JP2014176164A - Onboard charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-board charger capable of reducing the size thereof by charging the on-vehicle battery by using a three-phase bridge circuit of a drive inverter.SOLUTION: An onboard charger 100 is mounted on a vehicle which runs in a manner that, after converting a DC power stored in an on-vehicle battery 170 into an AC power with a three-phase bridge circuit 108 on a drive inverter 150, the converted AC power is supplied to a drive motor 180. A primary coil 104 receives AC power supply from an external power source 160. A secondary coil 105 is electrically connected to the three-phase bridge circuit 108 and is electromagnetically coupled with the primary coil 104 to transform the voltage of the AC power supplied the primary coil 104 to thereby charge the on-vehicle battery 170 via the three-phase bridge circuit 108.

Description

  The present invention relates to an in-vehicle charging device mounted on a vehicle that converts DC power stored in an in-vehicle battery into AC power using a three-phase bridge circuit of a drive inverter and travels by receiving the supplied AC power.

  2. Description of the Related Art Conventionally, an in-vehicle charging apparatus that charges an in-vehicle battery mounted on a vehicle by connecting to an external power source is known (for example, Patent Document 1). The on-vehicle charging device disclosed in Patent Document 1 is switched at a frequency of 100 kHz to 140 kHz with a power factor improving circuit that improves the power factor by changing the input current to a sine wave similar to the input voltage of the AC power supply every half cycle. A switching circuit that generates a transformer pulse, and a rectifier circuit that transforms the transformer pulse with a transformer and smoothes the transformer pulse to supply a DC voltage of 200 V to 400 V to the in-vehicle battery.

JP 2010-151595 A

  However, in Patent Document 1, each of the power factor correction circuit, the switching circuit, and the rectifier circuit is a dedicated circuit for the in-vehicle charging device, and the in-vehicle charging device has a circuit configuration independent of other devices. There is a problem that there is a limit to downsizing.

  The objective of this invention is providing the vehicle-mounted charging device which can be reduced in size by charging a vehicle-mounted battery using the three-phase bridge circuit of a drive inverter.

  An in-vehicle charging apparatus according to the present invention converts a DC power stored in an in-vehicle battery into an AC power using a three-phase bridge circuit of a drive inverter, and supplies the converted AC power to a drive motor to travel a vehicle. An on-vehicle charging device that is mounted on a primary coil that receives AC power from an external power source, and is electrically connected to the three-phase bridge circuit and electromagnetically coupled to the primary coil to supply the primary coil And a secondary coil that transforms the voltage of the AC power to be charged and charges the in-vehicle battery via the three-phase bridge circuit.

  According to the present invention, the vehicle-mounted battery can be reduced in size by using the three-phase bridge circuit of the drive inverter.

The figure which shows the structure of the vehicle-mounted charging device and drive inverter which concern on Embodiment 1 of this invention. The figure which shows the voltage change and electric current change of the external power supply and primary coil in Embodiment 1 of this invention Timing chart showing in-vehicle battery charging method according to Embodiment 1 of the present invention The figure which shows the relationship between the ON period and charging current in the switch circuit which repeats ON and OFF of the vehicle-mounted charging device which concerns on Embodiment 1 of this invention alternately. The figure which shows the structure of the vehicle-mounted charging device and drive inverter which concern on Embodiment 2 of this invention. The figure which shows the voltage change and electric current change of the external power supply and primary coil in Embodiment 2 of this invention Timing chart showing in-vehicle battery charging method according to Embodiment 2 of the present invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
<Configuration of in-vehicle charger>
The configuration of in-vehicle charging apparatus 100 according to Embodiment 1 of the present invention will be described with reference to FIG.

  The in-vehicle charging device 100 includes a common mode (hereinafter referred to as “CM”) filter 101, a switch circuit 102, a switch circuit 103, a primary coil 104, a secondary coil 105, a relay 106, a relay 107, It mainly comprises a control unit 110, a demagnetization circuit 111, a relay 151, and a relay 152. The vehicle-mounted charging device 100 charges the vehicle-mounted battery 170 using the three-phase bridge circuit 108 and the smoothing capacitor 109 that are part of the drive inverter 150. The primary coil 104 and the secondary coil 105 constitute an insulating transformer.

  The CM filter 101 removes common mode noise included in AC power supplied from the external power supply 160.

  The switch circuit 102 is provided between the CM filter 101 and one end side of the primary coil 104. The switch circuit 102 opens and closes the connection between the external power supply 160 and one end of the primary coil 104 and the demagnetization circuit 111 according to the control of the control unit 110.

  The switch circuit 103 is provided between the CM filter 101 and the other end side of the primary coil 104. The switch circuit 103 opens and closes the connection between the external power source 160 and the other end of the primary coil 104 and the demagnetization circuit 111 according to the control of the control unit 110.

  The primary coil 104 receives a supply of AC power from the CM filter 101 via the switch circuit 102 and the switch circuit 103, generates a magnetic field, and is electromagnetically coupled to the secondary coil 105.

  The secondary coil 105 is electromagnetically coupled to the primary coil 104 and generates AC power having a predetermined voltage. The primary coil 104 and the secondary coil 105 are electromagnetically coupled to each other and convert the voltage of the AC power supplied from the external power source 160.

