JP6845783B2 - Vehicle air conditioner and control method of vehicle air conditioner - Google Patents

Description

The present invention relates to a vehicle air conditioner and a method for controlling a vehicle air conditioner.

An air conditioner mounted on a vehicle such as an automobile (hereinafter, also referred to as an "air conditioner") is a liquefied refrigerant obtained by compressing a refrigerant sealed in a circulation system constituting an air conditioning cycle with a compressor and then liquefying it with a condenser. Is pumped to the evaporator, and the cooling function is realized by generating cold air whose temperature is lowered by the heat absorption by the vaporization of the refrigerant in the evaporator. As the refrigerant, Freon-free R134a, HFO-1234yf and the like are used. In the case of a vehicle equipped with an engine such as a gasoline engine or a diesel engine, a part of the shaft output of the engine is used to drive the compressor.

When an engine is used as a drive source for a compressor, the air conditioner cannot generally be operated when the engine is stopped. For this reason, if a commercial vehicle such as a bus, truck, or trailer is parked for a long time for a break in a parking area on a highway or waiting for unloading at a cargo delivery destination, the engine will be stopped for air conditioning. Since the device cannot be operated, there is a problem that it becomes difficult to keep the environment inside the vehicle comfortable. Moreover, since an electric vehicle is not originally equipped with an engine, the compressor cannot be operated by the engine output.

Therefore, an air conditioner of a type in which a motor for driving a compressor is operated by the electric power of a battery mounted on a vehicle has been developed and put into practical use. When a battery is used as a drive source, it is required to reduce the amount of electric power used as much as possible, unlike the case where the engine output is used. In the case of electric vehicles, the power consumption related to air conditioning directly affects the cruising range of the vehicle, and even in the case of batteries of vehicles equipped with an engine, if the voltage drops due to the power consumption related to air conditioning, it will be difficult to start the engine. Because there is a problem.

From this point of view, for example, Patent Document 1 aims to provide an air conditioner for a vehicle capable of preventing a decrease in the travelable distance of the vehicle and continuing air conditioning in the vehicle interior, for the purpose of providing an environment. A normal mode for switching between heating operation, dehumidifying and heating operation, cooling operation, and dehumidifying and cooling operation based on conditions, and heating operation, dehumidifying and heating operation, cooling operation, and dehumidifying and cooling operation are switched based on environmental conditions, and cloudiness determination means. It is possible to switch between the first energy-saving mode, which performs dehumidifying and heating operation only when it is determined that the window glass becomes cloudy, and the second energy-saving mode, which switches between heating operation, cooling operation, and dehumidifying and cooling operation based on environmental conditions. Air conditioners for vehicles have been proposed.

Japanese Unexamined Patent Publication No. 2012-176659

In Patent Document 1, heating, cooling, and dehumidifying / cooling / heating operations are switched according to the fogging of the window glass and environmental conditions, but in an inappropriate state such as the windows and doors of the passenger compartment being opened during the cooling operation. When the air conditioner is operating, the power consumption continues to be excessive, such as the compressor being continuously operated in the high rotation range in order to bring the temperature inside the vehicle closer to the target temperature, and the battery is excessively consumed. There was a problem that there was a risk that it would end up.

The present invention has been made to solve the above-mentioned problems, and when it is detected that the temperature in the vehicle interior does not drop as expected, an upper limit is set or the operation of the number of revolutions of the compressor or the like is set. One object of the present invention is to provide a vehicle air conditioner and a control method for a vehicle air conditioner capable of preventing the battery from being consumed by stopping the vehicle.

