JP2009083670A - Electric automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric automobile capable of enhancing the durability of a battery and a cooling means by efficiently cooling a power supply unit at low cost even if executing a quick charge. <P>SOLUTION: The electric automobile comprises a cooling means 15 for cooling a power supply unit 5 of a motor 2 for driving wheels 3, a temperature detection means 21 for detecting the temperature status of the power supply unit, a charging state detection means 101 for detecting whether or not the power supply unit is in quick charging by an external charger 121A, and a control means 100 for controlling the cooling means. When the temperature T of the power supply unit during the quick charging is higher than predetermined values T1, T2 based on detection information from the temperature detection means 21 and the charging state detection means 101, the control means 100 performs control to actuate the cooling means 15. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electric vehicle that cools a power supply unit of a motor by cooling means.

  An electric vehicle has a motor as a driving source and a battery as a power source mounted on the vehicle body. In electric vehicles, the performance and capacity of the battery will affect the distance traveled. Therefore, it is usually configured so that a plurality of rechargeable batteries are installed as a unit and can be charged when the battery voltage drops due to discharge. Yes. 2. Description of the Related Art Conventionally, it is known that a battery for an electric vehicle is deteriorated in life performance due to repeated charging and discharging. It is also known that the deterioration is accelerated depending on the temperature environment. In other words, since the battery generates heat during charging / discharging, it is required to optimize the temperature environment during charging / discharging.

  Therefore, Patent Document 1 proposes an invention in which a cooling device is operated even during external charging of the battery to suppress an increase in the temperature of the battery and suppress deterioration of the battery due to external charging.

Japanese Patent No. 28944427

  For external charging of the battery of an electric vehicle, a normal charging method in which charging is performed using an AC power source of 100 volts or 200 volts, and an alternating current power source is converted into a direct current, and the normal charging method is performed in a short time with a higher voltage and current. There is a quick charging method to charge. In the case of the normal charging method, for example, since charging takes 7 to 14 hours, the current per unit time does not increase so much. For this reason, heat generation by charging in the normal charging system is often within an allowable range. However, in the case of charging by the rapid charging method, the current per unit time is many times that of the normal charging method, so that heat generation is large. Further, in the case of rapid charging, since it is assumed that the vehicle travels after charging, the battery that generates heat due to charging further generates heat due to traveling before it dissipates heat.

  In addition, when the battery is cooled by the cooling device, it is conceivable that an operating sound of a blower such as a fan is generated. For example, in the case of a normal charging method in which charging is performed using a household power source, it is assumed that nighttime power is used at a low electricity charge, but it is not preferable that the operation sound of the blower is intermittently generated at midnight.

  When operating the cooling device during both normal charging and quick charging, the frequency of use of the cooling fan increases, so the durability required for the cooling fan increases and it becomes difficult to divert the existing cooling fan. Leading to increased costs.

  Furthermore, the fact that the power supply unit needs to be cooled during normal charging, where the temperature of the power supply unit is not expected to rise significantly, may indicate that some sort of malfunction has occurred. Sometimes it is not always good to continue.

In Patent Document 1, there is no room for improvement in consideration of the durability of the battery, without considering such a time of rapid charging.
The present invention proposes an electric vehicle capable of efficiently cooling a power supply unit at a low cost even when rapid charging is performed, and improving the durability of the battery and the cooling means as compared with the prior art. And that is the purpose.

  In order to achieve the above object, the invention of claim 1 is directed to a motor for driving a wheel, a cooling means for cooling a power supply part of the motor, a temperature detection means for detecting a temperature state of the power supply part, and the power supply part being externally charged. Charging state detection means for detecting whether or not the battery is being rapidly charged, and control means for controlling the cooling means, the temperature of the power supply unit at the time of rapid charging is determined from the detection information from the temperature detection means and the charging state detection means When the temperature is higher than the predetermined temperature, the control means controls the cooling means to operate.