  The relay 106 opens (turns off) the connection between the one end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 152 when the drive motor 180 is driven (when the vehicle is running) according to the control of the control unit 110. ). The relay 106 closes (turns on) the connection between the one end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 152 when charging the in-vehicle battery 170 according to the control of the control unit 110.

  The relay 107 opens (turns OFF) the connection between the other end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 151 when the drive motor 180 is driven according to the control of the control unit 110. The relay 107 closes (turns on) the connection between the other end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 151 when charging the in-vehicle battery 170 in accordance with the control of the control unit 110.

  The control unit 110 controls the switching elements 211 to 216 of the switch circuit 102, the switch circuit 103, the relay 106, the relay 107, and the three-phase bridge circuit 108 based on a charge start instruction signal, a charge stop signal, or an ignition signal input from the outside. Open and close. The control unit 110 switches between the ON state and the OFF state of the FET 201 and the FET 202 of the demagnetization circuit 111 based on a charge start instruction signal, a charge stop signal, or an ignition signal input from the outside. The control unit 110 variably sets the ON period in the switch circuit 102 or the switch circuit 103 that switches between ON and OFF alternately so that the charging current detected by the current sensors 120 and 121 becomes a predetermined amount.

  The demagnetization circuit 111 returns the excitation current remaining in the primary coil 104 to the external power supply 160 after the connection between the external power supply 160 and the in-vehicle charging device 100 is opened (turned off) according to the control of the control unit 110.

  The relay 151 and the relay 152 are provided between the three-phase bridge circuit 108 and the drive motor 180. The relay 151 and the relay 152 turn on the connection between the three-phase bridge circuit 108 and the drive motor 180 when the drive motor 180 is driven, and the three-phase bridge circuit 108 when the vehicle battery 170 is charged, according to the control of the control unit 110. The connection with the drive motor 180 is turned off.

<Configuration of demagnetization circuit>
The configuration of the demagnetization circuit 111 according to the first embodiment of the present invention will be described with reference to FIG.

  The demagnetization circuit 111 includes an FET 201 and an FET 202.

  The FET 201 has a source connected to the source of the FET 202 and a drain connected to one end of the primary coil 104 and the switch circuit 102. The FET 201 is turned on or off according to the control of the control unit 110.

  The FET 202 has a source connected to the source of the FET 201, and a drain connected to the other end of the primary coil 104 and the switch circuit 103. The FET 202 is turned on or off according to the control of the control unit 110.

<Configuration of drive inverter>
The configuration of drive inverter 150 in Embodiment 1 of the present invention will be described with reference to FIG.

  The drive inverter 150 includes a three-phase bridge circuit 108, a smoothing capacitor 109, and current sensors 120, 121, and 122.

  The drive inverter 150 converts DC power stored in the in-vehicle battery 170 into AC power and supplies the AC power to a drive motor 180 that is a drive unit of the vehicle.

  The three-phase bridge circuit 108 rectifies the electric power stored in the in-vehicle battery 170 and supplies it to the drive motor 180. Details of the configuration of the three-phase bridge circuit 108 will be described later.

  The smoothing capacitor 109 smoothes the current when supplying the electric power stored in the in-vehicle battery 170 to the three-phase bridge circuit 108.

  The current sensors 120, 121, and 122 detect a drive current that flows between each phase of the three-phase bridge circuit 108 and the drive motor 180 when the drive motor 180 is driven. Current sensors 120 and 121 detect charging current supplied from the secondary coil 105 to the in-vehicle battery 170 via the three-phase bridge circuit 108 when the in-vehicle battery 170 is charged.

<Configuration of three-phase bridge circuit>
The configuration of the three-phase bridge circuit 108 according to Embodiment 1 of the present invention will be described with reference to FIG.

  The three-phase bridge circuit 108 is provided between the secondary coil 105 and the in-vehicle battery 170, and opens and closes the connection between the secondary coil 105 and the in-vehicle battery 170, and the switching elements 211 to 216, respectively. And freewheeling diodes 217 to 222 that are reversely connected to each other. The switching elements 211 to 216 open and close in cooperation with the switch circuit 102 and the switch circuit 103.

  The switching element 211 and the switching element 212 connect the low potential side (− side) and the high potential side (+ side) of the in-vehicle battery 170 and are connected in series to each other. The pair of switching elements 211 and 212 constitutes a third-phase switching element.

  The switching element 213 and the switching element 214 connect the low potential side and the high potential side of the in-vehicle battery 170 and are connected in series to each other. The pair of switching elements 213 and switching elements 214 constitute a second-phase switching element.

  The switching element 215 and the switching element 216 connect the low potential side and the high potential side of the in-vehicle battery 170 and are connected in series to each other. The pair of switching elements 215 and 216 constitutes a first-phase switching element.

  One end of the secondary coil 105 is connected between the switching element 213 and the switching element 214. The other end of the secondary coil 105 is connected between the switching element 215 and the switching element 216.

