JP2018207584A - Power supply system for electric vehicle - Google Patents

Abstract

To utilize an inverter that is mounted in an electric vehicle, even when converting DC power of a battery into AC power and supplying the AC power as a domestic power supply in the case of emergency.SOLUTION: In a travel mode, target current values Id and Iq of a (d) axis and a (q) axis of an electric motor M that are identified from a "MAP for travel" by a target current value calculation part 31 are used to perform a turning-on/turning-off operation of an inverter INV in a pattern that a torque corresponding to a torque command value τ from a vehicle integrated controller VCM is outputted to the electric motor M. In a V-to-V charge mode, target current value Id and Iq (wherein Iq=0) of the (d) axis and the (q) axis of the electric motor M that are identified from a "MAP for V-to-V" by the target current value calculation part 31 are used to perform a turning-on/turning-off operation of the inverter INV in a pattern that single-phase AC power in a frequency (50 Hz) of a commercial power supply indicated by a pulse signal from a power supply frequency pulse output part 39 is outputted from a power supply cable 5.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a power supply system for an electric vehicle.

  Conventionally, it has been proposed to convert direct current power of a battery mounted on an electric vehicle (EV) into alternating current by an inverter and supply it as household power supply in an emergency (for example, Patent Document 1).

JP-A-11-178234

  An electric vehicle is equipped with an inverter that converts the DC power of the battery into AC and supplies it to the propulsion motor. This inverter is used to supply the DC power of the battery as a household power source in an emergency. Whether to use for conversion is not mentioned in the above-mentioned conventional proposal.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to convert an inverter mounted on an electric vehicle such as an electric vehicle (EV) or a hybrid vehicle (HEV) by converting DC power of a battery into AC. It is to be able to use it when supplying it outside the electric vehicle.

In order to achieve the above object, a power supply system for an electric vehicle according to one aspect of the present invention includes:
A three-phase output inverter that converts the DC power of the battery of the electric vehicle into a three-phase AC to be supplied to the propulsion motor by a switching operation;
An output connector for outputting a single-phase AC power appearing between a one-phase output of the three-phase output inverter and a neutral point of the propulsion motor to the outside of the electric vehicle;
A controller that switches the three-phase output inverter in a pattern in which single-phase AC power appears between the one-phase output and the neutral point when the single-phase AC power is output from the output connector;
Is provided.

  According to the present invention, the inverter mounted on the electric vehicle can also be used when the DC power of the battery is converted into AC and supplied to the outside of the electric vehicle.

It is a block diagram which shows schematic structure of the drive control apparatus of the alternating current motor which concerns on 1st Embodiment of this invention. It is a block diagram which shows the specific structure of the motor controller of FIG. It is a block diagram which shows the outline | summary of the calculation process of the d-axis and q-axis target current value of an electric motor performed when the target current value calculation part of FIG. 2 is driving mode. It is a block diagram which shows the outline | summary of the calculation process of the d-axis and q-axis target current value of an electric motor performed when the target current value calculation part of FIG. 2 is a VtoV charge mode. It is explanatory drawing which shows the matrix of the voltage equation used for the voltage conversion part of FIG. 2 converting the electric current target value of d axis | shaft and q axis | shaft of an electric motor into a command voltage. It is a flowchart which shows the sequence of the mode determination process which the motor controller of FIG. 1 performs. It is a block diagram which shows the outline | summary of the calculation process of each electric current target value of d axis | shaft and q axis | shaft of an electric motor performed when the electric current target value calculation part of FIG. 2 is a commercial power output mode.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a power supply system for an electric vehicle according to an embodiment of the present invention. A power supply system 1 according to this embodiment shown in FIG. 1 is used for an electric vehicle such as an electric vehicle (EV) or a hybrid vehicle (HEV) that uses an electric motor M (corresponding to a propulsion motor in claims) as power or power assist. Installed. The power supply system 1 includes an inverter INV, a motor controller 3 and a power feeding cable 5.

  The inverter INV (corresponding to the three-phase output inverter in the claims) converts DC power (for example, DC 400V) of a battery (not shown) such as a lithium ion battery mounted on the electric vehicle into three-phase AC. Output to the electric motor M. This inverter INV has power semiconductor switching elements Q1 to Q3 and Q4 to Q6 on the upper arm and the lower arm of each phase of UVW.

  In the present embodiment, each of the power semiconductor switching elements Q1 to Q6 is configured by an IGBT (Insulated Gate Bipolar Transistor).

