from the battery 2 via the main switch 4.

[0039] The EFI drive unit 17 drives the EFI load unit 5. FET18 is an N-type channel MOSFET, positioned between the general load 7 and the ground line, and supplies power to the general load 7. FET18 is controlled by the control unit 15 and is controlled to the ON state when the EFI load 5 is used.

[0040] The reverse connection protection unit 20 is positioned between node N1 and semiconductor relay 11, and switches the semiconductor relay 11 to a stopped state when the battery 2 is connected in the reverse direction. The detailed configuration of the reverse connection protection unit 20 will be described later with reference to Figure 2.

[0041] The overcurrent protection unit 30 is positioned between the semiconductor relay 11 and the inverter unit 13. When the current flowing through the power supply line L1 of the inverter unit 13 exceeds a threshold current, the overcurrent protection unit 30 switches the semiconductor relay 11 to a stopped state. The detailed configuration of the overcurrent protection unit 30 will be described later with reference to Figure 2.

[0042] Next, with reference to Figure 2, the detailed configurations of the semiconductor relay 11, relay drive unit 12, reverse connection protection unit 20, and overcurrent protection unit 30 will be described. Figure 2 is a block diagram showing an example of the semiconductor relay 11, relay drive unit 12, reverse connection protection unit 20, and overcurrent protection unit 30 in this embodiment.

[0043] As shown in Figure 2, the semiconductor relay 11 comprises FETs 111 and FET 112, and resistors 113 to 116. FET111 is an N-type channel MOSFET, with its source terminal connected to node N7, its drain terminal to node N1, and its gate terminal to node N8.

[0044] FET112 is an N-type channel MOSFET, with its source terminal connected to node N7, its drain terminal connected to power supply line L1 via overcurrent protection unit 30, and its gate terminal connected to node N9. Note that FET111 and FET112 are connected in series so that their body diodes are facing in opposite directions.

[0045] Resistors 113 and 114 are connected in series between node N10 and node N7, and node N8, which is the connecting line between resistors 113 and 114, is connected to the gate terminal of FET 111. Specifically, resistor 113 is connected between node N10 and node N8, and resistor 114 is connected between node N8 and node N7.

[0046] Resistors 115 and 116 are connected in series between node N10 and node N7, and node N9, which is the connecting line between resistors 115 and 116, is connected to the gate terminal of FET 112. Specifically, resistor 115 is connected between node N10 and node N9, and resistor 116 is connected between node N9 and node N7.

[0047] The relay drive unit 12 is connected between the drive voltage generation unit 14 and node N10, and includes a resistor 121 and a transistor 122. Resistor 121 is connected between node N10 and the collector terminal of transistor 122, and limits the collector current of transistor 122.

[0048] Transistor 122 is a PNP bipolar transistor, with its emitter terminal connected to the supply line from the drive voltage generation unit 14, its base terminal connected to the signal line of the control signal S1 of the control unit 15, and its collector terminal connected to one end of resistor 121.

[0049] Transistor 122 turns ON when the control signal S1 is in an L state (Low state), and supplies the drive voltage from the drive voltage generation unit 14 to node N10, turning on FETs 111 and FET 112. Transistor 122 also turns OFF when the control signal S1 is in an open state (Hi-Z state), stops supplying the drive voltage to node N10, and turns off FETs 111 and FET 112.

[0050] The reverse connection protection unit 20 comprises a diode 21, a transistor 22, a resistor 23, and a Zener diode 24. Diode 21 has its anode terminal connected to the emitter terminal of transistor 22 and its cathode terminal connected to node N1. Diode 21 is connected so that current flows when battery 2 is connected in the reverse direction.

[0051] Transistor 22 is an NPN bipolar transistor, with its collector terminal connected to node N10, its base terminal connected to one end of resistor 23, and its emitter terminal connected to the anode terminal of diode 21. Transistor 22 is in the off state when battery 2 is properly connected. Transistor 22 is in the on state when battery 2 is connected in the reverse direction, turning off (stopping) the semiconductor relay 11 (FET 111 and FET 112).