  The three-phase bridge circuit 108 opens and closes the switching elements 211 to 216 according to the control of the control unit 110 during the charging operation, and converts the AC power supplied from the secondary coil 105 into DC power to the in-vehicle battery 170. Accumulate. The three-phase bridge circuit 108 opens and closes the switching elements 211 to 216 according to the control of the control unit 110 during the driving operation of the driving motor 180 to convert the DC power stored in the in-vehicle battery 170 into AC power. This is supplied to the drive motor 180. The three-phase bridge circuit 108 is used for both a charging operation when charging the in-vehicle battery 170 using the external power source 160 and a driving operation for driving the drive motor 180 using the in-vehicle battery 170. That is, the three-phase bridge circuit 108 is shared by both the in-vehicle charging device 100 and the drive inverter 150.

<In-vehicle battery charging method>
A method for charging vehicle-mounted battery 170 in Embodiment 1 of the present invention will be described with reference to FIGS. In FIG. 2, in addition to the waveform of the AC voltage _V m, _{V p} and the excitation current _{i t,} also described waveforms of the switching circuit 102 and the switch circuit 103. Further, in FIG. 2, the timing of the waveform of the AC voltage _V m, _{V p} and the excitation current _{i t,} and corresponds to the timing of the waveform of the switch circuit 102 and the switch circuit 103.

First, the in-vehicle charging apparatus 100 causes a voltage change of V _m indicated by a solid line in FIG. 2 from the external power source 160 when the external power source 160 is connected to the connection portion E during the charging operation for charging the in-vehicle battery 170. Receive AC power.

  The control unit 110 of the in-vehicle charging apparatus 100 turns on the relay 106 and the relay 107 and turns off the relay 151 and the relay 152 from time t0 to time t1.

Further, as shown in FIG. 3, the control unit 110 switches the switch circuit 102 so as to repeat ON and OFF alternately at a constant frequency and turns on the switch circuit 103 at time t0 to time t1. As a result, as shown by a solid line in FIG. 2, the primary coil 104 is supplied with an AC voltage V _p having a higher frequency than the AC voltage V _m .

  Further, the control unit 110 turns on the FET 202 of the demagnetization circuit 111 and turns off the FET 201 from time t0 to time t1.

The primary coil 104, flows the switch circuit 102 is the excitation current _{i t} at is ON. Moreover, the exciting current _{i t} in the primary coil 104, when the switch circuit 102 is OFF, through the body diode of the FET202 the FET 201, flows to the external power source 160. Then, the flow of the excitation current i _t stops attenuated by the attenuation of the magnetic field of the primary coil 104. Incidentally, as shown in FIG. 2, the AC voltage _V m, and _{V p} and the excitation current _{i t,} there is no shift of phases. Further, in FIG. 2, the exciting current _{i t} is indicated by a broken line.

  Further, at time t0 to time t1, the control unit 110 turns on the switching element 215 and the switching element 214 and turns off the switching element 213 and the switching element 216 in synchronization with the timing of turning on the switch circuit 102. .

  Then, the control unit 110 turns off the switching element 215 and the switching element 214 immediately after turning on the switch circuit 102. Note that the control unit 110 turns off the switching element 211 and the switching element 212 at times t0 to t1.

  In the in-vehicle charging apparatus 100 and the drive inverter 150, the following current flows are generated by the above operation at time t0 to t1.

By switching circuit 102 alternately repeats the ON and OFF, the primary coil 104, flows direction S1 of the excitation current _{i t.} In addition, when the switching element 215 and the switching element 214 are turned ON in synchronization with the timing when the switch circuit 102 is turned ON, the secondary coil 105 electromagnetically coupled to the primary coil 104 has a higher voltage than the voltage of the in-vehicle battery 170. An induced electromotive force is generated, and an induced current is generated. The induced current flows in the S2 direction from the secondary coil 105 toward the relay 106, and returns to the secondary coil 105 via the switching element 214 and the switching element 215.

  Subsequently, immediately after the switching circuit 102 is turned on, the switching element 215 and the switching element 214 are turned off, so that the induced current of the secondary coil 105 flows from the secondary coil 105 in the S2 direction, and the switching element 213 and the switching element are switched. Since the element 214 is OFF, it flows through the free wheel diode 219 in the S3 direction. Furthermore, the current that flows in the S3 direction is supplied to the in-vehicle battery 170 from the S4 direction. That is, a charging current flows through the in-vehicle charging device 100 in the directions of S1 to S4.

In addition, at time t1 to time t2, the control unit 110 turns on the switch circuit 102 and switches the switch circuit 103 so as to repeat ON and OFF alternately. Thus, the primary coil 104, as shown in FIG. 2, an AC voltage Vp of higher frequency is supplied than the AC voltage V _m.

  Further, the control unit 110 turns on the FET 201 of the demagnetization circuit 111 and turns off the FET 202 from time t1 to time t2. At this time, as shown in FIGS. 2 and 3, the control unit 110 switches the switch circuit 103 so as to repeat ON and OFF alternately at a constant frequency.

The primary coil 104, flows the switch circuit 103 is the excitation current _{i t} at is ON. The exciting current of the primary coil 104 flows to the external power source 160 via the body diodes of the FET 201 and the FET 202 when the switch circuit 103 is OFF. Then, the flow of the excitation current i _t stops attenuated by the attenuation of the magnetic field of the primary coil.

