JP2009065808A - Electric vehicle charging device and control method - Google Patents

Abstract

By controlling the rotor stop position to an optimum position, it is possible to prevent the rotor from rotating and the vehicle from moving, and also to prevent abnormal noise generation, temperature rise due to heat generation, and decrease in charging efficiency. An electric vehicle charging device and a control method are provided.
An electric vehicle charging device includes a secondary battery such as a nickel metal hydride battery, an inverter, a motor, a resolver that detects a rotation angle of the motor, and relays for charging. , A commercial power plug 20, a connection portion 21, a zero cross signal generator 18 for generating a zero cross signal from an AC signal of the commercial power, an inverter control circuit 16 and a vehicle control ECU 17. Further, the inverter 14 is connected to the connection point of the diodes 24 and 25 and the neutral point of the motor in the order of the commercial power plug 20 for connection with the commercial power source, the connection portion 21, and the charging relays 22 and 23.
[Selection] Figure 1

Description

  It has a secondary battery that can charge and discharge power, an inverter that drives the motor with the power of the secondary battery, and a connection that connects an external power supply to the neutral point of the motor, and uses the motor coil and inverter The present invention relates to an electric vehicle charging apparatus and a control method for charging a secondary battery from an external power source.

  An electric vehicle such as a hybrid vehicle having an engine or a fuel cell vehicle travels by driving a motor with electric power stored in a nickel hydride battery or an electric double layer capacitor as a secondary battery. In particular, an electric vehicle that does not have a power generation function cannot run when the amount of charge of the secondary battery is exhausted, and thus a charging device that charges the secondary battery is required. Here, since the charging device is not necessary when the electric vehicle is traveling, it may be fixedly installed at a certain point or may be mounted on the vehicle.

  When the charging device is fixedly installed, it is necessary to move the electric vehicle to the place and perform charging, and thus there is a disadvantage that charging cannot be performed at other places. On the other hand, when the charging device is mounted on the vehicle, there is a problem that the vehicle weight increases. In order to solve this problem, an apparatus that uses a motor coil as a reactor to suppress an increase in vehicle weight and controls a circuit element of an inverter that drives the motor to perform charging from a commercial power supply for home use. It has been proposed in the past.

  However, when a permanent magnet motor in which a permanent magnet is arranged in the rotor is used, if current is passed through an arbitrary coil of the motor, torque that rotates the rotor may be generated depending on the magnetic pole position of the permanent magnet. When the rotor is rotated by this torque, there is a problem that the vehicle may vibrate or abnormal noise may occur during charging.

  Therefore, an electric vehicle charging apparatus as shown in Patent Document 1 has two motors, two inverters for controlling the currents flowing in the coils of the respective motors, and neutral points of the two motors. The connection circuit for connecting the commercial power supply, the magnetic pole position sensor for detecting the magnetic pole position of the rotor, and the three-phase coil of the motor based on the detected magnetic pole position, or the torque for rotating the rotor among the three-phase coils is minimized. A coil selection means for selecting a one-phase or two-phase coil that generates a magnetic field to be generated, and a circuit element of the inverter is controlled in the selected coil so that a current is supplied from a commercial power source, and these coils are used as a boosting reactor. A control circuit for charging the secondary battery is included.

  By using the technique disclosed in Patent Document 1, when three phases of the motor are selected and equal currents are supplied, the generated magnetic fields cancel each other out to zero, and the rotation of the rotor can be prevented. In addition, when a one-phase or two-phase coil that minimizes the torque for rotating the rotor is selected from the three-phase coils of the motor and current is passed through the coils, the generated torque is small, so the frictional resistance of the vehicle The rotation of the rotor can be prevented.

JP-A-8-126121

  However, in the case of using the technique of Patent Document 1, the rotor position when the vehicle is stopped is various angles, and torque vibration caused by minute torque fluctuations due to charging depending on the stop position of the rotor, heat generation of the magnet, charging due to inductance variation Variations in efficiency occurred, causing abnormal noise, heat generation, and a decrease in charging efficiency.

  Therefore, according to the present invention, when the secondary battery is charged, the rotor stop position is controlled to the optimum position, thereby preventing the rotor from rotating and the vehicle from moving, generating abnormal noise, and increasing the temperature due to heat generation. An object of the present invention is to provide a charging device for an electric vehicle and a control method capable of preventing a decrease in charging efficiency and the like.

