JP4686394B2 - Electric vehicle control device - Google Patents

Description

  The present invention relates to an electric vehicle control device.

  In general, a variable voltage variable frequency inverter (VVVF inverter) is adopted as a DC / AC conversion device in an electric vehicle driving device that drives DC electric power of an overhead wire by DC / AC conversion and supplying it to an electric vehicle motor. This VVVF inverter has a reversible characteristic, and can perform a function of converting surplus energy of the electric motor to AC / DC conversion and returning it to the overhead line side during regenerative braking.

  However, a light load regenerative state in which the load for absorbing regenerative energy on the overhead line side is insufficient may occur, and in such a case, an increase in the overhead line voltage is detected by an increase in the filter capacitor voltage of the VVVF inverter, The so-called regenerative limiter control is performed in which the regenerative braking force is narrowed according to the voltage value to suppress the rise of the overhead wire voltage. In this case, the braking force that becomes insufficient by narrowing the regenerative braking force is supplemented by the mechanical brake. However, when the regenerative braking force is reduced to increase the supplement of the mechanical brake, not only the energy saving effect is diminished, but the wheel may be heated and in some cases may cause metal fatigue of the wheel.

  In view of such technical problems, conventionally, an electric vehicle control device having a configuration shown in FIG. 7 has been developed. In FIG. 7, 1 is a DC / DC converter, 3 is a power storage device such as an electric double layer, 5 is a reactor, 10 is a high-speed circuit breaker, 11 is a charging resistor, 12 is a charging resistor short-circuit contactor, 13 Is a pantograph for taking in overhead power, 14 is a wheel, 15 is a VVVF inverter, 16 is an electric vehicle motor, and 18 is a filter capacitor.

  In such a conventional electric vehicle control device, when the regenerative load is insufficient, the energy for the shortage of the regenerative load that cannot be returned to the overhead wire side is absorbed into the power storage device 3 via the DC / DC converter 1, thereby the overhead wire. By suppressing the increase in voltage and increasing the usage rate of the regenerative brake, the usage rate of the mechanical brake can be suppressed.

However, since the capacity of the power storage device 3 is limited, for example, in a state where the regenerative brake is continuously operated for a long time on a downward slope, the power storage device 3 cannot absorb all the regenerative energy. Happens. Therefore, conventionally, when the power storage device 3 is fully charged and thus cannot absorb regenerative energy, the regenerative braking force is also throttled to switch to mechanical braking. Since the mechanical brake is a brake that is mechanically operated by applying a brake shoe to the wheel tread surface, if the mechanical brake is frequently used, the wheel temperature rises, causing metal fatigue and wear of the brake shoe. For this reason, energy storage using an electric power storage device is unsuitable for an application in which a regenerative brake is operated continuously for a long time in a line with many gradients, and a solution has been demanded.
JP 2003-18702 A JP 2003-199203 A JP 2003-199332 A R & M May, 2005, Development of vehicle-mounted "power storage system" using electric double layer capacitor

  The present invention has been made in view of the above-described problems of the prior art, and the power storage device is fully charged in a traveling state with a large amount of regenerative energy, such as when an electric vehicle travels on a long downward slope. Another object of the present invention is to provide an electric vehicle control device including an electric power storage device that can continuously use a regenerative braking force and can perform brake control without using a mechanical brake.