  Further, at time t1 to time t2, the control unit 110 turns on the switching element 216 and the switching element 213 and turns off the switching element 215 and the switching element 214 in synchronization with the timing at which the switch circuit 103 is turned on. .

  The controller 110 turns off the switching element 216 and the switching element 213 immediately after turning on the switch circuit 102. In addition, the control part 110 turns OFF the switching element 211 and the switching element 212 in the time t1-t2.

  In the in-vehicle charging device 100 and the drive inverter 150, the following current flows are generated by the above operation at times t1 to t2.

By switching circuit 103 alternately repeats the ON and OFF, the primary coil 104, flows the R1 direction of the excitation current _{i t.} In addition, when the switching element 216 and the switching element 213 are turned ON in synchronization with the timing when the switch circuit 102 is turned ON, the secondary coil 105 electromagnetically coupled to the primary coil 104 has a higher voltage than the voltage of the in-vehicle battery 170. An induced electromotive force is generated, and an induced current is generated. The induced current flows in the R2 direction from the secondary coil 105 toward the relay 107, and returns to the secondary coil 105 via the switching element 213 and the switching element 216.

  Subsequently, immediately after the switching circuit 102 is turned on, the switching element 216 and the switching element 213 are turned off, whereby the induced current of the secondary coil 105 flows from the secondary coil 105 in the R2 direction, and the switching element 213 and the switching element 213 are switched. Since the element 216 is OFF, it flows through the free wheel diode 221 in the R3 direction. Further, the current flowing in the R3 direction is supplied to the in-vehicle battery 170 from the R4 direction. That is, a charging current flows through the in-vehicle charging device 100 in the directions of R1 to R4.

<Operation of in-vehicle charger and drive inverter>
Operations of in-vehicle charging device 100 and drive inverter 150 in Embodiment 1 of the present invention will be described with reference to FIGS.

  The drive inverter 150 performs the following operation when the in-vehicle charging apparatus 100 is not operating and when the drive motor 180 is driven.

  That is, the control unit 110 turns off the relay 106 and the relay 107 and turns on the relay 151 and the relay 152. The three-phase bridge circuit 108 converts the DC power stored in the in-vehicle battery 170 into AC power under the control of the control unit 110, and supplies the AC power to the drive motor 180 via the relay 151 and the relay 152.

  The drive inverter 150 performs the following operation when the in-vehicle charging apparatus 100 is not operating and when the drive motor 180 is driven.

  That is, the control unit 110 detects the driving current flowing in each phase of the driving motor 180 by the current sensor 120, the current sensor 121, and the current sensor 122, and the three-phase so that the driving current of each phase becomes a predetermined current value. The switching elements 211, 212, 213, 214, 215, and 216 of each phase of the bridge circuit 108 are controlled to be turned on and off to generate a predetermined driving torque in the driving motor 180.

  On the other hand, in-vehicle charging apparatus 100 performs the following operation when drive inverter 150 is not operating and when in-vehicle battery charging 170 is charged.

  That is, the control unit 110 detects the charging current S3 flowing between time t0 and time t1 and the charging current R3 flowing between time t1 and time t2 by the current sensor 121 and the current sensor 120, respectively. Then, the control unit 110 controls the ON period of the switch circuit 102 or the switch circuit 103 that alternately repeats ON and OFF so that a predetermined charging current amount is obtained.

<Charging current control method>
A method for controlling the amount of charging current in Embodiment 1 of the present invention will be described with reference to FIG.

  FIG. 4 is a diagram showing the ON time of the switch circuit 102 or the switch circuit 103 that repeats ON and OFF alternately and the operation of the excitation current it of the primary coil 104. In FIG. 4, excitation currents it0 and it1 of the primary coil 104 show waveforms when the control unit 110 sets the ON time of the switch circuit 102 to Pt0 and Pt1 (Pt0> Pt1), respectively. The excitation current it0 is the maximum current.

  As shown in FIG. 4, the control unit 110 arbitrarily sets the ON period of the switch circuits 102 and 103 to change the excitation current it flowing in the primary coil 104 and generate it in the secondary coil 105. Control the amount of charge current.

<Effect of Embodiment 1>
According to the present embodiment, the in-vehicle battery 170 is charged using the three-phase bridge circuit 108 and the smoothing capacitor 109 that are part of the drive inverter 150, so that the rectifier circuit of the conventional charging device can be eliminated. Therefore, the vehicle-mounted charging device 100 can be reduced in size.

  In addition, according to the present embodiment, since the switch circuit 102 and the switch circuit 103 are intermittently switched ON and OFF, the alternating current supplied from the external power source 160 to the primary coil 104 is determined from the frequency of the external power source. The frequency can be increased, and the insulation transformer can be reduced in size.

  In this embodiment, since the AC power supply is directly switched, the phase of the load current is not greatly shifted from the phase of the AC voltage supplied from the external power supply 160. Thereby, according to this Embodiment, since the power factor improvement circuit of the conventional charging device can be eliminated, the vehicle-mounted charging device 100 can be reduced in size.

