JP2018034568A - Air conditioner of electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner of a vehicle which can inhibit addition of new components and adjust an air temperature of a vehicle cabin even in a harsh temperature environment by utilizing a temperature difference between the vehicle cabin and an area below a luggage compartment board.SOLUTION: An air conditioner of an electric vehicle is mounted on an electric vehicle having a driving motor (8), a battery (20), a battery fan (21), a charger (10), and a luggage compartment (5) in which a bottom part is partitioned by a luggage compartment board (4). The air conditioner further includes: a charger arrangement part (10A) provided below the luggage compartment board (4); an intake passage leading from the outside of the electric vehicle to the arrangement part (10A); an air duct (13) leading from the arrangement part (10A) to a vehicle cabin (9) of the electric vehicle; and a charger fan (11) which can be driven independently from the battery fan (21) and cools the charger (10). The charger fan (11) is configured to send air that cools the charger (10) to the vehicle cabin (9) through the air duct (13).SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air conditioner for an electric vehicle.

  The passenger compartment of an automobile may become a severe temperature such as 60 ° C. to 70 ° C. when it is parked under the hot summer sun. In particular, it may exceed 70 ° C in seasons or areas with strong sunlight. Also, in extremely cold regions and seasons, the passenger compartment of an automobile can be as low as -40 ° C.

  Usually, an automobile is equipped with an air conditioner that cools and heats a passenger compartment using a refrigerant. However, the air conditioning apparatus using a refrigerant has an air conditioning capacity that varies depending on the environmental temperature. The automobile is also equipped with an air conditioner that heats the passenger compartment using high-temperature engine cooling water. However, the engine coolant does not become hot unless the engine is started. For this reason, in a severe temperature environment, even if an automobile air conditioner is started, a rapid cooling or heating capability may not be obtained.

  Conventionally, when the passenger compartment is at a harsh temperature, the occupant can open the window to ventilate when it is hot, or install an electric heater when it is cold to reach a temperature that can enter the passenger compartment. I had to wait in another place until it was.

  In addition, as a related art related to the present invention, Patent Documents 1 to 3 describe that in an electric vehicle equipped with a battery that is a power source for a motor for traveling, the blast of a cooling fan for the battery is sent to the passenger compartment, Techniques for assisting room heating and cooling are shown.

JP 2013-224105 A JP 2010-047222 A JP 2005-262897 A

  The present inventors examined whether this could be quickly resolved when the passenger compartment reached a severe temperature. It is important to note that the temperature below the cargo compartment partitioned by the cargo compartment board may be maintained at a relatively moderate temperature even in an environment where the passenger compartment is at a severe temperature during the examination process. The inventors have found.

  From such a viewpoint, it is considered that the severe temperature of the passenger compartment can be relaxed by sending air from the space below the cargo compartment board to the passenger compartment using the techniques of Patent Literature 1 to Patent Literature 3. It was. Specifically, a battery is arranged in a space below the cargo compartment board, and air below the cargo compartment board is sent to the passenger compartment by the battery cooling fan.

  In the field of automobiles, the addition of new parts necessitates securing a mounting space for parts, which further increases the part cost. Therefore, if other parts can be used to obtain the same function, it is preferable that no new parts be added.

  However, the configuration in which the air below the cargo compartment board is sent to the passenger compartment using the battery cooling fan cannot be used to reduce the temperature in a situation where the passenger compartment is at a severe temperature. There was found. This is because the battery has a working temperature range for preventing major deterioration. In an environment where the passenger compartment is at a severe temperature, operating the cooling fan often moves the battery temperature away from the operating temperature range. Therefore, in such a temperature environment, the battery cooling fan cannot be driven in many cases.

  The present invention is a vehicle that can suppress the addition of new parts and can adjust the temperature of the passenger compartment by using the temperature difference between the passenger compartment and the lower part of the cargo compartment board even in a severe temperature environment. An object is to provide an air conditioner.

The invention described in claim 1
A traveling motor; a battery that supplies power to the traveling motor; a battery fan that cools the battery; a charger that outputs a charging current to the battery; and a luggage compartment that is partitioned by a cargo board. An air conditioner for an electric vehicle mounted on an electric vehicle having
An arrangement portion of the charger provided below the cargo compartment board;
An intake passage leading from the outside of the electric vehicle to the placement portion;
An air duct leading from the placement section to a passenger compartment of the electric vehicle;
A charger fan that can be driven independently of the battery fan and cools the charger;
With
The charger fan is configured to send air for cooling the charger to the passenger compartment through the air duct.