In order to solve the above and other problems, one embodiment of the present invention comprises a compressor driven by power from a battery for compressing the refrigerant and a compressor compressed by the compressor. A condenser for liquefying, an evaporator for vaporizing the liquefied refrigerant to absorb heat and lowering the temperature of the air supplied to the vehicle interior, and a power source for driving the compressor using DC power from the battery. An air conditioner for a vehicle provided with a power conversion unit for converting to the compressor, according to a difference between a target set temperature in the vehicle interior of the vehicle and a measured air temperature in the vehicle interior. In order to control the power supply of the compressor, the compressor is operated at a rotation speed corresponding to the difference between the target set temperature and the measured air temperature. When it is determined that the compressor has been operated for the first time or longer at a rotation speed exceeding the first rotation speed, the supply is such that the rotation speed of the compressor is equal to or less than the second rotation speed lower than the first rotation speed. It has a power control unit that controls power.

If the power control unit determines that the difference between the target set temperature and the measured air temperature exceeds a predetermined value even after a second time has elapsed after the start of operation of the compressor, the compression is performed. It can be configured to stop the power supply to the machine.

In addition, another aspect of the present invention includes a compressor driven by electric power from a battery for compressing the refrigerant, a condenser for liquefying the refrigerant compressed by the compressor, and the liquefaction. An evaporator for vaporizing the refrigerant to absorb heat and lowering the temperature of the air supplied to the passenger compartment, and an evaporator fan motor driven by electric power from the battery for driving the fan that blows air to the evaporator. An air conditioner for a vehicle provided with a power conversion unit for converting DC power from the battery into power for driving the compressor and driving the evaporator fan motor, the interior of the vehicle. Rotation according to the difference between the target set temperature and the measured air temperature in order to control the power supply to the evaporator fan motor according to the difference between the target set temperature and the measured air temperature in the vehicle interior. When it is determined that the evaporator fan motor is operated according to the number, and the evaporator fan motor is operated for the first time or more at a rotation speed exceeding the first rotation speed after the start of operation. In addition, it has a power control unit that controls the supply power so that the rotation speed of the evaporator fan motor is equal to or lower than the second rotation speed lower than the first rotation speed.

According to the above-described aspect of the present invention, when it is detected that the temperature inside the vehicle interior does not drop as expected, an upper limit is set on the rotation speed of the compressor or the like, or the operation is stopped to prevent battery consumption. be able to.

FIG. 1 is a schematic view showing a vehicle to which a vehicle air conditioner according to an embodiment of the present invention is attached. FIG. 2 is a schematic view showing an overall configuration example of an air conditioner for a vehicle. FIG. 3 is an electric system diagram of an air conditioner for a vehicle. FIG. 4 is a schematic diagram showing a configuration example of a compressor motor drive control circuit and an evaporator fan motor drive control circuit. FIG. 5 is a diagram showing an example of control data 435 of the present embodiment. FIG. 6 is a diagram showing an example of an evaporator fan motor control flow. FIG. 7 is a diagram showing an example of a compressor motor drive control flow. FIG. 8 is a schematic view showing changes over time in the measured air temperature and the compressor rotation speed in an inappropriate operating environment such as when the passenger compartment is open.

Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings. The present invention is not limited to those embodiments.

First, FIG. 1 shows a partial schematic view of a vehicle to which an air conditioner for a vehicle according to an embodiment of the present invention is attached. FIG. 1 shows a left side view of a freight vehicle 100 such as a truck. In order to clearly show the mounting state of the vehicle air conditioner of the present embodiment, FIG. 1 schematically shows a peripheral portion of the driver's cab 110 of the freight vehicle 100. The freight vehicle 100 has a driver's cab 110 and a luggage compartment 140, which are mounted on the chassis 130.

The vehicle air conditioner 1 of the present embodiment supplies electric power to the indoor unit 10 for supplying cold air to the inside of the vehicle, the outdoor unit 20 for exchanging heat between the inside air and the outside air, and the indoor unit 10 and the outdoor unit 20. It has a DC / AC inverter 30 (hereinafter abbreviated as "inverter 30") which is a power conversion unit for supplying power. A battery 40, which is a power source for the freight vehicle 100, is installed on the side surface of the chassis 130. Further, in the driver's cab 110, an inverter 30 for converting DC power from the battery 40 into AC power is installed.