An electric vehicle control device of the present invention is connected in parallel to a VVVF inverter that drives an electric vehicle motor, a power storage device for absorbing regenerative energy of the electric vehicle motor, and a DC side of the VVVF inverter, A DC / DC converter whose conversion output is connected to the power storage device, a first contactor for turning on and off the output from the DC / DC converter in the power storage device, and a brake for consuming the regenerative energy A resistor, a brake chopper connected in parallel with the DC / DC converter on the DC side of the VVVF inverter, the output of which is connected to the brake resistor, and an output from the brake chopper for turning on and off the brake resistor. and 2 of the contactor, the brake chopper when the power storage device is fully charged state during regenerative braking By operating a general control circuit which performs regenerative energy absorption and consumption control to consume the regenerative energy by the brake resistor, the integrated control circuit, when the state of charge of the power storage device is not fully charged the second And the first contactor is closed and the regenerative energy is absorbed by the power storage device through the DC / DC converter, and when the state of charge of the power storage device is fully charged, When the first contactor is opened and the second contactor is closed and the regenerative energy is consumed by the brake resistance, and the vehicle power is turned off, the first contactor and the second contactor And controlling the discharge of the energy remaining in the power storage device to the brake resistor .
The electric vehicle control device according to the present invention is connected in parallel to the VVVF inverter that drives the electric vehicle motor, the power storage device that absorbs regenerative energy of the electric vehicle motor, and the DC side of the VVVF inverter. A DC / DC converter whose conversion output is connected to the power storage device, a first contactor for turning on and off the output from the DC / DC converter in the power storage device, and for consuming the regenerative energy And a brake chopper connected in parallel with the DC / DC converter on the DC side of the VVVF inverter, the output of which is connected to the brake resistor, and an output from the brake chopper to the brake resistor. A second contactor that performs regenerative braking and the brake clutch when the power storage device is fully charged. An overall control circuit for performing regenerative energy absorption / consumption control by operating a pad and consuming the regenerative energy by the brake resistance; a connection line between the first contactor and the power storage device; and the second contact. A third contactor that automatically closes when the vehicle power source is turned off and discharges the energy remaining in the power storage device to the brake resistor between the connection line of the brake device and the brake resistor. The integrated control circuit opens the second contactor when the state of charge of the power storage device is not fully charged, and closes the first contactor and passes the regenerative energy through the DC / DC converter. Is absorbed by the power storage device, and when the state of charge of the power storage device is fully charged, the first contactor is opened, and the second contactor is closed and the brake resistor is used. It is characterized in that the control to consume the serial regenerative energy.

According to the electric vehicle control device of the present invention, the regenerative brake can be continuously used even when the power storage device is fully charged in a state where the regenerative energy is large, such as when the electric vehicle travels on a long downward slope. The brake can be controlled without using the mechanical brake, and as a result, the number of unnecessary uses of the mechanical brake can be reduced and the mechanical life can be extended. In addition, if the vehicle power supply is turned off, such as when an electric vehicle enters the garage, the energy remaining in the power storage device can be discharged for safety.

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

  (First Embodiment) FIG. 1 shows a circuit configuration of an electric vehicle control apparatus according to a first embodiment of the present invention, and FIG. 2 shows a configuration of an overall control circuit that controls regenerative control. 1 and 2, 1 is a DC / DC converter, 2 is a brake chopper, 3 is a power storage device such as an electric double layer, 4 is a brake resistor, 5 is a reactor, 10 is a high-speed circuit breaker, 11 is Charging resistor, 12 is a contact resistor for short-circuiting charging resistor, 13 is a pantograph, 14 is a wheel, 15 is a VVVF inverter for DC / AC conversion of overhead power, 16 is an electric vehicle motor, 17 is an overall control circuit, 18 is a filter capacitor It is.

  The electric vehicle control device according to the present embodiment has a DC / DC converter 1 that supplies energy to the power storage device 3 and a brake chopper 2 that consumes energy to the brake resistor 4, and the power storage device according to the voltage value of the overhead line voltage. 3 is provided with a function of switching control between energy supply to 3 and energy consumption by the brake resistor 4.

  In order to drive the electric vehicle motor 16 to run the electric vehicle, the pantograph 13 takes in the overhead wire power, charges the high-speed circuit breaker 10 and the charging resistor short-circuit contactor 12 with the filter capacitor 18, The voltage between both ends of the filter capacitor 18 is DC / AC converted at a variable voltage and variable frequency by the VVVF inverter 15 and supplied to the electric vehicle motor 16. In addition, the charging resistor 11 and the charging resistor short-circuit contactor 12 open the charging resistor short-circuiting contactor 12 so that a large inrush current does not flow from the overhead line at the start-up, and flow the inrush current to the charging resistor 11. When the current settles, the charging resistance short-circuit contactor 12 is closed to supply a stable current to the VVVF inverter 15.

