JP2010035279A - Power supply system and electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further enhance efficiency in a power supply system of an electric vehicle which can transfer power between and among AC power supplies outside a vehicle. <P>SOLUTION: There is provided an AC bus 10, and direct AC-AC conversion is performed by a matrix converter between and among motor generators 16-1, 16-2, an electric load 22, the system AC power supply 40 outside the vehicle, and the AC bus 10. Then, an inverter 14 is connected between the AC bus 10 and a power accumulation device 24, and a voltage of the AC bus 10 is adjusted by controlling the inverter 14 so that the voltage of the AC bus 10 should not be raised unnecessarily high. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power supply system and an electric vehicle, and more particularly, to a power supply system for a vehicle configured to be able to receive power from an AC power supply outside the vehicle and to supply power to the AC power supply, and an electric vehicle equipped with the power supply system. .

  Electric vehicles such as electric vehicles, hybrid vehicles, and fuel cell vehicles have attracted attention as environmentally friendly vehicles. These vehicles are equipped with an electric motor that generates a driving force for driving and a power storage device that stores electric power supplied to the electric motor. A hybrid vehicle is a vehicle equipped with an internal combustion engine as a power source together with an electric motor, and a fuel cell vehicle is a vehicle equipped with a fuel cell as a DC power source for driving the vehicle.

  In these vehicles, since driving power is generated by electric power, efficient power conversion becomes a problem. Japanese Patent Laying-Open No. 2006-25577 (Patent Document 1) discloses a hybrid vehicle equipped with a matrix converter capable of converting power with high efficiency. In this hybrid vehicle, the first and second AC rotating electric machines are connected to a matrix converter, and direct AC-AC conversion is performed between the first and second AC rotating electric machines by the matrix converter.

That is, in this hybrid vehicle, power conversion is performed directly and directly between the first and second AC rotating electric machines by the matrix converter without passing through the DC link portion. Therefore, according to this hybrid vehicle, a highly efficient vehicle with low power loss is realized (see Patent Document 1).
JP 2006-25577 A JP 2005-333783 A JP 2007-326449 A

  In recent years, so-called plug-in hybrid vehicles that can be charged from an AC power source (such as a system power source) outside the vehicle have also attracted much attention. In this plug-in hybrid vehicle, since the ratio of electric power to the energy source is higher than that of a normal hybrid vehicle, further expectation for higher efficiency is great.

  The hybrid vehicle disclosed in the above Japanese Patent Laid-Open No. 2006-25577 is useful because it is highly efficient in that power is directly converted between the first and second AC rotating electric machines using a matrix converter. In the above publication, charging from an AC power supply outside the vehicle is not considered.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to further increase the efficiency of a power supply system that can exchange power with an AC power supply outside the vehicle.

  Another object of the present invention is to further increase the efficiency of an electric vehicle that can exchange electric power with an AC power supply outside the vehicle.

  According to the present invention, the power supply system is a vehicle power supply system configured to be capable of executing at least one of power reception from an AC power supply outside the vehicle and power supply to the AC power supply outside the vehicle. A vehicle is equipped with a chargeable / dischargeable power storage device and an AC electric load that operates by receiving AC power. The power supply system includes an AC bus, first and second matrix converters, an inverter, and a control device. The AC bus energizes AC power. The first matrix converter is connected between the AC bus and the AC electrical load, and performs voltage conversion between the AC bus and the AC electrical load based on a given first control signal. The second matrix converter is connected to an AC bus, and receives a voltage from an AC power supply outside the vehicle or supplies power to the AC power supply, based on a second control signal applied to the voltage between the AC bus and the AC power supply. Perform the conversion. The inverter is connected between the AC bus and the power storage device, and performs voltage conversion between the AC bus and the power storage device based on a third control signal provided. The control device generates a first control signal based on the required power of the AC electric load, generates a second control signal based on a power command value indicating power to be exchanged with the AC power supply outside the vehicle, A third control signal is generated so as to adjust the voltage of the AC bus to a predetermined target voltage by the inverter.

  Preferably, the control device sets the target voltage based on the required voltage of the AC electric load and the voltage of the AC power supply.

  More preferably, the control device sets a higher one of the required voltage of the AC electric load and the voltage of the AC power supply outside the vehicle as the target voltage.

  According to the present invention, the electric vehicle is an electric vehicle capable of executing at least one of power reception from an AC power supply outside the vehicle and power supply to the AC power supply outside the vehicle, and a chargeable / dischargeable power storage device; An AC motor, an AC bus, first and second matrix converters, an inverter, and a control device are provided. The AC motor receives AC power and generates a driving force. The AC bus energizes AC power. The first matrix converter is connected between the AC bus and the AC motor, and performs voltage conversion between the AC bus and the AC motor based on a given first control signal. The second matrix converter is connected to an AC bus, and receives a voltage from an AC power supply outside the vehicle or supplies power to the AC power supply, based on a second control signal applied to the voltage between the AC bus and the AC power supply. Perform the conversion. The inverter is connected between the AC bus and the power storage device, and performs voltage conversion between the AC bus and the power storage device based on a third control signal provided. The control device generates a first control signal based on the required power of the AC motor, generates a second control signal based on a power command value indicating power to be exchanged with an AC power supply outside the vehicle, and an inverter To generate a third control signal so as to adjust the voltage of the AC bus to a predetermined target voltage.

