Vehicle air conditioning system

Abstract

To provide an air conditioner for a vehicle, that rotates a compressor at a rotation frequency with high energy consumption efficiency, in order to suppress power consumption of the compressor and prevent electric power from being wastefully consumed, when time to completion of battery charging is long in executing pre-air-conditioning during charging of the battery.SOLUTION: Provided is an air conditioner 20 for a vehicle, that has a pre-air-conditioning function for air conditioning inside a cabin before a user boards a vehicle 10. When pre-air-conditioning is executed during charging of a vehicular battery 30, the air conditioner implements pre-air-conditioning using a rotation frequency of an air-conditioning compressor 26 at which energy consumption efficiency of the compressor 26 is maximized, as an upper limit value, if time to charging completion of the battery 30 is equal to a prescribed time or longer.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a vehicle air conditioning device having a pre-air conditioning function for conditioning an interior of a vehicle before a user gets into the vehicle. [Background technology]

[0002] A pre-air conditioning system is known that pre-conditions the interior of a vehicle before a user gets into the vehicle. In the pre-air conditioning system, a defroster for clearing fog on the windshield and a heater for pre-heating the interior of the vehicle can be operated.

[0003] In vehicles such as electric vehicles and hybrid vehicles that use battery power as a driving source, the power consumed by the air conditioner used for pre-air conditioning is supplied from the battery or from a power source outside the vehicle (external power source) connected to the vehicle to charge the battery.

[0004] Patent Document 1 describes a vehicle air conditioner that performs pre-air conditioning before a user gets into the vehicle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-212809 A Summary of the Invention [Problem to be solved by the invention]

[0006] While the battery is being charged, it is considered that the user will not immediately get into the vehicle. If pre-air conditioning is performed when it will take a long time to finish charging the battery, the air conditioning compressor may rotate at high speed even though the user will not immediately get into the vehicle, which increases power consumption and results in unnecessary power consumption.

[0007] The object of the present disclosure is to provide a vehicle air conditioning system that, when performing pre-air conditioning while the battery is charging, can reduce the power consumption of the compressor and prevent unnecessary power consumption by rotating the compressor at a rotation speed that has high energy efficiency if there is a long time left until the battery charging is completed. [Means for solving the problem]

[0008] The vehicle air conditioning system disclosed herein has a pre-air conditioning function that conditions the interior of the vehicle before a user gets into the vehicle, and is characterized in that when pre-air conditioning is performed while the vehicle battery is charging, if the time remaining until charging of the battery is completed is equal to or longer than a predetermined time, pre-air conditioning is performed by setting the rotation speed of the air conditioning compressor to an upper limit value of the rotation speed at which the compressor's energy consumption efficiency is maximized. Effect of the Invention

[0009] The vehicle air conditioning system of the present disclosure, when charging the vehicle battery while pre-air conditioning is being performed, performs pre-air conditioning with the rotation speed of the compressor for pre-air conditioning set to the upper limit value of the rotation speed at which energy consumption efficiency is maximized if the vehicle battery is charged while pre-air conditioning is being performed and there is a long period of time until battery charging is completed. This reduces power consumption by the compressor and prevents unnecessary power consumption. [Brief description of the drawings]

[0010] [Figure 1] 1 is a configuration diagram of a vehicle according to an embodiment. [Diagram 2] 1 is a configuration diagram of a vehicle air conditioning device according to an embodiment; [Diagram 3] FIG. 4 is a diagram showing the relationship between the energy consumption efficiency and the rotation speed of a compressor. [Figure 4] 4 is an operation flowchart of an air conditioner ECU according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. In the following description, specific shapes, materials, directions, values, etc. are examples for facilitating understanding of the present disclosure, and can be appropriately changed according to applications, purposes, specifications, etc. In addition, it is initially assumed that the components of the embodiments and modified examples described below can be selectively combined.

[0012] 1 is a configuration diagram of a vehicle 10 according to an embodiment. The vehicle 10 is an electric vehicle that runs on a motor (not shown) driven by power supplied from a battery 30. The battery 30 also operates as a power supply source for each device of the vehicle 10.

[0013] The vehicle 10 according to this embodiment includes a vehicle air conditioner 20, a battery 30, a charging port 40, a charging control ECU 50, and a DCM 60.