  In order to achieve the above object, a charging device for an electric vehicle according to the present invention includes a secondary battery, a motor including a stator and a rotor, an inverter that drives the motor by the power of the secondary battery, and an external device. In a charging device for an electric vehicle, which has a connecting portion for connecting a power source to a neutral point of the motor, and charges a secondary battery from an external power source using a motor coil and an inverter, charging is performed with or without charging. In addition, there is provided a motor control means for stopping the motor at a target rotor angle at which each of torque generated in the motor and magnet loss is minimized.

  In the charging device for an electric vehicle according to the present invention, the motor control means stops the motor at a target rotor angle when stopping the vehicle.

  In the charging device for an electric vehicle according to the present invention, the motor control means rotates the motor to the target rotor angle and stops it while the charging instruction is actually performed after the vehicle stops. It is characterized by.

  Furthermore, in the charging device for an electric vehicle according to the present invention, the target rotor angle is determined by the characteristics of the motor, and is a rotor angle at which each of the torque and magnet loss generated in the motor is minimized and the motor inductance is maximized. It is characterized by being.

  Further, in the electric vehicle charging device according to the present invention, the motor control means controls the inverter to position the rotor at a desired target rotor angle.

  Furthermore, in the electric vehicle charging apparatus according to the present invention, when the motor is concentrated winding, the target rotor angle is an angle at which the magnetic pole center coincides with the slot center.

  Furthermore, in the electric vehicle charging apparatus according to the present invention, when the motor is distributed winding, the target rotor angle is an angle at which the center of the magnet coincides with the center of the teeth between the in-phase slots.

  In addition, the control method for the charging device for an electric vehicle according to the present invention includes a secondary battery, a motor including a stator and a rotor, an inverter that drives the motor by the power of the secondary battery, and an external power source that is neutral to the motor. In a control method for a charging device for an electric vehicle, which has a connecting portion connected to a point and charges a secondary battery from an external power source using a motor coil and an inverter, in preparation for charging regardless of whether there is charging or not And a motor control step of stopping the motor at a target rotor angle at which each of torque generated in the motor and magnet loss is minimized.

  In the method for controlling the charging device for an electric vehicle according to the present invention, the motor control step is characterized by stopping the motor at a target rotor angle when the vehicle is stopped.

  Further, in the method for controlling the charging device for an electric vehicle according to the present invention, the motor control step rotates the motor to the target rotor angle while the vehicle is stopped and the charging instruction is actually performed after the charging instruction is issued. It is characterized by being stopped.

  Further, in the method for controlling the charging device for an electric vehicle according to the present invention, the target rotor angle is determined by the characteristics of the motor, the torque generated in the motor and the magnet loss are minimized, and the inductance of the motor is maximized. It is a rotor angle.

  By using the present invention, when the secondary battery is charged, the rotor stop position is controlled to the optimum position to prevent the rotor from rotating and the vehicle from moving, while generating abnormal noise and increasing the temperature due to heat generation. In addition, there is an effect that a reduction in charging efficiency and the like can be prevented.

  Hereinafter, the best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described with reference to the drawings.

  FIG. 1 shows the configuration of an electric vehicle charging device 1. The electric vehicle charging apparatus 1 includes a secondary battery 15 such as a nickel metal hydride battery or a lithium ion battery, main power relays 26 and 28, an inverter 14, a motor 10, and a resolver 13 that detects a rotation angle of the motor 10. Relays 22 and 23 for charging, commercial power plug 20, connection 21 thereof, zero cross signal generator 18 for generating a zero cross signal from an AC signal of the commercial power, inverter control circuit 16 and vehicle control ECU 17, have.

  The secondary battery 15 can supply high-voltage DC power, and main power relays 26 and 27 are provided between the secondary battery and the inverter 14. In addition, an inrush limiting resistor 52 and an inrush limiting relay 27 are connected in parallel to the main power supply relay 26.

  The inverter 14 has U-phase, V-phase, and W-phase arms, and includes a plurality of switching transistors 31 to 36, diodes 41 to 46, and a capacitor 51. In driving the motor, the inverter 14 turns on / off each transistor based on the control of the inverter control circuit 16, converts the DC output of the secondary battery into a three-phase AC output, and outputs the three-phase AC. Can be supplied to the motor 10.

