JP2006101594A - Power output unit and vehicle equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power output unit capable of generating a desired alternating-current voltage even when an alternating-current output of such a voltage level that it cannot be supplemented for by a preset system voltage is requested. <P>SOLUTION: The power output device 100 is capable of generating alternating-current voltage between the neutral points of motor generators MG1 and MG2 and outputting it. In this power output device, system voltage Vdc is allotted to a drive control portion and an alternating-current voltage allotted portion in each of the motor generators MG1 and MG2. When the alternating-current voltage allotted portion becomes insufficient because of a high-voltage alternating current output request, the power output unit 100 ensures the alternating-current voltage allotted portion to generate a desired alternating-current voltage. For this purpose, it carries out field weakening control on the motor generator MG1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power output apparatus and a vehicle including the same, and more particularly to a power output apparatus capable of generating a commercial AC voltage and outputting it to an external AC load and a vehicle including the same.

Patent Document 1 discloses a motor driving / charging system capable of generating AC power and outputting it to the outside. The motor driving / charging system includes a battery, two motors, two inverters connected to the two motors, and an input / output port connected to each neutral point of the two motors. According to this motor driving / charging system, an AC voltage can be generated between the neutral points of the two motors and output from the input / output port (see Patent Document 1).
US Pat. No. 5,099,186

  In such a system that generates and outputs an AC voltage between the neutral points of two motors, if the motor drive and the output of the AC voltage are required at the same time, the AC voltage may not be generated. That is, in such a system, it is necessary to distribute the system voltage (that is, the inverter input voltage) between the motor drive part and the AC voltage part. When a high-voltage AC output is required, the AC voltage part is insufficient. Can occur.

  For example, when the system voltage is set in accordance with Japan's commercial AC voltage AC100V, in countries where the commercial AC voltage is higher than Japan (such as AC220V), output of AC voltage is required in accordance with the country's commercial AC voltage. Then, a situation may occur in which a desired AC voltage cannot be generated with the system voltage.

  The motor driving / charging system disclosed in Patent Document 1 described above does not assume the above situation, and may not generate a desired AC voltage when a high-voltage AC output is required.

  Therefore, the present invention has been made to solve such a problem, and an object of the present invention is to generate a desired AC voltage even when an AC output having a voltage level that cannot be compensated for by a set system voltage is required. It is providing the power output device which can do.

  Another object of the present invention is to provide a vehicle equipped with a power output device that can generate a desired AC voltage even when an AC output having a voltage level that cannot be compensated by a set system voltage is required. It is.

  According to the present invention, the power output apparatus includes first and second motor generators, first and second inverters connected to the first and second motor generators, respectively, and receiving a system voltage from the voltage supply line. The first and second inverters operate to drive the first and second motor generators using the system voltage and to generate an AC voltage between the neutral points of the first and second motor generators. A control device for controlling the motor, and when there is an AC voltage output request having a voltage level that cannot be generated by the system voltage, the control device weakens one or both of the first and second motor generators. The operation of the first and / or second inverter is controlled so as to perform field control.

  Preferably, the first motor generator is connected to an internal combustion engine of the vehicle, and the second motor generator is connected to a drive wheel of the vehicle, and there is a request for output of an AC voltage having a voltage level that cannot be generated by a system voltage. The control device controls the operation of the first inverter so as to perform field weakening control on the first motor generator.

  According to the invention, the power output apparatus includes first and second motor generators, a DC power supply, a boost converter that boosts a DC voltage output from the DC power supply to a system voltage, and the first and second motor generators. The first and second inverters respectively connected to the motor generators for receiving the system voltage from the boost converter and the operation of the boost converter are controlled, and the first and second motor generators are driven using the system voltage. And a control device for controlling the operation of the first and second inverters so as to generate an AC voltage between the neutral points of the first and second motor generators, from a voltage level that cannot be generated by the system voltage. When there is an AC voltage output request, the controller operates the boost converter to raise the system voltage Control to.

  According to the invention, the power output apparatus includes first and second motor generators, a DC power supply, a boost converter that boosts a DC voltage output from the DC power supply to a system voltage, and the first and second motor generators. The first and second inverters respectively connected to the motor generators for receiving the system voltage from the boost converter and the operation of the boost converter are controlled, and the first and second motor generators are driven using the system voltage. And a control device that controls the operation of the first and second inverters so as to generate an AC voltage between the neutral points of the first and second motor generators. When there is an AC voltage output request having a voltage level that cannot be generated by a system voltage having a level, the first and second motor generators Controls the operation of the first and / or second inverters so as to perform field-weakening control on one or both of the oscillators, and even a system voltage composed of a second voltage level higher than the first voltage level is generated. When there is an AC voltage output request having a voltage level that cannot be achieved, the operation of the boost converter is controlled so as to increase the system voltage.

  Preferably, the first motor generator is connected to an internal combustion engine of the vehicle, and the second motor generator is connected to a drive wheel of the vehicle, and an alternating current having a voltage level that cannot be generated by a system voltage having the first voltage level. When there is a voltage output request, the control device controls the operation of the first inverter so as to perform field-weakening control on the first motor generator.

