WO2017043297A1 - Control device - Google Patents

Control device Download PDF

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Publication number
WO2017043297A1
WO2017043297A1 PCT/JP2016/074382 JP2016074382W WO2017043297A1 WO 2017043297 A1 WO2017043297 A1 WO 2017043297A1 JP 2016074382 W JP2016074382 W JP 2016074382W WO 2017043297 A1 WO2017043297 A1 WO 2017043297A1
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WO
WIPO (PCT)
Prior art keywords
switch
current
semiconductor
circuit
temperature
Prior art date
Application number
PCT/JP2016/074382
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French (fr)
Japanese (ja)
Inventor
佳祐 眞瀬
Original Assignee
株式会社オートネットワーク技術研究所
住友電装株式会社
住友電気工業株式会社
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Application filed by 株式会社オートネットワーク技術研究所, 住友電装株式会社, 住友電気工業株式会社 filed Critical 株式会社オートネットワーク技術研究所
Publication of WO2017043297A1 publication Critical patent/WO2017043297A1/en

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/08—Modifications for protecting switching circuit against overcurrent or overvoltage
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/16—Modifications for eliminating interference voltages or currents
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/687—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being field-effect transistors

Definitions

  • the present invention relates to a control device for turning on and off a semiconductor switch.
  • a power supply system in which the positive electrodes of two batteries are connected by a switch is widespread.
  • a semiconductor transistor that is smaller and lighter than a mechanical switch that is mechanically turned on and off as a switch that connects the positive electrodes of the two batteries.
  • FET Field Effective Transistor
  • Such a semiconductor switch has a first end, a second end, and a third end, and is connected between the second end and the third end connected to the positive electrodes of the two batteries according to the voltage value of the first end. Is adjusted.
  • the semiconductor switch is an FET
  • the first end is a gate
  • the second end is one of a drain and a source
  • the third end is the other of the drain and the source.
  • Patent Document 1 discloses a control device for turning on and off a semiconductor switch, specifically, an N-channel FET.
  • the control device turns on the semiconductor switch by adjusting the voltage value at the first end of the semiconductor switch to a certain voltage value or more, and adjusts the voltage value at the first end of the semiconductor switch to be less than the certain voltage value. To turn off the semiconductor switch.
  • the resistance value between the second end and the third end increases and flows between the second end and the third end.
  • the current value decreases.
  • switching loss occurs in the semiconductor switch. The switching loss is calculated by integrating the product of the resistance value and the current value over a period during which the semiconductor switch is turned off.
  • the semiconductor switch when the semiconductor switch is turned from on to off, the value of the current flowing between the second end and the third end changes, so that an electromagnetic wave is generated from the semiconductor switch.
  • the speed at which the semiconductor switch is turned from on to off is higher, the value of the current flowing between the second end and the third end changes more rapidly, so that an electromagnetic wave having a high frequency component is generated.
  • the peripheral device of the semiconductor switch may malfunction due to interference of the electromagnetic wave with the control signal. In order to reduce the probability that a peripheral device malfunctions, it is necessary to suppress the frequency with which electromagnetic waves having high-frequency components are generated.
  • the present invention has been made in view of such circumstances, and its object is to suppress the frequency of generation of electromagnetic waves having high-frequency components while maintaining the temperature of the semiconductor switch within a predetermined range. It is to provide a possible control device.
  • the control device has a first end, a second end, and a third end, and the resistance value between the second end and the third end decreases as the voltage value of the first end increases.
  • a first switch having a predetermined voltage applied to one end and the first end of the semiconductor switch connected to the other end, and the other end of the first switch
  • a first circuit having one end connected to the first circuit, a first circuit-side switch having one end connected to the other end of the first circuit, an end connected to the other end of the first switch, and an absolute value of impedance
  • the second circuit has a second circuit smaller than the absolute value of the impedance of the first circuit, and a second circuit side switch having one end connected to the other end of the second circuit.
  • a predetermined voltage is applied to one end of the first switch, and one end of each of the first circuit and the second circuit is connected to the other end of the first switch.
  • One ends of the first circuit side switch and the second circuit side switch are connected to the other ends of the first circuit and the second circuit, respectively.
  • the other ends of the first circuit side switch and the second circuit side switch are grounded, for example.
  • the other end of the first switch is connected to the first end of the semiconductor switch.
  • the absolute value of the impedance of the second circuit is smaller than the absolute value of the impedance of the first circuit.
  • the first switch, the first circuit side switch, and the second circuit side switch are turned on, off, and off, from one end of the first switch to which a predetermined voltage is applied.
  • a current flows through a parasitic capacitor having one end connected to the first end of the semiconductor switch, and charges are accumulated in the parasitic capacitor.
  • the voltage across the parasitic capacitance rises and the voltage value at the first end rises.
  • the resistance value between the second end and the third end of the semiconductor switch decreases, and the semiconductor switch is turned on.
  • the first switch When the first switch is turned off and one of the first circuit side switch and the second circuit side switch is turned on, a current flows from the parasitic capacitance through the first circuit or the second circuit, and both ends of the parasitic capacitance.
  • the voltage value at the first end decreases with the voltage value between.
  • the resistance value between the second end and the third end of the semiconductor switch increases, and the semiconductor switch is turned off.
  • the absolute value of the impedance of the second circuit is smaller than the absolute value of the impedance of the first circuit.
  • the time for the semiconductor switch to turn off is long, and when the second circuit side switch is turned on, the time for the semiconductor switch to turn from on to off is short.
  • the electromagnetic wave generated from the semiconductor switch does not include a high frequency component
  • the second circuit side switch is turned on, the switching loss is small.
  • the control device includes a current information acquisition unit that acquires current information indicating a current value flowing between the second end and the third end, and a current value indicated by the current information acquired by the current information acquisition unit is a current value.
  • a current value indicated by the current information acquired by the current information acquisition unit is a current value.
  • the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off, and the current value indicated by the current information acquired by the current information acquisition unit is equal to or greater than the current threshold value.
  • a switch control unit that turns off, off, and on each of the first switch, the first circuit side switch, and the second circuit side switch is provided.
  • current information indicating a current value flowing between the second end and the third end of the semiconductor switch is acquired.
  • the current value indicated by the acquired current information is less than the current threshold, a large switching loss is unlikely to occur, so the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off.
  • the semiconductor switch is turned on from off over a long time, high frequency components are not included in the electromagnetic wave generated from the semiconductor switch.
  • the switching loss is also small and the temperature of the semiconductor switch is maintained within a predetermined range.
  • the current value indicated by the acquired current information is equal to or greater than the current threshold value
  • the current value flowing between the second end and the third end of the semiconductor switch is large, so the first switch, the first circuit side switch, and the second circuit Turn the side switch off, off and on.
  • the semiconductor switch is quickly turned from on to off, the switching loss is small and the temperature of the semiconductor switch is maintained within a predetermined range.
  • the switching loss is always small, and the current value flowing through the second end and the third end of the semiconductor switch
  • the semiconductor switch is turned off from on in a short time, so that an electromagnetic wave having a high frequency component is generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
  • the control device includes a temperature information acquisition unit that acquires temperature information indicating a temperature of the semiconductor switch, and the temperature indicated by the temperature information acquired by the temperature information acquisition unit is less than a temperature threshold.
  • a temperature information acquisition unit that acquires temperature information indicating a temperature of the semiconductor switch, and the temperature indicated by the temperature information acquired by the temperature information acquisition unit is less than a temperature threshold.
  • 1 switch, the first circuit side switch and the second circuit side switch are turned off, on and off, respectively, and when the temperature indicated by the temperature information acquired by the temperature information acquisition unit is equal to or higher than a temperature threshold, the first switch, And a switch controller that turns off, off, and on each of the first circuit side switch and the second circuit side switch.
  • the energy consumed as heat by the on-resistance of the semiconductor switch increases, and the temperature of the semiconductor switch To rise.
  • the temperature indicated by the acquired temperature information is less than the temperature threshold, a large switching loss is unlikely to occur, so the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off.
  • the semiconductor switch is turned on from off over a long time, high frequency components are not included in the electromagnetic wave generated from the semiconductor switch.
  • the switching loss is also small and the temperature of the semiconductor switch is maintained within a predetermined range.
  • the temperature indicated by the acquired temperature information is equal to or higher than the temperature threshold value
  • the current value flowing between the second end and the third end of the semiconductor switch is large, so the first switch, the first circuit side switch, and the second circuit side Turn the switch off, off and on.
  • the semiconductor switch is quickly turned from on to off, the switching loss is small and the temperature of the semiconductor switch is maintained within a predetermined range.
  • the switching loss is always small, and the current value flowing through the second end and the third end of the semiconductor switch
  • the semiconductor switch is turned off from on in a short time, so that an electromagnetic wave having a high frequency component is generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
  • the present invention it is possible to suppress the frequency with which electromagnetic waves having high frequency components are generated while maintaining the temperature of the semiconductor switch within a predetermined range.
  • FIG. 1 is a circuit diagram of a power supply system in Embodiment 1.
  • FIG. It is a circuit diagram of a control device. It is a circuit diagram of a circuit for low speed. It is a circuit diagram of the circuit for high speed. It is explanatory drawing of operation
  • 6 is a circuit diagram of a power supply system according to Embodiment 2.
  • FIG. It is a circuit diagram of a control device.
  • FIG. 1 is a circuit diagram of a power supply system 1 according to the first embodiment.
  • the power supply system 1 is suitably mounted on a vehicle and includes a first battery 10, a second battery 11, loads 12, 13, semiconductor switches 14, 15, a current sensor 16, a temperature sensor 17, a control device 18, and a resistor R1.
  • Each of the semiconductor switches 14 and 15 is an N-channel FET and has a gate, a drain, and a source.
  • a parasitic capacitance P14 is formed between the gate and source of the semiconductor switch 14, and a parasitic capacitance P15 is also formed between the gate and source of the semiconductor switch 15.
  • One end of the load 12 and the drain of the semiconductor switch 14 are connected to the positive electrode of the first battery 10.
  • the source of the semiconductor switch 14 is connected to the source of the semiconductor switch 15.
  • the drain of the semiconductor switch 15 is connected to the positive electrode of the second battery 11 and one end of the load 13.
  • the negative electrodes of the first battery 10 and the second battery 11 and the other ends of the loads 12 and 13 are grounded.
  • One end of a resistor R 1 is further connected to the source of the semiconductor switch 14.
  • the other end of the resistor R1 is grounded.
  • the gates of the semiconductor switches 14 and 15, the current sensor 16, and the temperature sensor 17 are individually connected to the control device 18.
  • the resistance value between the drain and the source decreases as the gate voltage value increases with the source potential as a reference.
  • Each of the semiconductor switches 14 and 15 is turned on and off by the control device 18.
  • the gate corresponds to the first end
  • one of the drain and the source corresponds to the second end
  • the other corresponds to the third end.
  • the control device 18 When the semiconductor switch 14 is turned on, the control device 18 outputs a constant voltage toward the gate of the semiconductor switch 14. As a result, current flows in the order of the parasitic capacitance P14 and the resistor R1, and charges are accumulated in the parasitic capacitance P14. Due to the charge accumulation, the voltage value between both ends of the parasitic capacitance P14, that is, the gate voltage value based on the source potential increases, and the resistance value between the drain and source of the semiconductor switch 14 decreases. As a result, the semiconductor switch 14 is turned on, and a current can flow between the source and drain of the semiconductor switch 14.
  • the control device 18 causes the parasitic capacitance P14 to discharge when the semiconductor switch 14 is turned off. As a result, the charge accumulated in the parasitic capacitance P14 is released. Due to the discharge of the charge, the voltage value across the parasitic capacitance P14 decreases, and the resistance value between the drain and source of the semiconductor switch 14 increases. As a result, the semiconductor switch 14 is turned off, and the current flowing between the source and drain of the semiconductor switch 14 is interrupted.
  • the control device 18 turns on or off the semiconductor switch 15 similarly to the semiconductor switch 14.
  • the control device 18 turns the semiconductor switch 15 on or off by replacing the semiconductor switch 14 and the parasitic capacitance P14 with the semiconductor switch 15 and the parasitic capacitance P15, respectively.
  • the structure to perform can be described.
  • the control device 18 turns on the semiconductor switches 14 and 15 substantially simultaneously and turns off the semiconductor switches 14 and 15 substantially simultaneously. Since the source of the semiconductor switch 14 is connected to the source of the semiconductor switch 15, when the semiconductor switches 14 and 15 are off, a current flows through parasitic diodes (not shown) of the semiconductor switches 14 and 15, respectively. There is no.
  • the first battery 10 is, for example, a lithium ion battery.
  • the output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11.
  • the first battery 10 stores electric power generated by a generator (not shown) that generates power in conjunction with the vehicle engine.
  • the first battery 10 supplies power to the second battery 11 and the loads 12 and 13 when the semiconductor switches 14 and 15 are on. When the semiconductor switches 14 and 15 are off, the first battery 10 supplies power to the load 12 and does not supply power to the second battery 11 and the load 13.
  • the second battery 11 is, for example, a lead storage battery. As described above, when the semiconductor switches 14 and 15 are on, power is supplied from the first battery 10 to the second battery 11 and the second battery 11 stores electricity. When the semiconductor switches 14 and 15 are off, the second battery 11 supplies power to the load 13.
  • Each of the loads 12 and 13 is an electric device mounted on the vehicle.
  • the load 12 operates using the electric power supplied from the first battery 10.
  • the load 13 operates using the power supplied from the first battery 10 when the semiconductor switches 14 and 15 are on, and the power supplied from the second battery 11 when the semiconductor switches 14 and 15 are off. Operates with.
  • the current sensor 16 detects the value of current flowing between the drain and source of the semiconductor switch 14.
  • the current sensor 16 outputs current information indicating the detected current value, that is, the current value flowing between the drain and source of the semiconductor switch 14 to the control device 18.
  • the control device 18 acquires current information from the current sensor 16.
  • the resistance value of the resistor R1 is sufficiently larger than the combined resistance value of the on-resistances of the semiconductor switches 14 and 15. For this reason, when the semiconductor switches 14 and 15 are on, the value of the current flowing between the drain and the source of the semiconductor switch 14 substantially matches the value of the current flowing between the drain and the source of the semiconductor switch 15.
  • the temperature sensor 17 is constituted by a thermistor, for example, and detects the temperature of the semiconductor switch 14.
  • the temperature sensor 17 outputs temperature information indicating the detected temperature, that is, the temperature of the semiconductor switch 14 to the control device 18.
  • the control device 18 acquires temperature information from the temperature sensor 17.
  • the temperature of the semiconductor switch 14 is specifically the ambient temperature of the semiconductor switch 14 or the surface temperature of the semiconductor switch 14.
  • the semiconductor switches 14 and 15 when the semiconductor switches 14 and 15 are off, no current flows through the semiconductor switches 14 and 15, and when the semiconductor switches 14 and 15 are on, the current flows between the drain and the source of the semiconductor switch 14.
  • the current value substantially coincides with the current value flowing between the drain and source of the semiconductor switch 15.
  • the on-resistance of the semiconductor switch 14 is substantially the same as the on-resistance of the semiconductor switch 15.
  • the energy consumed by the on-resistance of the semiconductor switch 14 is substantially the same as the energy consumed by the on-resistance of the semiconductor switch 15, so that the temperature of the semiconductor switch 14 substantially matches the temperature of the semiconductor switch 15. Yes. Therefore, detecting the temperature of the semiconductor switch 14 corresponds to detecting the temperature of the semiconductor switch 15, and the temperature sensor 17 corresponds to a temperature sensor detecting the temperature of the semiconductor switch 15.
  • the control device 18 receives an ON signal for instructing to turn on the semiconductor switches 14 and 15 and an OFF signal for instructing to turn off the semiconductor switches 14 and 15.
  • the control device 18 outputs the constant voltage toward the gates of the semiconductor switches 14 and 15 as described above, thereby turning on the semiconductor switches 14 and 15.
  • the control device 18 When the off signal is input, the control device 18 turns off the semiconductor switches 14 and 15 by causing the parasitic capacitors P14 and P15 to discharge as described above. At this time, the controller 18 speeds the parasitic capacitances P14 and P15 to release charges based on the current value indicated by the current information acquired from the current sensor 16 and the temperature indicated by the temperature information acquired from the temperature sensor 17. That is, the speed at which the voltage value across the parasitic capacitances P14 and P15 decreases is adjusted.
  • FIG. 2 is a circuit diagram of the control device 18.
  • the control device 18 includes on switches 20 and 21, a low speed off switch 22, a high speed off switch 23, a low speed circuit 24, a high speed circuit 25, a control unit 26, diodes D1 and D2, and resistors R2, R3,. ., Having R10
  • the control unit 26 has input terminals 26a, 26b, and 26c and output terminals 26d, 26e, and 26f.