  Preferably, the electric vehicle further includes an AC electric load that operates by receiving AC power, and a third matrix converter. The third matrix converter is connected between the AC bus and the AC electrical load, and performs voltage conversion between the AC bus and the AC electrical load based on the supplied fourth control signal. The control device further generates a fourth control signal based on the required power of the AC electric load, and sets the target voltage based on the required voltage of the AC motor, the required voltage of the AC electric load, and the voltage of the AC power supply. Set.

  More preferably, the control device sets the highest voltage among the required voltage of the AC motor, the required voltage of the AC electric load, and the voltage of the AC power source as the target voltage.

  In the present invention, the power bus is converted to AC, and AC-AC conversion is directly performed by the matrix converter between the in-vehicle AC electric load or the AC power supply outside the vehicle and the AC bus. An inverter is connected between the AC bus and the power storage device, and by controlling the inverter, the voltage of the AC bus is adjusted to a predetermined target voltage so that the voltage of the AC bus does not become unnecessarily high. Therefore, according to the present invention, a highly efficient system is realized.

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

  FIG. 1 is an overall block diagram of a hybrid vehicle shown as an example of an electric vehicle according to an embodiment of the present invention. Referring to FIG. 1, hybrid vehicle 100 includes an AC bus 10, matrix converters 12-1 to 12-4, an inverter 14, motor generators 16-1 and 16-2, drive wheels 18, and an engine 20. And an electric load 22, a power storage device 24, and an ECU (Electronic Control Unit) 26. Hybrid vehicle 100 further includes current sensors 30-1 to 30-5, voltage sensors 32, 34, and 36, and rotational position sensors 38-1 and 38-2.

  AC bus 10 is an electrical path for exchanging three-phase AC power between matrix converters 12-1 to 12-4 and inverter 14. Each of the matrix converters 12-1 to 12-4 is a power converter that realizes direct AC-AC conversion by nine (3 × 3) bidirectional switches (described later).

  Matrix converter 12-1 is connected between AC bus 10 and motor generator 16-1. Matrix converter 12-1 receives three-phase AC power from AC bus 10 and drives motor generator 16-1 based on control signal PWM 1 received from ECU 26. During braking of hybrid vehicle 100, matrix converter 12-1 converts three-phase AC power received from motor generator 16-1 into three-phase AC power synchronized with the voltage of AC bus 10, and the converted three-phase AC power. Electric power is output to the AC bus 10.

  Motor generator 16-1 is a three-phase AC rotating electric machine, and is composed of, for example, a three-phase AC synchronous motor. Motor generator 16-1 is connected to drive wheels 18 and generates a driving force for driving hybrid vehicle 100. Motor generator 16-1 generates electric power by kinetic energy received from drive wheels 18 during braking of hybrid vehicle 100, and outputs the generated three-phase AC power to matrix converter 12-1.

  Matrix converter 12-2 is connected between AC bus 10 and motor generator 16-2. Matrix converter 12-2 converts three-phase AC power received from motor generator 16-2 into three-phase AC power synchronized with the voltage of AC bus 10 based on control signal PWM 2 received from ECU 26. Then, matrix converter 12-2 outputs the converted three-phase AC power to AC bus 10. When engine 20 is started, matrix converter 12-2 receives three-phase AC power from AC bus 10 and power-drives motor generator 16-2 based on control signal PWM2 received from ECU 26.

  Motor generator 16-2 is a three-phase AC rotating electric machine, for example, a three-phase AC synchronous motor. Motor generator 16-2 is connected to engine 20, generates electric power by kinetic energy generated by engine 20, and outputs the generated three-phase AC power to matrix converter 12-2. In addition, when the engine 20 is started, the motor generator 16-2 performs cranking of the engine 20.

  The engine 20 converts thermal energy generated by fuel combustion into kinetic energy of a moving element such as a piston or a rotor, and outputs the converted kinetic energy to the motor generator 16-2. For example, if the motion element is a piston and the motion is a reciprocating motion, the reciprocating motion is converted into a rotational motion via a so-called crank mechanism, and the kinetic energy of the piston is transmitted to the motor generator 16-2. The kinetic energy generated by the engine 20 may be divided and output to the motor generator 16-2 and the drive wheels 18 using a power split device (not shown).