[0014] The vehicle air conditioner 20 is a device that conditions the air inside the vehicle cabin by applying the principle of a heat pump that combines the compression and expansion of a refrigerant with heat exchange. The vehicle air conditioner 20 has an air conditioner ECU 21 that controls the air conditioning, a compressor 26 that compresses the refrigerant, an evaporator 27 as a heat exchanger, a condenser 28, and an expansion valve 29 (see FIG. 2), and is controlled by the air conditioner ECU 21. Each device, including the compressor 26, is supplied with power from a battery 30.

[0015] A charging connector 120 is connected to the charging port 40 , and power is supplied from an external power source 100 via a charging cable 110 .

[0016] The charging device 41 is connected between the charging port 40 and the battery 30, converts AC power supplied from the external power source 100 into DC power, and charges the battery 30.

[0017] The charging control ECU 50 has a function of monitoring the charging state of the battery 30. In this embodiment, the charging control ECU 50 has a charging determination unit 51 that detects the state of the charging port 40 and determines whether the battery 30 is being charged, and a charging time determination unit 52 that detects the states of the charging device 41 and the battery 30 and determines the time remaining until charging of the battery 30 is completed. The determination results of the charging determination unit 51 and the charging time determination unit 52 are transmitted to the air conditioner ECU 21.

[0018] The DCM (Data Communication Module) 60 is a communication device capable of wireless communication with the outside of the vehicle. In this embodiment, the DCM 60 has a function of receiving an operation instruction for pre-air conditioning from a user's smartphone 70 and transmitting the operation instruction for pre-air conditioning to the air conditioner ECU 21.

[0019] Here, ECUs (Electronic Control Units) such as the air conditioner ECU 21 and the charge control ECU 50 each have a built-in CPU (Central Processing Unit) and memory (not shown). The ECU has the role of controlling each device of the vehicle 10 based on information stored in the memory and information from various sensors (not shown). In this embodiment, only the air conditioner ECU 21 and the charge control ECU 50 are shown. The vehicle 10 is also equipped with ECUs having functions other than these, but these are omitted.

[0020] Before getting into the vehicle, the user can operate the smartphone 70 to pre-air-condition the vehicle 10.

[0021] Next, the pre-air conditioning control in the vehicle air conditioner 20 of this embodiment will be described.

[0022] 2 shows the configuration of the vehicle air conditioner 20. The vehicle air conditioner 20 is made up of an air conditioner ECU 21 that executes air conditioning control, and devices such as a compressor 26 that are controlled by the air conditioner ECU 21.

[0023] The air conditioner ECU 21 has a pre-air conditioning execution unit 22, a temperature determination unit 23, a normal control unit 24, and an energy saving control unit 25. Each of these units is realized by a program stored in a memory built into the air conditioner ECU 21 and executed by the CPU.

[0024] The air conditioner ECU 21 receives various data for executing air conditioning control. The air conditioner ECU 21 receives an operation command for pre-air conditioning from the DCM 60. Furthermore, the air conditioner ECU 21 receives battery charging information from the charge control ECU 50, and receives the vehicle interior temperature and the vehicle exterior temperature from the temperature sensor 80. The air conditioner ECU 21 executes pre-air conditioning based on the received data through processing by each unit of the air conditioner ECU 21.

[0025] The pre-air conditioning execution unit 22 executes and stops pre-air conditioning. Specifically, the pre-air conditioning is executed upon receiving an operation command of the pre-air conditioning from the DCM 60. The conditions for stopping the pre-air conditioning are not limited in the present disclosure, but for example, the pre-air conditioning is configured to be stopped when the execution time of the pre-air conditioning has elapsed for a certain period of time or more.

[0026] The temperature determination unit 23 determines the vehicle interior temperature and the vehicle exterior temperature from the temperature sensor 80. The temperature determination result is used to control the compressor 26, which will be described later, specifically to determine the rotation speed of the compressor 26.

[0027] The air conditioner ECU 21 switches between the normal control unit 24 and the energy saving control unit 25 to perform control depending on the charging information of the battery 30 received from the charging control ECU 50. Specifically, the air conditioner ECU 21 switches the control of the rotation speed of the compressor 26.

[0028] When information is received from the charging control ECU 50 that the battery 30 is not being charged, the normal control unit 24 determines and controls the rotation speed of the compressor 26. On the other hand, when information is received from the charging control ECU 50 that the battery 30 is being charged and the time remaining until charging is completed is longer than a predetermined time, the energy saving control unit 25 determines and controls the rotation speed of the compressor 26.