  According to the invention, the vehicle includes any one of the power output devices described above. The power output device drives the drive wheels and supplies the generated AC voltage to the external AC load.

  Preferably, the vehicle further includes an internal combustion engine, the first motor generator included in the power output device is connected to the internal combustion engine, and the second motor generator included in the power output device is connected to the drive wheels, The second motor generator drives the drive wheels.

  In the power output apparatus according to the present invention, an AC voltage that can be output to an external AC load is generated between the neutral points of the first and second motor generators. When there is an AC voltage output request having a voltage level that cannot be generated with the set system voltage, the control device performs field weakening control on the motor generator, so that the electromotive force of the motor generator controlled by field weakening is reduced. The generated voltage margin is used for the AC voltage shortage.

  Therefore, according to the present invention, even when a high voltage AC output is required, a desired AC voltage is generated between the neutral points of the first and second motor generators without increasing the system voltage. Can do.

  In the power output apparatus according to the present invention, when there is an output request for an AC voltage having a voltage level that cannot be generated with the set system voltage, the control apparatus includes a first motor generator coupled to the internal combustion engine of the vehicle. Therefore, the operation of the second motor generator connected to the drive wheels of the vehicle is not affected.

  Therefore, according to the present invention, a desired AC voltage can be generated between the neutral points of the first and second motor generators without affecting the running function of the vehicle.

  In the power output device according to the present invention, when there is an AC voltage output request having a voltage level that cannot be generated with the set system voltage, the control device controls the operation of the boost converter so as to increase the system voltage. The increased voltage is used for the AC voltage shortage.

  Therefore, according to the present invention, even when a high voltage AC output is required, a desired AC voltage can be generated between the neutral points of the first and second motor generators.

  In the power output apparatus according to the present invention, when the control device has requested to output an AC voltage having a voltage level that cannot be generated by the system voltage having the first voltage level, the control device has the first and second motor generators. A voltage that cannot be generated even by a system voltage composed of a second voltage level higher than the first voltage level by controlling the operation of the first and / or second inverter so as to perform field-weakening control on one or both of them. When there is a request to output AC voltage consisting of levels, the operation of the boost converter is controlled so as to increase the system voltage. When the voltage shortage is relatively small, field weakening control of the motor generator is performed, and the voltage shortage When it is large, the system voltage rises.

  Therefore, according to the present invention, it is possible to flexibly cope with a wide range of AC output. Moreover, the efficiency fall by field weakening control can be suppressed to a fixed range.

  In addition, the vehicle according to the present invention includes the power output device described above, and the power output device drives the drive wheels of the vehicle, generates an AC voltage, and supplies the AC voltage to the external AC load.

  Therefore, according to the present invention, even when a high voltage AC output is required, a desired AC voltage can be generated and supplied to the external AC load. In addition, since a dedicated inverter for generating an AC voltage is not provided, it is possible to realize a reduction in size, weight, and cost while having an additional function as an AC power source.

  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.

[Embodiment 1]
1 is a schematic block diagram of a power output apparatus according to Embodiment 1 of the present invention. Referring to FIG. 1, power output device 100 includes a battery B, a boost converter 10, inverters 20 and 30, motor generators MG1 and MG2, an AC port 40, a connector 50, a control device 60, Capacitors C1 and C2, power supply lines PL1 and PL2, ground line SL, U-phase lines UL1 and UL2, V-phase lines VL1 and VL2, W-phase lines WL1 and WL2, and AC output lines ACL1 and ACL2 Prepare.

  The power output apparatus 100 is mounted on, for example, a hybrid vehicle. Motor generator MG1 is incorporated in the hybrid vehicle as operating as a generator driven by an engine and operating as an electric motor capable of starting the engine. Motor generator MG2 is incorporated in the hybrid vehicle as an electric motor that drives the drive wheels of the hybrid vehicle.

  Motor generators MG1, MG2 are made of, for example, a three-phase AC synchronous motor. Motor generator MG <b> 1 generates an AC voltage using the rotational force from the engine, and outputs the generated AC voltage to inverter 20. Motor generator MG1 generates driving force by the AC voltage received from inverter 20, and starts the engine. Motor generator MG <b> 2 generates vehicle driving torque by the AC voltage received from inverter 30. Motor generator MG2 generates an alternating voltage and outputs it to inverter 30 during regenerative braking.

  The battery B, which is a direct current power source, is composed of, for example, a secondary battery such as nickel metal hydride or lithium ion. Battery B outputs the generated DC voltage to boost converter 10 and is charged by the DC voltage output from boost converter 10.

  Boost converter 10 includes a reactor L1, npn transistors Q1 and Q2, and diodes D1 and D2. Reactor L1 has one end connected to power supply line PL1, and the other end connected to the connection point of npn transistors Q1 and Q2. Npn transistors Q1 and Q2 are connected in series between power supply line PL2 and ground line SL, and receive control signal PWC from control device 60 as a base. Diodes D1 and D2 are connected between the collectors and emitters of npn transistors Q1 and Q2, respectively, so that current flows from the emitter side to the collector side.