  In the present embodiment, an insulating transformer is provided between connection portion E of in-vehicle charging apparatus 100 connected to external power source 160 and in-vehicle battery 170. Thereby, according to the present embodiment, even when the three-phase bridge circuit 108 fails, it is possible to prevent the high voltage of the in-vehicle battery 170 from being applied to the connection portion E with the external power source 160. , Can improve safety.

  In the present embodiment, the connection between the three-phase bridge circuit 108 and the drive motor 180 is turned off when the in-vehicle battery 170 is charged. Thereby, according to this Embodiment, it can prevent that the alternating current power supplied from the external power supply 160 is supplied to the drive motor 180, and can improve the charging efficiency of the vehicle-mounted battery 170. FIG.

In the present embodiment, the current sensors 120, 121, and 122 are commonly used for charging the in-vehicle battery 170 and for traveling when driving the drive motor 180. Thereby, according to this Embodiment, the vehicle-mounted charging device 100 can be reduced in size.

  In the present embodiment, the charging current amount can be arbitrarily set by varying the switching time for directly switching the AC power from the external power source 160 when charging the in-vehicle battery 170. Thereby, according to this Embodiment, according to charging current amount, the input from the external power supply 160 can be restrict | limited, and the charging efficiency of the vehicle-mounted charging device 100 can be improved.

  Further, according to the present embodiment, the amount of charging current can be controlled according to the state of charge of in-vehicle battery 170, and the safety of in-vehicle battery 170 can be ensured.

(Embodiment 2)
<Configuration of in-vehicle charger>
The configuration of in-vehicle charging device 400 according to Embodiment 2 of the present invention will be described with reference to FIG.

  The in-vehicle charging device 400 shown in FIG. 5 is different from the in-vehicle charging device 100 according to the first embodiment shown in FIG. 1 in that a switch circuit 401, a switch circuit 402, a primary coil 403, a secondary coil 404, A relay 405, a relay 406, a demagnetization circuit 407, and a relay 451 are added, and a control unit 408 is provided instead of the control unit 110. In FIG. 5, parts having the same configuration as in FIG.

  The in-vehicle charging device 400 includes a CM filter 101, a switch circuit 102, a switch circuit 103, a primary coil 104, a secondary coil 105, a relay 106, a relay 107, a demagnetization circuit 111, a relay 151, The relay 152, the switch circuit 401, the switch circuit 402, the primary coil 403, the secondary coil 404, the relay 405, the relay 406, the demagnetization circuit 407, the control unit 408, and the relay 451 are mainly used. It is configured. The vehicle-mounted charging device 400 charges the vehicle-mounted battery 170 using the three-phase bridge circuit 108 and the smoothing capacitor 109 that are part of the drive inverter 150. The primary coil 403 and the secondary coil 404 constitute an insulating transformer.

  The switch circuit 102 is provided between the CM filter 101 and one end side of the primary coil 104. The switch circuit 102 opens and closes the connection between the external power source 160 and one end of the primary coil 104 and the demagnetization circuit 111 according to the control of the control unit 408.

  The switch circuit 103 is provided between the CM filter 101 and the other end side of the primary coil 104. The switch circuit 103 opens and closes the connection between the external power source 160 and the other end of the primary coil 104 and the demagnetization circuit 111 according to the control of the control unit 408.

  The switch circuit 401 is provided between the CM filter 101 and one end side of the primary coil 403. The switch circuit 401 opens and closes the connection between the external power source 160 and one end side of the primary coil 403 and the demagnetization circuit 407 according to the control of the control unit 408.

  The switch circuit 402 is provided between the CM filter 101 and the other end side of the primary coil 403. The switch circuit 402 opens and closes the connection between the external power source 160 and the other end of the primary coil 403 and the demagnetization circuit 407 according to the control of the control unit 408.

  The primary coil 403 receives a supply of AC power from the CM filter 101 via the switch circuit 401 and the switch circuit 402, generates a magnetic field, and is electromagnetically coupled to the secondary coil 404.

  The secondary coil 404 is electromagnetically coupled to the primary coil 403 and generates AC power having a predetermined voltage. The primary coil 403 and the secondary coil 404 are electromagnetically coupled to each other and convert the voltage of AC power supplied from the external power source 160.

  The relay 106 opens (turns off) the connection between the one end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 152 when the drive motor 180 is driven according to the control of the control unit 408. The relay 106 closes (turns on) the connection between the one end of the secondary coil 105 and the three-phase bridge circuit 108 when charging the in-vehicle battery 170 according to the control of the control unit 408.

  The relay 107 opens (turns OFF) the connection between the other end of the secondary coil 105 and the three-phase bridge circuit 108 and the relay 151 when the drive motor 180 is driven according to the control of the control unit 408. The relay 107 closes (turns on) the connection between the other end of the secondary coil 105 and the three-phase bridge circuit 108 when charging the in-vehicle battery 170 in accordance with the control of the control unit 408.

  The relay 405 opens (turns off) the connection between the one end of the secondary coil 404 and the three-phase bridge circuit 108 and the relay 152 when the drive motor 180 is driven according to the control of the control unit 408. The relay 405 closes (turns on) the connection between one end of the secondary coil 404 and the three-phase bridge circuit 108 when charging the in-vehicle battery 170 in accordance with the control of the control unit 408.