  • the on switches 20 and 21 are switches for turning on the semiconductor switches 14 and 15, respectively.
  • the low-speed off switch 22 and the high-speed off switch 23 are switches for turning off the semiconductor switches 14 and 15, respectively.
  • the on switch 20 is a PNP-type bipolar transistor.
  • the on switch 21, the low speed off switch 22, and the high speed off switch 23 are NPN-type bipolar transistors.
  • a predetermined voltage Vc is applied to the emitter of the on switch 20.
  • the anode of the diode D1 is connected to the collector of the on switch 20.
  • the anode of the diode D2 is connected to the cathode of the diode D1.
  • the cathode of the diode D2 is connected to one end of each of the low speed circuit 24 and the high speed circuit 25.
  • one end of each of the low speed circuit 24 and the high speed circuit 25 is connected to the collector of the on switch 20 via the diodes D1 and D2.
  • the collector of the low speed off switch 22 is connected to the other end of the low speed circuit 24.
  • the other end of the high speed circuit 25 is connected to the collector of the high speed off switch 23.
  • the emitters of the low-speed off switch 22 and the high-speed off switch 23 are grounded.
  • the cathode of the diode D1 is further connected to one end of the resistor R2.
  • the other end of the resistor R2 is connected to the gates of the semiconductor switches 14 and 15, respectively. As described above, the gates of the semiconductor switches 14 and 15 are connected to the collector of the ON switch 20 via the diode D1 and the resistor R2.
  • one end of a resistor R3 is connected to the emitter of the on switch 20.
  • the other end of the resistor R3 and one end of the resistor R4 are connected to the base of the on switch 20.
  • the other end of the resistor R4 is connected to the collector of the ON switch 21.
  • One end of each of the resistors R5 and R6 is connected to the base of the on switch 21.
  • the emitter of the on switch 21 and the other end of the resistor R5 are grounded.
  • the other end of the resistor R6 is connected to the output end 26d of the control unit 26.
  • each of resistors R7 and R8 is connected to the base of the low speed off switch 22.
  • the emitter of the low speed off switch 22 and the other end of the resistor R7 are grounded.
  • the other end of the resistor R8 is connected to the output end 26e of the control unit 26.
  • One end of each of the resistors R9 and R10 is connected to the base of the high-speed off switch 23.
  • the emitter of the high-speed off switch 23 and the other end of the resistor R9 are grounded.
  • the other end of the resistor R10 is connected to the output end 26f of the control unit 26.
  • the current sensor 16 and the temperature sensor 17 are connected to the input terminals 26a and 26b of the control unit 26, respectively.
  • An ON signal and an OFF signal are input to the input terminal 26 c of the control unit 26.
  • FIG. 3 is a circuit diagram of the low speed circuit 24.
  • the low speed circuit 24 has a resistor R11. One end of the resistor R11 is connected to the collector of the ON switch 20 via diodes D1 and D2. The other end of the resistor R11 is connected to the collector of the low-speed off switch 22.
  • FIG. 4 is a circuit diagram of the high speed circuit 25.
  • the high speed circuit 25 has a capacitor C1 and a resistor R12. One end of each of the capacitor C1 and the resistor R1 is connected to the collector of the ON switch 20 via diodes D1 and D2. The other end of each of the capacitor C1 and the resistor R12 is connected to the collector of the high-speed off switch 23.
  • the absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24.
  • the on switch 20, the low speed off switch 22, the high speed off switch 23, the low speed circuit 24 and the high speed circuit 25 are respectively a first switch, a first circuit side switch, a second circuit side switch, a first circuit and a first circuit. Functions as two circuits.
  • the emitter and collector of the on switch 20 correspond to one end and the other end of the first switch, respectively.
  • the collector and emitter of the low-speed off switch 22 correspond to one end and the other end of the first circuit side switch.
  • the collector and emitter of the high-speed off switch 23 correspond to one end and the other end of the second circuit side switch.
  • the ON switch 20 when the voltage value of the base with respect to the potential of the emitter is less than the first reference voltage value, a current can flow between the emitter and the collector. At this time, the on switch 20 is on.
  • the first reference voltage value is a negative voltage value.
  • the ON switch 20 when the base voltage value with respect to the emitter potential is equal to or higher than the first reference voltage value, for example, when the base voltage value is zero V, a current flows between the emitter and the collector. Will not flow. At this time, the on switch 20 is off.
  • each of the on switch 21, the low speed off switch 22, and the high speed off switch 23 a current flows between the emitter and the collector when the voltage value of the base with respect to the potential of the emitter is equal to or higher than the second reference voltage value. It becomes possible.
  • each of the on switch 21, the low speed off switch 22, and the high speed off switch 23 is on.
  • the second reference voltage value is a positive voltage value.
  • the base voltage value Is zero V no current flows between the emitter and collector.
  • each of the on switch 21, the low speed off switch 22, and the high speed off switch 23 is off.
  • the control unit 26 is a so-called microcomputer.
  • the control unit 26 outputs a high level voltage and a low level voltage from the output terminals 26d, 26e, and 26f, respectively.
  • the voltage value of the high level voltage is higher than the voltage value of the low level voltage, and the voltage value of the low level voltage is substantially zero V.
  • control unit 26 When the semiconductor switch 14 or 15 is turned on, the control unit 26 outputs a high level voltage, a low level voltage, and a low level voltage from the output terminals 26d, 26e, and 26f, respectively.
  • the on switch 21 When a high level voltage is output from the output terminal 26d, a current flows from the output terminal 26d in the order of the resistors R6 and R5, and a voltage drop occurs at the resistor R5.
  • the on switch 21 the base voltage value based on the emitter potential is equal to or higher than the second reference voltage value, and the on switch 21 is turned on.
  • the on switch 21 When the on switch 21 is turned on, current flows from one end of the resistor R3 to which the voltage Vc is applied in the order of the resistors R3 and R4 and the on switch 21, and a voltage drop occurs in the resistor R3.
  • the on switch 20 the base voltage value based on the emitter potential is less than the first reference voltage value, and the on switch 20 is turned on. From the above, when the high level voltage is output from the output terminal 26d, the ON switch 20 is turned ON.
  • the low speed off switch 22 and the high speed off switch 23 are on, off and off, respectively, current flows from the emitter of the on switch 20 to which the voltage Vc is applied via two current paths. Flowing.
  • One of the two current paths is a current path through which current flows in the order of the on switch 20, the diode D1, the resistor R2, the parasitic capacitance P14, and the resistor R1.
  • the other of the two current paths is a current path through which current flows in the order of the on switch 20, the diode D1, the resistor R2, the parasitic capacitance P15, and the resistor R1.
  • control unit 26 When the semiconductor switches 14 and 15 are turned off, the control unit 26 outputs a low level voltage from the output terminal 26d, outputs a high level voltage from one of the output terminals 26e and 26f, and outputs from the other of the output terminals 26e and 26f. Outputs low level voltage.
  • the parasitic capacitances P14 and P15 are discharged, and the current is supplied from the parasitic capacitances P14 and P15 to the resistor R2.
  • Circuit 24 and low-speed off switch 22 flow in this order.
  • the charges accumulated in the parasitic capacitors P14 and P15 are released, the voltage value across the parasitic capacitors P14 and P15 decreases, and the resistance value between the drain and source of each of the semiconductor switches 14 and 15 increases. To do.
  • the semiconductor switches 14 and 15 are turned off, and the current flowing between the source and drain of each of the semiconductor switches 14 and 15 is cut off.
  • the on switch 20 when the on switch 20, the low speed off switch 22 and the high speed off switch 23 are off, off and on, respectively, the parasitic capacitances P14 and P15 are discharged, and the current is resistance from the parasitic capacitances P14 and P15.
  • the high-speed circuit 25, and the high-speed off switch 23 flow in this order.
  • the charges accumulated in the parasitic capacitors P14 and P15 are released, the voltage value across the parasitic capacitors P14 and P15 decreases, and the resistance value between the drain and source of each of the semiconductor switches 14 and 15 increases. To do.
  • the semiconductor switches 14 and 15 are turned off, and the current flowing between the source and drain of each of the semiconductor switches 14 and 15 is cut off.
  • FIG. 5 is an explanatory diagram of the operation of the control device 18.
  • FIG. 5 shows the transition of the gate voltage value when the low-speed off switch 22 is turned on and the transition of the gate voltage value when the high-speed off switch 23 is turned on for the semiconductor switch 14. ing.
  • the voltage value of the gate of the semiconductor switch 15 changes in the same manner as the voltage value of the gate of the semiconductor switch 14.
  • the vertical axis represents the gate voltage value
  • the horizontal axis represents time.
  • the absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24. For this reason, the on switch 20 and the low speed off switch 22 and the high speed off switch 23 are turned on, off and off, that is, the semiconductor switches 14 and 15 are turned on.
  • the off switch 22 is turned off and on, the rate of decrease in the voltage value across the parasitic capacitances P14 and P15 is slow.
  • the on switch 20 and the low speed off switch 22 are turned off and on, it takes a long time for the semiconductor switches 14 and 15 to turn from on to off, and the electromagnetic waves generated from the semiconductor switches 14 and 15 contain high frequency components. I can't.
  • the control unit 26 when turning off the semiconductor switches 14 and 15, the control unit 26 appropriately selects the switch to be turned on from the low speed off switch 22 and the high speed off switch 23 as described later. By doing so, it is possible to suppress the frequency of generation of electromagnetic waves having high frequency components while maintaining the temperature of the semiconductor switches 14 and 15 within a predetermined range.
  • the high-speed circuit 25 is a parallel circuit of a capacitor C1 and a resistor R12 as shown in FIG.
  • the semiconductor switches 14 and 15 are on, no current flows through the low-speed circuit 24 and the high-speed circuit 25, and no charge is accumulated in the capacitor C ⁇ b> 1 of the high-speed circuit 25. Therefore, immediately after the on switch 20 and the high speed off switch 23 are turned off and on, a large current flows from the parasitic capacitances P14 and P15 to the capacitor C1, and the voltage value between both ends of the parasitic capacitances P14 and P15 is rapid. To drop. For this reason, the semiconductor switches 14 and 15 are turned from on to off in a shorter time.
  • the resistance value between the drain and the source decreases and the value of the current flowing between the drain and the source increases as the gate voltage value increases. For this reason, the value of the current flowing between the drain and the source changes in the same manner as the voltage value of the gate.
  • the control unit 26 includes a CPU (Central Processing Unit) (not shown) and executes a control program stored in a memory (not shown) to turn on the semiconductor switches 14 and 15, and the semiconductor switch 14, And an off process for turning off 15.
  • CPU Central Processing Unit
  • the control unit 26 performs an on process when an on signal is input to the input terminal 26c.
  • the control unit 26 outputs a high level voltage, a low level voltage, and a low level voltage from the output terminals 26d, 26e, and 26f, respectively.
  • the on switch 20, the low speed off switch 22 and the high speed off switch 23 are turned on, off and off, and the semiconductor switches 14 and 15 are turned on.
  • the control unit 26 outputs the high level voltage, the low level voltage, and the low level voltage from the output terminals 26d, 26e, and 26f, respectively, and then ends the ON process.
  • FIG. 6 is a flowchart showing the procedure of the off process executed by the control unit 26.
  • the control unit 26 performs an off process when an off signal is input to the input terminal 26c.
  • the control unit 26 acquires current information input from the current sensor 16 to the input terminal 26a (step S1).
  • the control unit 26 functions as a current information acquisition unit.
  • the control part 26 determines whether the electric current value which the electric current information acquired by step S1 shows is more than a current threshold value (step S2).
  • the current threshold is constant and is stored in advance in the memory described above.
  • the control unit 26 acquires temperature information input from the temperature sensor 17 to the input terminal 26b (step S3).
  • the control unit 26 also functions as a temperature information acquisition unit.
  • the control unit 26 determines whether or not the temperature indicated by the temperature information acquired in step S3 is equal to or higher than a temperature threshold (step S4).
  • the temperature threshold is also constant and is stored in advance in the memory described above.
  • a high temperature indicated by the temperature information means that a current value flowing between the drain and the source of the semiconductor switch 14 is large.
  • the control unit 26 double-checks whether or not a large current is flowing through the semiconductor switches 14 and 15 by executing steps S2 and S4.
  • the control unit 26 When it is determined that the temperature is lower than the temperature threshold (S4: NO), the control unit 26 outputs the low level voltage from the output terminal 26d, thereby turning off the on switch 20 (step S5). Further, the control unit 26 turns on the low speed off switch 22 by outputting a high level voltage from the output terminal 26e (step S6), and outputs a low level voltage from the output terminal 26f to thereby switch on the high speed off. 23 is turned off (step S7). The control unit 26 turns off the semiconductor switches 14 and 15 by executing steps S5 to S7. At this time, it takes a long time for the semiconductor switches 14 and 15 to be turned off, and the electromagnetic waves generated from the semiconductor switches 14 and 15 do not contain high frequency components.
  • the control unit 26 When it is determined that the current value is equal to or higher than the current threshold (S2: YES), or when the temperature is determined to be equal to or higher than the temperature threshold (S4: YES), the control unit 26 generates a low level voltage from the output terminal 26d. By outputting, the on switch 20 is turned off (step S8). Further, the control unit 26 outputs the low-level voltage from the output terminal 26e, thereby turning off the low-speed off switch 22 (Step S9), and outputs the high-level voltage from the output terminal 26f, thereby switching the high-speed off switch. 23 is turned on (step S10). The control unit 26 turns off the semiconductor switches 14 and 15 by executing steps S8 to S10. At this time, the time during which the semiconductor switches 14 and 15 are turned off from on is short, and the switching loss is small. The control unit 26 also functions as a switch control unit.
  • the control unit 26 determines that the current value indicated by the current information acquired from the current sensor 16 is less than the current threshold and the temperature value indicated by the temperature information acquired from the temperature sensor 17 is the temperature.
  • the control unit 26 turns off, on, and off the on switch 20, the low speed off switch 22, and the high speed off switch 23.
  • the semiconductor switches 14 and 15 are turned from off to off over a long time, high frequency components are not included in the electromagnetic waves generated from the semiconductor switches 14 and 15.
  • the switching loss is also small. For this reason, the temperature of the semiconductor switches 14 and 15 is maintained within a predetermined range.
  • the control unit 26 When the current value indicated by the current information acquired from the current sensor 16 is equal to or higher than the current threshold value, or the temperature value indicated by the temperature information acquired from the temperature sensor 17 is equal to or higher than the temperature threshold value, the control unit 26 The value of current flowing between the drains and sources of the switches 14 and 15 is large. Therefore, the control unit 26 turns off, off, and on the on switch 20, the low speed off switch 22, and the high speed off switch 23. At this time, since the semiconductor switches 14 and 15 are quickly turned from on to off, the switching loss is small, and the temperature of the semiconductor switches 14 and 15 is maintained within a predetermined range.
  • the control unit 26 when the control unit 26 appropriately selects the switch to be turned on from the low-speed off switch 22 and the high-speed off switch 23, the switching loss is always small, and the drain and source of each of the semiconductor switches 14 and 15 When the value of the current flowing through the semiconductor switch 14 is large, the semiconductor switches 14 and 15 are turned off from on in a short time, so that electromagnetic waves having a high frequency component are generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
  • the configuration of the power supply system 1 is not limited to a configuration in which the output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11, and the output voltage values of the first battery 10 and the second battery 11
  • a configuration in which the magnitude relationship varies with time may be employed.
  • the semiconductor switches 14 and 15 when the semiconductor switches 14 and 15 are on, when the output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11, the first battery 10 Electric power is supplied to the second battery 11 and the loads 12 and 13, and the second battery 11 stores electricity.
  • the second battery 11 supplies power to the first battery 10 and the loads 12, 13, and the first battery 10
  • the first battery 10 and the second battery 11 supply power to the loads 12 and 13.
  • Each of the loads 12 and 13 operates using electric power supplied from the first battery 10 or the second battery 11.
  • step S1 When the power supply system 1 is configured so that the magnitude relationship between the output voltage values of the first battery 10 and the second battery 11 varies with time, the control unit 26 performs step S1 in step S1 of the off process. It is determined whether or not the absolute value of the current value indicated by the acquired current information is greater than or equal to the current threshold value. When it is determined that the absolute value of the current value is less than the current threshold value, the control unit 26 executes step S3, and when it is determined that the absolute value of the current value is equal to or greater than the current threshold value, the control unit 26 executes step S8.
  • the number of semiconductor switches that the control device 18 turns on or off is not limited to two.
  • the number of semiconductor switches that the control device 18 turns on or off may be one.
  • FIG. 7 is a circuit diagram of the power supply system 3 in the second embodiment.
  • the power supply system 3 is also suitably mounted on the vehicle, like the power supply system 1 in the first embodiment. Similar to the power supply system 1, the power supply system 3 includes a first battery 10, a load 13, a semiconductor switch 14, a current sensor 16, a temperature sensor 17, a control device 18, and a resistor R ⁇ b> 1.