[0029] Normally, the control unit 24 determines the rotation speed of the compressor 26 so that the vehicle interior temperature becomes the target set temperature of the pre-air conditioning. When there is a large difference between the vehicle interior temperature and the target set temperature, the compressor 26 rotates at maximum power (maximum rotation speed).

[0030] Here, the compressor 26 is a device that compresses the refrigerant to a high temperature and pressure. The compressor 26 is driven by a motor, and the faster it rotates, the higher the heat exchange becomes possible. Meanwhile, the energy consumption efficiency of the compressor 26 reaches a maximum value COPmax at a rotation speed T0 specific to the compressor 26, and the energy consumption efficiency tends to decrease around the rotation speed T0 (see FIG. 3). Therefore, when there is a large temperature difference between the temperature inside the vehicle cabin and the target set temperature, or when the defroster mode is set, the control by the normal control unit 24 executes pre-air conditioning at a rotation speed higher than the rotation speed T0, resulting in a low energy consumption efficiency.

[0031] When charging the battery, the vehicle is usually used after the battery is fully charged. Therefore, if it takes a long time to complete charging the battery, it is considered that the user will not get into the vehicle for a while. In this case, if pre-air conditioning is performed by the normal control unit 24 even though the vehicle is not being used, the compressor 26 may be operated at a rotation speed higher than the rotation speed T0, which may result in unnecessary consumption of power. Furthermore, if the charging power is used for pre-air conditioning, the time until charging is completed will also be longer.

[0032] In the vehicle air conditioner 20 of this embodiment, as described above, when it is determined that the battery 30 is being charged and the time until the end of charging is longer than a predetermined time, the energy saving control unit 25 determines and controls the rotation speed of the compressor 26. Specifically, the energy saving control unit 25 determines the rotation speed so that the compressor 26 operates with the rotation speed T0 at which the energy consumption efficiency specific to the compressor 26 is maximized as the upper limit. More specifically, the energy saving control unit 25 controls the upper limit of the rotation speed of the compressor 26 to be lower than when the time until the end of charging of the battery 30 is shorter than a predetermined time. In a situation where the time until the end of charging is long, it is not necessary to rapidly adjust the temperature inside the vehicle cabin to the target set temperature by pre-air conditioning, so that the power consumption by pre-air conditioning can be reduced by controlling the compressor 26 by the energy saving control unit 25.

[0033] The charging state of the battery 30 is detected as follows. Whether or not the battery 30 is being charged is detected by the charging determination unit 51 of the charging control ECU 50 monitoring the state of the charging port 40. The charging time determination unit 52 of the charging control ECU 50 calculates the time until charging of the battery 30 is completed from the charge amount of the charging device 41 and the remaining battery capacity of the battery 30. The calculated time until charging of the battery 30 is completed is transmitted to the air conditioner ECU 21.

[0034] The air conditioner ECU 21, which has received the time remaining until the end of charging the battery 30 from the charging control ECU 50, executes pre-air conditioning by using the energy saving control unit 25 to set the rotation speed of the compressor 26 to the rotation speed T0 at which the energy consumption efficiency is maximized as the upper limit value if the time remaining until the end of charging is equal to or longer than a predetermined time. This makes it possible to execute pre-air conditioning without wasting electricity.

[0035] The control of the pre-air conditioning of the vehicle air conditioner 20 of this embodiment will be described with a specific example.

[0036] When pre-AC is performed, the temperature inside the vehicle cabin reaches the target temperature in about 10 to several tens of minutes, depending on the temperature inside the vehicle cabin and the temperature outside the vehicle. Therefore, the time required for pre-AC is on the order of several tens of minutes. In the control of pre-AC by the normal control unit 24, the compressor 26 is operated at the maximum rotation speed according to the target temperature in order to rapidly reach the temperature inside the vehicle cabin to the target temperature.

[0037] The time required to charge the battery 30 varies depending on the remaining charge of the battery 30 at the start of charging and the charging capacity of the charging device 41, but generally requires several hours. Therefore, the time required to charge the battery 30 is several to several dozen times longer than the time required for pre-air conditioning.

[0038] Let us consider a case where it takes several hours to finish charging the battery 30. Here, let us assume that the user issues a command from the smartphone 70 to start pre-air conditioning.