  Matrix converter 12-3 is connected between AC bus 10 and system AC power supply 40 (a three-phase power supply) outside the vehicle. When power is supplied from the system AC power supply 40 to the hybrid vehicle 100, the matrix converter 12-3 synchronizes the three-phase AC power supplied from the system AC power supply 40 with the voltage of the AC bus 10 based on the control signal PWM3 received from the ECU 26. Converted into three-phase AC power. Then, the matrix converter 12-3 outputs the converted three-phase AC power to the AC bus 10. In addition, when power is supplied from the hybrid vehicle 100 to the system AC power supply 40, the matrix converter 12-3 synchronizes the three-phase AC power supplied from the AC bus 10 with the system AC power supply 40 based on the control signal PWM3. Convert to AC power. Then, matrix converter 12-3 outputs the converted three-phase AC power to system AC power supply 40.

  Matrix converter 12-4 is connected between AC bus 10 and electrical load 22. Matrix converter 12-4 receives three-phase AC power from AC bus 10 and drives electric load 22 based on control signal PWM 4 received from ECU 26. The electric load 22 is operable by receiving three-phase AC power, and includes, for example, a compressor for an electric air conditioner.

  The inverter 14 is a DC-AC power converter composed of a three-phase bridge circuit. Inverter 14 is connected between AC bus 10 and power storage device 24. The inverter 14 adjusts the voltage of the AC bus 10 to a predetermined value by transferring power between the AC bus 10 and the power storage device 24. Specifically, inverter 14 converts DC power output from power storage device 24 into three-phase AC power synchronized with the voltage of AC bus 10 based on control signal PWMI received from ECU 26 and outputs the same to AC bus 10. Or by converting the three-phase AC power received from the AC bus 10 into DC power and outputting the DC power to the power storage device 24, the voltage of the AC bus 10 is adjusted to a predetermined value.

  The power storage device 24 is a power buffer for adjusting the voltage of the AC bus 10 to a predetermined value. The power storage device 24 is a DC power source that can be charged and discharged, and includes, for example, a secondary battery such as nickel hydride or lithium ion. As the power storage device 24, a large-capacity capacitor can be used, and any power buffer can be used as long as it temporarily stores the power supplied from the AC bus 10 and can supply the stored power to the AC bus 10 again. It may be a thing.

  Current sensors 30-1 to 30-4 detect currents I1 to I4 input to and output from matrix converters 12-1 to 12-4, respectively, and output them to ECU 26. Current sensor 30-5 detects current I5 input / output to / from inverter 14 and outputs the detected current to ECU 26. The voltage sensor 32 detects the voltage VAC of the AC bus 10 and outputs it to the ECU 26. Voltage sensor 34 detects voltage VB of power storage device 24 and outputs it to ECU 26. Current sensor 35 detects current IB input / output to / from power storage device 24 and outputs the detected current to ECU 26. The voltage sensor 36 detects the voltage VG of the system AC power supply 40 and outputs it to the ECU 26. Rotational position sensors 38-1 and 38-2 detect the rotational angle θ1 of the rotor of motor generator 16-1 and the rotational angle θ2 of the rotor of motor generator 16-2, respectively, and output them to ECU 26.

  ECU26 receives a detection value from each sensor mentioned above. ECU 26 also receives torque target values TR1 and TR2 of motor generators 16-1 and 16-2 from a host ECU (not shown). Based on these values, ECU 26 generates a PWM (Pulse Width Modulation) signal for driving motor generator 16-1, and outputs the generated PWM signal as control signal PWM1 to matrix converter 12-1. To do. Further, ECU 26 generates a PWM signal for driving motor generator 16-2, and outputs the generated PWM signal as control signal PWM2 to matrix converter 12-2. Further, the ECU 26 generates a PWM signal for controlling the matrix converter 12-3 based on a power command value indicating charge / discharge power with the system AC power supply 40, and the generated PWM signal is used as a control signal PWM3 in the matrix. Output to the converter 12-3. Furthermore, ECU 26 generates a PWM signal for driving electric load 22 and outputs the generated PWM signal as control signal PWM4 to matrix converter 12-4. Furthermore, the ECU 26 controls the inverter 14 to generate a PWM signal for adjusting the voltage of the AC bus 10 to the target voltage, and outputs the generated PWM signal to the inverter 14 as the control signal PWMI.

  In this hybrid vehicle 100, an AC bus 10 is provided, and matrix converters 12-1 to 12-4 are connected to the AC bus 10. Electric power is exchanged between motor generators 16-1 and 16-2, electric load 22, and system AC power supply 40 outside the vehicle via AC bus 10. Further, an inverter 14 is further connected to the AC bus 10, and power can be exchanged between the AC bus 10 and the power storage device 24 via the inverter 14. Then, by controlling the inverter 14, the voltage of the AC bus 10 is adjusted so that the voltage of the AC bus 10 does not become unnecessarily high.

