JP2005245104A - Electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric vehicle for possibly extending a travel distance of the vehicle even if a charging rate of a high voltage battery decreases and a voltage converter is failed. <P>SOLUTION: The electric vehicle is provided with the high voltage battery used for a driving source of the vehicle, the voltage converter for partially converting power charged to and discharged from the high voltage battery into a voltage and supplying driving power to electric components, an auxiliary machine motor driven by the power charged to and discharged from the high voltage battery and actuating a compressor of an air conditioner, a blower motor for the air conditioner actuated and receiving the driving power from the voltage converter, and an air conditioner control means for outputting an inhibit signal and inhibiting the operation of the air conditioner when the charging rate of the high voltage battery decreases below a predetermined managing threshold or the voltage converter is failed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electric vehicle that operates a motor that travels and drives wheels using a charging power of a high-voltage battery as a driving source, and operates an air conditioner mounted on the vehicle using the charging power of the high-voltage battery. .

  An electric vehicle using a charging power of a high-voltage battery as a travel drive source is configured to operate a motor that travels and drives wheels using the charging power of the high-voltage battery. Incidentally, the high voltage battery is charged in advance at a dedicated charging station, or is charged using a generator driven by an engine mounted on the vehicle. Furthermore, the high voltage battery is also charged using regenerative energy obtained via the motor during braking of the vehicle. In addition, although the electric vehicle which charges a high voltage battery using the generator driven by the said engine is called a hybrid electric vehicle (HEV), it demonstrates as an electric vehicle including this hybrid electric vehicle here. To do.

  By the way, in an electric vehicle, an air compressor for generating compressed air for brake and a power steering pump for generating hydraulic pressure for power steering are configured to operate using the charging power of the high-voltage battery as a drive source. (For example, refer to Patent Document 1). Furthermore, the above-described charging power of the high voltage battery is also used for the operation of the compressor of an air conditioner (so-called car cooler) mounted on the vehicle (see, for example, Patent Document 2).

On the other hand, for the operation of various control devices (for example, ECUs) and electrical components (for example, audio devices and lighting systems) mounted on the vehicle, the voltage battery (DC / DC converter) is exclusively used to charge the high-voltage battery. A low voltage of about 24 V, for example, obtained by converting the discharge power (about 600 V) into a voltage is used. The low voltage system (electrical power supply system) is usually provided with a low-voltage battery that is charged by the output power of the voltage converter and assists the power supply to the electrical equipment.
JP 2000-23301 JP 2000-62445 A

  By the way, in order to maintain the running performance of an electric vehicle, the power supply from the high-voltage battery that drives the above-described driving motor, air compressor, and the like is stabilized, and various control devices and electrical devices are connected via a voltage converter. It is important to stabilize the power supply to the product. However, for example, if the air conditioner is operated while the charging rate of the high voltage battery is reduced during continuous climbing, the charging power of the high voltage battery is used for the operation of the compressor for the air conditioner that is not directly involved in the running of the vehicle. Therefore, there is a problem that the travelable distance is greatly limited.

  In addition, when the vehicle is running with the voltage converter in a failure state, power is supplied to various control devices and electrical components using only the charging power of the low-voltage battery. Proceed rapidly. Then, when the power supply from the low-voltage battery to the various control devices becomes impossible, the power supply from the high-voltage battery to the drive motor for driving is stopped, and in this case as well, the travelable distance of the vehicle is greatly limited There is a problem to say.

  The present invention has been made in view of such circumstances, and the object thereof is not directly involved in the running of the vehicle when the charging rate of the high voltage battery is reduced or the voltage converter is broken. It is an object of the present invention to provide an electric vehicle that suppresses useless power consumption by suppressing power supply in electrical components, thereby extending the travelable distance of the vehicle as much as possible.

  The present invention relates not only to the wheel drive motor, the air compressor, and the power steering pump in which the charging power of the high-voltage battery used as the vehicle driving source is directly related to the vehicle, but also directly to the vehicle. We pay attention to the fact that it is also used for the operation of auxiliary equipment that does not do, especially the air conditioner, and its power consumption is large. And by stopping the operation of the air conditioner when the charging rate (charging capacity) of the high voltage battery is lowered, etc., all the electric energy charged in the high voltage battery is used for traveling of the vehicle, This aims to extend the travelable distance as much as possible.

Therefore, to achieve the above-described object, the electric vehicle according to the present invention is
<a> a high voltage battery used as a vehicle driving source;
<b> A voltage converter that converts a part of the charge / discharge power of the high-voltage battery to supply driving power to the electrical components provided in the vehicle;
<c> Auxiliary motor driven by charge / discharge power of the high-voltage battery to operate the compressor of the air conditioner;
<d> A blower motor for the air conditioner that operates by receiving driving power from the voltage converter,
<e> Air conditioner control means for prohibiting the operation of the air conditioner by outputting a suppression signal when the charging rate of the high voltage battery falls below a predetermined management threshold or when the voltage converter fails It is characterized by having.