A baffle plate 120 for reducing the air resistance by the driver's cab 110 during traveling is provided on the outer upper surface of the driver's cab 110. Generally, the baffle plate 120 is a member that forms a convex surface that rises smoothly from the front side of the cab 110, and a member for attaching to the upper surface of the cab 110 and a reinforcing member for the baffle plate 120 itself are provided on the back side thereof. A certain space is formed. In the present embodiment, the outdoor unit 20 of the air conditioner is installed in the inner space formed by the baffle plate 120. The outdoor unit 20 may be installed not only on the roof of the driver's cab 110 but also between the outside and the luggage compartment 140 of the driver's cab 110.

In the living space 112 provided in the driver's cab 110 in preparation for long-distance operation of the freight vehicle 100, an indoor unit 10 is provided together with, for example, a nap bed 115. The indoor unit 10 and the outdoor unit 20 are connected by a pipeline (not shown), and form a flow path for a refrigerant for heat exchange between the indoor unit 10 and the outdoor unit 20.

The freight vehicle 100 shown in FIG. 1 is an example, and may be a vehicle such as a trailer in which the driver's cab 110 and the luggage compartment 140 can be separated. Further, the installation location of the inverter 30 and the battery 40 can be appropriately selected according to the configuration of the vehicle to be installed.

Next, an example of the overall configuration of the air conditioner 1 of the present embodiment will be described. FIG. 2 schematically shows an overall configuration example of the air conditioner 1. The air conditioner 1 includes a compressor 21, a condenser 25, and an evaporator 11. In the present embodiment, the evaporator 11 is provided in the indoor unit 10, and the compressor 21 and the condenser 25 are provided in the outdoor unit 20. Each of the compressor 21, the condenser 25, and the evaporator 11 is connected in a liquidtight state by a pipe 50 so that the refrigerant can circulate. The pipe 50 can be appropriately configured by a material having pressure resistance and corrosion resistance (for example, copper or the like) according to the type of the refrigerant and the working pressure.

In the air conditioner 1 illustrated in FIG. 2, the refrigerant compressed by the compressor 21 is cooled by the condenser 25, liquefied, and pumped toward the indoor unit 10. The high-temperature and high-pressure liquid refrigerant becomes a low-temperature and low-pressure mist through a minute flow path such as a capillary tube and is ejected into the evaporator 11 to vaporize, and the heat of vaporization at that time absorbs heat from the air around the evaporator 11. The air cooled in this way is discharged from the indoor unit 10 into the living space 112 of the driver's cab 110 to exert an air conditioning effect. As will be described later, the indoor unit 10 is provided with a fan for sending the air cooled around the evaporator 11 into the living space 112. The above air-conditioning cycle is the same as that of a normal vehicle air-conditioning device, but in the present embodiment, the fans in the compressor 21 and the indoor unit 10 are electric.

Next, the configuration of the electric system of the air conditioner 1 of the present embodiment will be described. FIG. 3 shows an example of a control system of the air conditioner 1 of the present embodiment. The power source of the air conditioner 1 is composed of a battery 40 and an inverter 30 that converts the DC power of the battery 40 into AC power. With this configuration, the air conditioner 1 can be operated to supply cold air into the driver's cab 110 even when the engine of the vehicle is stopped. As the battery 40, a general lead storage battery can be used as an automobile battery, but the battery 40 is not particularly limited to a specific type of battery. When a lead-acid battery is used, it is practically preferable to use a lead-acid battery having a 5-hour rate capacity specified in JIS D 5301 and having a capacity of 120 Ah or more.