  Inverter 20 includes a U-phase arm 21, a V-phase arm 22 and a W-phase arm 23. U-phase arm 21, V-phase arm 22 and W-phase arm 23 are connected in parallel between power supply line PL2 and ground line SL. The U-phase arm 21 is composed of npn transistors Q11 and Q12 connected in series, the V-phase arm 22 is composed of npn transistors Q13 and Q14 connected in series, and the W-phase arm 23 is connected in series. Npn transistors Q15 and Q16. Further, diodes D11 to D16 that flow current from the emitter side to the collector side are connected between the collectors and emitters of the npn transistors Q11 to Q16, respectively.

  A connection point of each npn transistor in each phase arm is connected to an anti-neutral point side of each phase coil of motor generator MG1 via U, V, W phase lines UL1, VL1, WL1.

  Inverter 30 includes a U-phase arm 31, a V-phase arm 32, and a W-phase arm 33. U-phase arm 31, V-phase arm 32 and W-phase arm 33 are connected in parallel between power supply line PL2 and ground line SL. The U-phase arm 31 is composed of npn transistors Q21 and Q22 connected in series, the V-phase arm 32 is composed of npn transistors Q23 and Q24 connected in series, and the W-phase arm 33 is connected in series. Npn transistors Q25 and Q26. In addition, diodes D21 to D26 that flow current from the emitter side to the collector side are connected between the collector and emitter of each of the npn transistors Q21 to Q26.

  Also in inverter 30, the connection point of each npn transistor in each phase arm is on the anti-neutral point side of each phase coil of motor generator MG2 via U, V, W phase lines UL2, VL2, WL2. Each is connected.

  Capacitor C1 is connected between power supply line PL1 and ground line SL, and reduces the influence on battery B and boost converter 10 due to voltage fluctuation. Capacitor C2 is connected between power supply line PL2 and ground line SL, and reduces the influence on inverters 20 and 30 and boost converter 10 due to voltage fluctuation.

  Boost converter 10 boosts the DC voltage from battery B by accumulating current flowing in accordance with the switching operation of npn transistor Q2 as magnetic field energy in reactor L1, based on control signal PWC from control device 60, The boosted boosted voltage is output to the power supply line PL2 via the diode D1 in synchronization with the timing when the npn transistor Q2 is turned off. Boost converter 10 steps down DC voltage received from inverters 20 and / or 30 via power supply line PL2 to voltage level of battery B based on control signal PWC from control device 60, and charges battery B. .

  Hereinafter, the voltage of power supply line PL2 generated by boost converter 10 is also referred to as “system voltage Vdc”.

  Inverter 20 converts system voltage Vdc received from power supply line PL2 into an AC voltage based on control signal PWM1 from control device 60, and outputs the AC voltage to motor generator MG1. Thereby, motor generator MG1 is driven to generate a desired torque. Inverter 20 also converts AC voltage generated by motor generator MG1 into DC voltage based on control signal PWM1 from control device 60, and outputs the converted DC voltage to power supply line PL2.

  Here, inverter 20 controls the potential of neutral point N1 based on control signal PWM1 from control device 60 so as to generate commercial AC voltage Vac between neutral points N1 and N2 of motor generators MG1 and MG2. At the same time, the motor generator MG1 is driven.

  Further, when there is a request for outputting commercial AC voltage Vac having a voltage level that cannot be compensated for by system voltage Vdc, inverter 20 is based on control signal PWM1 from control device 60 so that field weakening control is performed in motor generator MG1. To drive motor generator MG1. More specifically, inverter 20 generates a d-axis current component in a direction that weakens the field of motor generator MG1 based on control signal PWM1 from control device 60, and outputs the d-axis current component to motor generator MG1.

  Inverter 30 converts system voltage Vdc received from power supply line PL2 into an AC voltage based on control signal PWM2 from control device 60, and outputs the AC voltage to motor generator MG2. Thereby, motor generator MG2 is driven to generate a desired torque. Further, inverter 30 converts the AC voltage output from motor generator MG2 into a DC voltage based on control signal PWM2 from control device 60 during regenerative braking of motor generator MG2, and converts the converted DC voltage to a power supply line. Output to PL2.

  Here, inverter 30 controls the potential of neutral point N2 based on control signal PWM2 from control device 60 so as to generate commercial AC voltage Vac between neutral points N1 and N2 of motor generators MG1 and MG2. At the same time, the motor generator MG2 is driven.

  AC port 40 includes a relay for connecting / disconnecting AC output lines ACL1, ACL2 and connector 50, a voltage sensor for detecting commercial AC voltage Vac and AC current Iac generated on AC output lines ACL1, ACL2, respectively. Including current sensors. When AC port 40 receives output permission instruction EN from control device 60, AC port 40 electrically connects AC output lines ACL1 and ACL2 to connector 50. AC port 40 detects commercial AC voltage Vac and AC current Iac in AC output lines ACL 1 and ACL 2, and outputs the detected commercial AC voltage Vac and AC current Iac to control device 60.

  Connector 50 is an output terminal for outputting commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 to an external AC load. A power outlet is connected. Connector 50 outputs H level signal CT to control device 60 when an external AC load outlet is connected.