  • the parasitic capacitance P14 is formed between the gate and the source of the semiconductor switch 14.
  • the first battery 10, the semiconductor switch 14, the current sensor 16, the temperature sensor 17, the control device 18, and the resistor R1 are connected in the same manner as in the first embodiment.
  • one end of the load 13 is connected to the source of the semiconductor switch 14. The other end of the load 13 is grounded.
  • the control device 18 turns on and off the semiconductor switch 14 in the same manner as in the first embodiment.
  • the first battery 10 supplies power to the load 13 when the semiconductor switch 14 is on.
  • the semiconductor switch 14 When the semiconductor switch 14 is off, the first battery 10 does not supply power to the load 13 and power supply to the load 13 is stopped.
  • the load 13 operates using the electric power supplied from the first battery 10 when the semiconductor switch 14 is on, and stops operating because the electric power is not supplied when the semiconductor switch 14 is off.
  • FIG. 8 is a circuit diagram of the control device 18. As in the second embodiment, one end of the resistor R2 is connected to the cathode of the diode D1, and the other end of the resistor R2 is connected to the gate of the semiconductor switch 14.
  • the current sensor 16 is connected to the input terminal 26 a of the control unit 26.
  • the temperature sensor 17 is connected to the input end 26 b of the control unit 26.
  • An ON signal and an OFF signal are input to the input terminal 26 c of the control unit 26.
  • the control unit 26 performs an on process and an off process as in the first embodiment. Therefore, the control unit 26 turns on the semiconductor switch 14 by turning on, off, and turning off the on switch 20, the low speed off switch 22, and the high speed off switch 23. Further, when the control unit 26 determines that the value of the current flowing between the drain and gate of the semiconductor switch 14 is less than the current threshold value and the temperature of the semiconductor switch 14 is less than the temperature threshold value, The low-speed off switch 22 and the high-speed off switch 23 are turned off, on, and off, respectively, and the semiconductor switch 14 is turned off. As a result, the semiconductor switch 14 is turned from on to off over a long time, and the electromagnetic wave generated from the semiconductor switch 14 does not contain a high frequency component.
  • control unit 26 determines that the value of the current flowing between the drain and gate of the semiconductor switch 14 is equal to or higher than the current threshold value, or the temperature of the semiconductor switch 14 is equal to or higher than the temperature threshold value.
  • the low-speed off switch 22 and the high-speed off switch 23 are turned off, off, and on, respectively, and the semiconductor switch 14 is turned off. Thereby, the semiconductor switch 14 is quickly turned from on to off, so that the switching loss is small and the temperature of the semiconductor switch 14 is maintained within a predetermined range.
  • control device 18 in the second embodiment The circuit configuration of the control device 18 in the second embodiment is the same as that in the first embodiment, and as described above, the control unit 26 in the second embodiment performs an on process and an off process as in the first embodiment. For this reason, the control apparatus 18 in Embodiment 2 has the same effect as Embodiment 1.
  • FIG. 1 The circuit configuration of the control device 18 in the second embodiment is the same as that in the first embodiment, and as described above, the control unit 26 in the second embodiment performs an on process and an off process as in the first embodiment. For this reason, the control apparatus 18 in Embodiment 2 has the same effect as Embodiment 1. FIG.
  • the constituent part of the low-speed circuit 24 is not limited to the resistor R11, and the constituent part of the high-speed circuit 25 is not limited to the parallel circuit of the capacitor C1 and the resistor R12. It is only necessary that the absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24.
  • each of the low-speed circuit 24 and the high-speed circuit 25 has at least one of a capacitor and a resistor.
  • the control unit 26 of the control device 18 determines whether or not the current value (absolute value) is equal to or higher than the current threshold, and the temperature is equal to or higher than the temperature threshold. Only one of the temperature determinations may be performed.
  • the control unit 26 performs only current determination, in the off process, when the control unit 26 determines that the current value (absolute value) is less than the current threshold value (S2: NO), it executes Step S5.
  • the control unit 26 performs only the temperature determination, in the off process, the control unit 26 starts the process from step S3 without executing steps S1 and S2. As described above, even when the control unit 26 performs the off process, it is possible to suppress the frequency of generation of electromagnetic waves having high frequency components while maintaining the temperature of the semiconductor switch within a predetermined range.
  • the semiconductor switches 14 and 15 are not limited to FETs, but may be IGBTs (Insulated Gate Bipolar Transistors), for example.
  • Control device 1415 Semiconductor switch 20 ON switch (first switch) 22 Low speed off switch (1st circuit side switch) 23 High speed off switch (2nd circuit side switch) 24 Low speed circuit (first circuit) 25 High-speed circuit (second circuit) 26 Control unit (current information acquisition unit, temperature information acquisition unit, switch control unit)

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  • Electronic Switches (AREA)

Abstract

In each of semiconductor switches (14, 15), a resistance value between a drain and a source decreases in response to an increase in the voltage value of a gate. In a control device (18), a predetermined voltage Vc is applied to an emitter of an on switch (20). One end of each of a low speed circuit (24) and a high speed circuit (25) is connected to a collector of the on switch (20). Collectors of a low-speed off switch (22) and a high-speed off switch (23) are respectively connected to the other ends of the low speed circuit (24) and the high speed circuit (25). Gates of the semiconductor switches (14, 15) are connected to the collector of the on switch (20). The absolute value of the impedance of the high speed circuit (25) is smaller than the absolute value of the impedance of the low speed circuit (24).

Description

制御装置Control device
　本発明は、半導体スイッチのオン及びオフを行う制御装置に関する。 The present invention relates to a control device for turning on and off a semiconductor switch.
　現在、車両に搭載されている電源システムとして、２つのバッテリの正極間がスイッチによって接続されている電源システムが普及している。このように２つのバッテリを備える電源システムの中には、２つのバッテリの正極間を接続するスイッチとして、機械的にオン及びオフが行われる機械スイッチよりも、小型、かつ、軽量である半導体トランジスタ、例えばＦＥＴ(Field Effective Transistor)が用いられる電源システムがある。 Currently, as a power supply system mounted on a vehicle, a power supply system in which the positive electrodes of two batteries are connected by a switch is widespread. Thus, in a power supply system including two batteries, a semiconductor transistor that is smaller and lighter than a mechanical switch that is mechanically turned on and off as a switch that connects the positive electrodes of the two batteries. For example, there is a power supply system in which an FET (Field Effective Transistor) is used.
　このような半導体スイッチは、第１端、第２端及び第３端を有し、第１端の電圧値に応じて、２つのバッテリの正極夫々に接続される第２端及び第３端間の抵抗値が調整される。半導体スイッチがＦＥＴである場合、第１端はゲートであり、第２端はドレイン及びソースの一方であり、第３端はドレイン及びソースの他方である。第１端の電圧値を調整することによって、電流が流れる第２端及び第３端間の抵抗値を調整し、半導体スイッチをオン又はオフにする。 Such a semiconductor switch has a first end, a second end, and a third end, and is connected between the second end and the third end connected to the positive electrodes of the two batteries according to the voltage value of the first end. Is adjusted. When the semiconductor switch is an FET, the first end is a gate, the second end is one of a drain and a source, and the third end is the other of the drain and the source. By adjusting the voltage value of the first end, the resistance value between the second end and the third end through which the current flows is adjusted, and the semiconductor switch is turned on or off.
　特許文献１には、半導体スイッチ、具体的には、Ｎチャネル型のＦＥＴのオン及びオフを行う制御装置が開示されている。この制御装置は、半導体スイッチの第１端の電圧値を一定の電圧値以上に調整することによって半導体スイッチをオンにし、半導体スイッチの第１端の電圧値を一定の電圧値未満に調整することによって半導体スイッチをオフにする。 Patent Document 1 discloses a control device for turning on and off a semiconductor switch, specifically, an N-channel FET. The control device turns on the semiconductor switch by adjusting the voltage value at the first end of the semiconductor switch to a certain voltage value or more, and adjusts the voltage value at the first end of the semiconductor switch to be less than the certain voltage value. To turn off the semiconductor switch.
特開２０１４－１７７２２９号公報JP 2014-177229 A
　第２端及び第３端間に電流が流れている半導体スイッチがオンからオフになる過程では、第２端及び第３端間の抵抗値が上昇し、第２端及び第３端間を流れる電流値が低下する。このとき、半導体スイッチではスイッチング損失が発生する。スイッチング損失は、抵抗値及び電流値の積を、半導体スイッチがオンからオフとなる期間に亘って積分することによって算出される。 In the process in which the semiconductor switch in which current flows between the second end and the third end is turned off from on, the resistance value between the second end and the third end increases and flows between the second end and the third end. The current value decreases. At this time, switching loss occurs in the semiconductor switch. The switching loss is calculated by integrating the product of the resistance value and the current value over a period during which the semiconductor switch is turned off.
　スイッチング損失が発生した場合、半導体スイッチは発熱する。このとき、半導体スイッチの温度の上昇幅はスイッチング損失が大きい程、大きい。半導体スイッチが高温になることを防止するためには、半導体スイッチを素早くオンからオフにすることによって、スイッチング損失を小さくし、半導体スイッチの温度を所定範囲内に維持する必要がある。 】 When a switching loss occurs, the semiconductor switch generates heat. At this time, the temperature rise of the semiconductor switch is larger as the switching loss is larger. In order to prevent the semiconductor switch from reaching a high temperature, it is necessary to reduce the switching loss and maintain the temperature of the semiconductor switch within a predetermined range by quickly turning the semiconductor switch from on to off.
　また、半導体スイッチがオンからオフとなった場合、第２端及び第３端間を流れる電流値が変化するため、半導体スイッチから電磁波が発生する。ここで、半導体スイッチがオンからオフとなる速度が速い程、第２端及び第３端間を流れる電流値が急峻に変化するため、高周波数成分を有する電磁波が発生する。このとき、半導体スイッチの周辺機器は、電磁波が制御信号と干渉することによって誤動作する可能性がある。周辺機器が誤動作する確率を低くするためには、高周波数成分を有する電磁波が発生する頻度を抑制する必要がある。 In addition, when the semiconductor switch is turned from on to off, the value of the current flowing between the second end and the third end changes, so that an electromagnetic wave is generated from the semiconductor switch. Here, as the speed at which the semiconductor switch is turned from on to off is higher, the value of the current flowing between the second end and the third end changes more rapidly, so that an electromagnetic wave having a high frequency component is generated. At this time, the peripheral device of the semiconductor switch may malfunction due to interference of the electromagnetic wave with the control signal. In order to reduce the probability that a peripheral device malfunctions, it is necessary to suppress the frequency with which electromagnetic waves having high-frequency components are generated.
　以上のことから、半導体スイッチのオン及びオフを行う制御装置には、半導体スイッチの温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制しなければならないという問題がある。 From the above, there is a problem in the control device that turns on and off the semiconductor switch that it is necessary to suppress the frequency of generation of electromagnetic waves having high frequency components while maintaining the temperature of the semiconductor switch within a predetermined range. is there.
　本発明は斯かる事情に鑑みてなされたものであり、その目的とするところは、半導体スイッチの温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制することが可能な制御装置を提供することにある。 The present invention has been made in view of such circumstances, and its object is to suppress the frequency of generation of electromagnetic waves having high-frequency components while maintaining the temperature of the semiconductor switch within a predetermined range. It is to provide a possible control device.
　本発明に係る制御装置は、第１端、第２端及び第３端を有し、前記第１端の電圧値の上昇に応じて、前記第２端及び第３端間の抵抗値が低下する半導体スイッチのオン及びオフを行う制御装置において、一端に所定の電圧が印加され、他端に前記半導体スイッチの前記第１端が接続されている第１スイッチと、該第１スイッチの他端に一端が接続されている第１回路と、該第１回路の他端に一端が接続されている第１回路側スイッチと、前記第１スイッチの他端に一端が接続され、インピーダンスの絶対値が前記第１回路のインピーダンスの絶対値よりも小さい第２回路と、該第２回路の他端に一端が接続されている第２回路側スイッチとを備えることを特徴とする。 The control device according to the present invention has a first end, a second end, and a third end, and the resistance value between the second end and the third end decreases as the voltage value of the first end increases. In a control device for turning on and off a semiconductor switch, a first switch having a predetermined voltage applied to one end and the first end of the semiconductor switch connected to the other end, and the other end of the first switch A first circuit having one end connected to the first circuit, a first circuit-side switch having one end connected to the other end of the first circuit, an end connected to the other end of the first switch, and an absolute value of impedance The second circuit has a second circuit smaller than the absolute value of the impedance of the first circuit, and a second circuit side switch having one end connected to the other end of the second circuit.
　本発明にあっては、第１スイッチの一端には所定の電圧が印加され、第１スイッチの他端には、第１回路及び第２回路夫々の一端が接続されている。第１回路及び第２回路夫々の他端には、第１回路側スイッチ及び第２回路側スイッチの一端が接続されている。第１回路側スイッチ及び第２回路側スイッチ夫々の他端は、例えば接地されている。第１スイッチの他端には、半導体スイッチの第１端に接続されている。半導体スイッチにおいては、第１端の電圧値が上昇した場合、第２端及び第３端間の抵抗値は低下する。また、第２回路のインピーダンスの絶対値は、第１回路のインピーダンスの絶対値よりも小さい。 In the present invention, a predetermined voltage is applied to one end of the first switch, and one end of each of the first circuit and the second circuit is connected to the other end of the first switch. One ends of the first circuit side switch and the second circuit side switch are connected to the other ends of the first circuit and the second circuit, respectively. The other ends of the first circuit side switch and the second circuit side switch are grounded, for example. The other end of the first switch is connected to the first end of the semiconductor switch. In the semiconductor switch, when the voltage value at the first end increases, the resistance value between the second end and the third end decreases. The absolute value of the impedance of the second circuit is smaller than the absolute value of the impedance of the first circuit.
　以上のように構成された装置では、第１スイッチ、第１回路側スイッチ及び第２回路側スイッチがオン、オフ及びオフとなった場合、所定の電圧が印加されている第１スイッチの一端から、第１スイッチを介して、半導体スイッチの第１端に一端が接続されている寄生容量に電流が流れ、寄生容量に電荷が蓄積される。電荷が蓄積されるにつれて、寄生容量の両端間の電圧が上昇し、第１端の電圧値が上昇する。これにより、半導体スイッチの第２端及び第３端間の抵抗値が低下し、半導体スイッチはオンとなる。 In the device configured as described above, when the first switch, the first circuit side switch, and the second circuit side switch are turned on, off, and off, from one end of the first switch to which a predetermined voltage is applied. Through the first switch, a current flows through a parasitic capacitor having one end connected to the first end of the semiconductor switch, and charges are accumulated in the parasitic capacitor. As charge is accumulated, the voltage across the parasitic capacitance rises and the voltage value at the first end rises. As a result, the resistance value between the second end and the third end of the semiconductor switch decreases, and the semiconductor switch is turned on.
　第１スイッチがオフとなり、かつ、第１回路側スイッチ及び第２回路側スイッチの一方がオンとなった場合、寄生容量から電流が第１回路又は第２回路を介して流れ、寄生容量の両端間の電圧値と共に第１端の電圧値が低下する。第１端の電圧値が低下することによって、半導体スイッチの第２端及び第３端間の抵抗値が上昇し、半導体スイッチはオフとなる。ここで、第２回路のインピーダンスの絶対値は、第１回路のインピーダンスの絶対値よりも小さい。このため、第１回路側スイッチをオンにした場合における寄生容量の両端間の電圧値の低下速度は遅く、第２回路側スイッチをオンにした場合における寄生容量の両端間の電圧値の低下速度は速い。 When the first switch is turned off and one of the first circuit side switch and the second circuit side switch is turned on, a current flows from the parasitic capacitance through the first circuit or the second circuit, and both ends of the parasitic capacitance. The voltage value at the first end decreases with the voltage value between. As the voltage value at the first end decreases, the resistance value between the second end and the third end of the semiconductor switch increases, and the semiconductor switch is turned off. Here, the absolute value of the impedance of the second circuit is smaller than the absolute value of the impedance of the first circuit. For this reason, when the first circuit side switch is turned on, the rate of decrease in the voltage value across the parasitic capacitance is slow, and when the second circuit side switch is turned on, the rate of decrease in the voltage value across the parasitic capacitance is reduced. Is fast.