  FIG. 2 is a circuit diagram of matrix converters 12-1 to 12-4 shown in FIG. In the following, for convenience of explanation, the terminals 50-1 to 50-3 are referred to as input terminals, and the terminals 52-1 to 52-3 are referred to as output terminals, but are input from the terminals 52-1 to 52-3. It is also possible to convert the three-phase alternating current and output it to the terminals 50-1 to 50-3.

  Referring to FIG. 2, each matrix converter includes bidirectional switches S1 to S9. The bidirectional switches S1 to S9 are on / off controlled in accordance with a control signal from the ECU 26 (FIG. 1). The bidirectional switch S1 is connected between the input terminal 50-1 and the output terminal 52-1. The bidirectional switch S2 is connected between the input terminal 50-1 and the output terminal 52-2. The bidirectional switch S3 is connected between the input terminal 50-1 and the output terminal 52-3. The bidirectional switch S4 is connected between the input terminal 50-2 and the output terminal 52-1. The bidirectional switch S5 is connected between the input terminal 50-2 and the output terminal 52-2. The bidirectional switch S6 is connected between the input terminal 50-2 and the output terminal 52-3. The bidirectional switch S7 is connected between the input terminal 50-3 and the output terminal 52-1. The bidirectional switch S8 is connected between the input terminal 50-3 and the output terminal 52-2. The bidirectional switch S9 is connected between the input terminal 50-3 and the output terminal 52-3.

  Then, by performing PWM control of these bidirectional switches S1 to S9 at a frequency sufficiently higher than the voltage frequency of the AC bus 10, between the input terminals 50-1 to 50-3 and the output terminals 52-1 to 52-3. Can realize AC-AC conversion. As a PWM control method, for example, various known methods such as a method of switching between two wires having the maximum potential difference among three-phase alternating currents, a method of switching using an intermediate voltage, and the like are used. it can.

  FIG. 3 is a circuit diagram showing a configuration of the bidirectional switches S1 to S9 shown in FIG. Referring to FIG. 3, each of bidirectional switches S <b> 1 to S <b> 9 includes power transistors 62 and 64 and diodes 66 and 68. The power transistors 62 and 64 are made of, for example, an IGBT (Insulated Gate Bipolar Transistor).

  Power transistor 62 has a collector connected to terminal 70, an emitter connected to the anode of diode 66, and receives a control signal from ECU 26 (FIG. 1) as a base. The diode 66 has an anode connected to the emitter of the power transistor 62 and a cathode connected to the terminal 72. Power transistor 64 has a collector connected to terminal 72, an emitter connected to the anode of diode 68, and receives a control signal from ECU 26 as a base. The diode 68 has an anode connected to the emitter of the power transistor 64 and a cathode connected to the terminal 70. A connection point between the power transistor 62 and the diode 66 is connected to a connection point between the power transistor 64 and the diode 68.

  In this bidirectional switch, when the control signal from the ECU 26 is activated, the power transistor 62 is turned on, and a current can flow from the terminal 70 to the terminal 72 via the power transistor 62 and the diode 66. When the control signal is activated, the power transistor 64 is also turned on, and a current can be passed from the terminal 72 to the terminal 70 via the power transistor 64 and the diode 68.

  Therefore, when the control signal is activated, if the voltage at the terminal 70 is higher than that at the terminal 72, a current flows from the terminal 70 to the terminal 72 via the power transistor 62 and the diode 66. Since the diode 68 is reverse-biased, no reverse current flows through the power transistor 64. Further, when the control signal is activated, when the voltage at the terminal 72 is higher than that at the terminal 70, a current flows from the terminal 72 to the terminal 70 via the power transistor 64 and the diode 68. Since reverse bias is applied to the diode 66, no reverse current flows through the power transistor 62.

  FIG. 4 is a circuit diagram showing another configuration of the bidirectional switches S1 to S9 shown in FIG. Referring to FIG. 4, each of bidirectional switches S <b> 1 to S <b> 9 includes power transistors 74 and 76. The power transistors 74 and 76 are made of IGBTs with a reverse blocking function. This IGBT with a reverse blocking function has a sufficient withstand voltage even when a reverse voltage is applied to the element.

  Power transistor 74 has a collector and an emitter connected to terminals 70 and 72, respectively, and receives a control signal from ECU 26 (FIG. 1) as a base. Power transistor 76 has a collector and an emitter connected to terminals 72 and 70, respectively, and receives a control signal from ECU 26 as a base.

  In this bidirectional switch, when the control signal is activated, both power transistors 74 and 76 are turned on. Therefore, when the control signal is activated, when the voltage at the terminal 70 is higher than that at the terminal 72, a current flows from the terminal 70 to the terminal 72 via the power transistor 74. Although the power transistor 76 is reverse-biased, the power transistor 76 has a reverse breakdown voltage, so that the element is not destroyed. Further, when the control signal is activated, if the voltage at the terminal 72 is higher than that at the terminal 70, a current flows from the terminal 72 to the terminal 70 via the power transistor 76. Although a reverse bias is applied to the power transistor 74, the power transistor 74 also has a reverse breakdown voltage, so that the element is not destroyed.