  Control device 60 is a control signal for driving boost converter 10 based on torque command values and motor speeds of motor generators MG1 and MG2, the battery voltage of battery B, and the voltage (system voltage Vdc) of power supply line PL2. PWC is generated, and the generated control signal PWC is output to boost converter 10. The rotational speeds of motor generators MG1 and MG2, the voltage of battery B, and the voltage of power supply line PL2 are detected by sensors (not shown).

  Control device 60 generates control signal PWM1 for driving motor generator MG1 based on system voltage Vdc and motor current and torque command value of motor generator MG1.

  Here, control device 60 includes upper arm npn transistors Q11, Q13, Q15 and lower arm npn transistors so that commercial AC voltage Vac is generated between neutral points N1, N2 of motor generators MG1, MG2. A control signal PWM1 is generated while controlling the sum of the duties with Q12, Q14, and Q16.

  Furthermore, when there is a request for outputting commercial AC voltage Vac having a voltage level that cannot be compensated for by system voltage Vdc, control device 60 performs field-weakening control of motor generator MG1. In other words, control device 60 generates control signal PWM1 such that inverter 20 generates a d-axis current component in a direction that weakens the field of motor generator MG1 and outputs the same to motor generator MG1. Then, control device 60 outputs the generated control signal PWM1 to inverter 20.

  Further, control device 60 generates control signal PWM2 for driving motor generator MG2 based on system voltage Vdc and motor current and torque command value of motor generator MG2. Here, control device 60 includes upper arm npn transistors Q21, Q23, Q25 and lower arm npn transistors so that commercial AC voltage Vac is generated between neutral points N1, N2 of motor generators MG1, MG2. A control signal PWM2 is generated while controlling the sum of the duties with Q22, Q24, and Q26. Then, control device 60 outputs the generated control signal PWM2 to inverter 30.

  FIG. 2 is a diagram for explaining a current that flows through motor generators MG1 and MG2 to generate commercial AC voltage Vac between neutral points N1 and N2 of motor generators MG1 and MG2 shown in FIG. FIG. 2 representatively shows the case where AC current Iac flows from neutral point N1 of motor generator MG1 to neutral point N2 of motor generator MG2, and the field weakening control of motor generator MG1 described above. Is shown when not done.

  Referring to FIG. 2, inverter 20 (not shown) connected to U, V, W phase lines UL1, VL1, WL1 receives control signal PWM1 from control device 60 (not shown, the same applies hereinafter). Based on the switching operation, a U-phase current consisting of current components Iu1_t and Iu1_ac is passed through the U-phase coil of the motor generator MG1, a V-phase current consisting of current components Iv1_t and Iv1_ac is passed through the V-phase coil of the motor generator MG1, A W-phase current composed of current components Iw1_t and Iw1_ac is passed through the W-phase coil of motor generator MG1.

  An inverter 30 (not shown) connected to the U, V, W phase lines UL2, VL2, WL2 performs a switching operation based on the control signal PWM2 from the control device 60, and from the current components Iu2_t, Iu2_ac. A U-phase current consisting of current components Iv2_t and Iv2_ac is supplied to a V-phase coil of motor generator MG2, and a W-phase current consisting of current components Iw2_t and Iw2_ac is supplied to motor generator MG2. Flow through the W-phase coil.

  Here, current components Iu1_t, Iv1_t, and Iw1_t are currents for generating torque in motor generator MG1, and current components Iu2_t, Iv2_t, and Iw2_t are currents for generating torque in motor generator MG2. Further, current components Iu1_ac, Iv1_ac, Iw1_ac are currents for flowing AC current Iac from neutral point N1 of motor generator MG1 to AC output line ACL1, and current components Iu2_ac, Iv2_ac, Iw2_ac are from AC output line ACL2. This is a current for flowing alternating current Iac to neutral point N2 of motor generator MG2. Current components Iu1_ac, Iv1_ac, Iw1_ac, Iu2_ac, Iv2_ac, and Iw2_ac have the same magnitude and do not contribute to the torque of motor generators MG1 and MG2. Then, each of the total value of the current components Iu1_ac, Iv1_ac, Iw1_ac and the total value of the current components Iu2_ac, Iv2_ac, Iw2_ac becomes the alternating current Iac.

  FIG. 3 is a waveform diagram of the duty sum and the commercial AC voltage Vac. With reference to FIG. 3, a curve k <b> 1 shows a change in the total duty in the switching control of inverter 20, and a curve k <b> 2 shows a change in the total duty in switching control of inverter 30. Here, the total sum of duty is obtained by subtracting the on-duty of the lower arm from the on-duty of the upper arm in each inverter. In FIG. 3, when the sum of the duty is positive, the neutral point potential of the corresponding motor generator is an intermediate value (Vdc / 2) of system voltage Vdc (voltage of power supply line PL2 shown in FIG. 1), which is the inverter input voltage. When the sum of the duty is negative, the neutral point potential is lower than the voltage Vdc / 2.