  Preferably, the voltage converter includes a low-voltage battery that is charged by the output power of the voltage converter and assists power supply to the electrical components, and includes a power supply system for the electrical components. Consists of what has been built. According to a third aspect of the present invention, the air conditioner control means monitors the charge occurrence information obtained from the high voltage battery and / or the failure occurrence signal obtained from the voltage converter to monitor the conditioner. A suppression signal for prohibiting the operation of the auxiliary motor and the blower motor that drives the compressor is output.

  According to the electric vehicle configured as described above, when the charging rate of the high-voltage battery is reduced to, for example, 20% or less, or when the voltage converter breaks down, the voltage converter is changed to various control devices and electrical components. When the power supply of the air conditioner cannot be performed, it is not directly involved in the running of the vehicle and the operation of the air conditioner with high power consumption is prohibited. Power consumption from the low voltage battery can be suppressed. Therefore, it is possible to extend the travelable distance of the vehicle by the charging power of the high-voltage battery and / or the low-voltage battery by the amount of power consumption associated with the operation of the air conditioner.

  Further, the charging rate information obtained from the high voltage battery and / or the failure occurrence signal obtained from the voltage converter is monitored to output a suppression signal for prohibiting the operation of the air conditioner, and thereby the air conditioner Since it is only necessary to inhibit the operation of the auxiliary motor and the blower motor that drive the compressor, the control itself is simple. In addition, the control function can be easily incorporated into an existing electric vehicle.

Hereinafter, an electric vehicle according to an embodiment of the present invention will be described with reference to the drawings, taking as an example a series type hybrid electric vehicle (HEV) that uses the driving force of an engine as a driving source of a generator.
FIG. 1 is a diagram showing a schematic configuration of an electric system of a series hybrid electric vehicle (HEV) to which the present invention is applied, and 1 is a high voltage battery used as a drive source of the hybrid vehicle. The high-voltage battery 1 is charged from the outside at a charging station (not shown), or is charged by electric power generated using a generator 3 driven by an engine 2 mounted on the vehicle. Note that charging of the high voltage battery 1 using the generator 3 is performed via an inverter 4 that controls charging and discharging of the high voltage battery 1.

  The charging / discharging power of the high-voltage battery 1 through the inverter 4 generates a traveling motor 6 for driving the wheels 5 and 5, an air compressor 7 for generating compressed air for braking, and a hydraulic pressure for power steering. The first auxiliary motor 9 for driving the power steering pump 8 and the second auxiliary motor 11 for driving the cooler compressor 10 for the air conditioner are used. The operations of the first and second auxiliary motors 9 and 11 are controlled by a motor controller 12 described later.

  On the other hand, the charge / discharge power of the high-voltage battery 1 is also supplied to a voltage converter (DC / DC converter) 13. This voltage converter 13 converts the high voltage of about 600 V, for example, which is the output of the high voltage battery 1 into a low voltage of 24 V, and supplies it to the blower motor 14 for the air conditioner and the electrical components 15 such as the illumination system in the vehicle. Plays the role of supplying power. In addition, a power supply system (low voltage system) that supplies driving power from the voltage converter 13 to the blower motor 14 and the electrical components 15 is charged by the output power of the voltage converter 13 to be charged with the blower motor 14 and electrical components 15. A low voltage battery (24V battery) 16 is provided to assist the power supply to the battery.

  The second auxiliary motor 11 that drives the cooler compressor 10 and the air conditioner blower motor 14 for operating the air conditioner described above operate under the control of the cooler controller 17. That is, when a cooler switch (not shown) is turned on, the cooler controller 17 detects this and outputs a cooler operation signal to operate the blower motor 14 and outputs the cooler operation signal to the motor controller 12. The second auxiliary motor 11 is actuated by giving.

  In the electric system of the electric vehicle (series hybrid electric vehicle) basically configured as described above, the present invention is characterized by monitoring the charging rate of the high voltage battery 1 and the voltage converter 13. When the operating state is monitored and the charging rate of the high-voltage battery 1 falls below a predetermined monitoring threshold, for example, when the charging rate falls below 20%, or when the voltage converter 13 fails, the cooler controller 17 is And a signal converter 18 for outputting a compressor suppression signal.

  That is, the high-voltage battery 1 obtains the charging rate of the high-voltage battery 1 by monitoring its charge / discharge current value and charge / discharge time, for example, with a built-in charge / discharge monitoring unit (not shown). The voltage converter 13 monitors the output voltage (voltage converted 24V voltage) to determine whether or not the voltage converter 13 has failed, and outputs a failure signal when a failure is detected. The signal converter 18 inputs information on the charging rate from the high-voltage battery 18 and displays the charging rate on the display 19. When a failure signal is given from the voltage converter 13, the voltage converter 18 13 is provided with a function of notifying information (alarm) that 13 has failed via the display 19. Further, when the charging rate of the high-voltage battery 1 falls below a predetermined monitoring threshold (charging rate is 20%), the signal converter 18 determines this as a reduction in charging rate. And when the charging rate falls or when the voltage converter 13 breaks down, a cooler suppression signal for stopping the operation of the air conditioner is issued.