　従って、第１回路側スイッチをオンにした場合に半導体スイッチがオンからオフとなる時間は長く、第２回路側スイッチをオンにした場合に半導体スイッチがオンからオフとなる時間は短い。言い換えると、第１回路側スイッチをオンにした場合、半導体スイッチから発生する電磁波には高周波数成分が含まれず、第２回路側スイッチをオンにした場合、スイッチング損失が小さい。以上のことから、半導体スイッチをオフにする場合に、第１回路側スイッチ及び第２回路側スイッチの中からオンにするスイッチを適切に選択することによって、半導体スイッチの温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制することが可能となる。 Therefore, when the first circuit side switch is turned on, the time for the semiconductor switch to turn off is long, and when the second circuit side switch is turned on, the time for the semiconductor switch to turn from on to off is short. In other words, when the first circuit side switch is turned on, the electromagnetic wave generated from the semiconductor switch does not include a high frequency component, and when the second circuit side switch is turned on, the switching loss is small. From the above, when the semiconductor switch is turned off, the temperature of the semiconductor switch is maintained within a predetermined range by appropriately selecting the switch to be turned on from the first circuit side switch and the second circuit side switch. However, it is possible to suppress the frequency with which electromagnetic waves having high-frequency components are generated.
　本発明に係る制御装置は、前記第２端及び第３端間を流れる電流値を示す電流情報を取得する電流情報取得部と、前記電流情報取得部が取得した電流情報が示す電流値が電流閾値未満である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オン及びオフにし、前記電流情報取得部が取得した電流情報が示す電流値が電流閾値以上である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オフ及びオンにするスイッチ制御部とを備えることを特徴とする。 The control device according to the present invention includes a current information acquisition unit that acquires current information indicating a current value flowing between the second end and the third end, and a current value indicated by the current information acquired by the current information acquisition unit is a current value. When it is less than the threshold value, the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off, and the current value indicated by the current information acquired by the current information acquisition unit is equal to or greater than the current threshold value. In this case, a switch control unit that turns off, off, and on each of the first switch, the first circuit side switch, and the second circuit side switch is provided.
　本発明にあっては、半導体スイッチの第２端及び第３端間を流れる電流値を示す電流情報を取得する。取得した電流情報が示す電流値が電流閾値未満である場合、大きなスイッチング損失が発生しにくいため、第１スイッチ、第１回路側スイッチ及び第２回路側スイッチをオフ、オン及びオフにする。このとき、半導体スイッチは長い時間をかけてオンからオフとなるため、半導体スイッチから発生する電磁波に高周波数成分は含まれない。また、半導体スイッチの第２端及び第３端間に流れる電流値が小さいので、スイッチング損失も小さく、半導体スイッチの温度が所定範囲内に維持される。 In the present invention, current information indicating a current value flowing between the second end and the third end of the semiconductor switch is acquired. When the current value indicated by the acquired current information is less than the current threshold, a large switching loss is unlikely to occur, so the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off. At this time, since the semiconductor switch is turned on from off over a long time, high frequency components are not included in the electromagnetic wave generated from the semiconductor switch. Further, since the value of the current flowing between the second end and the third end of the semiconductor switch is small, the switching loss is also small and the temperature of the semiconductor switch is maintained within a predetermined range.
　また、取得した電流情報が示す電流値が電流閾値以上である場合、半導体スイッチの第２端及び第３端間を流れる電流値が大きいため、第１スイッチ、第１回路側スイッチ及び第２回路側スイッチをオフ、オフ及びオンにする。このとき、半導体スイッチは素早くオンからオフとなるため、スイッチング損失は小さく、半導体スイッチの温度が所定範囲内に維持される。 In addition, when the current value indicated by the acquired current information is equal to or greater than the current threshold value, the current value flowing between the second end and the third end of the semiconductor switch is large, so the first switch, the first circuit side switch, and the second circuit Turn the side switch off, off and on. At this time, since the semiconductor switch is quickly turned from on to off, the switching loss is small and the temperature of the semiconductor switch is maintained within a predetermined range.
　以上のように、第１回路側スイッチ及び第２回路側スイッチの中からオンにするスイッチを適切に選択した場合、スイッチング損失は常に小さく、半導体スイッチの第２端及び第３端を流れる電流値が大きいとき、短い時間で半導体スイッチがオンからオフとなるので、高周波数成分を有する電磁波が発生する。このため、半導体スイッチの温度が所定範囲内に維持され、高周波数成分を有する電磁波が発生する頻度は小さい。 As described above, when the switch to be turned on is appropriately selected from the first circuit side switch and the second circuit side switch, the switching loss is always small, and the current value flowing through the second end and the third end of the semiconductor switch When is large, the semiconductor switch is turned off from on in a short time, so that an electromagnetic wave having a high frequency component is generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
　本発明に係る制御装置は、前記半導体スイッチの温度を示す温度情報を取得する温度情報取得部と、前記温度情報取得部が取得した温度情報が示す温度が温度閾値未満である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オン及びオフにし、前記温度情報取得部が取得した温度情報が示す温度が温度閾値以上である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オフ及びオンにするスイッチ制御部とを備えることを特徴とする。 The control device according to the present invention includes a temperature information acquisition unit that acquires temperature information indicating a temperature of the semiconductor switch, and the temperature indicated by the temperature information acquired by the temperature information acquisition unit is less than a temperature threshold. 1 switch, the first circuit side switch and the second circuit side switch are turned off, on and off, respectively, and when the temperature indicated by the temperature information acquired by the temperature information acquisition unit is equal to or higher than a temperature threshold, the first switch, And a switch controller that turns off, off, and on each of the first circuit side switch and the second circuit side switch.
　本発明にあっては、半導体スイッチの第２端及び第３端間を流れている電流値が上昇した場合、半導体スイッチのオン抵抗で熱として消費されるエネルギーが上昇し、半導体スイッチの温度が上昇する。取得した温度情報が示す温度が温度閾値未満である場合、大きなスイッチング損失が発生しにくいため、第１スイッチ、第１回路側スイッチ及び第２回路側スイッチをオフ、オン及びオフにする。このとき、半導体スイッチは長い時間をかけてオンからオフとなるため、半導体スイッチから発生する電磁波に高周波数成分は含まれない。また、半導体スイッチの第２端及び第３端間に流れる電流値が小さいので、スイッチング損失も小さく、半導体スイッチの温度が所定範囲内に維持される。 In the present invention, when the current value flowing between the second end and the third end of the semiconductor switch increases, the energy consumed as heat by the on-resistance of the semiconductor switch increases, and the temperature of the semiconductor switch To rise. When the temperature indicated by the acquired temperature information is less than the temperature threshold, a large switching loss is unlikely to occur, so the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off. At this time, since the semiconductor switch is turned on from off over a long time, high frequency components are not included in the electromagnetic wave generated from the semiconductor switch. Further, since the value of the current flowing between the second end and the third end of the semiconductor switch is small, the switching loss is also small and the temperature of the semiconductor switch is maintained within a predetermined range.
　また、取得した温度情報が示す温度が温度閾値以上である場合、半導体スイッチの第２端及び第３端間を流れる電流値が大きいため、第１スイッチ、第１回路側スイッチ及び第２回路側スイッチをオフ、オフ及びオンにする。このとき、半導体スイッチは素早くオンからオフとなるため、スイッチング損失は小さく、半導体スイッチの温度が所定範囲内に維持される。 In addition, when the temperature indicated by the acquired temperature information is equal to or higher than the temperature threshold value, the current value flowing between the second end and the third end of the semiconductor switch is large, so the first switch, the first circuit side switch, and the second circuit side Turn the switch off, off and on. At this time, since the semiconductor switch is quickly turned from on to off, the switching loss is small and the temperature of the semiconductor switch is maintained within a predetermined range.
　以上のように、第１回路側スイッチ及び第２回路側スイッチの中からオンにするスイッチを適切に選択した場合、スイッチング損失は常に小さく、半導体スイッチの第２端及び第３端を流れる電流値が大きいとき、短い時間で半導体スイッチがオンからオフとなるので、高周波数成分を有する電磁波が発生する。このため、半導体スイッチの温度が所定範囲内に維持され、高周波数成分を有する電磁波が発生する頻度は小さい。 As described above, when the switch to be turned on is appropriately selected from the first circuit side switch and the second circuit side switch, the switching loss is always small, and the current value flowing through the second end and the third end of the semiconductor switch When is large, the semiconductor switch is turned off from on in a short time, so that an electromagnetic wave having a high frequency component is generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
　本発明によれば、半導体スイッチの温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制することが可能である。 According to the present invention, it is possible to suppress the frequency with which electromagnetic waves having high frequency components are generated while maintaining the temperature of the semiconductor switch within a predetermined range.
実施の形態１における電源システムの回路図である。1 is a circuit diagram of a power supply system in Embodiment 1. FIG. 制御装置の回路図である。It is a circuit diagram of a control device. 低速用回路の回路図である。It is a circuit diagram of a circuit for low speed. 高速用回路の回路図である。It is a circuit diagram of the circuit for high speed. 制御装置の動作の説明図である。It is explanatory drawing of operation | movement of a control apparatus. 制御部が実行するオフ処理の手順を示すフローチャートである。It is a flowchart which shows the procedure of the OFF process which a control part performs. 実施の形態２における電源システムの回路図である。6 is a circuit diagram of a power supply system according to Embodiment 2. FIG. 制御装置の回路図である。It is a circuit diagram of a control device.
　以下、本発明をその実施の形態を示す図面に基づいて詳述する。
（実施の形態１）
　図１は、実施の形態１における電源システム１の回路図である。電源システム１は、好適に車両に搭載され、第１バッテリ１０、第２バッテリ１１、負荷１２，１３、半導体スイッチ１４，１５、電流センサ１６、温度センサ１７、制御装置１８及び抵抗Ｒ１を備える。半導体スイッチ１４，１５夫々は、Ｎチャネル型のＦＥＴであり、ゲート、ドレイン及びソースを有する。半導体スイッチ１４のゲート及びソース間には寄生容量Ｐ１４が形成されており、半導体スイッチ１５のゲート及びソース間にも寄生容量Ｐ１５が形成されている。 Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof.
(Embodiment 1)
FIG. 1 is a circuit diagram of a power supply system 1 according to the first embodiment. The power supply system 1 is suitably mounted on a vehicle and includes a first battery 10, a second battery 11, loads 12, 13, semiconductor switches 14, 15, a current sensor 16, a temperature sensor 17, a control device 18, and a resistor R1. Each of the semiconductor switches 14 and 15 is an N-channel FET and has a gate, a drain, and a source. A parasitic capacitance P14 is formed between the gate and source of the semiconductor switch 14, and a parasitic capacitance P15 is also formed between the gate and source of the semiconductor switch 15.
　第１バッテリ１０の正極には、負荷１２の一端と、半導体スイッチ１４のドレインとが接続されている。半導体スイッチ１４のソースは半導体スイッチ１５のソースに接続されている。半導体スイッチ１５のドレインは、第２バッテリ１１の正極と、負荷１３の一端とに接続されている。第１バッテリ１０及び第２バッテリ１１夫々の負極と、負荷１２，１３夫々の他端とは接地されている。半導体スイッチ１４のソースには、更に、抵抗Ｒ１の一端が接続されている。抵抗Ｒ１の他端は接地されている。半導体スイッチ１４，１５夫々のゲートと、電流センサ１６と、温度センサ１７とは制御装置１８に各別に接続されている。 One end of the load 12 and the drain of the semiconductor switch 14 are connected to the positive electrode of the first battery 10. The source of the semiconductor switch 14 is connected to the source of the semiconductor switch 15. The drain of the semiconductor switch 15 is connected to the positive electrode of the second battery 11 and one end of the load 13. The negative electrodes of the first battery 10 and the second battery 11 and the other ends of the loads 12 and 13 are grounded. One end of a resistor R 1 is further connected to the source of the semiconductor switch 14. The other end of the resistor R1 is grounded. The gates of the semiconductor switches 14 and 15, the current sensor 16, and the temperature sensor 17 are individually connected to the control device 18.
　半導体スイッチ１４，１５夫々について、ソースの電位を基準としたゲートの電圧値の上昇に応じて、ドレイン及びソース間の抵抗値が低下する。半導体スイッチ１４，１５夫々のオン及びオフは制御装置１８によって行われる。
　半導体スイッチ１４，１５夫々について、ゲートが第１端に相当し、ドレイン及びソースの中で、一方が第２端に相当し、他方が第３端に相当する。 For each of the semiconductor switches 14 and 15, the resistance value between the drain and the source decreases as the gate voltage value increases with the source potential as a reference. Each of the semiconductor switches 14 and 15 is turned on and off by the control device 18.
In each of the semiconductor switches 14 and 15, the gate corresponds to the first end, and one of the drain and the source corresponds to the second end, and the other corresponds to the third end.
　制御装置１８は、半導体スイッチ１４をオンにする場合、一定の電圧を半導体スイッチ１４のゲートに向けて出力する。これにより、電流が寄生容量Ｐ１４及び抵抗Ｒ１の順に流れ、寄生容量Ｐ１４に電荷が蓄積される。電荷の蓄積によって、寄生容量Ｐ１４の両端間の電圧値、即ち、ソースの電位を基準としたゲートの電圧値が上昇し、半導体スイッチ１４のドレイン及びソース間の抵抗値が低下する。結果、半導体スイッチ１４がオンとなり、半導体スイッチ１４のソース及びドレイン間に電流が流れることが可能となる。 When the semiconductor switch 14 is turned on, the control device 18 outputs a constant voltage toward the gate of the semiconductor switch 14. As a result, current flows in the order of the parasitic capacitance P14 and the resistor R1, and charges are accumulated in the parasitic capacitance P14. Due to the charge accumulation, the voltage value between both ends of the parasitic capacitance P14, that is, the gate voltage value based on the source potential increases, and the resistance value between the drain and source of the semiconductor switch 14 decreases. As a result, the semiconductor switch 14 is turned on, and a current can flow between the source and drain of the semiconductor switch 14.
　制御装置１８は、半導体スイッチ１４をオフにする場合、寄生容量Ｐ１４に放電を行わせる。これにより、寄生容量Ｐ１４に蓄積されていた電荷が放出される。電荷の放出によって、寄生容量Ｐ１４の両端間の電圧値が低下し、半導体スイッチ１４のドレイン及びソース間の抵抗値が上昇する。結果、半導体スイッチ１４がオフとなり、半導体スイッチ１４のソース及びドレイン間に流れる電流が遮断される。 The control device 18 causes the parasitic capacitance P14 to discharge when the semiconductor switch 14 is turned off. As a result, the charge accumulated in the parasitic capacitance P14 is released. Due to the discharge of the charge, the voltage value across the parasitic capacitance P14 decreases, and the resistance value between the drain and source of the semiconductor switch 14 increases. As a result, the semiconductor switch 14 is turned off, and the current flowing between the source and drain of the semiconductor switch 14 is interrupted.
　制御装置１８は、半導体スイッチ１４と同様に、半導体スイッチ１５をオン又はオフにする。制御装置１８が半導体スイッチ１４をオン又はオフにする構成の説明において、半導体スイッチ１４及び寄生容量Ｐ１４夫々を半導体スイッチ１５及び寄生容量Ｐ１５に置き換えることによって、制御装置１８が半導体スイッチ１５をオン又はオフする構成を説明することができる。 The control device 18 turns on or off the semiconductor switch 15 similarly to the semiconductor switch 14. In the description of the configuration in which the control device 18 turns the semiconductor switch 14 on or off, the control device 18 turns the semiconductor switch 15 on or off by replacing the semiconductor switch 14 and the parasitic capacitance P14 with the semiconductor switch 15 and the parasitic capacitance P15, respectively. The structure to perform can be described.
　制御装置１８は、半導体スイッチ１４，１５を略同時にオンにし、半導体スイッチ１４，１５を略同時にオフにする。
　なお、半導体スイッチ１４のソースは半導体スイッチ１５のソースに接続されているため、半導体スイッチ１４，１５がオフである場合に、半導体スイッチ１４，１５夫々の図示しない寄生ダイオードを介して電流が流れることはない。 The control device 18 turns on the semiconductor switches 14 and 15 substantially simultaneously and turns off the semiconductor switches 14 and 15 substantially simultaneously.
Since the source of the semiconductor switch 14 is connected to the source of the semiconductor switch 15, when the semiconductor switches 14 and 15 are off, a current flows through parasitic diodes (not shown) of the semiconductor switches 14 and 15, respectively. There is no.
　第１バッテリ１０は例えばリチウムイオン電池である。第１バッテリ１０の出力電圧値は第２バッテリ１１の出力電圧値よりも高い。第１バッテリ１０は、車両のエンジンと連動して発電する図示しない発電機が発生した電力を蓄える。第１バッテリ１０は、半導体スイッチ１４，１５がオンである場合、第２バッテリ１１及び負荷１２，１３に電力を供給する。第１バッテリ１０は、半導体スイッチ１４，１５がオフである場合、負荷１２に電力を供給し、第２バッテリ１１及び負荷１３に電力を供給することはない。 The first battery 10 is, for example, a lithium ion battery. The output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11. The first battery 10 stores electric power generated by a generator (not shown) that generates power in conjunction with the vehicle engine. The first battery 10 supplies power to the second battery 11 and the loads 12 and 13 when the semiconductor switches 14 and 15 are on. When the semiconductor switches 14 and 15 are off, the first battery 10 supplies power to the load 12 and does not supply power to the second battery 11 and the load 13.