  In power output device 100, control device 60 periodically changes the total duty of inverter 20 at the commercial frequency according to curve k1, and periodically changes the total duty of inverter 30 at the commercial frequency according to curve k2. . Here, the sum total of the duty of the inverter 30 is periodically changed by a phase obtained by inverting the phase where the sum of the duty of the inverter 20 changes.

  Then, at time t0 to t1, the potential at the neutral point N1 is higher than the voltage Vdc / 2, the potential at the neutral point N2 is lower than the voltage Vdc / 2, and the neutral point N1 is between N1 and N2. A positive-side commercial AC voltage Vac is generated. Here, when the outlet of the external AC load is connected to the connector 50, the surplus current that cannot flow from the upper arm to the lower arm of the inverter 20 starts from the neutral point N1 to the AC output line ACL1, the external AC load, and the AC output. It flows to the neutral point N2 through the line ACL2, and flows from the neutral point N2 to the lower arm of the inverter 30.

  From time t1 to t2, the potential at the neutral point N1 is lower than the voltage Vdc / 2, the potential at the neutral point N2 is higher than the voltage Vdc / 2, and is negative between the neutral points N1 and N2. Side commercial AC voltage Vac is generated. The surplus current that cannot flow from the upper arm to the lower arm of the inverter 30 flows from the neutral point N2 to the neutral point N1 via the AC output line ACL2, the external AC load, and the AC output line ACL1, and the neutral point. N1 flows to the lower arm of the inverter 20.

  In this way, inverters 20 and 30 can generate commercial AC voltage Vac between neutral points N1 and N2 of motor generators MG1 and MG2 while driving and controlling motor generators MG1 and MG2.

  As described above, inverters 20 and 30 control motor potentials at neutral points N1 and N2, respectively, so that commercial AC voltage Vac is generated between neutral points N1 and N2 of motor generators MG1 and MG2. It is necessary to control the driving of MG1 and MG2. That is, in this power output apparatus 100, system voltage Vdc, which is the input voltage of inverters 20 and 30, is supplied to each motor generator MG1 and MG2 for drive control (torque voltage generation) and neutral point potential (commercial AC voltage Vac Production).

  For example, when there is a request to output a commercial AC voltage Vac composed of a high voltage such as AC 220 V, the system voltage Vdc lacks the neutral point potential in each motor generator MG1, MG2, and the desired commercial AC voltage Vac can be generated. In this power output device 100, desired commercial AC voltage Vac can be generated by performing field weakening control of motor generator MG1 by control device 60 as described above.

  Here, field weakening control is generally to reduce the motor electromotive force that increases according to the number of rotations of the motor by weakening the field and to control the motor to a high rotation range. In this power output device 100, by generating a commercial AC voltage Vac by using a margin of voltage generated by reducing the electromotive force of motor generator MG1 by weakening the field of motor generator MG1 (that is, voltage margin). This is used to secure the voltage for generating the commercial AC voltage Vac.

  In this power output apparatus 100, motor generators MG1 and MG2 are constituted by a rotor embedded with permanent magnets and a stator wound with a stator coil, and a field is generated by the permanent magnets embedded in the rotor. The The field weakening control of motor generator MG1 is realized by causing inverter 20 to flow a d-axis current component in the direction of weakening the field of motor generator MG1 through the stator coil of motor generator MG1.

  FIG. 4 is a diagram for explaining the concept of voltage distribution in motor generators MG1 and MG2 when commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 is AC100V. Referring to FIG. 4, system voltage Vdc supplied to inverters 20 and 30 generates AC 100V between drive control components for generating torque and neutral points N1 and N2 in each of motor generators MG1 and MG2. It is used for AC voltage share for

  Here, the AC voltage share in motor generator MG1 is a voltage that contributes to the potential generation of neutral point N1 of motor generator MG1, and the AC voltage share in motor generator MG2 is the neutral point N2 of motor generator MG2. A voltage that contributes to potential generation, and the sum of the AC voltage share in motor generator MG1 and the AC voltage share in motor generator MG2 (shaded portion in the figure) is between neutral points N1 and N2 of motor generators MG1 and MG2. Corresponds to AC100V generated.

  When commercial AC voltage Vac is 100 V AC, in each of motor generators MG1 and MG2, the sum of the drive control voltage and AC voltage share voltage is equal to or lower than system voltage Vdc, and inverters 20 and 30 are connected to motor generator. A commercial AC voltage Vac composed of 100 VAC can be generated between the neutral points N1 and N2 while driving and controlling the MG1 and MG2, respectively.

  5 and 6 are diagrams for explaining the concept of voltage distribution in motor generators MG1 and MG2 when commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 is AC 220V. . FIG. 5 shows voltage distribution when field weakening control of motor generator MG1 is not performed, and FIG. 6 shows voltage distribution when field weakening control of motor generator MG1 is performed. 5 and 6, the case where the commercial AC voltage Vac generated between the neutral points N1 and N2 is a high voltage is shown as an example in which the commercial AC voltage Vac is AC 220V. The voltage level of the commercial AC voltage Vac is not limited to AC220V.