  Further, the inverter 14 is provided with a charging unit which is a characteristic configuration of the present invention. The inverter 14 is connected to the neutral point of the W phase from the connection point of the diodes 24 and 25 in the order of the commercial power plug 20 for connection with the commercial power source, the connection portion 21, and the charging relay.

  Next, an outline of the operation from the start of the electric vehicle to the charging process will be described with reference to FIG. At the time of charging, the commercial power plug 20 is connected to an AC 100V outlet, for example. The inverter control circuit 16 turns on the low-potential-side main power supply relay 28 and turns on the inrush restriction relay 27 before turning on the high-potential-side main power supply relay 26 according to an instruction from the vehicle control ECU 17. "turn on. Thus, the inrush current is reduced by gradually supplying current to the capacitor 51, the high-potential side main power supply relay 26 is turned "on" and the inrush limit relay 27 is turned "off" after a predetermined time has elapsed. The secondary battery and the inverter are connected.

  The inverter control circuit 16 acquires signals from the zero-cross signal generator 18 and the current sensor 19 to check whether the commercial power supply state and the charging state of the secondary battery are normal. Next, the inverter control circuit 16 turns on the charging relays 22 and 23 to start charging.

  Here, the zero-cross signal generator 18 is a signal that switches between a high level and a low level every time the voltage of the AC commercial power from the commercial power plug 20 becomes 0 volts, and serves as a reference for the voltage phase of the AC commercial power. At the time of charging, the inverter control circuit 16 controls each transistor of the inverter based on this zero cross signal so that the phases of the voltage and current are aligned and the impulse is “1”. The current sensor 19 detects a current (IB) flowing through the secondary battery 15 and outputs the state of the secondary battery to the inverter control circuit 16.

  FIG. 6 is a time chart showing an inverter control signal of the charging device for an electric vehicle. The horizontal axis represents time, and the vertical axis represents commercial power from above, PWM1 signal and PWM2 signal by transistors 31 and 32, and zero cross signal. Is shown. Hereinafter, the operation of the inverter 14 during charging will be described using the transistors 31 and 32, the diodes 41 and 42, and the rectifying diodes 24 and 25 connected to the W-phase arm of FIG. 1 as an example.

  The inverter control circuit 16 in FIG. 1 determines whether the voltage at the neutral point of the motor 10 connected to the commercial power supply is positive or negative with reference to the zero cross signal. As shown in FIG. 6, when the voltage at the neutral point is “positive” (zero cross signal: high level), the transistor 32 is controlled to repeat “on” and “off” (PWM1 signal), The transistor 31 is turned “off”. When the transistor 32 is turned from “on” to “off” in this way, the voltage is boosted by the W-phase coil of the motor 10, current flows through the diodes 41 and 25, charges are accumulated in the capacitor 51, and the secondary battery 15 is charged. Charging is performed.

  Next, when the voltage at the neutral point is “negative”, the transistor 31 is controlled to repeat “on” and “off” (PWM 2 signal), and the transistor 32 is turned “off”. When the transistor 31 is turned from “on” to “off”, the voltage is boosted by the W-phase coil of the motor 10, current flows through the diodes 42 and 24, charges are accumulated in the capacitor 51, and the secondary battery 15 is charged. . The other V-phase and U-phase transistors 33 to 36 are charged by the same control. The inverter control circuit 16 compares the detection value IB of the current sensor 19 with the control target current value Iref, and also controls the charging current based on the detection value IB that is the charged current.

  FIG. 2 shows a part of the concentrated winding motor 10 having the stator 11 and the rotor 12, and FIG. 4 shows the motor characteristics of the concentrated winding motor 10 with respect to torque vibration, inductance, and magnet loss. The stator 11 in FIG. 2 repeats the W phase, V phase, V phase, U phase, U phase, and W phase clockwise from the left, and the rotor 12 has N and S pole permanent magnets arranged in a convex shape. Yes.