　第２バッテリ１１は例えば鉛蓄電池である。前述したように、半導体スイッチ１４，１５がオンである場合、第１バッテリ１０から第２バッテリ１１に電力が供給され、第２バッテリ１１は蓄電する。半導体スイッチ１４，１５がオフである場合、第２バッテリ１１は電力を負荷１３に供給する。 The second battery 11 is, for example, a lead storage battery. As described above, when the semiconductor switches 14 and 15 are on, power is supplied from the first battery 10 to the second battery 11 and the second battery 11 stores electricity. When the semiconductor switches 14 and 15 are off, the second battery 11 supplies power to the load 13.
　負荷１２，１３夫々は車両に搭載されている電気機器である。負荷１２は、第１バッテリ１０から供給された電力を用いて作動する。負荷１３は、半導体スイッチ１４，１５がオンである場合、第１バッテリ１０から供給された電力を用いて作動し、半導体スイッチ１４，１５がオフである場合、第２バッテリ１１から供給された電力を用いて作動する。 Each of the loads 12 and 13 is an electric device mounted on the vehicle. The load 12 operates using the electric power supplied from the first battery 10. The load 13 operates using the power supplied from the first battery 10 when the semiconductor switches 14 and 15 are on, and the power supplied from the second battery 11 when the semiconductor switches 14 and 15 are off. Operates with.
　電流センサ１６は半導体スイッチ１４のドレイン及びソース間を流れる電流値を検出する。電流センサ１６は、検出した電流値、即ち、半導体スイッチ１４のドレイン及びソース間を流れる電流値を示す電流情報を制御装置１８に出力する。制御装置１８は、電流センサ１６から電流情報を取得する。
　なお、抵抗Ｒ１の抵抗値は、半導体スイッチ１４，１５夫々のオン抵抗の合成抵抗値よりも十分に大きい。このため、半導体スイッチ１４，１５がオンである場合、半導体スイッチ１４のドレイン及びソース間に流れる電流値は、半導体スイッチ１５のドレイン及びソース間に流れる電流値と略一致している。 The current sensor 16 detects the value of current flowing between the drain and source of the semiconductor switch 14. The current sensor 16 outputs current information indicating the detected current value, that is, the current value flowing between the drain and source of the semiconductor switch 14 to the control device 18. The control device 18 acquires current information from the current sensor 16.
The resistance value of the resistor R1 is sufficiently larger than the combined resistance value of the on-resistances of the semiconductor switches 14 and 15. For this reason, when the semiconductor switches 14 and 15 are on, the value of the current flowing between the drain and the source of the semiconductor switch 14 substantially matches the value of the current flowing between the drain and the source of the semiconductor switch 15.
　温度センサ１７は、例えばサーミスタによって構成され、半導体スイッチ１４の温度を検出する。温度センサ１７は、検出した温度、即ち、半導体スイッチ１４の温度を示す温度情報を制御装置１８に出力する。制御装置１８は、温度センサ１７から温度情報を取得する。半導体スイッチ１４の温度は、具体的には、半導体スイッチ１４の周辺温度、又は、半導体スイッチ１４の表面温度等である。 The temperature sensor 17 is constituted by a thermistor, for example, and detects the temperature of the semiconductor switch 14. The temperature sensor 17 outputs temperature information indicating the detected temperature, that is, the temperature of the semiconductor switch 14 to the control device 18. The control device 18 acquires temperature information from the temperature sensor 17. The temperature of the semiconductor switch 14 is specifically the ambient temperature of the semiconductor switch 14 or the surface temperature of the semiconductor switch 14.
　前述したように、半導体スイッチ１４，１５がオフである場合、半導体スイッチ１４，１５に電流は流れることはなく、半導体スイッチ１４，１５がオンである場合、半導体スイッチ１４のドレイン及びソース間に流れる電流値は、半導体スイッチ１５のドレイン及びソース間に流れる電流値と略一致している。更に、半導体スイッチ１４のオン抵抗は半導体スイッチ１５のオン抵抗と略一致している。このため、半導体スイッチ１４のオン抵抗で消費されるエネルギーは、半導体スイッチ１５のオン抵抗で消費されるエネルギーと略同じであるので、半導体スイッチ１４の温度は半導体スイッチ１５の温度に略一致している。従って、半導体スイッチ１４の温度を検出することは、半導体スイッチ１５の温度を検出することに相当し、温度センサ１７は半導体スイッチ１５の温度を検出する温度センサに相当する。 As described above, when the semiconductor switches 14 and 15 are off, no current flows through the semiconductor switches 14 and 15, and when the semiconductor switches 14 and 15 are on, the current flows between the drain and the source of the semiconductor switch 14. The current value substantially coincides with the current value flowing between the drain and source of the semiconductor switch 15. Further, the on-resistance of the semiconductor switch 14 is substantially the same as the on-resistance of the semiconductor switch 15. For this reason, the energy consumed by the on-resistance of the semiconductor switch 14 is substantially the same as the energy consumed by the on-resistance of the semiconductor switch 15, so that the temperature of the semiconductor switch 14 substantially matches the temperature of the semiconductor switch 15. Yes. Therefore, detecting the temperature of the semiconductor switch 14 corresponds to detecting the temperature of the semiconductor switch 15, and the temperature sensor 17 corresponds to a temperature sensor detecting the temperature of the semiconductor switch 15.
　制御装置１８には、半導体スイッチ１４，１５のオンを指示するオン信号と、半導体スイッチ１４，１５のオフを指示するオフ信号とが入力される。
　制御装置１８は、オン信号が入力された場合、前述したように、半導体スイッチ１４，１５夫々のゲートに向けて一定の電圧を出力することによって、半導体スイッチ１４，１５をオンにする。 The control device 18 receives an ON signal for instructing to turn on the semiconductor switches 14 and 15 and an OFF signal for instructing to turn off the semiconductor switches 14 and 15.
When the ON signal is input, the control device 18 outputs the constant voltage toward the gates of the semiconductor switches 14 and 15 as described above, thereby turning on the semiconductor switches 14 and 15.
　制御装置１８は、オフ信号が入力された場合、前述したように、寄生容量Ｐ１４，Ｐ１５に放電を行わせることによって、半導体スイッチ１４，１５をオフにする。このとき、制御装置１８は、電流センサ１６から取得した電流情報が示す電流値と、温度センサ１７から取得した温度情報が示す温度とに基づいて、寄生容量Ｐ１４，Ｐ１５夫々が電荷を放出する速度、即ち、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値が低下する速度を調整する。 When the off signal is input, the control device 18 turns off the semiconductor switches 14 and 15 by causing the parasitic capacitors P14 and P15 to discharge as described above. At this time, the controller 18 speeds the parasitic capacitances P14 and P15 to release charges based on the current value indicated by the current information acquired from the current sensor 16 and the temperature indicated by the temperature information acquired from the temperature sensor 17. That is, the speed at which the voltage value across the parasitic capacitances P14 and P15 decreases is adjusted.
　図２は制御装置１８の回路図である。制御装置１８は、オン用スイッチ２０，２１、低速オフ用スイッチ２２、高速オフ用スイッチ２３、低速用回路２４、高速用回路２５、制御部２６、ダイオードＤ１，Ｄ２及び抵抗Ｒ２，Ｒ３，・・・，Ｒ１０を有する。制御部２６は、入力端２６ａ，２６ｂ，２６ｃ及び出力端２６ｄ，２６ｅ，２６ｆを有する。 FIG. 2 is a circuit diagram of the control device 18. The control device 18 includes on switches 20 and 21, a low speed off switch 22, a high speed off switch 23, a low speed circuit 24, a high speed circuit 25, a control unit 26, diodes D1 and D2, and resistors R2, R3,. ., Having R10 The control unit 26 has input terminals 26a, 26b, and 26c and output terminals 26d, 26e, and 26f.
　オン用スイッチ２０，２１夫々は、半導体スイッチ１４，１５をオンにするためスイッチである。低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々は半導体スイッチ１４，１５をオフにするためのスイッチである。オン用スイッチ２０は、ＰＮＰ型のバイポーラトランジスタである。オン用スイッチ２１、低速オフ用スイッチ２２及び高速オフ用スイッチ２３は、ＮＰＮ型のバイポーラトランジスタである。 The on switches 20 and 21 are switches for turning on the semiconductor switches 14 and 15, respectively. The low-speed off switch 22 and the high-speed off switch 23 are switches for turning off the semiconductor switches 14 and 15, respectively. The on switch 20 is a PNP-type bipolar transistor. The on switch 21, the low speed off switch 22, and the high speed off switch 23 are NPN-type bipolar transistors.
　オン用スイッチ２０のエミッタには所定の電圧Ｖｃが印加されている。オン用スイッチ２０のコレクタにはダイオードＤ１のアノードが接続されている。ダイオードＤ１のカソードにはダイオードＤ２のアノードが接続されている。ダイオードＤ２のカソードは、低速用回路２４及び高速用回路２５夫々の一端に接続されている。このように、オン用スイッチ２０のコレクタには、ダイオードＤ１，Ｄ２を介して、低速用回路２４及び高速用回路２５夫々の一端が接続されている。 A predetermined voltage Vc is applied to the emitter of the on switch 20. The anode of the diode D1 is connected to the collector of the on switch 20. The anode of the diode D2 is connected to the cathode of the diode D1. The cathode of the diode D2 is connected to one end of each of the low speed circuit 24 and the high speed circuit 25. Thus, one end of each of the low speed circuit 24 and the high speed circuit 25 is connected to the collector of the on switch 20 via the diodes D1 and D2.
　低速用回路２４の他端には低速オフ用スイッチ２２のコレクタが接続されている。高速用回路２５の他端には高速オフ用スイッチ２３のコレクタが接続されている。低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々のエミッタは接地されている。ダイオードＤ１のカソードは、更に、抵抗Ｒ２の一端に接続されている。抵抗Ｒ２の他端は半導体スイッチ１４，１５夫々のゲートに接続されている。このように、半導体スイッチ１４，１５夫々のゲートは、ダイオードＤ１及び抵抗Ｒ２を介して、オン用スイッチ２０のコレクタに接続されている。 The collector of the low speed off switch 22 is connected to the other end of the low speed circuit 24. The other end of the high speed circuit 25 is connected to the collector of the high speed off switch 23. The emitters of the low-speed off switch 22 and the high-speed off switch 23 are grounded. The cathode of the diode D1 is further connected to one end of the resistor R2. The other end of the resistor R2 is connected to the gates of the semiconductor switches 14 and 15, respectively. As described above, the gates of the semiconductor switches 14 and 15 are connected to the collector of the ON switch 20 via the diode D1 and the resistor R2.
　また、オン用スイッチ２０のエミッタには抵抗Ｒ３の一端が接続されている。オン用スイッチ２０のベースには、抵抗Ｒ３の他端と、抵抗Ｒ４の一端とが接続されている。抵抗Ｒ４の他端は、オン用スイッチ２１のコレクタに接続されている。オン用スイッチ２１のベースには抵抗Ｒ５，Ｒ６夫々の一端が接続されている。オン用スイッチ２１のエミッタと、抵抗Ｒ５の他端とは接地されている。抵抗Ｒ６の他端は、制御部２６の出力端２６ｄに接続されている。 Also, one end of a resistor R3 is connected to the emitter of the on switch 20. The other end of the resistor R3 and one end of the resistor R4 are connected to the base of the on switch 20. The other end of the resistor R4 is connected to the collector of the ON switch 21. One end of each of the resistors R5 and R6 is connected to the base of the on switch 21. The emitter of the on switch 21 and the other end of the resistor R5 are grounded. The other end of the resistor R6 is connected to the output end 26d of the control unit 26.
　低速オフ用スイッチ２２のベースには抵抗Ｒ７，Ｒ８夫々の一端が接続されている。低速オフ用スイッチ２２のエミッタと、抵抗Ｒ７の他端とは接地されている。抵抗Ｒ８の他端は制御部２６の出力端２６ｅに接続されている。
　高速オフ用スイッチ２３のベースには抵抗Ｒ９，Ｒ１０夫々の一端が接続されている。高速オフ用スイッチ２３のエミッタと、抵抗Ｒ９の他端とは接地されている。抵抗Ｒ１０の他端は制御部２６の出力端２６ｆに接続されている。
　電流センサ１６及び温度センサ１７夫々は制御部２６の入力端２６ａ，２６ｂに接続されている。制御部２６の入力端２６ｃにはオン信号及びオフ信号が入力される。 One end of each of resistors R7 and R8 is connected to the base of the low speed off switch 22. The emitter of the low speed off switch 22 and the other end of the resistor R7 are grounded. The other end of the resistor R8 is connected to the output end 26e of the control unit 26.
One end of each of the resistors R9 and R10 is connected to the base of the high-speed off switch 23. The emitter of the high-speed off switch 23 and the other end of the resistor R9 are grounded. The other end of the resistor R10 is connected to the output end 26f of the control unit 26.
The current sensor 16 and the temperature sensor 17 are connected to the input terminals 26a and 26b of the control unit 26, respectively. An ON signal and an OFF signal are input to the input terminal 26 c of the control unit 26.
　図３は低速用回路２４の回路図である。低速用回路２４は抵抗Ｒ１１を有する。抵抗Ｒ１１の一端は、ダイオードＤ１，Ｄ２を介してオン用スイッチ２０のコレクタに接続されている。抵抗Ｒ１１の他端は低速オフ用スイッチ２２のコレクタに接続されている。
　図４は高速用回路２５の回路図である。高速用回路２５は、コンデンサＣ１及び抵抗Ｒ１２を有する。コンデンサＣ１及び抵抗Ｒ１夫々の一端は、ダイオードＤ１，Ｄ２を介してオン用スイッチ２０のコレクタに接続されている。コンデンサＣ１及び抵抗Ｒ１２夫々の他端は高速オフ用スイッチ２３のコレクタに接続されている。
　高速用回路２５のインピーダンスの絶対値は、低速用回路２４のインピーダンスの絶対値よりも小さい。 FIG. 3 is a circuit diagram of the low speed circuit 24. The low speed circuit 24 has a resistor R11. One end of the resistor R11 is connected to the collector of the ON switch 20 via diodes D1 and D2. The other end of the resistor R11 is connected to the collector of the low-speed off switch 22.
FIG. 4 is a circuit diagram of the high speed circuit 25. The high speed circuit 25 has a capacitor C1 and a resistor R12. One end of each of the capacitor C1 and the resistor R1 is connected to the collector of the ON switch 20 via diodes D1 and D2. The other end of each of the capacitor C1 and the resistor R12 is connected to the collector of the high-speed off switch 23.
The absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24.
　オン用スイッチ２０、低速オフ用スイッチ２２、高速オフ用スイッチ２３、低速用回路２４及び高速用回路２５夫々は、第１スイッチ、第１回路側スイッチ、第２回路側スイッチ、第１回路及び第２回路として機能する。オン用スイッチ２０のエミッタ及びコレクタ夫々は、第１スイッチの一端及び他端に相当する。低速オフ用スイッチ２２のコレクタ及びエミッタは、第１回路側スイッチの一端及び他端に相当する。高速オフ用スイッチ２３のコレクタ及びエミッタは、第２回路側スイッチの一端及び他端に相当する。 The on switch 20, the low speed off switch 22, the high speed off switch 23, the low speed circuit 24 and the high speed circuit 25 are respectively a first switch, a first circuit side switch, a second circuit side switch, a first circuit and a first circuit. Functions as two circuits. The emitter and collector of the on switch 20 correspond to one end and the other end of the first switch, respectively. The collector and emitter of the low-speed off switch 22 correspond to one end and the other end of the first circuit side switch. The collector and emitter of the high-speed off switch 23 correspond to one end and the other end of the second circuit side switch.
　オン用スイッチ２０については、エミッタの電位を基準としたベースの電圧値が第１基準電圧値未満である場合、エミッタ及びコレクタ間に電流が流れることが可能となる。このとき、オン用スイッチ２０はオンである。第１基準電圧値は負の電圧値である。また、オン用スイッチ２０について、エミッタの電位を基準としたベースの電圧値が第１基準電圧値以上である場合、例えば、該ベースの電圧値がゼロＶである場合、エミッタ及びコレクタ間に電流が流れることはない。このときオン用スイッチ２０はオフである。 As for the ON switch 20, when the voltage value of the base with respect to the potential of the emitter is less than the first reference voltage value, a current can flow between the emitter and the collector. At this time, the on switch 20 is on. The first reference voltage value is a negative voltage value. In the ON switch 20, when the base voltage value with respect to the emitter potential is equal to or higher than the first reference voltage value, for example, when the base voltage value is zero V, a current flows between the emitter and the collector. Will not flow. At this time, the on switch 20 is off.