[0052] Resistor 23 is connected between the base terminal of transistor 22 and the anode terminal of Zener diode 24, limiting the base current of transistor 22. The Zener diode 24 detects that the battery 2 is reverse-connected, with its anode terminal connected to resistor 23 and its cathode terminal connected to the ground. When the battery 2 is connected in the reverse direction, the Zener diode 24 turns on, turning on transistor 22.

[0053] The overcurrent protection unit 30 includes a current detection unit 31 and a switching unit 32. The current detection unit 31 detects the current flowing through the power supply line L1 of the inverter unit 13. The current detection unit 31 detects the current flowing through the power supply line L1 by converting the current flowing through the power supply line L1 into a voltage using a resistor 311. The current detection unit 31 comprises a resistor 311 and a differential amplifier 312.

[0054] Resistor 311 is a shunt resistor located on the power supply line L1, which converts the current flowing through the power supply line L1 into a voltage due to the potential difference across its terminals. The terminals of resistor 311 are connected to the differential amplifier 312. Resistor 311 converts the current flowing through the power supply line L1 into a voltage.

[0055] The differential amplifier 312 is, for example, an operational amplifier, with its non-inverting input terminal (+ terminal) connected to one end of the resistor 311 on the semiconductor relay 11 side, and its inverting input terminal (- terminal) connected to one end of the resistor 311 on the inverter section 13 side (power supply line L1). The differential amplifier 312 detects the current flowing through the power supply line L1 as a voltage difference (potential difference across the resistor 311) and outputs it to the switching unit 32.

[0056] The switching unit 32 switches the semiconductor relay 11 to the stopped state when the current detected by the current detection unit 31 is equal to or greater than the threshold current. The switching unit 32 includes an overcurrent determination unit 321, a resistor 322, a transistor 323, and a diode 324.

[0057] The overcurrent detection unit 321 determines whether the current detected by the current detection unit 31 is greater than or equal to the threshold current based on whether the output voltage of the differential amplifier 312 is greater than or equal to the threshold voltage Vth. If the output voltage of the differential amplifier 312 is greater than or equal to the threshold voltage Vth, the overcurrent detection unit 321 outputs an H state to the base terminal of the transistor 323 via the resistor 322. If the output voltage of the differential amplifier 312 is less than the threshold voltage Vth, the overcurrent detection unit 321 outputs an L state to the base terminal of the transistor 323 via the resistor 322.

[0058] The resistor 322 is placed between the output line of the overcurrent detection unit 321 and the base terminal of the transistor 323, and limits the base current of the transistor 323.

[0059] Transistor 323 is an NPN bipolar transistor, with its collector terminal connected to the cathode terminal of diode 324, its base terminal connected to one end of resistor 322, and its emitter terminal connected to the ground line. Transistor 323 turns off when the overcurrent detection unit 321 outputs an L state. Also, when the overcurrent detection unit 321 outputs an L state, transistor 323 turns off, setting node N10 to an L state and turning off (stopping) the semiconductor relay.

[0060] Diode 324 has its anode terminal connected to node N10 and its cathode terminal connected to the collector terminal of transistor 323, preventing reverse current flow to node N10.

[0061] Next, the operation of the power supply device 1 according to this embodiment will be described with reference to the drawings. Figure 3 is a flowchart showing an example of the operation of the power supply device 1 according to this embodiment. Here, the control process of the semiconductor relay 11 by the power supply device 1 will be described.

[0062] As shown in Figure 3, the control unit 15 of the power supply device 1 first determines whether the main switch 4 is in the ON state or not (step S101). If the main switch 4 is in the ON state (step S101: YES), the control unit 15 proceeds to step S102. If the main switch 4 is not in the ON state (is in the OFF state) (step S101: NO), the control unit 15 proceeds to step S104.