  The rotor position angle on the horizontal axis of FIG. 4 indicates the angle from the V-phase and U-phase slot centers of FIG. 2 to the magnetic pole center of the rotor 12, and the MAX torque generated during charging in FIG. The minimum is around 15 degrees, about 22.5 degrees, and about 30 degrees, the inductance is almost constant, and the magnet loss is minimum near about 15 degrees and about 30 degrees. Therefore, in the concentrated winding motor shown in FIG. 2, the angle at which the torque vibration and the magnetic loss are minimum is about 15 degrees as shown in FIG. 4 is the target rotor angle. At this target rotor angle, the torque for rotating the rotor is small, and the heat generation of the motor is also suppressed.

  FIG. 3 shows a part of the distributed winding motor. Similarly, FIG. 5 shows motor characteristics of the torque vibration, inductance, and magnet loss of the distributed winding motor 10. The stator 11 in FIG. 3 repeats the U phase, W phase, W phase, V phase, V phase, and U phase clockwise from the left, and the rotor 12 has N and S pole permanent magnets arranged in a convex shape. .

  The rotor position angle on the horizontal axis of FIG. 5 indicates the angle from the center of the W-phase distributed winding in-phase in FIG. 3 to the magnetic pole center of the rotor 12, and the MAX torque generated during charging in FIG. The minimum is 15 degrees, the inductance is maximum at about 7.5 degrees, and the magnet loss is minimum at about 7.5 degrees. Therefore, in the distributed winding motor shown in FIG. 3, as shown in FIG. 5, about 7.5 degrees is the target rotor angle at which the torque vibration and the magnetic loss are minimized and the inductance is maximized. At this target rotor angle, not only the torque for rotating the rotor and the heat generation of the motor are reduced, but also a reduction in charging efficiency can be prevented.

  FIG. 7 shows a process flow of the pre-stop rotor position adjustment method for adjusting the rotor angle when the vehicle is stopped when the charge amount of the secondary battery is reduced to a level that requires charging. When the stop instruction is issued from the vehicle control ECU, the inverter control circuit having the CPU determines whether or not the charge amount of the secondary battery has decreased to the charge level in step S10. If it is determined that charging is necessary, the process proceeds to step S12.

  In step S12, the resolver angle is detected. In step S14, a target rotor angle close to a predetermined stop angle is predicted. In step S16, the inverter is controlled. In step S18, it is determined whether the vehicle has stopped due to a change in the rotor angle. . If it is determined that the vehicle is not stopped, the process returns to step S12, and the rotor angle stop control is executed again. In step S18, when the change in the rotor angle becomes zero and it is determined that the vehicle is stopped at the target rotor angle, the process is terminated and the process returns to the main routine (not shown). With this process, the rotor angle can be set to an optimum position when the vehicle is stopped, and charging control is started by inserting a charging plug, which is a will of charging.

  FIG. 8 shows a processing flow of the pre-charging rotor position adjustment method when charging is started in a state where the vehicle is stopped. In the above-described rotor position adjustment method before stopping, the rotor angle can be set to an optimal state immediately after the vehicle stops. For example, when using midnight power by a timer, from the vehicle stopping to the actual charging start. There is time between. For this reason, in the pre-charging rotor position adjustment method shown in FIG. 8, the rotor angle can be adjusted during this time. In addition, you may use together with the method adjusted before charging control is performed by the charge plug insertion which is the will of charge.

  In the position control shown in FIG. 8, when the vehicle control ECU gives an instruction to start charging when the vehicle is stopped, the inverter control circuit having the CPU determines that charging is performed in step S20 and proceeds to step S22. In step S22, the resolver angle is detected, the deviation from the target rotor angle is calculated to calculate the movement angle, and in step S26, the inverter is controlled to adjust the rotor angle. If the change in the rotor angle does not become zero and does not become the target rotor angle in step S28, step S22 and subsequent steps are executed again, and when the rotor angle becomes the target rotor angle and the change in the rotor angle becomes zero, After the processing, the process returns to the main routine (not shown).

  In the electric vehicle charging device of the present embodiment, since the moving amount of the vehicle is 1 mm or less at the moving angle necessary for adjusting the rotor angle, the rotor angle can be set when the vehicle is stopped. Yes. In FIG. 7, the rotor angle is set when a predetermined condition is satisfied. However, the present invention is not limited to this. For example, the rotor angle may be set when all the vehicles are stopped. It may be executed according to the conditions.