According to a second aspect of the present invention, in the air conditioner for an electric vehicle according to the first aspect,
The arrangement part is adjacent to a battery housing part in which the battery is housed,
A part of the intake passage is in contact with the battery accommodating portion.

According to a third aspect of the present invention, in the air conditioner for an electric vehicle according to the first or second aspect,
A temperature sensor for detecting a temperature below the cargo compartment board;
A signal input unit for inputting a signal of the temperature of the passenger compartment;
A controller for driving the charger fan;
With
The control unit drives the charger fan based on a signal from the temperature sensor and a signal input to the signal input unit during a period when the charger does not operate.

According to a fourth aspect of the present invention, in the air conditioner for an electric vehicle according to the third aspect,
The controller is configured to switch the charger fan when there is a temperature difference equal to or greater than a predetermined threshold between the lower part of the cargo compartment board and the passenger compartment and the lower part of the cargo compartment board is closer to the standard temperature. It is characterized by driving.

  According to the air conditioner for an electric vehicle of the present invention, the arrangement portion of the charger is provided below the cargo compartment board, and further, the air duct leading from the arrangement portion to the passenger compartment is provided. Therefore, the air at a moderate temperature below the cargo compartment board can be sent to the passenger compartment via the air duct by the charger fan. The driving conditions of the charger fan are significantly less limited than the driving conditions of the battery fan. Therefore, the charger fan can be driven even in a temperature environment where the passenger compartment is at a severe temperature and the battery fan cannot be driven. Therefore, according to the air conditioner for an electric vehicle of the present invention, it is possible to adjust the temperature of the passenger compartment using the temperature difference between the passenger compartment and the lower part of the cargo compartment board while suppressing the addition of new parts. it can.

It is the schematic which shows the electric vehicle carrying the air conditioner of embodiment which concerns on this invention. It is a block diagram which shows the control system of the air conditioner of FIG. It is a graph which shows the drive condition of a battery fan. It is a flowchart which shows an example of the procedure of a charger fan drive process.

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

  FIG. 1 is a schematic diagram showing an electric vehicle equipped with an air conditioner according to an embodiment of the present invention. FIG. 2 is a block diagram showing a control system of the air conditioner.

  The electric vehicle 1 on which the air conditioner of this embodiment is mounted is an electric vehicle (EV) capable of running on electricity, a hybrid electric vehicle (HEV), or the like. The electric vehicle 1 includes a charging port 2, an air conditioner 3, a cargo compartment board 4, a cargo compartment 5, a cargo compartment lower space 6, a traveling motor 8, a passenger compartment 9, a charger 10, an air duct 13, and a battery 20. .

  The charging port 2 is a device to which a charging connector (charging gun, charging flag, etc.) can be connected from the outside of the electric vehicle 1. The charging port 2 and the charger 10 are connected via a cable. Charging power can be sent from the external power source to the charger 10 via the charging port 2.

  The air conditioner 3 is a device that cools and heats the passenger compartment 9 using a refrigerant, and includes an air conditioner ECU (electronic control unit) 3A that performs air conditioning control as shown in FIG. The air conditioner ECU 3 </ b> A can acquire temperature information of the passenger compartment 9 by inputting a signal from the temperature sensor of the passenger compartment 9.

  The cargo compartment board 4 is a plate material that partitions the bottom of the cargo compartment 5 at the rear of the electric vehicle.

  The luggage compartment 5 is a space where luggage is placed, and is provided behind the passenger compartment 9. In the present embodiment, a configuration in which the cargo compartment 5 and the passenger compartment 9 communicate with each other is employed, but the cargo compartment 5 may be shielded from the passenger compartment 9. In this case, an exhaust port 13 a of the air duct 13 described later may be provided so as to open into the passenger compartment 9.

  In the cargo space 6, a charger 10, a suspension mechanism, a part of a power transmission device, and the like are arranged. The lower surface of the cargo space 6 may be covered with an under panel. With such a configuration, a number of air passages that lead from the lower side of the electric vehicle 1 to the outside from the placement portion 10A of the charger 10 to between the members of each mechanism and the opening portion of the under panel, etc. Is formed.