[0039] As described above, even if the temperature reaches the set temperature for pre-AC by normal control, charging of the battery 30 does not end. Therefore, the vehicle is not used and pre-AC continues to maintain the temperature inside the vehicle, resulting in unnecessary consumption of power. Moreover, when the defroster mode or heating mode is set, the compressor 26 rotates at close to the maximum rotation speed of the output setting, consuming a lot of power and operating in a state of low energy consumption efficiency.

[0040] Therefore, when the vehicle air conditioner 20 of this embodiment detects that the battery 30 is being charged and determines that it will take a predetermined time (e.g., one hour) or more until charging is completed, it controls the compressor 26 so that the rotation speed of the compressor 26 is set to an upper limit value of the rotation speed T0 corresponding to the maximum energy consumption efficiency, specifically, so that the upper limit value of the rotation speed of the compressor 26 is lowered compared to when the time until charging of the battery 30 is completed is less than the predetermined time.

[0041] In the pre-air conditioning of the vehicle air conditioner 20 of this embodiment, unnecessary energy consumption by the compressor 26 is suppressed. Furthermore, when the vehicle is not being used because the battery is being charged, air conditioning (cooling or heating) of the vehicle interior is not performed more quickly than necessary, thereby reducing power consumption. In addition, because power is not used more than necessary for pre-air conditioning, the battery is quickly charged.

[0042] Next, a flowchart of the operation of the air conditioner ECU 21 will be described with reference to FIG.

[0043] When a user issues an instruction to perform pre-air conditioning via the smartphone 70, the air conditioner ECU 21 receives an operation instruction for pre-air conditioning from the DCM 60, and the pre-air conditioning execution unit 22 starts the pre-air conditioning.

[0044] Next, the air conditioner ECU 21 determines whether the battery 30 is being charged based on the charging information from the charging control ECU 50 (step S1). If it is determined that the battery 30 is not being charged, the normal control unit 24 operates the compressor 26 at a rotation speed determined for the target temperature in order to perform pre-air conditioning under normal control (step S3).

[0045] If it is determined in step S1 that the battery 30 is being charged, it is determined whether the time remaining until the end of charging the battery 30 is longer than a predetermined time (e.g., one hour) based on the charging information from the charging control ECU 50 (step S2). If it is determined that the time remaining until the end of charging the battery 30 is equal to or shorter than the predetermined time, the normal control unit 24 operates the compressor 26 at a rotation speed determined for the target temperature (step S3).

[0046] If it is determined in step S2 that the time remaining until charging of the battery 30 is completed is longer than the predetermined time, the air conditioner ECU 21 causes the energy saving control unit 25 to operate the compressor 26 (step S4). As described above, the energy saving control unit 25 controls the compressor 26 to operate at a rotation speed whose upper limit is the rotation speed T0 at which the energy consumption efficiency of the compressor 26 is maximized.

[0047] It should be noted that the present disclosure is not limited to the above-described embodiment and its modified examples, and various modifications and improvements are possible within the scope of the matters described in the claims of the present application. [Explanation of symbols]

[0048] 10 vehicle, 20 vehicle air conditioner, 21 air conditioner ECU, 22 pre-air conditioning execution unit, 23 temperature determination unit, 24 normal control unit, 25 energy saving control unit, 26 compressor, 27 evaporator, 28 condenser, 29 expansion valve, 30 battery, 40 charging port, 41 charging device, 50 charging control ECU, 51 charging determination unit, 52 charging time determination unit, 60 DCM, 70 smartphone, 80 temperature sensor, 100 external power source, 110 charging cable, 120 charging connector

Claims

[Claim 1] A vehicle air conditioning device having a pre-air conditioning function for conditioning a vehicle interior before a user gets into the vehicle, the vehicle has a charging device that converts AC power supplied from an external power source into DC power to charge a vehicle battery; When the pre-air conditioning is performed while the battery is being charged, the time until the charging of the battery is completed by the charging device is calculated from the charge amount per unit time of the charging device and the remaining charge of the battery, and if the time until the charging of the battery is completed is equal to or longer than a predetermined time, the pre-air conditioning is performed with the rotation speed of the air conditioning compressor set to an upper limit value equal to the rotation speed at which the energy consumption efficiency of the compressor is maximized. Vehicle air conditioning system.

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