  As described above, by using this embodiment, when the secondary battery is charged, the rotor stop position is controlled to the optimum position, and the rotor rotates to prevent the vehicle from moving. It is possible to prevent occurrence of abnormal noise, temperature rise due to heat generation, reduction in charging efficiency, and the like.

It is a block diagram which shows the structure of the charging device for electric vehicles which concerns on embodiment of this invention. It is a block diagram which shows the structure of the concentrated winding motor which concerns on embodiment of this invention. It is a block diagram which shows the structure of the distributed winding motor which concerns on embodiment of this invention. It is a characteristic view which shows the characteristic of the concentrated winding motor which concerns on embodiment of this invention. It is a characteristic view which shows the characteristic of the distributed winding motor which concerns on embodiment of this invention. It is a time chart figure which shows the inverter control signal of the charging device for electric vehicles which concerns on embodiment of this invention. It is a flowchart figure which shows the flow of a process of the rotor position adjustment system before a stop which concerns on embodiment of this invention. It is a flowchart figure which shows the flow of a process of the rotor position adjustment system before charge which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Charging apparatus for electric vehicles, 10 Motor, 11 Stator, 12 Rotor, 13 Resolver, 14 Inverter, 15 Secondary battery, 16 Inverter control circuit, 18 Zero cross signal generator, 19 Current sensor, 20 Commercial power plug, 21 Connection part , 22 Charging relay, 24, 25, 41, 42, 43, 44, 45, 46 Diode, 26 Main power supply relay, 27 Inrush limiting relay, 28 Main power supply relay, 31, 32, 33, 34, 35, 36 transistors, 51 capacitors, 52 inrush limiting resistors.

Claims (11)

A motor including a secondary battery, a stator and a rotor, an inverter that drives the motor by the power of the secondary battery, and a connection portion that connects an external power source to the neutral point of the motor, and a coil of the motor; In an electric vehicle charging device that uses an inverter to charge a secondary battery from an external power source,
What is claimed is: 1. An electric vehicle charging apparatus comprising: motor control means for stopping a motor at a target rotor angle at which each of torque and magnet loss generated in the motor is minimized in preparation for charging regardless of whether charging is performed. The electric vehicle charging device according to claim 1,
The motor control unit stops the motor at a target rotor angle when stopping the vehicle. The electric vehicle charging device according to claim 1,
An electric vehicle charging apparatus characterized in that the motor control means rotates the motor to a target rotor angle and stops the motor while charging control is actually performed after the vehicle is stopped after the vehicle is stopped. In the electric vehicle charging device according to any one of claims 1 to 3,
The target rotor angle is determined by the characteristics of the motor, and is a rotor angle at which each of torque generated in the motor and magnet loss is minimized and the inductance of the motor is maximized. In the electric vehicle charging device according to any one of claims 1 to 4,
The motor control means positions the rotor at a desired target rotor angle by controlling the inverter. In the electric vehicle charging device according to any one of claims 1 to 5,
When the motor is concentrated winding, the target rotor angle is an angle at which the center of the magnetic pole and the center of the slot coincide with each other. In the electric vehicle charging device according to any one of claims 1 to 5,
When the motor is distributed winding, the target rotor angle is an angle at which the center of the magnet coincides with the center of the teeth between the in-phase slots. A motor including a secondary battery, a stator and a rotor, an inverter that drives the motor by the power of the secondary battery, and a connection portion that connects an external power source to the neutral point of the motor, and a coil of the motor; In a control method of a charging device for an electric vehicle that charges a secondary battery from an external power source using an inverter,
Control of a charging device for an electric vehicle characterized by including a motor control step for stopping the motor at a target rotor angle at which each of torque and magnet loss generated in the motor is minimized in preparation for charging regardless of whether charging is performed Method. In the control method of the charging device for electric vehicles according to claim 8,
In the motor control step, when stopping the vehicle, the motor is stopped at the target rotor angle. In the control method of the charging device for electric vehicles according to claim 8,
The motor control step is a method for controlling a charging device for an electric vehicle, characterized in that after the vehicle is stopped, the motor is rotated to a target rotor angle and stopped while charging control is actually performed after a charging instruction is issued. In the control method of the charging device for electric vehicles according to any one of claims 8 to 10,
The target rotor angle is determined by the characteristics of the motor, and is a rotor angle that minimizes the torque and magnet loss generated in the motor and maximizes the motor inductance. Method.

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