　オン用スイッチ２１、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々については、エミッタの電位を基準としたベースの電圧値が第２基準電圧値以上である場合、エミッタ及びコレクタ間に電流が流れることが可能となる。このとき、オン用スイッチ２１、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々はオンである。第２基準電圧値は正の電圧値である。また、オン用スイッチ２１、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々について、エミッタの電位を基準としたベースの電圧値が第２基準電圧値未満である場合、例えば、該ベースの電圧値がゼロＶである場合、エミッタ及びコレクタ間に電流が流れることはない。このとき、オン用スイッチ２１、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々はオフである。 For each of the on switch 21, the low speed off switch 22, and the high speed off switch 23, a current flows between the emitter and the collector when the voltage value of the base with respect to the potential of the emitter is equal to or higher than the second reference voltage value. It becomes possible. At this time, each of the on switch 21, the low speed off switch 22, and the high speed off switch 23 is on. The second reference voltage value is a positive voltage value. When the base voltage value with respect to the emitter potential is less than the second reference voltage value for each of the on switch 21, the low speed off switch 22, and the high speed off switch 23, for example, the base voltage value Is zero V, no current flows between the emitter and collector. At this time, each of the on switch 21, the low speed off switch 22, and the high speed off switch 23 is off.
　制御部２６は所謂マイクロコンピュータである。制御部２６は、出力端２６ｄ，２６ｅ，２６ｆ夫々からハイレベル電圧及びローレベル電圧を出力する。ハイレベル電圧の電圧値はローレベル電圧の電圧値よりも高く、ローレベル電圧の電圧値は略ゼロＶである。 The control unit 26 is a so-called microcomputer. The control unit 26 outputs a high level voltage and a low level voltage from the output terminals 26d, 26e, and 26f, respectively. The voltage value of the high level voltage is higher than the voltage value of the low level voltage, and the voltage value of the low level voltage is substantially zero V.
　制御部２６は、半導体スイッチ１４，１５をオンにする場合、出力端２６ｄ，２６ｅ，２６ｆ夫々からハイレベル電圧、ローレベル電圧及びローレベル電圧を出力する。 When the semiconductor switch 14 or 15 is turned on, the control unit 26 outputs a high level voltage, a low level voltage, and a low level voltage from the output terminals 26d, 26e, and 26f, respectively.
　出力端２６ｄからハイレベル電圧が出力された場合、出力端２６ｄから、電流が抵抗Ｒ６，Ｒ５の順に流れ、抵抗Ｒ５で電圧降下が生じる。このとき、オン用スイッチ２１において、エミッタの電位を基準としたベースの電圧値が第２基準電圧値以上となり、オン用スイッチ２１がオンとなる。オン用スイッチ２１がオンとなった場合、電圧Ｖｃが印加されている抵抗Ｒ３の一端から、電流が、抵抗Ｒ３，Ｒ４及びオン用スイッチ２１の順に流れ、抵抗Ｒ３で電圧降下が生じる。このとき、オン用スイッチ２０において、エミッタの電位を基準としたベースの電圧値が第１基準電圧値未満となり、オン用スイッチ２０がオンとなる。
　以上のことから、出力端２６ｄからハイレベル電圧が出力された場合、オン用スイッチ２０がオンとなる。 When a high level voltage is output from the output terminal 26d, a current flows from the output terminal 26d in the order of the resistors R6 and R5, and a voltage drop occurs at the resistor R5. At this time, in the on switch 21, the base voltage value based on the emitter potential is equal to or higher than the second reference voltage value, and the on switch 21 is turned on. When the on switch 21 is turned on, current flows from one end of the resistor R3 to which the voltage Vc is applied in the order of the resistors R3 and R4 and the on switch 21, and a voltage drop occurs in the resistor R3. At this time, in the on switch 20, the base voltage value based on the emitter potential is less than the first reference voltage value, and the on switch 20 is turned on.
From the above, when the high level voltage is output from the output terminal 26d, the ON switch 20 is turned ON.
　出力端２６ｅからローレベル電圧が出力された場合、抵抗Ｒ７，Ｒ８に電流が流れることはない。このとき、低速オフ用スイッチ２２において、エミッタを基準としたベースの電圧値は、略ゼロＶであり、第２基準電圧値未満である。結果、低速オフ用スイッチ２２はオフとなる。
　出力端２６ｆからローレベル電圧が出力された場合、抵抗Ｒ９，Ｒ１０に電流が流れることはない。このとき、高速オフ用スイッチ２３において、エミッタを基準としたベースの電圧値は、略ゼロＶであり、第２基準電圧値未満である。結果、高速オフ用スイッチ２３はオフとなる。 When a low level voltage is output from the output terminal 26e, no current flows through the resistors R7 and R8. At this time, in the low-speed off switch 22, the base voltage value with respect to the emitter is substantially zero V, which is less than the second reference voltage value. As a result, the low speed off switch 22 is turned off.
When a low level voltage is output from the output terminal 26f, no current flows through the resistors R9 and R10. At this time, in the high-speed off switch 23, the voltage value of the base with respect to the emitter is substantially zero V, which is less than the second reference voltage value. As a result, the high speed off switch 23 is turned off.
　オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々がオン、オフ及びオフである場合、電圧Ｖｃが印加されているオン用スイッチ２０のエミッタから、電流が２つの電流経路を介して流れる。２つの電流経路中の一方は、オン用スイッチ２０、ダイオードＤ１、抵抗Ｒ２、寄生容量Ｐ１４及び抵抗Ｒ１の順に電流が流れる電流経路である。２つの電流経路中の他方は、オン用スイッチ２０、ダイオードＤ１、抵抗Ｒ２、寄生容量Ｐ１５及び抵抗Ｒ１の順に電流が流れる電流経路である。 When the on switch 20, the low speed off switch 22 and the high speed off switch 23 are on, off and off, respectively, current flows from the emitter of the on switch 20 to which the voltage Vc is applied via two current paths. Flowing. One of the two current paths is a current path through which current flows in the order of the on switch 20, the diode D1, the resistor R2, the parasitic capacitance P14, and the resistor R1. The other of the two current paths is a current path through which current flows in the order of the on switch 20, the diode D1, the resistor R2, the parasitic capacitance P15, and the resistor R1.
　電流が２つの電流経路を流れることによって、寄生容量Ｐ１４，Ｐ１５夫々に電荷が蓄積され、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値が上昇する。半導体スイッチ１４，１５夫々について、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値が上昇した場合、ソースを基準としたゲートの電圧値が上昇し、ドレイン及びソース間の抵抗値が低下する。これにより、半導体スイッチ１４，１５夫々はオンとなる。 When the current flows through the two current paths, charges are accumulated in the parasitic capacitances P14 and P15, and the voltage value between both ends of the parasitic capacitances P14 and P15 increases. When the voltage value between both ends of the parasitic capacitances P14 and P15 is increased for each of the semiconductor switches 14 and 15, the gate voltage value with respect to the source is increased, and the resistance value between the drain and the source is decreased. As a result, the semiconductor switches 14 and 15 are turned on.
　制御部２６は、半導体スイッチ１４，１５をオフにする場合、出力端２６ｄからローレベル電圧を出力し、出力端２６ｅ，２６ｆの一方からハイレベル電圧を出力し、出力端２６ｅ，２６ｆの他方からローレベル電圧を出力する。 When the semiconductor switches 14 and 15 are turned off, the control unit 26 outputs a low level voltage from the output terminal 26d, outputs a high level voltage from one of the output terminals 26e and 26f, and outputs from the other of the output terminals 26e and 26f. Outputs low level voltage.
　出力端２６ｄからローレベル電圧が出力された場合、抵抗Ｒ５，Ｒ６に電流が流れることはない。このとき、オン用スイッチ２１において、エミッタを基準としたベースの電圧値は、略ゼロＶであり、第２基準電圧値未満である。結果、オン用スイッチ２１はオフとなる。オン用スイッチ２１がオフである場合、抵抗Ｒ３，Ｒ４に電流が流れることはない。このとき、オン用スイッチ２０において、エミッタを基準としたベースの電圧値は、略ゼロＶであり、第１基準電圧値以上である。結果、オン用スイッチ２０もオフとなる。
　以上のことから、出力端２６ｄからローレベル電圧が出力された場合、オン用スイッチ２０はオフとなる。 When a low level voltage is output from the output terminal 26d, no current flows through the resistors R5 and R6. At this time, in the ON switch 21, the voltage value of the base with respect to the emitter is substantially zero V, which is less than the second reference voltage value. As a result, the on switch 21 is turned off. When the on switch 21 is off, no current flows through the resistors R3 and R4. At this time, in the ON switch 20, the voltage value of the base with respect to the emitter is substantially zero V, which is equal to or higher than the first reference voltage value. As a result, the on switch 20 is also turned off.
From the above, when the low level voltage is output from the output terminal 26d, the on switch 20 is turned off.
　出力端２６ｅからハイレベル電圧が出力された場合、出力端２６ｅから、電流が抵抗Ｒ８，Ｒ７の順に流れ、抵抗Ｒ７で電圧降下が生じる。このとき、低速オフ用スイッチ２２において、エミッタの電位を基準としたベースの電圧値が第２基準電圧値以上となり、低速オフ用スイッチ２２がオンとなる。
　同様に、出力端２６ｆからハイレベル電圧が出力された場合、出力端２６ｆから、電流が抵抗Ｒ１０，Ｒ９の順に流れ、抵抗Ｒ９で電圧降下が生じる。このとき、高速オフ用スイッチ２３において、エミッタの電位を基準としたベースの電圧値が第２基準電圧値以上となり、高速オフ用スイッチ２３がオンとなる。 When a high-level voltage is output from the output terminal 26e, current flows from the output terminal 26e in the order of the resistors R8 and R7, and a voltage drop occurs at the resistor R7. At this time, in the low-speed off switch 22, the base voltage value based on the emitter potential becomes equal to or higher than the second reference voltage value, and the low-speed off switch 22 is turned on.
Similarly, when a high level voltage is output from the output terminal 26f, a current flows from the output terminal 26f in the order of the resistors R10 and R9, and a voltage drop occurs in the resistor R9. At this time, in the high-speed off switch 23, the base voltage value based on the emitter potential becomes equal to or higher than the second reference voltage value, and the high-speed off switch 23 is turned on.
　オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々がオフ、オン及びオフである場合、寄生容量Ｐ１４，Ｐ１５夫々は放電し、電流が寄生容量Ｐ１４，Ｐ１５夫々から抵抗Ｒ２、低速用回路２４及び低速オフ用スイッチ２２の順に流れる。これにより、寄生容量Ｐ１４，Ｐ１５に蓄積されている電荷が放出され、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値が低下し、半導体スイッチ１４，１５夫々のドレイン及びソース間の抵抗値が上昇する。結果、半導体スイッチ１４，１５がオフとなり、半導体スイッチ１４，１５夫々のソース及びドレイン間に流れる電流が遮断される。 When the on switch 20, the low speed off switch 22 and the high speed off switch 23 are off, on and off, respectively, the parasitic capacitances P14 and P15 are discharged, and the current is supplied from the parasitic capacitances P14 and P15 to the resistor R2. Circuit 24 and low-speed off switch 22 flow in this order. As a result, the charges accumulated in the parasitic capacitors P14 and P15 are released, the voltage value across the parasitic capacitors P14 and P15 decreases, and the resistance value between the drain and source of each of the semiconductor switches 14 and 15 increases. To do. As a result, the semiconductor switches 14 and 15 are turned off, and the current flowing between the source and drain of each of the semiconductor switches 14 and 15 is cut off.
　同様に、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々がオフ、オフ及びオンである場合、寄生容量Ｐ１４，Ｐ１５夫々は放電し、電流が寄生容量Ｐ１４，Ｐ１５夫々から抵抗Ｒ２、高速用回路２５及び高速オフ用スイッチ２３の順に流れる。これにより、寄生容量Ｐ１４，Ｐ１５に蓄積されている電荷が放出され、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値が低下し、半導体スイッチ１４，１５夫々のドレイン及びソース間の抵抗値が上昇する。結果、半導体スイッチ１４，１５がオフとなり、半導体スイッチ１４，１５夫々のソース及びドレイン間に流れる電流が遮断される。 Similarly, when the on switch 20, the low speed off switch 22 and the high speed off switch 23 are off, off and on, respectively, the parasitic capacitances P14 and P15 are discharged, and the current is resistance from the parasitic capacitances P14 and P15. R2, the high-speed circuit 25, and the high-speed off switch 23 flow in this order. As a result, the charges accumulated in the parasitic capacitors P14 and P15 are released, the voltage value across the parasitic capacitors P14 and P15 decreases, and the resistance value between the drain and source of each of the semiconductor switches 14 and 15 increases. To do. As a result, the semiconductor switches 14 and 15 are turned off, and the current flowing between the source and drain of each of the semiconductor switches 14 and 15 is cut off.
　図５は制御装置１８の動作の説明図である。図５には、半導体スイッチ１４について、低速オフ用スイッチ２２をオンにした場合におけるゲートの電圧値の推移と、高速オフ用スイッチ２３をオンにした場合におけるゲートの電圧値の推移とが示されている。低速オフ用スイッチ２２をオンにした場合、及び、高速オフ用スイッチ２３をオンにした場合夫々に関して、半導体スイッチ１５のゲートの電圧値は、半導体スイッチ１４のゲートの電圧値と同様に推移する。
　図５に示されるゲートの電圧値の推移夫々について、縦軸はゲートの電圧値であり、横軸は時間である。 FIG. 5 is an explanatory diagram of the operation of the control device 18. FIG. 5 shows the transition of the gate voltage value when the low-speed off switch 22 is turned on and the transition of the gate voltage value when the high-speed off switch 23 is turned on for the semiconductor switch 14. ing. When the low-speed off switch 22 is turned on and when the high-speed off switch 23 is turned on, the voltage value of the gate of the semiconductor switch 15 changes in the same manner as the voltage value of the gate of the semiconductor switch 14.
For each transition of the gate voltage value shown in FIG. 5, the vertical axis represents the gate voltage value, and the horizontal axis represents time.
　前述したように、高速用回路２５のインピーダンスの絶対値は、低速用回路２４のインピーダンスの絶対値よりも小さい。このため、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々がオン、オフ及びオフである状態、即ち、半導体スイッチ１４，１５がオンである状態から、オン用スイッチ２０及び低速オフ用スイッチ２２をオフ及びオンにした場合、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値の低下速度は遅い。結果、オン用スイッチ２０及び低速オフ用スイッチ２２をオフ及びオンにした場合、半導体スイッチ１４，１５がオンからオフとなる時間は長く、半導体スイッチ１４，１５から発生する電磁波に高周波数成分は含まれない。 As described above, the absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24. For this reason, the on switch 20 and the low speed off switch 22 and the high speed off switch 23 are turned on, off and off, that is, the semiconductor switches 14 and 15 are turned on. When the off switch 22 is turned off and on, the rate of decrease in the voltage value across the parasitic capacitances P14 and P15 is slow. As a result, when the on switch 20 and the low speed off switch 22 are turned off and on, it takes a long time for the semiconductor switches 14 and 15 to turn from on to off, and the electromagnetic waves generated from the semiconductor switches 14 and 15 contain high frequency components. I can't.
　半導体スイッチ１４，１５がオンである状態から、オン用スイッチ２０及び高速オフ用スイッチ２３をオフ及びオンにした場合、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値の低下速度は速い。結果、オン用スイッチ２０及び高速オフ用スイッチ２３をオフ及びオンにした場合、半導体スイッチ１４，１５がオンからオフとなる時間は短く、スイッチング損失は小さい。スイッチング損失が小さい程、半導体スイッチ１４，１５の温度の上昇幅は小さい。 When the on switch 20 and the high speed off switch 23 are turned off and on from the state in which the semiconductor switches 14 and 15 are on, the voltage value decreasing speed between both ends of the parasitic capacitors P14 and P15 is fast. As a result, when the on switch 20 and the high speed off switch 23 are turned off and on, the time during which the semiconductor switches 14 and 15 are turned off from on is short and the switching loss is small. The smaller the switching loss, the smaller the increase in temperature of the semiconductor switches 14 and 15.
　以上のことから、制御部２６は、半導体スイッチ１４，１５をオフにする場合に、低速オフ用スイッチ２２及び高速オフ用スイッチ２３の中から、オンにするスイッチを、後述するように適切に選択することによって、半導体スイッチ１４，１５の温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制することが可能となる。 From the above, when turning off the semiconductor switches 14 and 15, the control unit 26 appropriately selects the switch to be turned on from the low speed off switch 22 and the high speed off switch 23 as described later. By doing so, it is possible to suppress the frequency of generation of electromagnetic waves having high frequency components while maintaining the temperature of the semiconductor switches 14 and 15 within a predetermined range.