The inverter 30 is a power conversion unit for supplying electric power to the compressor driving motor 22 (hereinafter, also referred to as “CP motor 22”). In the present embodiment, the power from the battery 40 is supplied as the power source for the EV fan motor 12 and the CD fan motor 26, and the single-phase AC220V is supplied as the power source for the CP motor 22. However, other power specifications are used. There is no problem. As the circuit method of the inverter 30, an appropriate method such as a pulse width modulation (PWM) method can be adopted. Further, the output capacity of the inverter 30 may be determined according to the specifications of each motor or the like as a load. In addition, EV, CD, and CP are abbreviations indicating an evaporator (Evaporator), a condenser (Condenser), and a compressor (Compressor), respectively.

The indoor unit 10 includes an EV fan motor 12, an EV fan motor drive circuit 13, an EV fan motor drive control circuit 14 (hereinafter, also referred to as “EV fan control circuit 14”), and an input / output interface unit 17. .. The EV fan motor 12 is a motor that drives a blower fan for blowing air to the evaporator 11, and for example, a brushless DC motor or the like is used. The EV fan motor drive circuit 13 is a circuit block that receives power from the battery 40 to generate an output voltage for driving the EV fan motor 12, and is, for example, an IGBT gate drive circuit that controls the power supplied to the EV fan motor 12. Can be configured as. As the circuit method of this circuit block, a PWM method or the like can be used.

The output of the EV fan motor drive circuit 13 is controlled by the EV fan control circuit 14. The EV fan control circuit 14 includes a processor such as a CPU as described later, acquires air temperature information sent from the indoor unit 10 from the temperature sensor 16, and motors from the rotation sensor 12A provided in the EV fan motor 12. Information on the number of rotations of 12 is acquired, and the output of the EV fan motor drive circuit 13 is controlled by arithmetic processing executed by the processor based on the information. A power switch 15 is provided between the inverter 30 and the inputs of the EV fan motor drive circuit 13 and the EV fan control circuit 14. By turning off the power switch 15 when the air conditioner 10 is not operated. , The circuits 13 and 14 are configured so that unnecessary power is not consumed.

The rotation sensor 12A is a sensor for detecting the rotor rotation speed of the EV fan motor 12, and is configured by using, for example, a magnetoresistive element and a Hall element. The temperature sensor 16 is realized by using an element such as a thermistor. The temperature sensor 16 is installed on the outer upper surface of the indoor unit 10, for example, and measures the air temperature of the living space 112 in which the indoor unit 10 is installed. The output signal of the temperature sensor 16 is also transmitted to the compressor motor drive control circuit 24 (hereinafter, also referred to as “CP control circuit 24”) of the outdoor unit 20 through the communication line 70 connecting the indoor unit 10 and the outdoor unit 20. Be supplied. As a result, the temperature data in the living space 112 can be used on the outdoor unit 20 side as well.

The input / output interface unit 17 is a block that realizes data input such as setting a target temperature in the living space 112 by the air conditioner 1, and data output functions such as current room temperature and abnormality detection notification by the indoor unit 10 or the outdoor unit 20. For example, it is composed of input / output devices such as a liquid crystal display panel, a touch panel, and a push switch. The input / output interface unit 17 is communicably connected to the EV fan control circuit 14 to exchange data. Further, the input / output interface unit 17 can exchange data with the CP control circuit 24 of the outdoor unit 20 through the communication line 70 connecting the indoor unit 10 and the outdoor unit 20.
The above configuration of the indoor unit 10 is an example, and various other configurations can be adopted in order to realize the function of the air conditioner 1 of the present embodiment described later.

Next, an example of the electrical configuration of the outdoor unit 20 will be described. The outdoor unit 20 is provided with a blower fan for blowing air from the condenser 25 in order to promote heat dissipation from the condenser 25, and is driven by the CD fan motor 26. As the CD fan motor 26, for example, a single-phase AC motor, a brushless DC motor, or the like can be used. The CD fan motor 26 is driven by the CD fan motor drive circuit 27. Single-phase AC100V is supplied from the inverter 30 to the CD fan motor drive circuit 27, and is converted into a drive current for driving the CD fan motor 26 by the CD fan motor drive circuit 27. Since the CD fan motor 26 only needs to be operated at a constant rotation speed during the operation of the air conditioner 1, the CD fan motor drive circuit 27 may be designed according to the specifications of the CD fan motor 26 so as to realize the function. ..