  Referring to FIG. 5, since commercial AC voltage Vac is a high voltage of AC 220 V, the AC voltage share (hatched portion in the figure) in each of motor generators MG1 and MG2 is greater than that of AC 100 V shown in FIG. In addition, in each of motor generators MG1 and MG2, the sum of the voltage for drive control and the voltage for AC voltage burden exceeds system voltage Vdc. That is, the system voltage Vdc lacks the AC voltage share, and the inverters 20 and 30 normally drive and control the motor generators MG1 and MG2, respectively, while generating the commercial AC voltage Vac composed of AC220V between the neutral points N1 and N2. It cannot be generated.

  On the other hand, referring to FIG. 6, when field weakening control of motor generator MG1 is performed, the electromotive force of motor generator MG1 is reduced, so that inverter 20 can maintain the rotational speed of motor generator MG1 at a lower control voltage ( However, torque decreases.) As a result, a voltage margin is generated in motor generator MG1, and this margin is used as an AC voltage burden in motor generator MG1.

  Therefore, in power output device 100, even if commercial AC voltage Vac is high, in each of motor generators MG1 and MG2, the sum of the voltage for drive control and the voltage for AC voltage sharing is calculated as system voltage Vdc. The following can be suppressed. In other words, the system voltage Vdc can secure an AC voltage share, and the inverters 20 and 30 drive and control the motor generators MG1 and MG2, respectively, while commercializing a high voltage of 220V AC between the neutral points N1 and N2. An alternating voltage Vac can be generated.

  FIG. 7 is a voltage waveform diagram of motor generator MG1 when commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 is AC100V. In FIG. 7, only the U-phase voltage in motor generator MG1 is representatively shown.

  Referring to FIG. 7, curve Vu1 represents the U-phase voltage of motor generator MG1, and curve Vac1 represents the neutral point potential of motor generator MG1. Curves k3 and k4 show the envelope of the phase voltage of motor generator MG1. The U-phase voltage indicated by curve Vu1 is obtained by adding the U-phase control voltage for driving and controlling motor generator MG1 to the neutral point potential of motor generator MG1 indicated by curve Vac1.

  As shown in the figure, since commercial AC voltage Vdc is 100 VAC, the neutral point potential amplitude of motor generator MG1 indicated by curve Vac1 is not so large, and the maximum value of U-phase voltage is equal to system voltage Vdc. It becomes as follows.

  FIG. 8 is a voltage waveform diagram of motor generator MG1 when commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 is AC 220V. In FIG. 8, only the U-phase voltage in motor generator MG1 is representatively shown. AC220V is an example indicating that the commercial AC voltage Vac is a high voltage, and the commercial AC voltage Vac is not limited to AC220V.

  Referring to FIG. 8, since commercial AC voltage Vdc is a high voltage of AC 220 V, the amplitude of neutral point potential of motor generator MG1 indicated by curve Vac1 is larger than that when commercial AC voltage V dc is AC 100 V. . However, since the U-phase control voltage for driving and controlling motor generator MG1 is suppressed by the field weakening control of motor generator MG1, the amplitude of the fluctuation corresponding to the drive control amount of the U-phase voltage indicated by curve Vu1 is small. As a result, the maximum value of the U-phase voltage is equal to or lower than system voltage Vdc.

  As described above, according to the first embodiment, motive power output device 100 generates commercial AC voltage Vac between neutral points N1 and N2 of motor generators MG1 and MG2 and outputs it from connector 50 to an external AC load. can do.

  Power output device 100 weakens motor generator MG1 and performs field control when there is a request to output commercial AC voltage Vac having a voltage level that cannot be compensated by system voltage Vdc. A commercial AC voltage Vac can be generated.

  Further, in this power output device 100, only the motor generator MG1 that operates as a generator driven by the engine and operates as an electric motor that can start the engine is subjected to field-weakening control, and the vehicle on which this power output device 100 is mounted. Since field-weakening control of motor generator MG2 that operates as an electric motor that drives the drive wheels is not performed, desired commercial AC voltage Vac can be generated without affecting the traveling function of the vehicle.

  In power output device 100, commercial AC voltage Vac is generated using inverters 20 and 30 that drive motor generators MG1 and MG2, respectively, so that a dedicated inverter for obtaining commercial AC voltage Vac is not required. .

  In the above description, only the motor generator MG1 is subjected to field weakening control, but both the motor generators MG1 and MG2 may be subjected to field weakening control. In this case, the generated torque of motor generator MG2 is reduced by field weakening control of motor generator MG2, but from the viewpoint of efficiency, it is preferable that both motor generators MG1 and MG2 bear an average. Further, depending on the operating state of power output device 100, only motor generator MG2 may be subjected to field weakening control.

[Embodiment 2]
In the first embodiment, it is possible to generate a high-voltage commercial AC voltage Vac by performing field-weakening control on the motor generator. However, in the second embodiment, when there is a request for output of the high-voltage commercial AC voltage Vac, Increase the system voltage itself.

  The overall configuration of the power output apparatus according to Embodiment 2 is the same as that of power output apparatus 100 according to Embodiment 1 shown in FIG.