　なお、高速用回路２５は、図４に示すように、コンデンサＣ１及び抵抗Ｒ１２の並列回路である。半導体スイッチ１４，１５がオンである場合、低速用回路２４及び高速用回路２５に電流は流れることはなく、高速用回路２５のコンデンサＣ１に電荷は蓄積されていない。このため、オン用スイッチ２０及び高速オフ用スイッチ２３をオフ及びオンにした直後、寄生容量Ｐ１４，Ｐ１５からコンデンサＣ１へ大きな電流が流れて、寄生容量Ｐ１４，Ｐ１５夫々の両端間の電圧値は急速に低下する。このため、より短い時間で半導体スイッチ１４，１５はオンからオフとなる。 The high-speed circuit 25 is a parallel circuit of a capacitor C1 and a resistor R12 as shown in FIG. When the semiconductor switches 14 and 15 are on, no current flows through the low-speed circuit 24 and the high-speed circuit 25, and no charge is accumulated in the capacitor C <b> 1 of the high-speed circuit 25. Therefore, immediately after the on switch 20 and the high speed off switch 23 are turned off and on, a large current flows from the parasitic capacitances P14 and P15 to the capacitor C1, and the voltage value between both ends of the parasitic capacitances P14 and P15 is rapid. To drop. For this reason, the semiconductor switches 14 and 15 are turned from on to off in a shorter time.
　また、前述したように、半導体スイッチ１４，１５夫々について、ゲートの電圧値の上昇に応じて、ドレイン及びソース間の抵抗値は低下し、ドレイン及びソース間に流れる電流値は上昇する。このため、ドレイン及びソース間に流れる電流値はゲートの電圧値と同様に推移する。 Also, as described above, for each of the semiconductor switches 14 and 15, the resistance value between the drain and the source decreases and the value of the current flowing between the drain and the source increases as the gate voltage value increases. For this reason, the value of the current flowing between the drain and the source changes in the same manner as the voltage value of the gate.
　図２に示すように、制御部２６の入力端２６ａには電流センサ１６から電流情報が入力される。制御部２６の入力端２６ｂには温度センサ１７から温度情報が入力される。制御部２６の入力端２６ｃにはオン信号及びオフ信号が入力される。 2, current information is input from the current sensor 16 to the input terminal 26a of the control unit 26. Temperature information is input from the temperature sensor 17 to the input end 26 b of the control unit 26. An ON signal and an OFF signal are input to the input terminal 26 c of the control unit 26.
　制御部２６は、図示しないＣＰＵ(Central Processing Unit)を有し、図示しないメモリに記憶されている制御プログラムを実行することによって、半導体スイッチ１４，１５をオンにするオン処理と、半導体スイッチ１４，１５をオフにするオフ処理とを実行する。 The control unit 26 includes a CPU (Central Processing Unit) (not shown) and executes a control program stored in a memory (not shown) to turn on the semiconductor switches 14 and 15, and the semiconductor switch 14, And an off process for turning off 15.
　制御部２６は、入力端２６ｃにオン信号が入力された場合にオン処理を実行する。制御部２６は、出力端２６ｄ，２６ｅ，２６ｆ夫々からハイレベル電圧、ローレベル電圧及びローレベル電圧を出力する。これにより、前述したように、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３は、オン、オフ及びオフとなり、半導体スイッチ１４，１５はオンとなる。制御部２６は、出力端２６ｄ，２６ｅ，２６ｆ夫々からハイレベル電圧、ローレベル電圧及びローレベル電圧を出力した後、オン処理を終了する。 The control unit 26 performs an on process when an on signal is input to the input terminal 26c. The control unit 26 outputs a high level voltage, a low level voltage, and a low level voltage from the output terminals 26d, 26e, and 26f, respectively. As a result, as described above, the on switch 20, the low speed off switch 22 and the high speed off switch 23 are turned on, off and off, and the semiconductor switches 14 and 15 are turned on. The control unit 26 outputs the high level voltage, the low level voltage, and the low level voltage from the output terminals 26d, 26e, and 26f, respectively, and then ends the ON process.
　図６は制御部２６が実行するオフ処理の手順を示すフローチャートである。制御部２６は、入力端２６ｃにオフ信号が入力された場合にオフ処理を実行する。まず、制御部２６は、電流センサ１６から入力端２６ａに入力された電流情報を取得する（ステップＳ１）。制御部２６は電流情報取得部として機能する。
　次に、制御部２６は、ステップＳ１で取得した電流情報が示す電流値が電流閾値以上であるか否かを判定する（ステップＳ２）。電流閾値は、一定であり、前述したメモリに予め記憶されている。 FIG. 6 is a flowchart showing the procedure of the off process executed by the control unit 26. The control unit 26 performs an off process when an off signal is input to the input terminal 26c. First, the control unit 26 acquires current information input from the current sensor 16 to the input terminal 26a (step S1). The control unit 26 functions as a current information acquisition unit.
Next, the control part 26 determines whether the electric current value which the electric current information acquired by step S1 shows is more than a current threshold value (step S2). The current threshold is constant and is stored in advance in the memory described above.
　制御部２６は、電流値が電流閾値未満であると判定した場合（Ｓ２：ＮＯ）、温度センサ１７から入力端２６ｂに入力された温度情報を取得する（ステップＳ３）。制御部２６は温度情報取得部としても機能する。
　次に、制御部２６は、ステップＳ３で取得した温度情報が示す温度が温度閾値以上であるか否かを判定する（ステップＳ４）。温度閾値も、一定であり、前述したメモリに予め記憶されている。 When it is determined that the current value is less than the current threshold (S2: NO), the control unit 26 acquires temperature information input from the temperature sensor 17 to the input terminal 26b (step S3). The control unit 26 also functions as a temperature information acquisition unit.
Next, the control unit 26 determines whether or not the temperature indicated by the temperature information acquired in step S3 is equal to or higher than a temperature threshold (step S4). The temperature threshold is also constant and is stored in advance in the memory described above.
　半導体スイッチ１４のドレイン及びソース間に流れる電流値が大きい程、半導体スイッチ１４のオン抵抗で熱として消費されるエネルギーは大きく、半導体スイッチ１４の温度が高い。従って、温度情報が示す温度が高いことは、半導体スイッチ１４のドレイン及びソース間に流れる電流値が大きいことを意味する。前述したように、半導体スイッチ１４の温度は半導体スイッチ１５の温度と略一致しているので、温度情報が示す温度が高いことは、半導体スイッチ１５のドレイン及びソース間に流れる電流値が大きいことを意味する。
　制御部２６は、ステップＳ２，Ｓ４を実行することによって、半導体スイッチ１４，１５に大きな電流が流れていないか否かを二重に確認する。 As the current value flowing between the drain and source of the semiconductor switch 14 increases, the energy consumed as heat by the on-resistance of the semiconductor switch 14 increases and the temperature of the semiconductor switch 14 increases. Therefore, a high temperature indicated by the temperature information means that a current value flowing between the drain and the source of the semiconductor switch 14 is large. As described above, since the temperature of the semiconductor switch 14 substantially matches the temperature of the semiconductor switch 15, the high temperature indicated by the temperature information indicates that the current value flowing between the drain and source of the semiconductor switch 15 is large. means.
The control unit 26 double-checks whether or not a large current is flowing through the semiconductor switches 14 and 15 by executing steps S2 and S4.
　制御部２６は、温度が温度閾値未満であると判定した場合（Ｓ４：ＮＯ）、出力端２６ｄからローレベル電圧を出力することによって、オン用スイッチ２０をオフにする（ステップＳ５）。更に、制御部２６は、出力端２６ｅからハイレベル電圧を出力することによって、低速オフ用スイッチ２２をオンにし（ステップＳ６）、出力端２６ｆからローレベル電圧を出力することによって、高速オフ用スイッチ２３をオフにする（ステップＳ７）。制御部２６は、ステップＳ５～Ｓ７を実行することによって、半導体スイッチ１４，１５をオフにする。このとき、半導体スイッチ１４，１５がオンからオフとなる時間は長く、半導体スイッチ１４，１５から発生する電磁波に高周波の周波数成分が含まれない。 When it is determined that the temperature is lower than the temperature threshold (S4: NO), the control unit 26 outputs the low level voltage from the output terminal 26d, thereby turning off the on switch 20 (step S5). Further, the control unit 26 turns on the low speed off switch 22 by outputting a high level voltage from the output terminal 26e (step S6), and outputs a low level voltage from the output terminal 26f to thereby switch on the high speed off. 23 is turned off (step S7). The control unit 26 turns off the semiconductor switches 14 and 15 by executing steps S5 to S7. At this time, it takes a long time for the semiconductor switches 14 and 15 to be turned off, and the electromagnetic waves generated from the semiconductor switches 14 and 15 do not contain high frequency components.
　制御部２６は、電流値が電流閾値以上であると判定した場合（Ｓ２：ＹＥＳ）、又は、温度が温度閾値以上であると判定した場合（Ｓ４：ＹＥＳ）、出力端２６ｄからローレベル電圧を出力することによって、オン用スイッチ２０をオフにする（ステップＳ８）。更に、制御部２６は、出力端２６ｅからローレベル電圧を出力することによって、低速オフ用スイッチ２２をオフにし（ステップＳ９）、出力端２６ｆからハイレベル電圧を出力することによって、高速オフ用スイッチ２３をオンにする（ステップＳ１０）。制御部２６は、ステップＳ８～Ｓ１０を実行することによって、半導体スイッチ１４，１５をオフにする。このとき、半導体スイッチ１４，１５がオンからオフとなる時間は短く、スイッチング損失が小さい。制御部２６はスイッチ制御部としても機能する。 When it is determined that the current value is equal to or higher than the current threshold (S2: YES), or when the temperature is determined to be equal to or higher than the temperature threshold (S4: YES), the control unit 26 generates a low level voltage from the output terminal 26d. By outputting, the on switch 20 is turned off (step S8). Further, the control unit 26 outputs the low-level voltage from the output terminal 26e, thereby turning off the low-speed off switch 22 (Step S9), and outputs the high-level voltage from the output terminal 26f, thereby switching the high-speed off switch. 23 is turned on (step S10). The control unit 26 turns off the semiconductor switches 14 and 15 by executing steps S8 to S10. At this time, the time during which the semiconductor switches 14 and 15 are turned off from on is short, and the switching loss is small. The control unit 26 also functions as a switch control unit.
　以上のように、制御装置１８では、制御部２６は、電流センサ１６から取得した電流情報が示す電流値が電流閾値未満であり、かつ、温度センサ１７から取得した温度情報が示す温度値が温度閾値未満である場合、半導体スイッチ１４，１５に大きな電流が流れていないため、大きなスイッチング損失が発生しにくい。このため、制御部２６は、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３をオフ、オン及びオフにする。このとき、半導体スイッチ１４，１５は長い時間をかけてオンからオフとなるため、半導体スイッチ１４，１５から発生する電磁波に高周波数成分は含まれない。また、半導体スイッチ１４，１５のドレイン及びソース間に流れる電流値が小さいので、スイッチング損失も小さい。このため、半導体スイッチ１４，１５の温度が所定範囲内に維持される。 As described above, in the control device 18, the control unit 26 determines that the current value indicated by the current information acquired from the current sensor 16 is less than the current threshold and the temperature value indicated by the temperature information acquired from the temperature sensor 17 is the temperature. When it is less than the threshold value, a large current does not flow through the semiconductor switches 14 and 15, so that a large switching loss is unlikely to occur. Therefore, the control unit 26 turns off, on, and off the on switch 20, the low speed off switch 22, and the high speed off switch 23. At this time, since the semiconductor switches 14 and 15 are turned from off to off over a long time, high frequency components are not included in the electromagnetic waves generated from the semiconductor switches 14 and 15. In addition, since the current value flowing between the drain and source of the semiconductor switches 14 and 15 is small, the switching loss is also small. For this reason, the temperature of the semiconductor switches 14 and 15 is maintained within a predetermined range.
　また、制御部２６は、電流センサ１６から取得した電流情報が示す電流値が電流閾値以上であるか、又は、温度センサ１７から取得した温度情報が示す温度値が温度閾値以上である場合、半導体スイッチ１４，１５のドレイン及びソース間を流れる電流値は大きい。このため、制御部２６は、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３をオフ、オフ及びオンにする。このとき、半導体スイッチ１４，１５は素早くオンからオフとなるため、スイッチング損失は小さく、半導体スイッチ１４，１５の温度が所定範囲内に維持される。 In addition, when the current value indicated by the current information acquired from the current sensor 16 is equal to or higher than the current threshold value, or the temperature value indicated by the temperature information acquired from the temperature sensor 17 is equal to or higher than the temperature threshold value, the control unit 26 The value of current flowing between the drains and sources of the switches 14 and 15 is large. Therefore, the control unit 26 turns off, off, and on the on switch 20, the low speed off switch 22, and the high speed off switch 23. At this time, since the semiconductor switches 14 and 15 are quickly turned from on to off, the switching loss is small, and the temperature of the semiconductor switches 14 and 15 is maintained within a predetermined range.
　以上のように、制御部２６が低速オフ用スイッチ２２及び高速オフ用スイッチ２３の中からオンにするスイッチを適切に選択した場合、スイッチング損失は常に小さく、半導体スイッチ１４，１５夫々のドレイン及びソースを流れる電流値が大きいとき、短い時間で半導体スイッチ１４，１５がオンからオフとなるので、高周波数成分を有する電磁波が発生する。このため、半導体スイッチの温度が所定範囲内に維持され、高周波数成分を有する電磁波が発生する頻度は小さい。 As described above, when the control unit 26 appropriately selects the switch to be turned on from the low-speed off switch 22 and the high-speed off switch 23, the switching loss is always small, and the drain and source of each of the semiconductor switches 14 and 15 When the value of the current flowing through the semiconductor switch 14 is large, the semiconductor switches 14 and 15 are turned off from on in a short time, so that electromagnetic waves having a high frequency component are generated. For this reason, the temperature of the semiconductor switch is maintained within a predetermined range, and the frequency with which an electromagnetic wave having a high frequency component is generated is small.
　なお、電源システム１の構成は、第１バッテリ１０の出力電圧値が、第２バッテリ１１の出力電圧値よりも高い構成に限定されず、第１バッテリ１０及び第２バッテリ１１の出力電圧値の大小関係が経時的に変動する構成であってもよい。このように構成された電源システム１では、半導体スイッチ１４，１５がオンである場合において、第１バッテリ１０の出力電圧値が第２バッテリ１１の出力電圧値よりも高いとき、第１バッテリ１０は、第２バッテリ１１及び負荷１２，１３に電力を供給し、第２バッテリ１１は蓄電する。同様の場合において、第１バッテリ１０の出力電圧値が第２バッテリ１１の出力電圧値よりも低いとき、第２バッテリ１１は、第１バッテリ１０及び負荷１２，１３に電力を供給し、第１バッテリ１０は蓄電する。同様の場合において、第１バッテリ１０及び第２バッテリ１１の出力電圧値が同じであるとき、第１バッテリ１０及び第２バッテリ１１は負荷１２，１３に電力を供給する。負荷１２，１３夫々は、第１バッテリ１０又は第２バッテリ１１から供給された電力を用いて作動する。 The configuration of the power supply system 1 is not limited to a configuration in which the output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11, and the output voltage values of the first battery 10 and the second battery 11 A configuration in which the magnitude relationship varies with time may be employed. In the power supply system 1 configured as described above, when the semiconductor switches 14 and 15 are on, when the output voltage value of the first battery 10 is higher than the output voltage value of the second battery 11, the first battery 10 Electric power is supplied to the second battery 11 and the loads 12 and 13, and the second battery 11 stores electricity. In the same case, when the output voltage value of the first battery 10 is lower than the output voltage value of the second battery 11, the second battery 11 supplies power to the first battery 10 and the loads 12, 13, and the first battery 10 The battery 10 stores electricity. In the same case, when the output voltage values of the first battery 10 and the second battery 11 are the same, the first battery 10 and the second battery 11 supply power to the loads 12 and 13. Each of the loads 12 and 13 operates using electric power supplied from the first battery 10 or the second battery 11.
　第１バッテリ１０及び第２バッテリ１１の出力電圧値の大小関係が経時的に変動するように、電源システム１が構成されている場合、制御部２６は、オフ処理のステップＳ２において、ステップＳ１で取得した電流情報が示す電流値の絶対値が電流閾値以上であるか否かを判定する。制御部２６は、電流値の絶対値が電流閾値未満であると判定した場合、ステップＳ３を実行し、電流値の絶対値が電流閾値以上であると判定した場合、ステップＳ８を実行する。 When the power supply system 1 is configured so that the magnitude relationship between the output voltage values of the first battery 10 and the second battery 11 varies with time, the control unit 26 performs step S1 in step S1 of the off process. It is determined whether or not the absolute value of the current value indicated by the acquired current information is greater than or equal to the current threshold value. When it is determined that the absolute value of the current value is less than the current threshold value, the control unit 26 executes step S3, and when it is determined that the absolute value of the current value is equal to or greater than the current threshold value, the control unit 26 executes step S8.