  According to a second aspect of the present invention, in the electric vehicle according to the first aspect, the cooling means includes a blower driving motor that drives the blower fan and an air conditioner unit that generates a cooling airflow, and a power supply unit from the air conditioner unit through a duct. Provided with a discharge drive motor that drives a discharge fan that discharges the cooling airflow supplied to the outside of the vehicle, and based on detection information from the temperature detection means and the charge status detection means, the temperature of the power supply unit during rapid charging is higher than the first temperature In this case, the blower drive motor and the discharge drive motor are operated to drive the blower fan and the exhaust fan. When the temperature of the power supply unit at the time of quick charging is the second temperature higher than the first temperature, the compressor is turned on. It is characterized by being controlled by the control means so as to be additionally operated.

  According to a third aspect of the present invention, in the electric vehicle according to the second aspect, the operation of the discharge drive motor is controlled by the control means so that the rotation of the discharge fan increases as the temperature of the power source increases.

  According to the present invention, when the temperature of the power supply unit at the time of rapid charging is higher than a predetermined temperature, the cooling unit operates, so that the power supply unit that has generated heat by the rapid charging can be cooled, and the power supply unit is more than conventional. It is possible to improve the durability. In addition, since the power supply is cooled only for a short time during rapid charging, the durability required for the cooling means does not change significantly, and the existing cooling means can be diverted, preventing a significant increase in cost. In addition, the user's convenience is less impaired by the operating sound of the cooling means. Furthermore, since the power supply unit is not cooled during normal charging, if any trouble occurs in the power supply unit, it can be detected early.

  According to the present invention, when the temperature of the power supply unit at the time of quick charging is higher than the first temperature, the blower drive motor and the discharge drive motor are operated to drive the blower fan and the exhaust fan. When the temperature of the second temperature is higher than the first temperature, the compressor is additionally operated, so that the cooling capacity by the cooling means is changed corresponding to the temperature change of the power supply unit, and excessive power consumption It is possible to effectively cool the power supply unit while suppressing charging, leading to improved charging efficiency.

  According to the present invention, since the discharge drive motor is operated so that the rotation of the discharge fan becomes higher as the temperature of the power supply unit becomes higher, the circulation efficiency of the cooling air is improved and the power supply unit can be cooled more effectively. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In FIG. 1, an electric vehicle denoted by reference numeral 1 travels by rotating a wheel 3 by driving a motor 2. A battery unit 5 serving as a power source for the motor 2 is disposed below the seat 4 provided in the passenger compartment 20 of the electric vehicle 1. The battery unit 5 is configured as a battery pack including a plurality of cells as one module and a plurality of these modules. The battery unit 5 is housed in a unit housing portion 8 composed of a floor panel 6 constituting the vehicle body and a shielding plate 7 provided below the floor panel 6.

  The electric vehicle 1 includes a battery control unit 9, a cooling unit 15 for cooling the battery unit 5, a temperature detection sensor 21 serving as a temperature detection unit for detecting the temperature state of the battery unit 5, and the battery unit 5 as shown in FIG. A charging status detection means 101 for detecting whether or not rapid charging by the external charger 121A is in progress; a cooling control section 10 for controlling the cooling means 15; a control means 100 for controlling the battery control section 9 and the cooling control section 10; An in-vehicle charger 121A that performs normal charging is provided.

  The cooling means 15 includes a blower fan 14 disposed in the outside air introduction path 13, a blower driving motor 141 that drives the blower fan 14, and a compressor 18. An air conditioner unit 150 that cools the outside air by circulating the refrigerant between the heat exchanger 17 disposed in the heat exchanger 17 and generates cooling air, and the air from the air conditioner unit 150 into the unit housing 8 via the duct 16. A discharge fan 11 that discharges the entire supplied cooling airflow to the outside of the vehicle and a discharge drive motor 11 that drives the discharge fan 11 are provided.