[0063] In step S102, the control unit 15 turns on the semiconductor relay 11. The control unit 15 turns on the transistor 122 by setting the control signal S1 to the low state. As a result, node N10 becomes high, and the semiconductor relay 11 (FET 111 and FET 112) becomes on (supply state).

[0064] Next, the control unit 15 determines whether or not it has detected an abnormality (step S103). The control unit 15 determines whether or not any abnormality has occurred in the ECU 10 by detecting various sensors (not shown), for example. If the control unit 15 detects an abnormality (step S103: YES), it proceeds to step S104. If the control unit 15 does not detect an abnormality (step S103: NO), it returns to step S101.

[0065] In step S104, the control unit 15 turns off the semiconductor relay 11. The control unit 15 turns off the transistor 122 by setting the control signal S1 to the high state. As a result, nodes N8 and N9 are at the same potential as node N7, and the semiconductor relay 11 (FET 111 and FET 112) is turned off (stopped). After processing in step S104, the control unit 15 returns to processing in step S101.

[0066] Next, with reference to Figure 4, the operation of the reverse connection protection unit 20 according to this embodiment will be described. Figure 4 is a diagram showing the transition table of the reverse connection protection unit 20 in this embodiment.

[0067] The transition table shown in Figure 4 illustrates the states of "battery connection," "node N1," "GND terminal," "transistor 22," and "semiconductor relay," from left to right.

[0068] In Figure 4, when the "battery connection" is in a "normal connection" state, "node N1" becomes positive voltage and the "GND terminal" (ground terminal) becomes "0V". In this case, the Zener diode 24 causes the base terminal of transistor 22 to become L, and "transistor 22" becomes "off". As a result, node N10 maintains a state where a drive voltage is supplied, and the "semiconductor relay" (semiconductor relay 11) becomes "on".

[0069] Furthermore, if the "battery connection" is "reverse connected" (reverse polarity), "node N1" will have a negative voltage and the "GND terminal" (ground terminal) will be "0V". In this case, the Zener diode 24 will be in the ON state, the base terminal of transistor 22 will be in the H state, and "transistor 22" will be in the "OFF state". As a result, the supply of drive voltage to node N10 will be stopped, and nodes N8 and N9 will be at the same potential as node N7, so the "semiconductor relay" (semiconductor relay 11) will be in the "OFF state".

[0070] Thus, when the battery 2 is connected in reverse, the reverse connection protection unit 20 performs control to switch the semiconductor relay 11 to the off state (stopped state).

[0071] Next, the operation of the overcurrent protection unit 30 according to this embodiment will be described with reference to Figures 5 and 6. Figure 5 is a flowchart showing an example of the operation of the overcurrent protection unit 30 in this embodiment.

[0072] As shown in Figure 5, the overcurrent protection unit 30 first determines whether the detected current is greater than or equal to the threshold current (step S201). The current detection unit 31 of the overcurrent protection unit 30 converts the current flowing through the power supply line L1 into a voltage, and the overcurrent determination unit 321 of the switching unit 32 of the overcurrent protection unit 30 determines whether the output voltage of the differential amplifier 312 of the current detection unit 31 is greater than or equal to the threshold voltage Vth. The threshold voltage Vth is a voltage value corresponding to the threshold current used to determine overcurrent. If the output voltage of the differential amplifier 312 is greater than or equal to the threshold voltage Vth (detected current is greater than or equal to the threshold current) (step S201: YES), the overcurrent determination unit 321 proceeds to step S202. If the output voltage of the differential amplifier 312 is less than the threshold voltage Vth (detected current is less than the threshold current) (step S201: NO), the overcurrent determination unit 321 proceeds to step S203.

[0073] In step S202, the switching unit 32 of the overcurrent protection unit 30 turns off the semiconductor relay 11. As the transistor 323 of the switching unit 32 turns on, node N10 becomes at the potential of the ground line, and the semiconductor relay 11 (FET 111 and FET 112) turns off (stops). After the processing in step S202, the process returns to step S201.