  The relay 406 opens (turns OFF) the connection between the other end of the secondary coil 404 and the three-phase bridge circuit 108 and the relay 451 when the drive motor 180 is driven according to the control of the control unit 408. The relay 406 closes (turns on) the connection between the other end of the secondary coil 404 and the three-phase bridge circuit 108 when charging the in-vehicle battery 170 in accordance with the control of the control unit 408.

  The demagnetization circuit 111 returns the excitation current remaining in the primary coil 104 to the external power supply 160 after the connection between the external power supply 160 and the in-vehicle charging device 100 is opened (turned off) according to the control of the control unit 408.

  The demagnetization circuit 407 returns the excitation current remaining in the primary coil 403 to the external power supply 160 after the connection between the external power supply 160 and the in-vehicle charging device 400 is opened (turned off) according to the control of the control unit 408. The configuration of the demagnetization circuit 407 is the same as that of the demagnetization circuit 111 shown in FIG.

  Based on a charge start instruction signal, a charge stop signal, or an ignition signal input from the outside, the control unit 408 switches the switching elements 211 to 216 of the switch circuit 102, the switch circuit 103, the relay 106, the relay 107, and the three-phase bridge circuit 108, The switch circuit 401, the switch circuit 402, the relay 405, the relay 406, and the relay 451 are opened and closed. Based on a charge start instruction signal, a charge stop signal, or an ignition signal input from the outside, the control unit 408 determines whether the FET 201 and FET 202 of the demagnetization circuit 111 and the FET (not shown) of the demagnetization circuit 407 are in an ON state and an OFF state. Switch.

  The relay 151, the relay 152, and the relay 451 are provided between the three-phase bridge circuit 108 and the drive motor 180. Relay 151, relay 152, and relay 451 turn on the connection between three-phase bridge circuit 108 and drive motor 180 when the vehicle is running, and three-phase bridge circuit 108 when charging vehicle battery 170, according to the control of control unit 408. And the drive motor 180 are turned off.

<Configuration of three-phase bridge circuit>
The configuration of the three-phase bridge circuit 108 according to the second embodiment of the present invention will be described with reference to FIG.

  The three-phase bridge circuit 108 is provided between the secondary coil 105 and the secondary coil 404 and the in-vehicle battery 170. The three-phase bridge circuit 108 includes switching elements 211 to 216 that open and close the connection between the secondary coil 105 and the secondary coil 404 and the in-vehicle battery 170.

  In the charging operation, the three-phase bridge circuit 108 opens and closes the switching elements 211 to 216 according to the control of the control unit 408, and converts AC power supplied from the secondary coil 105 and the secondary coil 404 into DC power. To be stored in the in-vehicle battery 170. The three-phase bridge circuit 108 is used for both a charging operation when charging the in-vehicle battery 170 using the external power source 160 and a driving operation for driving the drive motor 180 using the in-vehicle battery 170. That is, the three-phase bridge circuit 108 is shared by both the in-vehicle charging device 400 and the drive inverter 150.

  Since the configuration other than the above in the three-phase bridge circuit 108 is the same as that in the first embodiment, the description thereof is omitted.

<In-vehicle battery charging method>
A method of charging in-vehicle battery 170 in Embodiment 2 of the present invention will be described with reference to FIGS. 6A shows the voltage change and current change of the external power supply 160 and the primary coil 104, and FIG. 6B shows the voltage change and current change of the external power supply 160 and the primary coil 403.

  In FIG. 5, the ON and OFF timings of the switch circuit 102, the switch circuit 103, the switching elements 215 and 216, the FET 201, and the FET 202 are the same as those in FIG. In FIG. 5, the operation of the demagnetization circuit 407 with respect to the switch circuit 401 and the switch circuit 402 is the same as the operation of the demagnetization circuit 111 with respect to the switch circuit 102 and the switch circuit 103, and thus description thereof is omitted. Moreover, in this Embodiment, since the electric current flow of S1-S4 and R1-R4 is the same as the said Embodiment 1, the description is abbreviate | omitted.

First, the in-vehicle charging device 400 causes the AC power to generate a voltage change indicated by V _m in FIG. 6 from the external power source 160 when the external power source 160 is connected to the connection portion E during the charging operation for charging the in-vehicle battery 170. Receive the supply.

  The control unit 408 of the in-vehicle charging apparatus 400 turns on the relay 106, the relay 107, the relay 405, and the relay 406 and turns off the relay 151, the relay 152, and the relay 451 at time t0 to t1.

Further, at time t0 to time t1, the control unit 408 switches the switch circuit 102 so as to repeat ON and OFF alternately as shown in FIG. 7, and turns on the switch circuit 103. Thus, the primary coil 104, as shown in FIG. 6, the AC voltage V _p of the frequency higher than the AC voltage V _m is supplied.

In addition, at time t0 to t1, the control unit 408 of the in-vehicle charging apparatus 400 switches the switch circuit 401 so as to repeat ON and OFF alternately as shown in FIG. As a result, the primary coil 403 is supplied with an AC voltage V _q having a frequency higher than the AC voltage V _{m as} shown in FIG. 6.