  The traveling motor 8 rotationally drives the wheels of the electric vehicle 1 through a power transmission device.

  The battery 20 is a secondary battery such as a large capacity lithium ion battery. The battery 20 has a plurality of cells connected in series, and can output high-current and high-power power to the traveling motor 8 through an inverter circuit or the like. The battery 20 has a characteristic of generating heat during charging and discharging. The battery 20 is accommodated in, for example, a battery accommodating portion 20A provided below the cargo space 6 and the passenger compartment.

  A battery fan 21 is further attached to the battery 20. As shown in FIG. 2, the electric vehicle 1 is provided with a battery fan control unit 25, a battery temperature sensor 26, and an intake air temperature sensor 27. The battery fan 21 and these components may be configured as a unit with the battery 20.

  The battery fan 21 is a fan that cools a plurality of cells of the battery 20. The battery temperature sensor 26 detects the temperature of a plurality of cells and outputs a battery temperature signal indicating this temperature to the battery fan control unit 25. The intake air temperature sensor 27 detects the temperature of the air around the battery 20 that serves as intake air for the battery fan 21, and outputs an intake air temperature signal indicating this temperature to the battery fan controller 25. The battery fan control unit 25 is a control circuit, and drives or stops the battery fan 21 based on these signals.

  The charger 10 charges the battery 20 with the electric power supplied from the charging port 2. The charger 10 monitors and controls the charging current and charging voltage of the battery 20. Depending on the type of external power source that can be used, the charger 10 may include a converter circuit that converts the voltage of the external power source input from the charging port 2 into a charging voltage. The charger 10 includes a circuit having a power semiconductor, and drives the power semiconductor to control a large charging current with a high voltage. For this reason, the circuit of the charger 10 has a property of generating heat during charging. The charger 10 is attached to an arrangement portion 10 </ b> A provided in the cargo space 6.

  A charger fan 11 is further attached to the charger 10. Further, as shown in FIG. 2, the electric vehicle 1 is provided with a charger fan control unit 15 and a temperature sensor 12. The charger fan 11 and these components may be unitized with the charger 10. The charger fan control unit 15 corresponds to an example of a control unit according to the present invention.

  The charger fan 11 is a fan that cools the charger 10. The temperature sensor 12 is a sensor (for example, a thermistor) that detects the temperature below the cargo compartment board 4. The charger fan control unit 15 includes a plurality of signal input units 15a to 15c, a temperature signal from the temperature sensor 12, an operation signal indicating that charging is being performed from the charger 10, and an air conditioner ECU 3A. A passenger compartment temperature signal indicating the temperature of the passenger compartment is input. The charger fan control unit 15 is a control circuit, and drives or stops the charger fan 11 based on these signals.

  The air duct 13 is a duct that communicates between the cargo space 6 and the passenger compartment 9. The air inlet of the air duct 13 is provided so that the wind pressure of the charger fan 11 is applied. Such a configuration can be easily realized, for example, by configuring the charger fan 11 with a sirocco fan and providing the charger fan 11 in the middle of the air duct 13. An exhaust port 13 a of the air duct 13 is open to the cargo compartment 5 that leads to the passenger compartment 9.

  The air conditioner of the electric vehicle 1 according to the present embodiment includes the charger fan 11, the air duct 13, the arrangement portion 10 </ b> A that communicates with the air duct 13, the intake passage of the cargo space 6, the charger fan control unit 15, among the configurations described above. And a component including the temperature sensor 12.

<Description of operation>
In the present embodiment, the battery fan 21 is driven or stopped under the control of the battery fan control unit 25.

  FIG. 3 is a graph showing driving conditions of the battery fan. As shown in FIG. 3, the battery fan 21 is driven in a limited temperature environment based on the cell temperature of the battery 20 (referred to as “battery temperature” in the figure) and the intake air temperature. By such drive control, it is possible to avoid a temperature at which the battery 20 is greatly deteriorated. Therefore, for example, in a situation where the passenger compartment 9 becomes extremely hot due to parking under the hot sun, while the space 6 under the cargo compartment is kept at a relatively moderate temperature, the battery fan 21 is driven by the above-described restriction. There are many cases where this is not possible.

  On the other hand, the charger fan control unit 15 drives or stops the charger fan 11 independently of the battery fan 21 by the charger fan driving process.