  FIG. 5 is a circuit diagram of inverter 14 shown in FIG. Referring to FIG. 5, inverter 14 includes a three-phase bridge circuit, and includes a U-phase arm 80, a V-phase arm 82, and a W-phase arm 84. U-phase arm 80, V-phase arm 82, and W-phase arm 84 are connected in parallel between positive electrode line PL and negative electrode line NL. U-phase arm 80 includes switching elements S11 and S12 and diodes D11 and D12. Switching elements S11 and S12 are connected in series between positive line PL and negative line NL, and diodes D11 and D12 are connected in antiparallel to switching elements S11 and S12, respectively. V-phase arm 82 includes switching elements S13 and S14 and diodes D13 and D14. Switching elements S13 and S14 are connected in series between positive line PL and negative line NL, and diodes D13 and D14 are connected in antiparallel to switching elements S13 and S14, respectively. W-phase arm 84 includes switching elements S15 and S16 and diodes D15 and D16. Switching elements S15 and S16 are connected in series between positive line PL and negative line NL, and diodes D15 and D16 are connected in antiparallel to switching elements S15 and S16, respectively.

  The U-phase line of AC bus 10 (FIG. 1) is connected to the middle point of U-phase arm 80, the V-phase line of AC bus 10 is connected to the middle point of V-phase arm 82, and the middle of W-phase arm 84. The W-phase line of the AC bus 10 is connected to the point. Switching elements S11-S16 are made of, for example, IGBT.

  FIG. 6 is a functional block diagram of ECU 26 shown in FIG. Referring to FIG. 6, ECU 26 includes a rotation speed calculation unit 102, a voltage setting unit 104, a frequency setting unit 106, matrix converter control units 108, 110, 112 and 114, and an inverter control unit 116.

  The rotational speed calculation unit 102 calculates the rotational speed (angular velocity) ω1 of the motor generator 16-1 based on the rotational angle θ1 detected by the rotational position sensor 38-1. Further, the rotation speed calculation unit 102 calculates the rotation speed (angular velocity) ω2 of the motor generator 16-2 based on the rotation angle θ2 detected by the rotation position sensor 38-2. Then, rotation speed calculation unit 102 outputs the calculated rotation speeds ω1 and ω2 to voltage setting unit 104 and frequency setting unit 106.

  Voltage setting unit 104 includes torque target values TR1 and TR2 of motor generators 16-1 and 16-2, a detected value of voltage VG of system AC power supply 40, and motor generators 16-1, 16-2 calculated by rotation speed calculation unit 102. It receives the rotational speeds ω1 and ω2 of 16-2. Then, voltage setting unit 104 sets target voltage VR (effective value) of AC bus 10 based on each of these values, and sets the target voltage VR as matrix converter control units 108, 110, 112, 114 and an inverter. Output to the control unit 116.

  Frequency setting unit 106 receives rotation speeds ω1 and ω2 of motor generators 16-1 and 16-2 calculated by rotation speed calculation unit 102. The frequency setting unit 106 sets the frequency FR of the voltage of the AC bus 10 based on the rotation speeds ω1 and ω2, and sets the set frequency FR to the matrix converter control units 108, 110, 112, 114 and the inverter control unit 116. Output to.

  Matrix converter control unit 108 determines torque target value TR1, target voltage VR and frequency FR of AC bus 10, the detected value of current I1 input to and output from matrix converter 12-1, and rotation angle θ1 of motor generator 16-1. Receive detection value. Based on these values, matrix converter control unit 108 generates control signal PWM1 for driving motor generator 16-1, and outputs the generated control signal PWM1 to matrix converter 12-1.

  Matrix converter control unit 110 receives torque target value TR2, target voltage VR, frequency FR, detected value of current I2 input / output to / from matrix converter 12-2, and detected value of rotation angle θ2 of motor generator 16-2. . Based on these values, matrix converter control unit 110 generates control signal PWM2 for driving motor generator 16-2, and outputs the generated control signal PWM2 to matrix converter 12-2.

  The matrix converter control unit 112 inputs / outputs a power command value PR indicating charge / discharge power with the system AC power supply 40, a detected value of the voltage VG of the system AC power supply 40, a target voltage VR, a frequency FR, and the matrix converter 12-3. The detected value of the current I3 is received. Based on the values, matrix converter control unit 112 generates control signal PWM3 for controlling matrix converter 12-3, and outputs the generated control signal PWM3 to matrix converter 12-3.

  Matrix converter control unit 114 receives required power PRL of electric load 22, target voltage VR, frequency FR, and detected value of current I4 input to and output from matrix converter 12-4. Based on these values, matrix converter control unit 114 generates control signal PWM4 for driving electric load 22, and outputs the generated control signal PWM4 to matrix converter 12-4.