  The inverter INV is a single-phase alternating current that appears between the output of one phase of the output of the electric motor M for each UVW phase and the neutral point N of the three-phase stator coils Lu, Lv, Lw of the electric motor M. Electric power is output from the outlet 7 (corresponding to the output connector in the claims) of the feeding cable 5 to the outside of the electric vehicle.

  The outlet 7 can be connected to a plug (not shown) of a power cable of a supply source of single-phase AC power (for example, household appliances or household storage batteries). In this embodiment, in order to normally charge a battery (not shown) of another electric vehicle V (equivalent to a supply destination and a plug-in hybrid vehicle supplying single-phase AC power in the claims) to the outlet 7, It is assumed that a plug 13 of the charging cable 11 (a single-phase AC power output destination connector and a charging power connector in the claims) is connected.

  The motor controller 3 (corresponding to the controller in the claims) is input from the vehicle integrated controller VCM in a travel mode in which DC power of a battery (not shown) is converted into three-phase AC by the inverter INV and supplied to the electric motor M. The power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on and off in a pattern that causes the electric motor M to output a torque corresponding to the torque command value.

  Further, the motor controller 3 converts the DC power of a battery (not shown) into a single-phase AC by the inverter INV and supplies it from the power supply cable 5 to the charging cable 11 of the other electric vehicle V. In the mode, the power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on / off in a pattern in which single-phase AC power having the same frequency as that of the commercial power supply is output from the power supply cable 5.

  The vehicle integrated controller VCM calculates the torque of the electric motor M according to the driver's accelerator operation, and outputs a torque command value corresponding to the calculated torque to the motor controller 3. The vehicle integrated controller VCM also outputs a voltage value of a battery (not shown) to the motor controller 3.

  Furthermore, when the plug 13 of the charging cable 11 of the other electric vehicle V is connected to the outlet 7 of the power supply cable 5, the vehicle integrated controller VCM communicates with the vehicle integrated controller (not shown) of the other electric vehicle V. Information is acquired from another electric vehicle V by vehicle-to-vehicle communication.

  The information acquired by the vehicle integrated controller VCM from the other electric vehicle V is, for example, a rated charging current when charging a battery with single-phase AC power received from the charging cable 11 by a charger (not shown) of the other electric vehicle V. Contains value information. Information on the other electric vehicle V acquired by the vehicle integrated controller VCM is output to the motor controller 3.

  As shown in FIG. 2, the motor controller 3 includes a current target value calculation unit 31, a current-voltage conversion unit 33, a dq axis-three-phase converter 35, and a rotation speed output unit 37. These can be configured individually or entirely, or can be configured integrally by discrete circuits, IC chips (including those with built-in memory), or the like. Of course, it is also possible to adopt a configuration in which the functions of the units 31 to 37 are realized by the computer executing the program.

  A pulse signal is input from the rotation speed output unit 37 to the current target value calculation unit 31. The rotation speed output unit 37 includes a power supply frequency pulse output unit 39 and a switching unit 41.

  The power supply frequency pulse output unit 39 outputs a pulse signal having the same frequency as the frequency of the commercial power supply (corresponding to the predetermined frequency in the claims) in the region where the other electric vehicle V is destined (whether domestic or overseas) at the time of manufacture. Output. In this embodiment, it is assumed that the power frequency pulse output unit 39 outputs a single-phase 50 Hz pulse signal in the eastern Japan region.

  The switching unit 41 outputs the pulse signal output to the current target value calculation unit 31 for the driving mode, the pulse signal having a frequency corresponding to the rotational speed of the electric motor M output by the rotational speed sensor 43, and the VtoV charging mode. The power frequency pulse output unit 39 switches between the commercial power source frequency pulse signal.

  Then, the current target value calculation unit 31 uses the d-axis and q-axis current target values Id and Iq of the electric motor M corresponding to the torque command value of the electric motor M from the vehicle integrated controller VCM as the mode of the electric vehicle ( According to the travel mode and the VtoV charge mode), the “travel MAP” and the “VtoV MAP” shown in FIG.

  Here, “travel MAP” is used to calculate the current target values Id and Iq of the d-axis and the q-axis of the electric motor M in the travel mode. The “travel MAP” is a table in which a torque command value input from the vehicle integrated controller VCM to the motor controller 3 and a target rotational speed of the electric motor M corresponding to the torque command value are associated with each other.

  On the other hand, “MAP for VtoV” is used to calculate the current target values Id and Iq of the d-axis and q-axis of the electric motor M in the VtoV charging mode. This “VtoV MAP” is the frequency of the commercial power supply indicated by the pulse signal input from the power supply frequency pulse output unit 39 to the current target value calculation unit 31 in the VtoV charging mode, and the current target of the electric motor M corresponding thereto. It is a table that associates values.