  When the amount of energy stored in the power storage device 3 is less than the capacity, the overall control circuit 17 operates the DC / DC converter 1 to absorb the regenerative energy into the power storage device 3 and is stored in the power storage device 3. When the amount of energy is full, the brake chopper device 2 is operated and the regenerative energy is consumed by the brake resistor 4.

  The control operation by the overall control circuit 17 will be described with reference to FIGS. A regenerative energy absorption command α is commanded from the VVVF inverter 15. Upon receiving this command α, the overall control circuit 17 determines the power storage device absorption energy command β by limiting the regenerative energy absorption command α based on the instantaneous absorption energy of the power storage device 3 and the voltage VE of the power storage device 3. The overall control circuit 17 also determines the brake resistance absorption energy command γ as a value obtained by subtracting the power storage device absorption energy command β from the regenerative energy absorption command α. That is, the overall control circuit 17 performs control to consume the energy that could not be absorbed by the power storage device 3 with the brake resistance.

  According to the present embodiment, the energy stored in the power storage device 3 operates when the brake chopper 2 is continuously operated because the brake chopper 2 operates when the amount of energy is full. Energy absorption into the power storage device 3 can be performed, the regenerative brake can be continuously used, and the brake control can be performed without using the mechanical brake.

  (Second Embodiment) An electric vehicle control apparatus according to a second embodiment of the present invention will be described. The circuit configuration of the electric vehicle control device of the present embodiment is as shown in FIG. 5, and the functional configuration of the overall control circuit 17 is as shown in FIG. 2 as in the first embodiment.

  The electric vehicle control device of this embodiment is different from the configuration of the first embodiment shown in FIG. 1 in that the power storage device 3 has an opening contactor EK7 and the brake resistor 4 has an opening contactor. A BK 8 is attached, and a power converter 6 having a function as the DC / DC converter 1 and a function as the brake chopper 2 is provided instead of these. In FIG. 5, elements common to the circuit elements of the first embodiment shown in FIG.

  In the electric vehicle control device of the present embodiment, when the amount of energy stored in the power storage device 3 is less than the capacity, the overall control circuit 17 turns on the contactor EK7 and turns off the contactor BK8. Thus, the power converter 6 is operated as a DC / DC converter, and the regenerative energy is absorbed by the power storage device 3. When the amount of energy stored in the power storage device 3 is full, the overall control circuit 17 turns off the contactor EK7 and turns on the contactor BK8 to operate the power converter 6 as a brake chopper. Regenerative energy is consumed by the brake resistor 4.

  In the case of the present embodiment, the brake resistance 4 is used as the discharge resistance of the power storage device 3 by simultaneously turning on both the contactor EK7 and the contactor BK8 by the overall control circuit 17. For example, such control can be performed when the energy remaining in the power storage device 3 is discharged for safety when the electric vehicle enters the garage.

  As a means for discharging the energy remaining in the power storage device 3, as shown in FIG. 6, a contactor HK9 is inserted between the power storage device 3 and the brake resistor 4, and the contactor HK9 is connected to the vehicle. By using a contactor that is turned on mechanically when the power is turned off, the brake resistor 4 and the power storage device 3 can be automatically connected and discharged when the vehicle power is turned off.

  According to the present embodiment, the power converter 6 is operated as a DC / DC converter so that regenerative energy is stored in the power storage device 3, and when the energy amount of the power storage device 3 is full, the power converter 6 is turned on. Since it is operated as a brake chopper and regenerative energy is consumed by the brake resistor 4, energy is absorbed into the power storage device 3 and continuously even when the brake is continuously operated on a downward slope or the like. Thus, the regenerative brake can be continuously used, and the brake control can be performed without using the mechanical brake. In addition, in the present embodiment, since the power converter 6 has both the DC / DC converter function and the brake chopper function, the number of articles can be reduced, and the size and weight can be reduced.