Further, the control unit 408 controls FETs (not shown) of the demagnetization circuit 111 and the demagnetization circuit 407 in the same manner as in the first embodiment at time t0 to time t1. Thus, the primary coil 104, excitation current _{i t3} flows, also in the primary coil 403, excitation current _{i t4} flows. The excitation currents i _t3 and i _t4 are alternating currents having a frequency at which the switch circuit 102 and the switch circuit 401 are repeatedly turned on and off.

The ON / OFF cycle of the switch circuit 102 and the switch circuit 401 has a phase difference of 180 degrees under the control of the control unit 408. Therefore, the excitation current _it3 and the excitation current _it4 have a phase difference of 180 degrees.

  Further, at time t0 to time t1, the control unit 408 turns on the switching element 214 and the switching element 211 and turns off the switching element 213 and the switching element 212 in synchronization with the timing of turning on the switch circuit 401. . Next, immediately after the switch circuit 401 is turned ON, the switching element 214 and the switching element 211 are turned OFF.

  In the in-vehicle charging device 400 and the drive inverter 150, the following current flows are generated by the above operation from time t0 to time t1.

When the switch circuit 401 alternately repeats ON and OFF, the exciting current _{it4 in the} T1 direction flows through the primary coil 403. In addition, by turning on the switching element 214 and the switching element 211 in synchronization with the timing when the switch circuit 401 is turned on, the secondary coil 404 electromagnetically coupled to the primary coil 403 has a higher voltage than the voltage of the in-vehicle battery 170. An induced electromotive force is generated, and an induced current is generated. The induced current flows in the T2 direction from the secondary coil 404 toward the relay 405, and returns to the secondary coil 404 via the switching element 211 and the switching element 214.

  Subsequently, immediately after the switch circuit 401 is turned on, the switching element 214 and the switching element 211 are turned off, whereby the induced current of the secondary coil 404 flows in the T2 direction, and the switching element 213 and the switching element 214 are turned off. Therefore, it flows through the free wheel diode 219 in the T3 direction. Further, the current flowing in the T3 direction is supplied to the in-vehicle battery 170 from the T4 direction. That is, the charging current flows through the in-vehicle charging device 100 in the direction of T1 to T4.

At time t1 to time t2, the control unit 408 turns on the switch circuit 401 and switches the switch circuit 402 so as to repeat ON and OFF alternately as shown in FIG. As a result, the primary coil 403 is supplied with an AC voltage V _q having a frequency higher than the AC voltage V _{m as} shown in FIG. 6.

  Further, at time t1 to time t2, the control unit 408 turns on the switching element 213 and the switching element 212 and turns off the switching element 214 and the switching element 211 in synchronization with the timing of turning on the switch circuit 402. . Next, immediately after the switch circuit 401 is turned ON, the switching element 213 and the switching element 212 are turned OFF.

  In the in-vehicle charging device 400 and the drive inverter 150, the following current flows are generated by the above operation from time t1 to time t2.

By switching circuit 402 alternately repeats the ON and OFF, the primary coil 403 flows exciting current _{i t4} of U1 direction. In addition, the switching element 213 and the switching element 212 are turned on in synchronization with the timing when the switch circuit 402 is turned on, so that the secondary coil 404 electromagnetically coupled to the primary coil 403 has a higher voltage than the voltage of the in-vehicle battery 170. An induced electromotive force is generated, and an induced current is generated. The induced current flows in the U2 direction from the secondary coil 404 toward the relay 406 and returns to the secondary coil 404 via the switching element 212 and the switching element 213.

  Subsequently, immediately after the switch circuit 402 is turned on, the switching element 213 and the switching element 212 are turned off, whereby the induced current of the secondary coil 404 flows in the U2 direction, and the switching element 212 and the switching element 213 are turned off. Therefore, it flows through the freewheeling diode 217 in the U3 direction. Furthermore, the current that flows in the U3 direction is supplied to the in-vehicle battery 170 from the U4 direction. That is, the charging current flows through the in-vehicle charging device 100 in the directions U1 to U4.

<Operation of in-vehicle charger and drive inverter>
Operations of in-vehicle charging device 400 and drive inverter 150 according to Embodiment 2 of the present invention will be described with reference to FIGS.

  The drive inverter 150 performs the following operation when the in-vehicle charging device 400 is not operating and when the drive motor 180 is driven.

  That is, the control unit 408 turns off the relay 106, the relay 107, the relay 405, and the relay 406, and turns on the relay 151, the relay 152, and the relay 451. The three-phase bridge circuit 108 converts the DC power stored in the in-vehicle battery 170 into AC power under the control of the control unit 408, and supplies the AC power to the drive motor 180 via the relay 151, the relay 152, and the relay 451. To do.

  The drive inverter 150 performs the following operation when the in-vehicle charging device 400 is not operating and when the drive motor 180 is driven.

  That is, the control unit 408 detects the driving current flowing in each phase of the driving motor 180 by the current sensor 120, the current sensor 121, and the current sensor 122, and the three-phase so that the driving current of each phase becomes a predetermined current value. The switching elements 211, 212, 213, 214, 215, and 216 of each phase of the bridge circuit 108 are controlled to be turned on and off to generate a predetermined driving torque in the driving motor 180.