  Inverter control unit 116 receives detection values of target voltage VR, frequency FR, and voltage VAC of AC bus 10. Then, inverter control unit 116 generates control signal PWMI for adjusting voltage VAC of AC bus 10 to target voltage VR and frequency FR, and outputs the generated control signal PWMI to inverter 14.

  FIG. 7 is a detailed functional block diagram of the voltage setting unit 104 shown in FIG. Referring to FIG. 7, voltage setting unit 104 includes required voltage calculation units 120 and 122 and a maximum value selection unit 124. The required voltage calculation unit 120 uses a predetermined map or arithmetic expression for the relationship between the rotational speed and torque of the motor generator 16-1 and the required voltage of the motor generator 16-1, and uses the torque target of the motor generator 16-1. Based on value TR1 and rotation speed ω1 of motor generator 16-1 calculated by rotation speed calculation unit 102, a required voltage of motor generator 16-1 is obtained.

  The required voltage calculation unit 122 uses a predetermined map or arithmetic expression for the relationship between the rotational speed and torque of the motor generator 16-2 and the required voltage of the motor generator 16-2, and the torque target of the motor generator 16-2. Based on value TR2 and rotation speed ω2 of motor generator 16-2 calculated by rotation speed calculation unit 102, a required voltage of motor generator 16-2 is obtained.

  The maximum value selection unit 124 determines the required voltage of the motor generator 16-1 obtained by the required voltage calculation unit 120, the required voltage of the motor generator 16-2 obtained by the required voltage calculation unit 122, and the system AC power supply 40. The voltage VG having the largest effective value level is selected, and the selected voltage is set as the target voltage VR (effective value) of the AC bus 10.

  FIG. 8 is a detailed functional block diagram of the frequency setting unit 106 shown in FIG. Referring to FIG. 8, frequency setting unit 106 includes an average value calculation unit 126 and a limiter 128. Average value calculation unit 126 calculates the average value of rotation speeds ω1 and ω2 of motor generators 16-1 and 16-2, and temporarily sets the calculated value as the frequency of voltage of AC bus 10. The limiter 128 limits the calculated value of the average value calculation unit 126 to a predetermined range when the calculated value of the average value calculation unit 126 exceeds the predetermined range. Then, the limiter 128 sets the output as the frequency FR of the voltage of the AC bus 10.

  FIG. 9 is a detailed functional block diagram of matrix converter control unit 108 shown in FIG. Referring to FIG. 9, matrix converter control unit 108 includes a current command generation unit 130, a current control unit 132, and a PWM signal conversion unit 134. Current command generation unit 130 calculates a target value of current I1 input / output to / from matrix converter 12-1, based on torque target value TR1 of motor generator 16-1. Current control unit 132 receives target voltage VR and frequency FR of AC bus 10 received from voltage setting unit 104 and frequency setting unit 106, the target value of current I1 received from current command generation unit 130, and the detected value of current I1, respectively. Based on the detected value of the rotation angle θ1 of the motor generator 16-1, a modulated wave for controlling the current I1 to the target value is generated. The PWM signal conversion unit 134 generates a control signal PWM1 for turning on / off the bidirectional switch of the matrix converter 12-1 based on the modulated wave generated by the current control unit 132 and a predetermined carrier signal. The generated control signal PWM1 is output to the matrix converter 12-1.

  FIG. 10 is a detailed functional block diagram of matrix converter control unit 110 shown in FIG. Referring to FIG. 10, matrix converter control unit 110 includes a current command generation unit 136, a current control unit 138, and a PWM signal conversion unit 140. Current command generation unit 136 calculates a target value of current I2 input to and output from matrix converter 12-2 based on torque target value TR2 of motor generator 16-2. Current control unit 138 detects target voltage VR and frequency FR of AC bus 10, target value of current I2 received from current command generation unit 136, detection value of current I2, and rotation angle θ2 of motor generator 16-2. Based on the value, a modulated wave for controlling the current I2 to the target value is generated. The PWM signal conversion unit 140 generates a control signal PWM2 for turning on / off the bidirectional switch of the matrix converter 12-2 based on the modulated wave generated by the current control unit 138 and a predetermined carrier signal. The generated control signal PWM2 is output to the matrix converter 12-2.

  FIG. 11 is a detailed functional block diagram of matrix converter control unit 112 shown in FIG. Referring to FIG. 11, matrix converter control unit 112 includes a current command generation unit 142, a current control unit 144, and a PWM signal conversion unit 146. The current command generator 142 is input to and output from the matrix converter 12-3 based on the power command value PR indicating the target amount of power exchanged with the system AC power supply 40 and the detected value of the voltage VG of the system AC power supply 40. The target value of the current I3 is calculated. Current control unit 144 controls current I3 to be a target value based on target voltage VR and frequency FR of AC bus 10, the target value of current I3 received from current command generation unit 142, and the detected value of current I3. For generating a modulated wave. The PWM signal conversion unit 146 generates a control signal PWM3 for turning on / off the bidirectional switch of the matrix converter 12-3 based on the modulated wave generated by the current control unit 144 and a predetermined carrier signal. The generated control signal PWM3 is output to the matrix converter 12-3.