  The air conditioner unit 150 includes an indoor cooling outlet 15 a that introduces the cooling airflow S into the vehicle interior 20 and a battery cooling outlet 15 b that guides the cooling airflow to the unit housing portion 8, and both are configured to be switched by a damper 19. Has been.

  An introduction port 8a is formed on the front side of the unit storage portion 8, and a discharge fan 11 is mounted on the discharge port formed on the rear side 8b. The discharge fan 11 is for sucking air into the unit storage portion 8, and is configured such that the air in the unit storage portion 8 is discharged when the fan rotates.

  One end 16a is connected to the battery cooling air outlet 15b and the other end 16b of the duct 16 is formed in the introduction port 8a. The other end 16b of the duct 16 is formed inside the flow path for guiding the cooling airflow S from the air conditioner unit 150 to the unit storage portion 8. Has been. The battery unit 5 in the unit storage portion 8 is configured to be cooled by the cooling airflow S guided and introduced through the duct 16. In this embodiment, the duct 16 is disposed on the floor 6 on the passenger seat 4A side.

  The on-board normal charger 121A is charged with, for example, a voltage of 100 volts / 15 amps, and a socket 12A connected to a 100V supply outlet 123 installed outside the vehicle is connected via a charging cable 122. Yes.

  The quick charger 121B installed outside the vehicle is charged with, for example, a three-phase voltage of 200 volts / 50 kW, and a socket 12B extends through a cable. The electric vehicle 1 is provided with a connector 124 to which the socket 12B is attached. The charging status detection means 101 detects that the quick charger 121B (socket 12B) is connected to the connector 124, and may be, for example, a voltmeter or a mechanical device provided in the vicinity of the connector 124. It may be a switch. The charging status detection unit 101 is connected to the control unit 100 via a signal line and outputs charging status detection information.

  The battery control unit 9 controls charging and temperature of the battery unit 5, and the battery unit 5, the temperature detection sensor 21, and the discharge drive motor 111 that operates the discharge fan 11 are connected. An operation command is transmitted to the discharge drive motor 111 to control the operation of the discharge drive motor 111.

  The cooling control unit 10 is connected with a damper drive unit 191 that drives the compressor 18, the air blowing drive motor 141, and the damper 19 to switch the outlet of the cooling airflow, and transmits an operation command to each drive unit. It is comprised so that the action | operation of a drive part may be controlled.

  The battery control unit 9, the cooling control unit 10, and the control unit 100 are configured by a known computer. The control unit 100 includes a battery control unit 9, a cooling control unit 10, and a charging status detection unit 101 connected by a signal line, and the temperature information from the temperature detection sensor 21 transmitted from the battery control unit 9 and the charging status detection unit. It is determined from the detection information from 101 whether the temperature T of the battery unit 5 is in a quick charge state, and when the temperature T of the battery unit 5 is higher than a predetermined temperature, the cooling means 15 is controlled to operate. It has a function to do. Specifically, the control unit 100 determines that the temperature T of the battery unit 5 at the time of rapid charging is set to the control unit 100 in advance based on detection information from the temperature detection sensor 21 and the charging state detection unit 101. When higher than T1, the discharge drive motor 111 and the blower drive motor 141 are operated to drive the exhaust fan 11 and the blower fan 14, and the temperature T of the battery unit 5 at the time of quick charge is higher than the first temperature T1. When the temperature T2 is 2 (T1 <T2), the compressor 18 is additionally operated.

  The cooling operation of the battery unit 5 having such a configuration will be described with reference to the flowchart shown in FIG.

  The electric vehicle 1 travels when the motor 2 is driven by the electric power supplied from the battery unit 5 to the motor 2 and the wheels 3 are rotated. Since the battery unit 5 is discharged during traveling, power is consumed and heat is generated.

  Here, when the discharge of the battery unit 5 progresses and the remaining amount decreases, charging becomes necessary. For example, when parking without running after completion of charging, the socket 12A is connected to an outlet 123 outside the vehicle shown in FIG. In this case, since charging is performed at an output of 100 volts / 15 amperes, charging time is required, but the heat generation amount is suppressed.