[0074] Furthermore, in step S203, the switching unit 32 of the overcurrent protection unit 30 turns on the semiconductor relay 11. As the transistor 323 of the switching unit 32 turns off, the ground line at node N10 becomes high (voltage equivalent to the drive voltage), and the semiconductor relay 11 (FET 111 and FET 112) turns on (supply state). After the processing in step S203, the process returns to step S201.

[0075] Figure 6 is a timing chart showing an example of the operation of the overcurrent protection unit 30 in this embodiment. In Figure 6, waveforms W1 to W4, respectively, represent the potential difference across resistor 311 (output voltage of differential amplifier 312), the logic state of the output of overcurrent detection unit 321, the logic state of control signal S1, and the logic state of node N10. State ST1 indicates the state of semiconductor relay 11. The horizontal axis for each waveform and state ST1 represents time.

[0076] In Figure 6, when the potential difference across resistor 311 in waveform W1 is less than the threshold voltage Vth, the overcurrent protection unit 30 outputs an L state (see waveform W2), and transistor 323 turns off. Also, the control unit 15 sets the control signal S1 to an L state (see waveform W3), and transistor 122 turns on. As a result, a drive voltage is supplied to node N10 from the drive voltage generation unit 14, and node N10 turns H (see waveform W4). This turns on the semiconductor relay 11 (see state ST1).

[0077] Next, at time T1, when waveform W1 exceeds the threshold voltage Vth, the overcurrent protection unit 30 outputs an H state (see waveform W2), and transistor 323 turns ON. As a result, node N10 is connected to the ground line and enters an L state (see waveform W4), and semiconductor relay 11 turns OFF (see state ST1).

[0078] Next, the control unit 15 detects an abnormality and, at time T2, sets the control signal S1 to an open state (Hi-Z state) (see waveform W3). This turns off the transistor 122. Note that when the control signal S1 is set to an open state (Hi-Z state), it appears as a high state. Next, at time T3, when waveform W1 falls below the threshold voltage Vth, the overcurrent protection unit 30 outputs an L state (see waveform W2), but because the control signal S1 is in the H state, the semiconductor relay 11 remains in the OFF state (see state ST1).

[0079] As described above, the power supply device 1 according to this embodiment comprises a semiconductor relay 11, a relay drive unit 12, and a drive voltage generation unit 14. The semiconductor relay 11 is positioned between the inverter unit 13 that drives the ISG 8 (motor) and the battery 2, and switches between a supply state in which power supplied from the battery 2 is supplied to the power supply line L1 of the inverter unit 13, and a stop state in which power is stopped from being supplied to the power supply line L1 of the inverter unit 13. The relay drive unit 12 drives the semiconductor relay 11. The drive voltage generation unit 14 generates a drive voltage to drive the inverter drive unit 16 that drives the inverter unit 13 and the relay drive unit 12. The ECU 10 (vehicle control unit) that controls the vehicle comprises the semiconductor relay 11, the relay drive unit 12, and the drive voltage generation unit 14.

[0080] As a result, the power supply device 1 according to this embodiment includes a semiconductor relay 11 in the ECU 10 that switches between a power supply state and a stopped state for power supplied from the battery 2 to the power supply line L1 of the inverter unit 13, and the drive voltage generation unit 14 is made common for generating the drive voltage of the inverter unit 13 and the drive voltage of the semiconductor relay 11. As a result, the power supply device 1 according to this embodiment does not require an external relay switch, for example, and the external wiring can be shortened, thus simplifying the configuration and improving energy conversion efficiency. In other words, the power supply device 1 according to this embodiment can improve efficiency, weight, and layoutability by eliminating the inclusion of external wiring and external elements (for example, relay components, etc.), and can save space inside the ECU 10 by using a common drive voltage (boost power supply).

[0081] Furthermore, in this embodiment, the power supply device 1 includes a reverse connection protection unit 20 that switches the semiconductor relay 11 to a stopped state when the battery 2 is connected in the reverse direction. The ECU 10 also includes a reverse connection protection unit 20.