  FIG. 12 is a detailed functional block diagram of matrix converter control unit 114 shown in FIG. Referring to FIG. 12, matrix converter control unit 114 includes a current command generation unit 148, a current control unit 150, and a PWM signal conversion unit 152. Current command generation unit 148 calculates a target value of current I4 input / output to / from matrix converter 12-4 based on required power PRL of electric load 22. Current control unit 150 controls current I4 to be a target value based on target voltage VR and frequency FR of AC bus 10, a target value of current I4 received from current command generation unit 148, and a detected value of current I4. For generating a modulated wave. The PWM signal converter 152 generates a control signal PWM4 for turning on / off the bidirectional switch of the matrix converter 12-4 based on the modulated wave generated by the current controller 150 and a predetermined carrier signal, The generated control signal PWM4 is output to the matrix converter 12-4.

  FIG. 13 is a detailed functional block diagram of inverter control unit 116 shown in FIG. Referring to FIG. 13, inverter control unit 116 includes a CVCF control unit 154 and a PWM signal conversion unit 156. The CVCF control unit 154 adjusts the voltage VAC of the AC bus 10 to the target voltage VR and the frequency FR based on the target voltage VR and frequency FR of the AC bus 10 and the detected value of the voltage VAC of the AC bus 10. Generate a modulated wave. The PWM signal conversion unit 156 generates a control signal PWMI for turning on / off the switching element of the inverter 14 based on the modulated wave generated by the CVCF control unit 154 and a predetermined carrier signal, and the generated control signal PWMI is output to the inverter 14.

  As described above, in this embodiment, AC bus 10 is provided, and a matrix converter is provided between motor generators 16-1 and 16-2, electric load 22, and system AC power supply 40 outside vehicle and AC bus 10. The direct AC-AC conversion is performed by. In addition, an inverter 14 is further connected to the AC bus 10, and the voltage of the AC bus 10 is adjusted by the inverter 14. Here, the voltage of AC bus 10 is adjusted to the required voltage of motor generators 16-1 and 16-2 and voltage VG of system AC power supply 40 according to the highest effective value level. That is, the voltage of the AC bus 10 is adjusted to a necessary minimum level. Therefore, according to this embodiment, a highly efficient system is realized.

  In the above embodiment, the system AC power supply 40 is a three-phase power supply, but may be a single-phase power supply. In this case, the matrix converter 12-3 is configured by a 2 × 3 bidirectional switch. Moreover, although the system | strain AC power supply 40 shall be connected to the matrix converter 12-3, the electric power feeding from the system | strain AC power supply 40 to the matrix converter 12-3 may be performed non-contactingly. For example, as a non-contact power transmission technology, power transmission using electromagnetic induction, power transmission using radio waves, power transmission by a resonance method, and the like are known. From these methods, the system AC power supply 40 to the matrix converter 12-3 is known. Power can be supplied without contact.

  In the above description, power can be exchanged bidirectionally between the system AC power supply 40 and the hybrid vehicle 100. However, power supply from the system AC power supply 40 to the hybrid vehicle 100 and from the hybrid vehicle 100 to the system AC power supply 40 are possible. Only one of the power supplies may be possible.

  In the above, a boost converter that adjusts the DC voltage applied to the inverter to be equal to or higher than the voltage of the power storage device 24 may be further provided between the inverter 14 and the power storage device 24.

  In the above description, the hybrid vehicle has been described as an example of the electric vehicle. However, the present invention further includes an electric vehicle that does not include the engine 20 and runs only by electric power, and a fuel cell in addition to the power storage device as a DC power source. It can also be applied to fuel cell vehicles.

  In the above, motor generators 16-1, 16-2 and electric load 22 correspond to the “AC electric load” in the present invention, and matrix converters 12-1, 12-2, 12-4 in the present invention. This corresponds to the “first matrix converter”. The matrix converter 12-3 corresponds to the “second matrix converter” in the present invention, and the ECU 26 corresponds to the “control device” in the present invention.