  FIG. 4 is a flowchart illustrating an example of the procedure of the charger fan driving process. This drive control is repeatedly executed by the charger fan control unit 15 after the system startup of the electric vehicle 1, for example, every short cycle. The system startup of the electric vehicle 1 means a state in which the power supply voltage is supplied to the main ECU of the electric vehicle 1, for example, after the power switch is turned on.

  When the driving process is started, the charger fan control unit 15 determines whether the charger 10 is operating (step S1). As a result of the determination, if it is operating, the process proceeds to step S6, and the charger fan 11 is driven (step S6). If the charger fan 11 is already being driven in step S6, the charger fan control unit 15 continues this drive.

  On the other hand, if the charger 10 is not operating as a result of the determination in step S1, the charger fan control unit 15 determines that the passenger compartment 9 and the passenger compartment lower space based on the cargo compartment board lower temperature signal and the passenger compartment temperature signal. A temperature difference Tdiff from 6 is calculated (step S2). Further, the charger fan control unit 15 calculates a difference T1 between the temperature of the passenger compartment 9 and a predetermined standard temperature, and a difference T2 between the temperature of the cargo space 6 and the predetermined standard temperature (step S3, S4). The standard temperature means the standard temperature in the room that people feel comfortable with.

  Next, the charger fan control unit 15 determines whether or not the temperature difference Tdiff is equal to or greater than a predetermined threshold and the differences T1 and T2 from the standard temperature are larger in the passenger compartment 9 (step S5). As a result, if YES, the charger fan control unit 15 drives the charger fan 11 (step S6), and if NO, stops the charger fan 11 (step S7). If the charger fan 11 is already being driven in step S6, the charger fan control unit 15 continues this drive. When the charger fan 11 is already stopped in step S7, the charger fan control unit 15 continues this stop.

  When the process of step S6 or step S7 is executed, one charger fan drive process is completed, and the charger fan drive process is started again in the next cycle.

  According to such a control process, for example, when the electric vehicle 1 is system-started in a situation where the passenger compartment 9 is in a severe temperature due to parking under a hot sun and the cargo space 6 is maintained at a moderate temperature. Even if the charger 10 is not operating, the charger fan 11 is driven. When the charger fan 11 is driven, air having a moderate temperature under the cargo space 6 is sent to the passenger compartment 9. In addition, air is sucked from the lower side of the electric vehicle 1 using the above-described air passage provided in the lower cargo space 6 as an intake air passage, and this air comes into contact with the mechanism of the lower cargo space 6 to reach a moderate temperature. And sent to the passenger compartment 9. In FIG. 1, such an air flow is indicated by white arrows. Due to such air flow, the severe temperature of the passenger compartment 9 is relaxed relatively quickly.

  Further, in a situation where the temperature of the passenger compartment 9 is very low in a cold region, and the battery 20 generates heat due to power consumption or charging of the battery 20, the temperature of the cargo space 6 is lower than that of the passenger compartment. Compared to 9, the temperature is moderate. According to the above control process, in such a case, the charger fan 11 is driven even if the charger 10 is not operating. When the charger fan 11 is driven, air having a moderate temperature under the cargo space 6 is sent to the passenger compartment 9. In addition, air is sucked by using the above-described air passage provided in the cargo space 6 as an intake passage, and the air flowing along the battery accommodating portion 20A is warmed by the exhaust heat of the battery 20 to a moderate temperature. And sent to the passenger compartment 9. And the severe temperature of the passenger | crew compartment 9 is relieve | moderated comparatively rapidly by such a flow of air.

  As described above, according to the air conditioner for an electric vehicle according to the present embodiment, the placement portion 10A of the charger 10 is provided below the cargo compartment board 4, and the air duct 13 that leads from the placement portion 10A to the passenger compartment 9 is provided. Is provided. Therefore, in a situation where the temperature of the passenger compartment 9 is severe, the charger fan 11 can send air having a moderate temperature to the passenger compartment 9 via the air duct 13. Since the driving condition of the charger fan 11 is significantly less limited than the driving condition of the battery fan 21, the charger fan 11 can be driven even in a temperature environment where the battery fan 21 cannot be driven. Therefore, the temperature of the passenger compartment 9 can be adjusted using the temperature difference between the passenger compartment 9 and the cargo space 6 while suppressing the addition of new parts.