  On the other hand, in-vehicle charging apparatus 400 performs the following operation when drive inverter 150 is not operating and when in-vehicle battery charging 170 is charged.

  That is, the control unit 408 converts the charging current S3 and the charging current T3 that flow between time t0 and time t1, and the charging current R3 and the charging current U3 that flow between time t1 and time t2 into the current sensor 121 and the current t3. The ON time of the switch circuit 102, the switch circuit 103, the switch circuit 401, or the switch circuit 402 is controlled so as to be detected alternately by the sensor 120 and the current sensor 122, and repeatedly ON and OFF so that a predetermined charge amount is obtained.

  In addition, since the control method of the charging current amount in this Embodiment is the same as FIG. 4, the description is abbreviate | omitted.

<Effect of Embodiment 2>
According to the present embodiment, in addition to the effects of the first embodiment, since a plurality of insulating transformers are provided in parallel, the charging current supplied to the in-vehicle battery can be increased compared to the first embodiment. This can shorten the charging time of the in-vehicle battery.

  Further, according to the present embodiment, the load current can be distributed by controlling the exciting currents of the primary coils 104 and 403 of the insulating transformers connected in parallel to each other so as to have a phase difference of 180 degrees. It is possible to improve the power factor.

<Modification common to all embodiments>
In Embodiment 1 and Embodiment 2 described above, the drive inverter supplies AC power to the drive motor, but AC power may be supplied to portions other than the drive motor that requires power.

  In the first and second embodiments, relays are used to connect and open the three-phase bridge circuit 108 and the drive motor 180, and to connect and open the three-phase bridge circuit 108 and the insulating transformer. The same effect can be obtained with a high-power semiconductor switch.

  The in-vehicle charging device according to the present invention is mounted on a vehicle that converts DC power stored in an in-vehicle battery into AC power using a three-phase bridge circuit of a drive inverter, and receives the supplied AC power to travel. It is suitable for.

DESCRIPTION OF SYMBOLS 100 Car-mounted charging device 101 CM filter 102, 103 Switch circuit 104 Primary coil 105 Secondary coil 106, 107, 151, 152 Relay 108 Three-phase bridge circuit 109 Smoothing capacitor 110 Control part 111 Demagnetization circuit 120,121,122 Current sensor 150 Drive inverter 160 External power supply 170 On-vehicle battery 180 Drive motor 201, 202 FET
211, 212, 213, 214, 215, 216 Switching element 217, 218, 219, 220, 221, 222 Free-wheeling diode

Claims (6)

A vehicle-mounted charging device mounted on a vehicle that converts DC power stored in a vehicle-mounted battery into AC power using a three-phase bridge circuit of a drive inverter and supplies the converted AC power to a drive motor. ,
A primary coil that receives AC power from an external power source;
Electrically connected to the three-phase bridge circuit and electromagnetically coupled to the primary coil, thereby transforming the voltage of AC power supplied to the primary coil and charging the vehicle battery via the three-phase bridge circuit A secondary coil to
A vehicle-mounted charging device. A switching unit that turns on the connection between the three-phase bridge circuit and the drive motor when the vehicle is running and turns off the connection between the three-phase bridge circuit and the drive motor when the vehicle battery is charged; ,
The in-vehicle charging device according to claim 1. A first switching unit that opens and closes a connection between the external power source and one end of the primary coil;
A second switching unit that opens and closes a connection between the external power source and the other end of the primary coil;
The first switching unit that turns on one of the first switching unit and the second switching unit and controls the other to alternately repeat ON and OFF, and repeats ON and OFF alternately. Alternatively, a control unit that synchronizes with the second switching unit and temporarily turns off the switching element connected to the secondary coil of the three-phase bridge circuit and the low-potential side of the in-vehicle battery, and
Further comprising
The secondary coil is
The switching control electromagnetically couples with the primary coil, generates an induced current when the switching element is temporarily turned on, and subsequently switches the switching of the three-phase bridge circuit when the switching element is turned off. Charging the in-vehicle battery via a free-wheeling diode reversely connected to an in-phase switching element paired with the element;
The in-vehicle charging device according to claim 1. A first switching unit that opens and closes a connection between the external power source and one end of the primary coil;
A second switching unit that opens and closes a connection between the external power source and the other end of the primary coil;
Either one of the first switching unit and the second switching unit is turned on, and the other one is switched to be alternately switched between ON and OFF, and the ON period in either one is set to be variable. A control unit;
Further comprising
The secondary coil is
Electromagnetically coupled with the primary coil by the switching control, and charging the in-vehicle battery with a charging current according to the ON period,
The in-vehicle charging device according to claim 1. The controller is
When the vehicle battery is charged, the ON period is set so that the charging current detected by the current sensor of the three-phase bridge circuit for detecting the driving current of the driving motor becomes a predetermined amount.
The in-vehicle charging device according to claim 4. An insulating transformer composed of the primary coil and the secondary coil is:
There are several,
Each of the insulating transformers
Connected in parallel between the external power source and the three-phase bridge circuit;
The in-vehicle charging device according to claim 1.

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