（実施の形態２）
　実施の形態１では、寄生ダイオードを通じて第１バッテリ１０及び第２バッテリ１１間に電流が流れることを防止するために、２つの半導体スイッチ１４，１５が用いられ、半導体スイッチ１４，１５夫々のソースは互いに接続されている。しかしながら、制御装置１８がオン又はオフにする半導体スイッチの数は２つに限定されない。例えば、バッテリの数が１つである電源システムでは、制御装置１８がオン又はオフにする半導体スイッチの数は１つであってもよい。 (Embodiment 2)
In the first embodiment, two semiconductor switches 14 and 15 are used to prevent a current from flowing between the first battery 10 and the second battery 11 through the parasitic diode, and the sources of the semiconductor switches 14 and 15 are respectively Are connected to each other. However, the number of semiconductor switches that the control device 18 turns on or off is not limited to two. For example, in a power supply system having one battery, the number of semiconductor switches that the control device 18 turns on or off may be one.
　以下では、実施の形態２について実施の形態１と異なる点を説明する。後述する構成を除く他の構成については実施の形態１と同様であるため、同様の符号を付してその詳細な説明を省略する。 Hereinafter, differences of the second embodiment from the first embodiment will be described. Since the other configuration except the configuration to be described later is the same as that of the first embodiment, the same reference numerals are given and detailed description thereof is omitted.
　図７は、実施の形態２における電源システム３の回路図である。電源システム３も、実施の形態１における電源システム１と同様に、車両に好適に搭載されている。電源システム３は、電源システム１と同様に、第１バッテリ１０、負荷１３、半導体スイッチ１４、電流センサ１６、温度センサ１７、制御装置１８及び抵抗Ｒ１を備える。寄生容量Ｐ１４は半導体スイッチ１４のゲート及びソース間に形成されている。 FIG. 7 is a circuit diagram of the power supply system 3 in the second embodiment. The power supply system 3 is also suitably mounted on the vehicle, like the power supply system 1 in the first embodiment. Similar to the power supply system 1, the power supply system 3 includes a first battery 10, a load 13, a semiconductor switch 14, a current sensor 16, a temperature sensor 17, a control device 18, and a resistor R <b> 1. The parasitic capacitance P14 is formed between the gate and the source of the semiconductor switch 14.
　第１バッテリ１０、半導体スイッチ１４、電流センサ１６、温度センサ１７、制御装置１８及び抵抗Ｒ１は、実施の形態１と同様に接続されている。半導体スイッチ１４のソースには、抵抗Ｒ１の一端の他に、負荷１３の一端が接続されている。負荷１３の他端は接地されている。 The first battery 10, the semiconductor switch 14, the current sensor 16, the temperature sensor 17, the control device 18, and the resistor R1 are connected in the same manner as in the first embodiment. In addition to one end of the resistor R1, one end of the load 13 is connected to the source of the semiconductor switch 14. The other end of the load 13 is grounded.
　制御装置１８は、半導体スイッチ１４のオン及びオフを実施の形態１と同様に行う。第１バッテリ１０は、半導体スイッチ１４がオンである場合、負荷１３に電力を供給する。半導体スイッチ１４がオフである場合、第１バッテリ１０は負荷１３に電力を供給することはなく、負荷１３への電力供給は停止する。負荷１３は、半導体スイッチ１４がオンである場合、第１バッテリ１０から供給された電力を用いて作動し、半導体スイッチ１４がオフである場合、電力が供給されないので、動作を停止する。 The control device 18 turns on and off the semiconductor switch 14 in the same manner as in the first embodiment. The first battery 10 supplies power to the load 13 when the semiconductor switch 14 is on. When the semiconductor switch 14 is off, the first battery 10 does not supply power to the load 13 and power supply to the load 13 is stopped. The load 13 operates using the electric power supplied from the first battery 10 when the semiconductor switch 14 is on, and stops operating because the electric power is not supplied when the semiconductor switch 14 is off.
　図８は制御装置１８の回路図である。実施の形態２と同様に、抵抗Ｒ２の一端はダイオードＤ１のカソードに接続されており、抵抗Ｒ２の他端は半導体スイッチ１４のゲートに接続されている。電流センサ１６は制御部２６の入力端２６ａに接続されている。温度センサ１７は制御部２６の入力端２６ｂに接続されている。制御部２６の入力端２６ｃにはオン信号及びオフ信号が入力される。 FIG. 8 is a circuit diagram of the control device 18. As in the second embodiment, one end of the resistor R2 is connected to the cathode of the diode D1, and the other end of the resistor R2 is connected to the gate of the semiconductor switch 14. The current sensor 16 is connected to the input terminal 26 a of the control unit 26. The temperature sensor 17 is connected to the input end 26 b of the control unit 26. An ON signal and an OFF signal are input to the input terminal 26 c of the control unit 26.
　制御部２６は、実施の形態１と同様にオン処理及びオフ処理を実行する。従って、制御部２６は、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３を、オン、オフ及びオフにすることによって、半導体スイッチ１４をオンにする。
　また、制御部２６は、半導体スイッチ１４のドレイン及びゲート間に流れる電流値が電流閾値未満であり、かつ、半導体スイッチ１４の温度が温度閾値未満であると判定した場合に、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々をオフ、オン及びオフにし、半導体スイッチ１４をオフにする。これにより、半導体スイッチ１４は長い時間をかけてオンからオフとなり、半導体スイッチ１４から発生する電磁波に高周波数成分が含まれることはない。 The control unit 26 performs an on process and an off process as in the first embodiment. Therefore, the control unit 26 turns on the semiconductor switch 14 by turning on, off, and turning off the on switch 20, the low speed off switch 22, and the high speed off switch 23.
Further, when the control unit 26 determines that the value of the current flowing between the drain and gate of the semiconductor switch 14 is less than the current threshold value and the temperature of the semiconductor switch 14 is less than the temperature threshold value, The low-speed off switch 22 and the high-speed off switch 23 are turned off, on, and off, respectively, and the semiconductor switch 14 is turned off. As a result, the semiconductor switch 14 is turned from on to off over a long time, and the electromagnetic wave generated from the semiconductor switch 14 does not contain a high frequency component.
　また、制御部２６は、半導体スイッチ１４のドレイン及びゲート間に流れる電流値が電流閾値以上であるか、又は、半導体スイッチ１４の温度が温度閾値以上であると判定した場合に、オン用スイッチ２０、低速オフ用スイッチ２２及び高速オフ用スイッチ２３夫々をオフ、オフ及びオンにし、半導体スイッチ１４をオフにする。これにより、半導体スイッチ１４は素早くオンからオフとなるため、スイッチング損失が小さく、半導体スイッチ１４の温度が所定範囲内に維持される。 In addition, the control unit 26 determines that the value of the current flowing between the drain and gate of the semiconductor switch 14 is equal to or higher than the current threshold value, or the temperature of the semiconductor switch 14 is equal to or higher than the temperature threshold value. The low-speed off switch 22 and the high-speed off switch 23 are turned off, off, and on, respectively, and the semiconductor switch 14 is turned off. Thereby, the semiconductor switch 14 is quickly turned from on to off, so that the switching loss is small and the temperature of the semiconductor switch 14 is maintained within a predetermined range.
　実施の形態２における制御装置１８の回路構成は実施の形態１と同様であり、前述したように、実施の形態２における制御部２６は実施の形態１と同様にオン処理及びオフ処理を行う。このため、実施の形態２における制御装置１８は、実施の形態１と同様の効果を奏する。 The circuit configuration of the control device 18 in the second embodiment is the same as that in the first embodiment, and as described above, the control unit 26 in the second embodiment performs an on process and an off process as in the first embodiment. For this reason, the control apparatus 18 in Embodiment 2 has the same effect as Embodiment 1. FIG.
　なお、実施の形態１，２において、低速用回路２４が有する構成部は抵抗Ｒ１１に限定されず、高速用回路２５が有する構成部もコンデンサＣ１及び抵抗Ｒ１２の並列回路に限定されない。高速用回路２５のインピーダンスの絶対値が低速用回路２４のインピーダンスの絶対値よりも小さければよい。ただし、低速用回路２４及び高速用回路２５夫々は、コンデンサ及び抵抗の少なくとも一方を有する。 In the first and second embodiments, the constituent part of the low-speed circuit 24 is not limited to the resistor R11, and the constituent part of the high-speed circuit 25 is not limited to the parallel circuit of the capacitor C1 and the resistor R12. It is only necessary that the absolute value of the impedance of the high speed circuit 25 is smaller than the absolute value of the impedance of the low speed circuit 24. However, each of the low-speed circuit 24 and the high-speed circuit 25 has at least one of a capacitor and a resistor.
　また、実施の形態１，２におけるオフ処理において、制御装置１８の制御部２６は、電流値（絶対値）が電流閾値以上であるか否かの電流判定、及び、温度が温度閾値以上であるか否かの温度判定の一方のみを行ってもよい。制御部２６が電流判定のみを行う場合、オフ処理において、制御部２６は、電流値（絶対値）が電流閾値未満であると判定した場合（Ｓ２：ＮＯ）、ステップＳ５を実行する。また、制御部２６が温度判定のみを行う場合、オフ処理において、制御部２６は、ステップＳ１，Ｓ２を実行することなく、ステップＳ３から処理を開始する。以上のように制御部２６がオフ処理を行った場合であっても、半導体スイッチの温度を所定範囲内に維持しながら、高周波数成分を有する電磁波が発生する頻度を抑制することができる。 In the off processing in the first and second embodiments, the control unit 26 of the control device 18 determines whether or not the current value (absolute value) is equal to or higher than the current threshold, and the temperature is equal to or higher than the temperature threshold. Only one of the temperature determinations may be performed. When the control unit 26 performs only current determination, in the off process, when the control unit 26 determines that the current value (absolute value) is less than the current threshold value (S2: NO), it executes Step S5. When the control unit 26 performs only the temperature determination, in the off process, the control unit 26 starts the process from step S3 without executing steps S1 and S2. As described above, even when the control unit 26 performs the off process, it is possible to suppress the frequency of generation of electromagnetic waves having high frequency components while maintaining the temperature of the semiconductor switch within a predetermined range.
　更に、半導体スイッチ１４，１５夫々は、ＦＥＴに限定されず、例えば、ＩＧＢＴ(Insulated Gate Bipolar Transistor)であってもよい。 Furthermore, the semiconductor switches 14 and 15 are not limited to FETs, but may be IGBTs (Insulated Gate Bipolar Transistors), for example.
　開示された実施の形態１，２は全ての点で例示であって、制限的なものではないと考えられるべきである。本発明の範囲は、上記した意味ではなく、請求の範囲によって示され、請求の範囲と均等の意味及び範囲内での全ての変更が含まれることが意図される。 The disclosed first and second embodiments are examples in all respects and should not be considered as restrictive. The scope of the present invention is defined not by the above meaning but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.
　１，３　制御装置
　１４，１５　半導体スイッチ
　２０　オン用スイッチ（第１スイッチ）
　２２　低速オフ用スイッチ（第１回路側スイッチ）
　２３　高速オフ用スイッチ（第２回路側スイッチ）
　２４　低速用回路（第１回路）
　２５　高速用回路（第２回路）
　２６　制御部（電流情報取得部、温度情報取得部、スイッチ制御部） 1,3 Control device 14,15 Semiconductor switch 20 ON switch (first switch)
22 Low speed off switch (1st circuit side switch)
23 High speed off switch (2nd circuit side switch)
24 Low speed circuit (first circuit)
25 High-speed circuit (second circuit)
26 Control unit (current information acquisition unit, temperature information acquisition unit, switch control unit)

Claims (3)

  1. 　第１端、第２端及び第３端を有し、前記第１端の電圧値の上昇に応じて、前記第２端及び第３端間の抵抗値が低下する半導体スイッチのオン及びオフを行う制御装置において、
    　一端に所定の電圧が印加され、他端に前記半導体スイッチの前記第１端が接続されている第１スイッチと、
    　該第１スイッチの他端に一端が接続されている第１回路と、
    　該第１回路の他端に一端が接続されている第１回路側スイッチと、
    　前記第１スイッチの他端に一端が接続され、インピーダンスの絶対値が前記第１回路のインピーダンスの絶対値よりも小さい第２回路と、
    　該第２回路の他端に一端が接続されている第２回路側スイッチと
    　を備えることを特徴とする制御装置。     A semiconductor switch having a first end, a second end, and a third end, wherein a resistance value between the second end and the third end decreases in accordance with an increase in voltage value of the first end. In the control device to perform,
    A first switch in which a predetermined voltage is applied to one end and the first end of the semiconductor switch is connected to the other end;
    A first circuit having one end connected to the other end of the first switch;
    A first circuit side switch having one end connected to the other end of the first circuit;
    A second circuit having one end connected to the other end of the first switch and having an absolute value of impedance smaller than the absolute value of the impedance of the first circuit;
    A second circuit side switch having one end connected to the other end of the second circuit.
  2. 　前記第２端及び第３端間を流れる電流値を示す電流情報を取得する電流情報取得部と、
    　前記電流情報取得部が取得した電流情報が示す電流値が電流閾値未満である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オン及びオフにし、
    　前記電流情報取得部が取得した電流情報が示す電流値が電流閾値以上である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オフ及びオンにするスイッチ制御部と
    　を備えることを特徴とする請求項１に記載の制御装置。     A current information acquisition unit that acquires current information indicating a current value flowing between the second end and the third end;
    When the current value indicated by the current information acquired by the current information acquisition unit is less than a current threshold, the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off,
    Switch control for turning off, off, and on each of the first switch, the first circuit side switch, and the second circuit side switch when the current value indicated by the current information acquired by the current information acquisition unit is greater than or equal to a current threshold value. The control device according to claim 1, further comprising:
  3. 　前記半導体スイッチの温度を示す温度情報を取得する温度情報取得部と、
    　前記温度情報取得部が取得した温度情報が示す温度が温度閾値未満である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オン及びオフにし、
    　前記温度情報取得部が取得した温度情報が示す温度が温度閾値以上である場合に、前記第１スイッチ、第１回路側スイッチ及び第２回路側スイッチ夫々をオフ、オフ及びオンにするスイッチ制御部と
    　を備えることを特徴とする請求項１に記載の制御装置。     A temperature information acquisition unit for acquiring temperature information indicating the temperature of the semiconductor switch;
    When the temperature indicated by the temperature information acquired by the temperature information acquisition unit is less than a temperature threshold, the first switch, the first circuit side switch, and the second circuit side switch are turned off, on, and off,
    A switch control unit that turns off, off, and on each of the first switch, the first circuit side switch, and the second circuit side switch when the temperature indicated by the temperature information acquired by the temperature information acquisition unit is equal to or higher than a temperature threshold. The control device according to claim 1, further comprising:
PCT/JP2016/074382 2015-09-11 2016-08-22 Control device WO2017043297A1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111880068A (en) * 2019-05-02 2020-11-03 西门子股份公司 Circuit arrangement and method for controlling a power semiconductor switch

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06291631A (en) * 1993-03-31 1994-10-18 Hitachi Ltd Method and circuit for driving voltage driven element
JPH1032976A (en) * 1996-07-16 1998-02-03 Fuji Electric Co Ltd Drive circuit of self-quenching-type semiconductor device
JP2004096318A (en) * 2002-08-30 2004-03-25 Mitsubishi Electric Corp Semiconductor device for electric power
US20110157756A1 (en) * 2009-12-30 2011-06-30 Alberto Zanardi Semiconductor Device with Overcurrent Protection
JP2014200123A (en) * 2013-03-29 2014-10-23 三洋電機株式会社 On-vehicle power supply unit and vehicle having the same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06291631A (en) * 1993-03-31 1994-10-18 Hitachi Ltd Method and circuit for driving voltage driven element
JPH1032976A (en) * 1996-07-16 1998-02-03 Fuji Electric Co Ltd Drive circuit of self-quenching-type semiconductor device
JP2004096318A (en) * 2002-08-30 2004-03-25 Mitsubishi Electric Corp Semiconductor device for electric power
US20110157756A1 (en) * 2009-12-30 2011-06-30 Alberto Zanardi Semiconductor Device with Overcurrent Protection
JP2014200123A (en) * 2013-03-29 2014-10-23 三洋電機株式会社 On-vehicle power supply unit and vehicle having the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111880068A (en) * 2019-05-02 2020-11-03 西门子股份公司 Circuit arrangement and method for controlling a power semiconductor switch
CN111880068B (en) * 2019-05-02 2023-10-17 西门子股份公司 Circuit arrangement and method for controlling a power semiconductor switch

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