[0082] As a result, the power supply device 1 according to this embodiment can appropriately detect the reverse connection state of the battery 2, and can achieve reliability equivalent to or better than that of cases using external wiring and external elements by providing a reverse connection protection function.

[0083] Furthermore, in this embodiment, the reverse connection protection unit 20 includes a Zener diode 24 that detects when the battery 2 is in a reverse connection state. As a result, the power supply device 1 according to this embodiment can appropriately determine if the battery 2 is reverse-connected with a simple configuration by using a Zener diode 24.

[0084] Furthermore, in this embodiment, the power supply device 1 includes an overcurrent protection unit 30 that switches the semiconductor relay 11 to a stopped state when the current flowing through the power supply line L1 of the inverter unit 13 is equal to or greater than a threshold current. The ECU 10 also includes an overcurrent protection unit 30.

[0085] As a result, the power supply device 1 according to this embodiment can appropriately detect when an overcurrent flows through the inverter unit 13, and can achieve reliability equivalent to or better than that of a device using external wiring and external components by providing an overcurrent protection function.

[0086] Furthermore, in this embodiment, the overcurrent protection unit 30 includes a current detection unit 31 that detects the current flowing through the power supply line L1 of the inverter unit 13, and a switching unit 32 that switches the semiconductor relay 11 to a stopped state when the current detected by the current detection unit 31 is equal to or greater than a threshold current.

[0087] As a result, the power supply device 1 according to this embodiment can appropriately detect when an overcurrent flows through the inverter unit 13 with a simple configuration, and can also add a protection function against overcurrent.

[0088] In this embodiment, the power supply device 1 includes a control unit 15 that controls the switching of the semiconductor relay 11 and the drive of the inverter unit 13. The control unit 15 performs the switching control of the semiconductor relay 11 according to the state of the main switch 4 that starts the vehicle. The ECU 10 also includes a control unit 15. As a result, the power supply device 1 according to this embodiment can appropriately perform switching control of the semiconductor relay 11 with a simple configuration.

[0089] Furthermore, in this embodiment, the semiconductor relay 11 includes two MOS transistors connected in series with their body diodes facing in reverse. As a result, the power supply device 1 according to this embodiment can interrupt the connection between the battery 2 and the inverter unit 13 in the same way as a relay component, with a simple configuration.

[0090] Furthermore, the ECU 10 (vehicle control device) according to this embodiment is an ECU 10 that controls the vehicle and comprises a semiconductor relay 11, a relay drive unit 12, a drive voltage generation unit 14, and a control unit 15. The semiconductor relay 11 is positioned between the inverter unit 13 that drives the ISG 8 (motor) and the battery 2, and switches between a supply state in which power supplied from the battery 2 is supplied to the power supply line L1 of the inverter unit 13, and a stop state in which power is stopped from the power supply line L1 of the inverter unit 13. The relay drive unit 12 drives the semiconductor relay 11. The drive voltage generation unit 14 generates a drive voltage to drive the inverter drive unit 16 that drives the inverter unit 13 and the relay drive unit 12. The control unit 15 controls the switching of the semiconductor relay 11 and the driving of the inverter unit 13.

[0091] As a result, the ECU 10 (vehicle control device) according to this embodiment achieves the same effects as the power supply device 1 described above, simplifies the configuration, and improves energy conversion efficiency.

[0092] It should be noted that the present invention is not limited to the embodiments described above, and can be modified without departing from the spirit of the invention. For example, in the above embodiment, an example was described in which an N-type channel MOSFET is used for the semiconductor relay 11, but it is not limited to this, and other FETs such as P-type channel MOSFETs or other semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors) may be used.

[0093] Furthermore, although the above embodiment describes an example of using an ISG as an example of an electric motor, it is not limited to this, and other electric motors, such as motors that do not have a generator function, may be used. In this case, the control unit 15 may control the semiconductor relay 11 to the off state (stopped state) after the engine starts.