  In the second embodiment, in response to the output request for high-voltage commercial AC voltage Vac, control device 60 raises target value Vdc_com of system voltage Vdc from first voltage level Vdc1 to second voltage level Vdc2. . Similar to the first embodiment, control device 60 sets torque command values and motor speeds of motor generators MG1 and MG2, the battery voltage of battery B, and the voltage of power supply line PL2 (actual value of system voltage Vdc). Based on this, a control signal PWC for driving boost converter 10 is generated, and the generated control signal PWC is output to boost converter 10. That is, control device 60 performs feedback control of system voltage Vdc, and generates control signal PWC for driving boost converter 10 so that system voltage Vdc becomes target value Vdc_com including second voltage level Vdc2.

  Then, boost converter 10 stores the DC voltage from battery B as a magnetic field energy in reactor L1 by accumulating a current flowing according to the switching operation of npn transistor Q2 as a magnetic field energy based on control signal PWC from control device 60. The voltage is boosted to the level Vdc2, and the boosted voltage is output to the power supply line PL2 via the diode D1 in synchronization with the timing when the npn transistor Q2 is turned off.

  FIG. 9 is a diagram for explaining the concept of voltage distribution of motor generators MG1 and MG2 in the second embodiment when commercial AC voltage Vac generated between neutral points N1 and N2 of motor generators MG1 and MG2 is AC 220V. It is. Referring to FIG. 9, since commercial AC voltage Vac is a high voltage of AC 220V, the AC voltage share (hatched portion in the figure) in each of motor generators MG1 and MG2 is greater than that of AC 100V shown in FIG. Is also big. Therefore, in each of motor generators MG1 and MG2, the sum of the voltage for drive control and the voltage for AC voltage exceeds voltage level Vdc1 of system voltage Vdc, which was sufficient when commercial AC voltage Vac is AC100V. .

  However, in the second embodiment, control device 60 controls boost converter 10 such that system voltage Vdc rises from voltage level Vdc1 to voltage level Vdc2, and boost converter 10 raises system voltage Vdc to voltage level Vdc2. Control. Therefore, even if commercial AC voltage Vac is high, an AC voltage share can be secured, and inverters 20 and 30 drive and control motor generators MG1 and MG2, respectively, between neutral points N1 and N2. A high-voltage commercial AC voltage Vac composed of AC 220V can be generated.

  As described above, according to the second embodiment, when the output request of the high-voltage commercial AC voltage Vac is made, the system voltage Vdc is raised from the voltage level Vdc1 to the voltage level Vdc2. Vac can be generated.

  As a combination of the above-described first and second embodiments, when there is an output request for commercial AC voltage Vac having a voltage level that cannot be supplemented by system voltage Vdc having voltage level Vdc1, first, motor generator MG1 is weakened. When field control is performed and there is an output request for a commercial AC voltage Vac having a voltage level that cannot be compensated by the system voltage Vdc having a voltage level Vdc higher than the voltage level Vdc1, the system voltage Vdc is changed from the voltage level Vdc1 to the voltage level Vdcch. You may make it raise to high voltage level Vdc2. Thereby, it is possible to flexibly cope with a wide range of AC voltage output, and it is possible to suppress a reduction in efficiency of motor generator MG1 due to field weakening control within a certain range.

  In this case, as described above, field weakening control may be performed by both motor generators MG1 and MG2 from the viewpoint of efficiency, or only motor generator MG2 may be subjected to field weakening control.

  FIG. 10 is a schematic block diagram when the power output apparatus 100 according to the present invention is applied to a hybrid vehicle. Referring to FIG. 10, motor generator MG <b> 1 is connected to engine 70, starts engine 70, and generates power by the rotational force from engine 70. Motor generator MG2 is connected to drive wheel 80, drives drive wheel 80, and generates electric power during regenerative braking of the hybrid vehicle.

  The connector 50 is connected to an outlet 55 of an AC load 90 that is an external AC load, and the power output apparatus 100 supplies the commercial AC voltage Vac to the AC load 90 via the connector 50 and the outlet 55. Thereby, AC load 90 can operate by receiving supply of commercial AC voltage Vac from power output device 100.

  Thus, this hybrid vehicle equipped with the power output apparatus 100 can be used as an AC 100V power source, and can also be used as a commercial AC power source of higher voltage such as AC 220V. Since this hybrid vehicle does not include a dedicated inverter for generating the commercial AC voltage Vac, the hybrid vehicle has added value as a commercial AC power source while realizing reduction in size, weight, and cost of the vehicle.

  In the above description, the power output device 100 is described as being mounted on a hybrid vehicle. However, in the present invention, the power output device 100 is not limited to this, and the power output device 100 may be used in an electric vehicle and a fuel cell vehicle. It may be mounted. The present invention is generally applicable to those using two motor generators. When power output device 100 is mounted on an electric vehicle and a fuel cell vehicle, motor generators MG1 and MG2 are coupled to drive wheels of the electric vehicle and the fuel cell vehicle.

  In the above, motor generator MG1 constitutes a “first motor generator”, and motor generator MG2 constitutes a “second motor generator”. The inverter 20 constitutes a “first inverter”, and the inverter 30 constitutes a “second inverter”. Further, the battery B constitutes a “DC power supply”.