  When the power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on / off in a pattern in which single-phase AC power is output from the power supply cable 5, the q-axis current target value Iq that is a torque current component is other than “0”. If the value is, the electric motor M rotates and the electric vehicle moves.

  For this reason, in the VtoV charging mode, only the d-axis current target value Id that is the excitation current component is calculated using the “VtoV MAP”, and the q-axis current target value Iq that is the torque current component. Is uniformly “0”. Therefore, “VtoV MAP” is the frequency of the commercial power source indicated by the pulse signal input from the power source frequency pulse output unit 39 to the current target value calculation unit 31 and the d-axis current target value Id of the electric motor M corresponding thereto. As a table in which

  When the electric vehicle is in the travel mode, the current target value calculation unit 31 calculates the target rotational speed of the electric motor M corresponding to the torque command value from the vehicle integrated controller VCM as shown in the block diagram of FIG. And “MAP for travel”.

  Furthermore, the current target value calculation unit 31 is an electric motor indicated by the target rotational speed of the electric motor M specified by “traveling MAP” and the driving mode pulse signal input from the switching unit 41 to the current target value calculation unit 31. Based on the difference from the rotation speed of the motor M, the d-axis and q-axis current target values Id and Iq of the electric motor M are calculated by a conventionally known method.

  On the other hand, when the electric vehicle is in the VtoV charging mode, the current target value calculation unit 31 has a commercial power frequency (indicated by the pulse signal from the power frequency pulse output unit 39 as shown in the block diagram of FIG. The d-axis target current value Id of the electric motor M corresponding to 50 Hz) is specified from “MAP for VtoV”.

  Note that a plurality of “VtoV MAPs” of the current target value calculation unit 31 are prepared for each current value of the single-phase AC power output from the power supply cable 5. For this reason, when the electric vehicle is in the VtoV charging mode, the current target value calculation unit 31 uses “MAP for VtoV” corresponding to the rated charging current value of the other electric vehicle V input from the vehicle integrated controller VCM. The d-axis target current value Id of the electric motor M is specified.

  Furthermore, the current target value calculation unit 31 determines whether the electric power supply cable 5 is based on the d-axis current target value Id of the electric motor M specified by “VtoV MAP” and the voltage value of the battery from the vehicle integrated controller VCM. The d-axis target current value Id is calculated by a conventionally known method so that the current value of the output 50 Hz single-phase AC power becomes the rated charging current value of the other electric vehicle V input from the vehicle integrated controller VCM. (Q-axis target current value Iq is “0”).

  The current-voltage conversion unit 33 shown in FIG. 2 uses the d-axis and q-axis currents of the electric motor M calculated by the current target value calculation unit 31 with reference to the frequency of the pulse signal output from the rotation speed output unit 37. The target values Id and Iq are converted into the command voltages vd and vq for the d axis and the q axis, respectively.

  Specifically, the voltage equation of the electric motor M can be expressed by the determinant described in FIG. In this determinant, R is the winding resistance of the stator coil of the electric motor M, Ld and Lq are the self-inductances of the d-axis and q-axis of the electric motor M, and ωΦa is the stator by the permanent magnet of the rotor of the electric motor M. This is an induced voltage generated only on the q-axis side by the interlinkage magnetic flux of the coil.

  These pieces of information are acquired in advance and set in the motor controller 3. Then, if the rotation speed of the electric motor M and the current target values Id and Iq of the d-axis and q-axis are substituted into the voltage equation described above, each of the d-axis and q-axis of the electric motor M corresponding to the torque command value τ. The current target value and the d-axis current target value Id of the electric motor M corresponding to the frequency (50 Hz) of the commercial power supply can be converted into command voltages vd and vq (peak values thereof).

  The dq-axis to three-phase converter 35 includes a command voltage vd for the d-axis and q-axis of the electric motor M converted from the current target values Id and Iq for the d-axis and q-axis of the electric motor M by the current-voltage converter 33. , Vq are converted into UVW three-phase voltages Vu, Vv, Vw and output to inverter INV.

  The motor controller 3 in which the units 31 to 37 perform the operations described above determines whether the power supply system 1 is operated in the running mode or the VtoV charging mode when an ignition switch (not shown) is turned on. To do. Hereinafter, the procedure of the mode determination process performed by the motor controller 3 when the ignition switch is turned on will be described with reference to the flowchart of FIG.