The circuit diagram of the electric vehicle control apparatus of the 1st Embodiment of this invention. The block diagram which shows the function structure of the integrated control circuit which supervises regenerative energy absorption control in the electric vehicle control apparatus of the said embodiment. Explanatory drawing of the regenerative energy absorption control function of the overall control circuit in the electric vehicle control apparatus of the above embodiment. Explanatory drawing of the regeneration energy absorption control operation | movement by the integrated control circuit in the electric vehicle control apparatus of the said embodiment. The circuit diagram of the electric vehicle control apparatus of the 2nd Embodiment of this invention. The circuit diagram of the modification of the regenerative energy absorption and consumption circuit part in the electric vehicle control apparatus of the said embodiment. The circuit diagram of the conventional electric vehicle control apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 DC / DC converter 2 Brake chopper 3 Electric power storage device 4 Brake resistance 5 Reactor 6 Converter 7 Contactor EK
8 Contactor BK
9 Contactor HK
DESCRIPTION OF SYMBOLS 10 High speed circuit breaker 11 Charging resistance 12 Charging resistance short circuit contactor 13 Pantograph 14 Wheel 15 VVVF inverter 16 Electric motor 17 Overall control circuit 18 Filter capacitor

Claims (5)

A VVVF inverter for driving an electric vehicle motor;
A power storage device for absorbing regenerative energy of the electric vehicle motor;
A DC / DC converter connected in parallel to the DC side of the VVVF inverter, the conversion output of which is connected to the power storage device;
A first contactor for turning on and off the output from the DC / DC converter in the power storage device;
Brake resistance for consuming the regenerative energy;
A brake chopper connected in parallel with the DC / DC converter on the DC side of the VVVF inverter, the output of which is connected to the brake resistor;
A second contactor for turning on and off the output from the brake chopper to the brake resistance;
An overall control circuit for performing regenerative energy absorption and consumption control for operating the brake chopper and consuming the regenerative energy with the brake resistance when the power storage device is fully charged during regenerative braking ,
The overall control circuit opens the second contactor when the state of charge of the power storage device is not fully charged, and closes the first contactor to supply the regenerative energy through the DC / DC converter. When the power storage device is absorbed, the first contactor is opened when the state of charge of the power storage device is full, and the second contactor is closed and the regenerative energy is consumed by the brake resistor. And when the vehicle power supply is turned off, the first contactor and the second contactor are both closed, and control is performed to discharge the energy remaining in the power storage device to the brake resistor. Electric vehicle control device. A VVVF inverter for driving an electric vehicle motor;
A power storage device for absorbing regenerative energy of the electric vehicle motor;
A DC / DC converter connected in parallel to the DC side of the VVVF inverter, the conversion output of which is connected to the power storage device;
A first contactor for turning on and off the output from the DC / DC converter in the power storage device;
Brake resistance for consuming the regenerative energy;
A brake chopper connected in parallel with the DC / DC converter on the DC side of the VVVF inverter, the output of which is connected to the brake resistor;
A second contactor for turning on and off the output from the brake chopper to the brake resistance;
An overall control circuit for performing regenerative energy absorption and consumption control for operating the brake chopper when the power storage device is fully charged during regenerative braking and consuming the regenerative energy with the brake resistance;
Between the connection line between the first contactor and the power storage device, and the connection line between the second contactor and the brake resistor, when the vehicle power source is turned off, it is automatically closed and the A third contactor for discharging the energy remaining in the power storage device to the brake resistor;
The overall control circuit opens the second contactor when the state of charge of the power storage device is not fully charged, and closes the first contactor to supply the regenerative energy through the DC / DC converter. When the power storage device is absorbed, the first contactor is opened when the state of charge of the power storage device is full, and the second contactor is closed and the regenerative energy is consumed by the brake resistor. it characterized in that the control makes electrical vehicle control device. The integrated control circuit monitors the state of charge of the power storage device, according to claim 1 or 2 electric vehicle, wherein the product that controls the regenerative energy sharing between the DC / DC converter and the brake chopper Control device. The overall control circuit controls to decrease the absorbed power command value of the DC / DC converter and increase the power consumption command value of the brake chopper when the state of charge of the power storage device is fully charged. The electric vehicle control device according to claim 3 .   The electric vehicle control device according to any one of claims 1 to 4, further comprising a power converter that doubles as the DC / DC converter and the brake chopper.

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