  On the other hand, when the vehicle travels again after the charging is completed, the socket 12B of the quick charger 121A shown in FIG. In this case, since charging is performed at an output of 200 volts / 50 kW, the charging time is shorter than that of normal charging, but the amount of heat generation is increased.

  At this time, the control means 100 determines whether or not rapid charging is being performed in step A1 from the detection information from the charging status detection means 101, and proceeds to step A2 in the case of rapid charging. In Step A, it is determined whether or not the temperature information (battery temperature T) from the temperature detection sensor 21 exceeds the set first temperature T1, and if it does not exceed the first temperature T1, There is no need for cooling.

  On the other hand, if the temperature exceeds the first temperature T1, it is determined that cooling is necessary, and the process proceeds to step A3 to issue an air conditioning system operation command. When this command is issued, the blower drive motor 141, the damper drive unit 191 and the discharge drive motor 111 constituting the air conditioning system are operated in step A4. When these actuate, the damper 19 is switched to the battery cooling air outlet 15b, and the blower fan 14 and the exhaust fan 11 rotate, so that the outside air from the outside air introduction path 13 becomes a blast air current through the battery cooling air outlet 15b and the duct 16. The battery is supplied to the battery storage unit 8. The supplied air flow removes heat from the battery unit 5 in the battery housing 8 and is discharged out of the vehicle by the exhaust fan 11. The battery unit 5 is cooled when such a blast airflow flows through the battery housing 8.

  In step A5, the battery temperature T after the first cooling operation is compared with the second temperature T2, and it is determined whether or not the battery temperature T exceeds the second temperature T2. That is, it is determined whether or not sufficient cooling has been achieved with the cooling air volume and the cooling temperature by the first cooling operation. Here, if the battery temperature T does not exceed the second temperature T2, it is assumed that the battery unit 5 is sufficiently cooled only by the first cooling operation.

  On the other hand, when the battery temperature T exceeds the second temperature T2, the process proceeds to step A6 on the assumption that sufficient cooling cannot be performed only by the first cooling operation, and a compressor operation command is output. Then, the compressor 18 operates in step A7. When the compressor 18 operates, the refrigerant circulates between the heat exchanger 17 and the compressor 18, and the outside air from the outside air introduction path 13 is cooled by the heat exchanger 17 by the action of a known refrigeration cycle. For this reason, the airflow supplied to the battery storage unit 8 through the battery cooling outlet 15b and the duct 16 becomes a cooling airflow having a temperature lower than that of the blown airflow, and the battery storage unit 8 takes the heat of the battery unit 5 and exhausts it. It is discharged outside the vehicle by the fan 11. When such a cooling airflow circulates in the battery housing portion 8, the battery unit 5 is cooled more than when the blast airflow circulates.

  According to such a configuration, when the temperature T of the battery unit 5 at the time of rapid charging is higher than a predetermined temperature, the cooling unit 15 operates, so that the battery unit 5 that has generated heat by rapid charging can be cooled, The durability of the battery unit 5 can be improved as compared with the conventional case.

  In this embodiment, the first temperature T1 and the second temperature T2 (T1 <T2) are set as the predetermined temperatures, and the blower fan when the temperature T of the battery unit 5 at the time of quick charging is higher than the first temperature T1. 14 and the exhaust fan 11 are operated to drive the blower drive motor 141 and the discharge drive motor 111, and the temperature T of the battery unit 5 after the execution of the first cooling operation by the operation of these drive motors is the second temperature T2. When exceeding, the compressor 18 is additionally operated, so that the cooling capacity by the cooling means 15 is changed corresponding to the temperature change of the battery unit 5, and the effective battery unit 5 while suppressing excessive power consumption. Can be cooled, leading to improved charging efficiency.