  First, after the ignition switch is turned on (step S1), the motor controller 3 checks whether or not the electric vehicle is in the VtoV charging mode (step S3). Whether or not it is in the VtoV charging mode can be confirmed, for example, by whether or not the plug 13 of the charging cable 11 of another electric vehicle V is connected to the outlet 7 of the power feeding cable 5.

  When the electric vehicle is not in the VtoV charging mode (NO in step S3), the motor controller 3 shifts to the running mode sequence (step S5) and ends the mode determination processing sequence.

  On the other hand, when the electric vehicle is in the VtoV charging mode (NO in step S3), the motor controller 3 uses the information on the rated charging current value acquired by the vehicle-to-vehicle communication with the vehicle integrated controller of the other electric vehicle V. Read from the integrated controller VCM (step S7). Then, the motor controller 3 switches the “VtoV MAP” used to specify the d-axis current target value Id of the electric motor M to one corresponding to the read rated charging current value of the other electric vehicle V.

  Further, the motor controller 3 causes the switching unit 41 to switch the pulse signal output from the rotation speed output unit 37 from the pulse signal for the running mode to the pulse signal for the VtoV charging mode (step S11).

  Then, the motor controller 3 calculates the electric motor from the d-axis target current value Id of the electric motor M specified by 31 using “VtoV MAP” and the q-axis target current value Iq set to “0”. M is converted into UVW three-phase voltage Vu, Vv, Vw and output to inverter INV.

  Thus, the power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on / off in a pattern in which 50 Hz single-phase AC power is output from the power supply cable 5, and 50 Hz single-phase AC power is output from the power supply cable 5. That is, the charging of the battery of another electric vehicle V in which the charging cable 11 is connected to the power feeding cable 5 is started (step S13).

  Subsequently, the motor controller 3 shifts to the sequence of the VtoV charging mode (step S15), and ends the sequence of the mode determination process.

  According to the power supply system 1 of the present embodiment described above, when the electric vehicle is in the travel mode, the currents of the d-axis and q-axis of the electric motor M specified by the current target value calculation unit 31 from “travel MAP”. Using the target values Id and Iq, the power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on and off in a pattern that causes the electric motor M to output a torque corresponding to the torque command value τ from the vehicle integrated controller VCM. did.

  When the electric vehicle is in the VtoV charging mode, the current target value calculation unit 31 sets the current target values Id and Iq of the d-axis and q-axis of the electric motor M specified from “MAP for VtoV” (where Iq = 0). Is used to output the single-phase AC power of the commercial power supply frequency (50 Hz) indicated by the pulse signal from the power supply frequency pulse output unit 39 from the power supply cable 5, and the power semiconductor switching elements Q1 to Q6 of the inverter INV are output. It was made to operate on and off.

  Therefore, the inverter INV mounted to convert the DC power of the battery into the three-phase AC power to the electric motor M of the electric vehicle is supplied, and the DC power of the battery is charged to charge the battery of the other electric vehicle V. It can also be used when it is converted into a single-phase alternating current of 50 Hz and output from the feeding cable 5.

  The current target value calculation unit 31 specifies only the d-axis current target value Id that is the excitation current component in the VtoV charge mode, and the q-axis current target of the torque current component. Since the value Iq is uniformly 0, it is possible to reliably prevent the electric motor M from rotating due to the rotation of the electric motor M in the VtoV charging mode.

  In the present embodiment, the switching unit 41 outputs the pulse signal output from the rotation speed output unit 37 when the plug 13 of the charging cable 11 of another electric vehicle V is connected to the outlet 7 of the power supply cable 5 as a trigger. The pulse signal for the driving mode is switched to the pulse signal for the VtoV charging mode.

  However, for example, when the driver performs a switching instruction operation while the electric vehicle is stopped, the pulse signal output by the rotation speed output unit 37 is changed from the pulse signal for the driving mode to the VtoV charging mode by the switching unit 41. You may make it switch to a pulse signal.

  Moreover, in this embodiment, the plug 13 of the charging cable 11 of the other electric vehicle V is connected to the outlet 7 of the power supply cable 5, and other single-phase AC power for charging the battery of the other electric vehicle V is used. The case of outputting from the power feeding cable 5 at the rated charging current value of the charger of the electric vehicle V has been described. However, a home power supply may be output from the power supply cable 5 instead of the commercial power supply.

  In that case, a plug (not shown) on the home side is connected to the outlet 7 of the power supply cable 5, and the single-phase AC power of 50 Hz, which is the same as that of the commercial power supply, is used as a power source via the power supply cable 5. Will be supplied.