  Specifically, for example, as shown in FIG. 2, the signal converter 18 compares the charging rate given from the high-voltage battery 1 with a predetermined monitoring threshold (charging rate is 20%) given as the comparison reference voltage Vref. , An OR circuit 22 that outputs a cooler suppression signal in response to a charge rate decrease signal output from the comparator 21 or a failure signal from the voltage converter 13 when the charge rate decreases, and a motor from the cooler controller 17. And a gate circuit 23 configured to turn on / off a cooler operation signal supplied to the controller 12 in accordance with the cooler suppression signal. The cooler suppression signal is given to the cooler controller 17 so that the operation of the air conditioner based on the control of the cooler controller 17, and thus the second auxiliary motor 11 for driving the cooler compressor 10 and the blower motor 14 for the air conditioner. Are controlled to stop.

  Thus, according to the electric vehicle (series hybrid electric vehicle) provided with the control system configured as described above, when the charging rate of the high-voltage battery 1 directly involved in the driving of the vehicle decreases or the voltage converter 13 fails. Then, the operation of the air conditioner that is not directly involved in the running of the vehicle is controlled to stop. Therefore, since the second auxiliary motor 11 for driving the cooler compressor 10 does not operate when the charging rate of the high-voltage battery 1 is lowered, the valuable battery energy remaining in the high-voltage battery 1 is used for running the vehicle. It can be used effectively. Therefore, the travelable distance of the vehicle can be extended by the amount that the charging power of the high-voltage battery 1 is not consumed by the second auxiliary motor 11. When the voltage converter 13 fails, the charging power of the low voltage battery 16 is not used for driving the blower motor 14 for the air conditioner. Therefore, the charging power stored in the low voltage battery 16 is used as an ECU or the like. It can be effectively used for the operation of the electrical components 15 including the control device. Accordingly, since the operation of the control device for the travel drive system can be ensured as much as unnecessary power consumption in the blower motor 14 for the air conditioner is suppressed, the travelable distance of the vehicle can be extended. That is, it is possible to secure the maximum travelable distance of the vehicle according to the remaining charge amount of the high voltage battery 1 and the charge amount of the low voltage battery 13.

  The present invention is not limited to the embodiment described above. Although the series hybrid electric vehicle has been described here, the parallel hybrid electric vehicle that uses the driving force of the engine 2 for both the driving of the generator 3 and the driving of the wheels 5, and the engine 2 and the engine 2 are used for driving. The above-described control can be similarly applied to an electric vehicle equipped with only a high-voltage battery or a fuel cell without the generator 3. The degree to which the operation of the air conditioner is prohibited when the charging rate of the high-voltage battery 1 is reduced may be determined according to the specifications of the high-voltage battery 1 and the running performance of the vehicle. In addition, the present invention can be variously modified and implemented without departing from the scope of the invention.

The figure which shows schematic structure of the electric system | strain of the electric vehicle which concerns on one Embodiment of this invention. The figure which shows the structural example of the signal converter in the electric vehicle shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High voltage battery 4 Inverter 6 Travel drive motor 9 1st auxiliary machine motor 10 Cooler compressor 11 2nd auxiliary machine motor 12 Motor controller 13 Voltage converter (DC / DC converter)
14 Blower motor 15 Electrical components 16 Low voltage battery 17 Cooler controller 18 Signal converter

Claims (3)

A high voltage battery used as a driving source of the vehicle;
A voltage converter for converting a part of the charge / discharge power of the high-voltage battery to supply driving power to the electrical components provided in the vehicle;
An auxiliary motor that is driven by the charge / discharge power of the high-voltage battery to operate the compressor of the air conditioner;
A blower motor for the air conditioner that operates by receiving driving power from the voltage converter;
Air conditioner control means for outputting a suppression signal and prohibiting the operation of the air conditioner when the charging rate of the high voltage battery falls below a predetermined management threshold or when the voltage converter fails. An electric car characterized by that.   2. The electric power according to claim 1, wherein the voltage converter includes a low-voltage battery that is charged by an output power of the voltage converter in an electric power supply system for the electric components and assists power supply to the electric components. Automobile.   The air conditioner control means monitors the charge rate information obtained from the high voltage battery and / or a failure occurrence signal obtained from the voltage converter, and drives the compressor motor of the air conditioner, and The electric vehicle according to claim 1, wherein a suppression signal for prohibiting the operation of the blower motor is output.

Images