  Further, the motor generator 16-1 corresponds to the “AC motor” in the present invention, and the matrix converter 12-1 in the present invention “the first matrix that performs voltage conversion between the AC bus and the AC motor”. Corresponds to "converter". Further, motor generator 16-2 corresponds to “AC electric load” in the present invention, and matrix converter 12-2 corresponds to “third matrix converter” in the present invention.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

1 is an overall block diagram of a hybrid vehicle shown as an example of an electric vehicle according to an embodiment of the present invention. It is a circuit diagram of the matrix converter shown in FIG. FIG. 3 is a circuit diagram showing a configuration of a bidirectional switch shown in FIG. 2. FIG. 3 is a circuit diagram showing another configuration of the bidirectional switch shown in FIG. 2. It is a circuit diagram of the inverter shown in FIG. It is a functional block diagram of ECU shown in FIG. It is a detailed functional block diagram of the voltage setting part shown in FIG. It is a detailed functional block diagram of the frequency setting part shown in FIG. FIG. 7 is a detailed functional block diagram of a matrix converter control unit shown in FIG. 6. It is a detailed functional block diagram of the matrix converter control part 110 shown in FIG. It is a detailed functional block diagram of the matrix converter control part 112 shown in FIG. It is a detailed functional block diagram of the matrix converter control part 114 shown in FIG. It is a detailed functional block diagram of the inverter control part shown in FIG.

Explanation of symbols

  10 AC Bus, 12-1 to 12-4 Matrix Converter, 14 Inverter, 16-1, 16-2 Motor Generator, 18 Drive Wheel, 20 Engine, 22 Electric Load, 24 Power Storage Device, 26 ECU, 30-1 to 30 -5, 35 Current sensor, 32, 34, 36 Voltage sensor, 38-1, 38-2 Rotation position sensor, 40 AC power supply, 62, 64, 74, 76 Power transistor, 66, 68 Diode, 80 U phase arm , 82 V-phase arm, 84 W-phase arm, 100 hybrid vehicle, 102 rotation speed calculation unit, 104 voltage setting unit, 106 frequency setting unit, 108, 110, 112, 114 matrix converter control unit, 116 inverter control unit, 120, 122 required voltage calculation unit, 124 maximum value selection unit, 126 average Calculation unit, 128 limiter, 130, 136, 142, 148 Current command generation unit, 132, 138, 144, 150 Current control unit, 134, 140, 146, 152, 156 PWM signal conversion unit, 154 CVCF control unit, S1 S9 Bidirectional switch, PL positive line, NL negative line, S11 to S16 switching element, D11 to D16 diode.

Claims (6)

A power supply system for a vehicle configured to be capable of executing at least one of power reception from an AC power supply outside the vehicle and power supply to the AC power supply, wherein the vehicle operates by receiving a chargeable / dischargeable power storage device and AC power With an AC electrical load
An AC bus for energizing the AC power;
A first matrix converter connected between the AC bus and the AC electrical load, and performing voltage conversion between the AC bus and the AC electrical load based on a given first control signal;
A second converter connected to the AC bus and performing voltage conversion between the AC bus and the AC power source based on a second control signal applied when receiving power from the AC power source or when supplying power to the AC power source; Matrix converter with
An inverter connected between the AC bus and the power storage device, and performing voltage conversion between the AC bus and the power storage device based on a given third control signal;
The first control signal is generated based on the required power of the AC electric load, the second control signal is generated based on a power command value that instructs power to be exchanged with the AC power supply, and the inverter And a control device that generates the third control signal so as to adjust the voltage of the AC bus to a predetermined target voltage.   The power supply system according to claim 1, wherein the control device sets the target voltage based on a required voltage of the AC electric load and a voltage of the AC power supply.   The power supply system according to claim 2, wherein the control device sets a higher one of a required voltage of the AC electric load and a voltage of the AC power supply as the target voltage. An electric vehicle capable of executing at least one of power reception from an AC power supply outside the vehicle and power supply to the AC power supply,
A chargeable / dischargeable power storage device;
An AC motor that generates AC driving power by receiving AC power;
An AC bus for energizing the AC power;
A first matrix converter connected between the AC bus and the AC motor and performing voltage conversion between the AC bus and the AC motor based on a first control signal applied;
A second converter connected to the AC bus and performing voltage conversion between the AC bus and the AC power source based on a second control signal applied when receiving power from the AC power source or when supplying power to the AC power source; Matrix converter
An inverter connected between the AC bus and the power storage device and performing voltage conversion between the AC bus and the power storage device based on a given third control signal;
The first control signal is generated based on the required power of the AC motor, the second control signal is generated based on a power command value instructing the power exchanged with the AC power supply, and the inverter An electric vehicle comprising: a control device that generates the third control signal so as to adjust the voltage of the AC bus to a predetermined target voltage. AC electrical load that operates in response to the AC power;
A third matrix converter connected between the AC bus and the AC electrical load and performing voltage conversion between the AC bus and the AC electrical load based on a fourth control signal applied thereto; ,
The control device further generates the fourth control signal based on the required power of the AC electric load, and based on the required voltage of the AC motor, the required voltage of the AC electric load, and the voltage of the AC power supply. The electric vehicle according to claim 4, wherein the target voltage is set.   The electric vehicle according to claim 5, wherein the control device sets the highest voltage among the required voltage of the AC motor, the required voltage of the AC electric load, and the voltage of the AC power supply as the target voltage.

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