  Here, when the single-phase AC power supplied through the power supply cable 5 is used as a commercial power source, if the load of the home appliance is high, the current of the single-phase AC power is insufficient and the output voltage from the power supply cable 5 May be reduced.

  Therefore, “VtoV MAP” used to calculate the current target values Id and Iq of the d-axis and q-axis of the electric motor M when the household power supply is output from the power supply cable 5 instead of the commercial power supply, A plurality of current target value calculation units 31 are prepared for each output voltage from the power supply cable 5.

  Then, as shown in FIG. 7, in the current target value calculation unit 31, using the “VtoV MAP” corresponding to the output voltage of the power supply cable 5 monitored by the vehicle integrated controller VCM or the motor controller 3, the electric motor M D-axis current target value Id is specified.

  Using the d-axis current target value Id of the electric motor M specified in this way and the q-axis current target value Iq set to “0”, the VtoV charging mode of charging the battery of another electric vehicle V is performed. Similarly to the time, the power semiconductor switching elements Q1 to Q6 of the inverter INV are turned on and off to output 50-Hz single-phase AC power from the power supply cable 5.

  As a result, 50 Hz single-phase AC power can be stably output from the power supply cable 5 in a state in which a necessary current value is maintained in accordance with a change in the load of a household device connected to the power supply cable 5.

  The present invention can be widely applied to a power supply system for an electric vehicle such as an electric vehicle (EV) or a hybrid vehicle (HEV).

  The present invention can be used in a power supply system of an electric vehicle.

1 Power supply system 3 Motor controller (controller)
5 Power supply cable 7 Outlet (output connector)
11 Charging cable 13 Plug (Single-phase AC power output destination connector, charging power connector)
31 Current Target Value Calculation Unit 33 Current / Voltage Conversion Unit 35 Three-Phase Converter 37 Rotational Speed Output Unit 39 Power Frequency Pulse Output Unit 41 Switching Unit 43 Rotational Speed Sensor INV Inverter (Three-phase Output Inverter)
Id Current target value Id, Iq Current target value Iq Current target value Lu, Lv, Lw Stator coil M Electric motor (propulsion motor)
N Neutral point Q1-Q6 Power semiconductor switching element V Electric vehicle (supplier supplying single-phase AC power, plug-in hybrid vehicle)
VCM Vehicle integrated controller Vu, Vv, Vw Electric motor phase voltage

Claims (8)

A three-phase output inverter (INV) that converts the DC power of the battery of the electric vehicle into a three-phase AC to be supplied to the propulsion motor (M) by a switching operation;
The single-phase AC power that appears between the output of each phase of the three-phase output inverter (INV) and the neutral point (N) of the propulsion motor (M) is supplied to the outside of the electric vehicle. An output connector (7) for outputting to
When the single-phase AC power is output from the output connector (7), the three-phase output inverter (INV) is configured so that the single-phase AC power appears between the one-phase output and the neutral point (N). A controller (3) for switching;
An electric vehicle power supply system (1) comprising:   The controller (3) determines the torque corresponding to the torque command value of the propulsion motor (M) determined based on the voltage of the battery and the rotation frequency corresponding to the rotation speed of the propulsion motor (M). The power system (1) for an electric vehicle according to claim 1, wherein the three-phase output inverter (INV) is switched in a pattern in which the propulsion motor (M) is output.   The controller (3) switches the three-phase output inverter (INV) in a pattern in which a torque to be output to the propulsion motor (M) determined based on a predetermined frequency instead of the rotation frequency is zero. Item 3. A power system (1) for an electric vehicle according to Item 2.   The power system (1) for an electric vehicle according to claim 3, wherein the predetermined frequency is a commercial power frequency in a destination area of the electric vehicle.   The power system (1) for an electric vehicle according to claim 3, wherein the predetermined frequency is a required frequency of a supply destination (V) that supplies single-phase AC power by the output connector (7).   The frequency used to determine the switching pattern of the three-phase output inverter (INV) is the rotation frequency corresponding to the rotation speed detected by the rotation sensor (43) of the propulsion motor (M) and the predetermined frequency. The power supply system (1) for an electric vehicle according to claim 3, 4 or 5, further comprising a switching unit (41) for switching between the two.   The switching unit (41) determines a switching pattern of the three-phase output inverter (INV) when the output connector (7) is connected to the output connector (13) of the single-phase AC power. The power supply system (1) for an electric vehicle according to claim 6, wherein the frequency to be used is switched from the rotational frequency to the predetermined frequency.   The power system (1) for an electric vehicle according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the output connector is connectable to a charging power connector (13) of a plug-in hybrid vehicle (V). .

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