  Further, according to the air conditioner for an electric vehicle of the present embodiment, the arrangement unit 10A of the charger 10 is adjacent to the battery housing unit 20A, and a part of the intake passage of the charger fan 11 is in contact with the battery housing unit 20A. It is configured. For this reason, when the battery 20 is generating heat by discharging or charging the battery 20, the air warmed by the generated heat can be sent to the passenger compartment 9 by driving the charger fan 11. Therefore, when the passenger compartment 9 has a very low temperature, the low temperature of the passenger compartment 9 can be relaxed by the warmed air.

  Moreover, according to the air conditioner for an electric vehicle according to the present embodiment, the charger fan control unit 15 is based on the temperature of the passenger compartment 9 and the temperature of the cargo space 6 during the period when the charger 10 does not operate. The drive of the fan 11 is controlled. Furthermore, when there is a temperature difference between the passenger compartment 9 and the cargo space 6 below the threshold value and the cargo space 6 is closer to the standard temperature, the charger fan control unit 15 is connected to the charger fan 11. Drive driving. Therefore, the charger fan 11 can be driven effectively in a situation where the temperature difference between the passenger compartment 9 and the cargo space 6 can be relaxed using the temperature difference between the passenger compartment 9 and the cargo space 6.

  The embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment. For example, in the present embodiment, the charger 10 has been described as a configuration that charges the battery 20 based on an external power source input via the charging port 2. However, the charger according to the present invention may be configured to charge the battery 20 with regenerative energy when the electric vehicle 1 is braked. The charger according to the present invention may be configured to charge the battery 20 with the kinetic energy of the engine in a hybrid electric vehicle equipped with an engine. In such a configuration, even when the passenger compartment 9 is at an appropriate temperature, the charger 10 may be activated to drive the charger fan 11 when the electric vehicle 1 is operated. For this reason, the air duct 13 is configured to be openable and configured so that when the temperature of the passenger compartment 9 is appropriate when the charger 10 is operated, the air duct 13 is closed and the air blown by the charger fan 11 is discharged to the other. Also good.

  Moreover, in the said embodiment, 20 A of battery accommodating parts were provided in the position adjacent to the arrangement | positioning part 10A of the charger 10. FIG. However, the battery housing portion 20 </ b> A may be provided apart from the charger 10. In addition, the details shown in the embodiments can be appropriately changed without departing from the spirit of the invention.

1 Electric Vehicle 2 Charging Port 3 Air Conditioner 3A Air Conditioner ECU
DESCRIPTION OF SYMBOLS 4 Cargo board 5 Cargo compartment 6 Cargo space 8 Driving motor 9 Passenger room 10 Charger 10A Arrangement part 11 Charger fan 12 Temperature sensor 13 Air duct 13a Exhaust port 15 Charger fan control part 15a-15c Signal input part 20 Battery 20A Battery housing part 21 Battery fan 25 Battery fan control part

Claims (4)

A traveling motor; a battery that supplies power to the traveling motor; a battery fan that cools the battery; a charger that outputs a charging current to the battery; and a luggage compartment that is partitioned by a cargo board. An air conditioner for an electric vehicle mounted on an electric vehicle having
An arrangement portion of the charger provided below the cargo compartment board;
An intake passage leading from the outside of the electric vehicle to the placement portion;
An air duct leading from the placement section to a passenger compartment of the electric vehicle;
A charger fan that can be driven independently of the battery fan and cools the charger;
With
The air conditioner for an electric vehicle, wherein the charger fan is configured to send air for cooling the charger to the passenger compartment through the air duct. The arrangement part is adjacent to a battery housing part in which the battery is housed,
The air conditioner for an electric vehicle according to claim 1, wherein a part of the intake passage is in contact with the battery housing portion. A temperature sensor for detecting a temperature below the cargo compartment board;
A signal input unit for inputting a signal of the temperature of the passenger compartment;
A controller for driving the charger fan;
With
The said control part drives the said charger fan based on the signal input into the signal of the said temperature sensor and the said signal input part during the period when the said charger does not operate | move. 3. An air conditioner for an electric vehicle according to 2.   The controller is configured to switch the charger fan when there is a temperature difference equal to or greater than a predetermined threshold between the lower part of the cargo compartment board and the passenger compartment and the lower part of the cargo compartment board is closer to the standard temperature. The air conditioner for an electric vehicle according to claim 3, wherein the air conditioner is driven.

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