  Further, when operating the exhaust fan 11 by driving the exhaust drive motor 111 in step A4, the air volume (number of rotations) by the exhaust fan 11 may be constant, but as shown in FIG. 4, the battery temperature T is high. The operation of the discharge drive motor 111 may be controlled so that the air volume (the number of rotations) of the discharge fan 11 is increased. When the discharge fan 11 is variably controlled in this way, the flow efficiency of the cooling airflow is improved, the battery unit 5 can be cooled more effectively, and the discharge drive motor 111 is not rotated at high speed immediately after the operation. Therefore, the durability of the discharge drive motor 111 is improved.

  Further, during normal charging that should not generate much heat, if the temperature T of the battery unit 5 is higher than a predetermined temperature, for example, the first temperature T1, there is a possibility that the vehicle has failed. Failure to perform cooling makes it possible to detect failures early.

  Further, in this embodiment, since the battery unit 5 is cooled only for a short time at the time of rapid charging, the durability required for the cooling means 15, particularly the discharge drive motor 111 does not change greatly, and the existing fan is used. Therefore, a significant increase in cost can be prevented, and the user's convenience is less likely to be lost due to the operating sound of the compressor 18 and the discharge drive motor 11 constituting the cooling means 15.

  FIG. 5 is a characteristic diagram showing the first and second temperatures and the operation timing of the cooling system. The exhaust drive motor 111 and the exhaust fan 11 constituting the air conditioning system operate when the battery temperature T exceeds the first temperature T1, and the compressor 18 operates when the battery temperature T exceeds the second temperature T2. However, the stop of the discharge drive motor 111 and the exhaust fan 11 and the stop of the compressor 18 are in an operating state until the battery temperature T becomes lower than the first temperature T1 and the second temperature T2, respectively. Assuming that the operation and stop temperatures are the same temperature, each drive motor or compressor is frequently operated / stopped due to temperature unevenness due to the mounting position of the temperature detection sensor 21 or an error due to a sensor insensitive body, resulting in durability. This is because there is an influence.

It is a schematic block diagram of the electric vehicle which is one Embodiment of this invention. It is a block diagram which shows the structure of the control system of this invention. It is a flowchart which shows one form of the battery cooling control by a control means. It is a diagram which occupies the operation characteristic by the air volume variable control of an exhaust fan. It is a figure which shows the operation timing of an air conditioning system and a compressor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric vehicle 2 Motor 3 Wheel 5 Power supply part 11 Exhaust fan 14 Blower fan 15 Air-conditioner unit 16 Duct 15 Cooling means 18 Compressor 21 Temperature detection means 101 Charging condition detection means 100 Control means 111 Discharge drive motor 121A External charger 141 Blast drive motor S Cooling airflow T Power supply temperature T1 First temperature T2 Second temperature

Claims (3)

A motor for driving the wheels; a cooling means for cooling the power supply of the motor; a temperature detection means for detecting a temperature state of the power supply; and detecting whether or not the power supply is being rapidly charged by an external charger. In an electric vehicle comprising a charging status detection means and a control means for controlling the cooling means,
The control means operates the cooling means when the temperature of the power supply unit at the time of rapid charging is higher than a predetermined temperature based on detection information from the temperature detection means and the charging status detection means. Electric car. The cooling means includes a blower driving motor that drives the blower fan and a compressor, and an air conditioner unit that generates a cooling airflow, and a discharge fan that discharges the cooling airflow supplied from the air conditioner unit to the power supply unit through a duct to the outside of the vehicle. Equipped with a discharge drive motor that drives
The control means should drive the blower fan and the exhaust fan when the temperature of the power supply unit at the time of rapid charging is higher than a first temperature based on detection information from the temperature detection means and the charging status detection means. The blower drive motor and the discharge drive motor are operated, and when the temperature of the power supply unit at the time of the quick charge is a second temperature higher than the first temperature, the compressor is additionally operated. Item 1. An electric vehicle according to Item 1.   The electric vehicle according to claim 2, wherein the control means controls the operation of the discharge drive motor such that the rotation of the discharge fan increases as the temperature of the power supply unit increases.

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