  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 a schematic block diagram of a power output apparatus according to Embodiment 1 of the present invention. FIG. 2 is a diagram for explaining a current that flows through a motor generator in order to generate a commercial AC voltage between neutral points of the motor generator shown in FIG. 1. It is a wave form diagram of the sum total of duty and commercial AC voltage. It is a figure for demonstrating the concept of the voltage distribution in a motor generator when the commercial alternating voltage generated between the neutral points of a motor generator is AC100V. It is the 1st figure for demonstrating the concept of the voltage distribution in a motor generator when the commercial alternating voltage generated between the neutral points of a motor generator is AC220V. It is the 2nd figure for demonstrating the concept of the voltage distribution in a motor generator when the commercial alternating voltage generated between the neutral points of a motor generator is AC220V. It is a voltage waveform diagram of motor generator MG1 when the commercial AC voltage generated between the neutral points of the motor generator is AC 100V. It is a voltage waveform diagram of motor generator MG1 when the commercial AC voltage generated between the neutral points of the motor generator is AC 220V. It is a figure for demonstrating the concept of the voltage distribution of the motor generator in Embodiment 2 when the commercial alternating voltage generated between the neutral points of a motor generator is AC220V. It is a schematic block diagram at the time of applying the power output device by this invention to a hybrid vehicle.

Explanation of symbols

  10 boost converter, 20, 30 inverter, 21, 31 U-phase arm, 22, 32 V-phase arm, 23, 33 W-phase arm, 40 AC port, 50 connector, 55 outlet, 60 control device, 70 engine, 80 drive wheel , 90 AC load, 100 power output device, B battery, C1, C2 capacitor, PL1, PL2 power line, SL ground line, L1 reactor, Q1, Q2, Q11-Q16, Q21-Q26 npn transistors, D1, D2, D11 to D16, D21 to D26 Diode, UL1, UL2 U phase line, VL1, VL2 V phase line, WL1, WL2 W phase line, MG1, MG2 motor generator, N1, N2 neutral point, ACL1, ACL2 AC output line.

Claims (7)

First and second motor generators;
First and second inverters respectively connected to the first and second motor generators and receiving a system voltage from a voltage supply line;
The first and second motor generators are driven using the system voltage, and the first and second motor generators generate an AC voltage between neutral points of the first and second motor generators. A control device for controlling the operation of the inverter,
When there is an AC voltage output request having a voltage level that cannot be generated by the system voltage, the control device performs field-weakening control on one or both of the first and second motor generators. A power output device that controls the operation of the first and / or second inverter. The first motor generator is connected to an internal combustion engine of a vehicle,
The second motor generator is coupled to drive wheels of the vehicle,
When there is an AC voltage output request having a voltage level that cannot be generated by the system voltage, the control device controls the operation of the first inverter so as to perform the field-weakening control on the first motor generator. The power output apparatus according to claim 1. First and second motor generators;
DC power supply,
A boost converter that boosts a DC voltage output from the DC power source to a system voltage;
First and second inverters respectively connected to the first and second motor generators and receiving the system voltage from the boost converter;
The operation of the boost converter is controlled, the first and second motor generators are driven using the system voltage, and an AC voltage is applied between neutral points of the first and second motor generators. A control device for controlling the operation of the first and second inverters to generate,
The power output device, wherein when there is an AC voltage output request having a voltage level that cannot be generated by the system voltage, the control device controls the operation of the boost converter so as to increase the system voltage. First and second motor generators;
DC power supply,
A boost converter that boosts a DC voltage output from the DC power source to a system voltage;
First and second inverters respectively connected to the first and second motor generators and receiving the system voltage from the boost converter;
The operation of the boost converter is controlled, the first and second motor generators are driven using the system voltage, and an AC voltage is applied between neutral points of the first and second motor generators. A control device for controlling the operation of the first and second inverters to generate,
The controller is
When there is a request to output an AC voltage having a voltage level that cannot be generated by the system voltage having the first voltage level, field weakening control is performed on one or both of the first and second motor generators. Controlling the operation of the first and / or second inverter;
Controls the operation of the boost converter so as to increase the system voltage when there is an output request for an AC voltage having a voltage level that cannot be generated even by a system voltage having a second voltage level higher than the first voltage level. A power output device. The first motor generator is connected to an internal combustion engine of a vehicle,
The second motor generator is coupled to drive wheels of the vehicle,
When there is a request to output an AC voltage having a voltage level that cannot be generated by the system voltage having the first voltage level, the control device performs the field-weakening control on the first motor generator. The power output apparatus of Claim 4 which controls operation | movement of 1 inverter. A power output device according to any one of claims 1 to 5, comprising:
The power output device drives a drive wheel and supplies the generated AC voltage to an external AC load. An internal combustion engine,
A first motor generator included in the power output device is coupled to the internal combustion engine;
A second motor generator included in the power output device is coupled to the drive wheel;
The vehicle according to claim 6, wherein the second motor generator drives the drive wheels.

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