[0094] Furthermore, in the above embodiment, the configurations of the semiconductor relay 11, relay drive unit 12, reverse connection protection unit 20, and overcurrent protection unit 30 are not limited to the configuration shown in Figure 2, but may be other methods and other configurations.

[0095] The ECU 10 described above has a computer system inside. The processing steps, such as the switching control of the semiconductor relay 11 and the drive control of the inverter unit 13, are stored in program form on a computer-readable recording medium, and the above processing is performed when the computer reads and executes this program. Here, a computer-readable recording medium refers to a magnetic disk, magneto-optical disk, CD-ROM, DVD-ROM, semiconductor memory, etc. Alternatively, this computer program may be distributed to a computer via a communication line, and the computer that receives the distribution may execute the program. [Explanation of Symbols]

[0096] 1 Power supply device 2 batteries 3, 6 fuses 4 Main Switch 5 EFI Load Section 7 General load section 8 ISG 10 ECU 11 Semiconductor relays 12 Relay drive unit 13 Inverter section 14 Drive voltage generation unit 15 Control Unit 16 Inverter drive unit 17 EFI drive unit 18, 111, 112, 131~136 FETs 20 Reverse connection protection section 21,324 diodes 22, 122, 323 transistors 23, 113-116, 121, 311, 322 resistors 24 Zener diodes 30 Overcurrent protection section 31 Current detection unit 32 Switching section 312 Differential Amplifier 321 Overcurrent judgment section

Claims

1. A semiconductor relay is positioned between the inverter unit that drives the electric motor and the battery, and switches between a supply state in which power is supplied from the battery to the power supply line of the inverter unit, and a stop state in which the power to the power supply line of the inverter unit is stopped. A relay drive unit that drives the semiconductor relay, An inverter drive unit that drives the inverter unit and a drive voltage generation unit that generates a drive voltage to drive the relay drive unit. Equipped with, A vehicle control device that controls the vehicle comprises the semiconductor relay, the relay drive unit, and the drive voltage generation unit. The aforementioned vehicle control device is The battery is connected in the reverse direction, and the reverse connection protection unit switches the semiconductor relay to the stopped state. The reverse connection protection unit includes a Zener diode for detecting that the battery is in the reverse connection state. A power supply device characterized by the following features.

2. The aforementioned vehicle control device is The inverter unit includes an overcurrent protection unit that switches the semiconductor relay to the stopped state when the current flowing through the power supply line exceeds a threshold current. The power supply device according to feature 1.

3. The overcurrent protection unit is, A current detection unit for detecting the current flowing through the power supply line of the inverter unit, A switching unit that switches the semiconductor relay to the stopped state when the current detected by the current detection unit is equal to or greater than the threshold current, The power supply device according to claim 2, characterized by comprising:

4. The aforementioned vehicle control device is The system includes a control unit that controls the switching of the semiconductor relay and the drive of the inverter section, The control unit performs switching control of the semiconductor relay according to the state of the main switch that starts the vehicle. A power supply device according to any one of claims 1 to 3, characterized by the features described above.

5. A vehicle control device that controls a vehicle, A semiconductor relay is positioned between the inverter unit that drives the electric motor and the battery, and switches between a supply state in which power is supplied from the battery to the power supply line of the inverter unit, and a stop state in which the power to the power supply line of the inverter unit is stopped. A relay drive unit that drives the semiconductor relay, An inverter drive unit that drives the inverter unit and a drive voltage generation unit that generates a drive voltage to drive the relay drive unit, A control unit that controls the switching of the semiconductor relay and the drive of the inverter unit, The reverse connection protection unit switches the semiconductor relay to the stopped state when the battery is connected in the reverse direction. Equipped with The reverse connection protection unit includes a Zener diode for detecting that the battery is in the reverse connection state. A vehicle control device characterized by the following features.

Images