The outdoor unit 20 is also provided with a compressor driving motor 22 (hereinafter, also referred to as “CP motor 22”) for driving the compressor 21, and in the present embodiment, an AC three-phase induction motor is adopted. The CP motor 22 is driven by three-phase AC power supplied from the compressor drive motor drive circuit 23 (hereinafter, also referred to as “CP drive circuit 23”). The CP motor drive circuit 23 can be configured by, for example, a PWM method using an IGBT as a switching element, but another appropriate method may be adopted depending on the type and specifications of the CP motor 22.

The output of the CP drive circuit 23 is controlled by the CP control circuit 24. In the present embodiment, the CP control circuit 24 is a gate drive circuit that controls the on / off control of the IGBT of the CP drive circuit 23. As will be described later, the CP control circuit 24 includes a processor such as a CPU, temperature data acquired from the temperature sensor 16 in the indoor unit 10, and the rotation speed of the motor 22 acquired from the rotation sensor 22A provided in the CP motor 22. Based on the data, the output of the CP drive circuit 23 is controlled by arithmetic processing executed by the processor.

The rotation sensor 22A is a sensor for detecting the rotor rotation speed of the CP motor 22, and is configured by using, for example, a magnetoresistive element or a Hall element, like the rotation sensor 12A. As described above, the output signal of the temperature sensor 16 installed on the indoor unit 10 side is also input to the CP control circuit 24 through the communication line 70 connecting the indoor unit 10 and the outdoor unit 20.

Next, a configuration example of the EV fan control circuit 14 and the CP control circuit 24 will be described. FIG. 4 is a schematic diagram illustrating the functional blocks of the EV fan control circuit 14 and the CP control circuit 24 in relation to the hardware configuration. Hereinafter, the EV fan control circuit 14 and the CP control circuit 24 are collectively referred to as a motor control circuit 400 (power control unit). The motor control circuit 400 includes a processor 410, an input / output unit 420, and a memory 430. The processor 410 is an arithmetic unit such as a CPU and an MPU, and realizes the motor control of the present embodiment described later. The input / output unit 420 has a function of executing data input / output processing with an external device, and as hardware, various setting data such as a target room temperature from the input / output interface unit 17 of the indoor unit 10 and a temperature sensor. Output for outputting drive output signals (gate signals) to input data buffer circuit, EV fan drive circuit 13, CP drive circuit 23, such as temperature measurement data from 16 and rotation speed data from rotation sensors 12A and 22A. Includes buffer circuit.

The memory 430 provides a program for controlling the air conditioner 1 of the present embodiment and a storage area for storing data and the like used by the program, and is composed of, for example, a storage device such as a ROM or a RAM. .. In the example of FIG. 4, the temperature data processing unit 431, the load rotation speed processing unit 432, the command output calculation unit 433, the data input / output unit 434, and the control data 435 are stored in the memory 430. The temperature data processing unit 431, the load rotation speed processing unit 432, the command output calculation unit 433, and the data input / output unit 434 are programs executed by the processor 410. The control data 435 is data used by the above program.

The temperature data processing unit 431 has a function of receiving various setting data such as a target room temperature from the input / output interface unit 17 of the indoor unit 10 and temperature measurement data from the temperature sensor 16 and delivering them to the command output calculation unit 433. The load rotation speed processing unit 432 has a function of receiving rotation speed data from the rotation speed sensors 12A and 22A and delivering the rotation speed data to the command output calculation unit 433. The command output calculation unit 433 has a function of generating an output signal to the EV fan drive circuit 13 and the CP drive circuit 23 by using each received temperature data, rotation speed data, and control data described later. The data processing executed by the command output calculation unit 433 will be described later with reference to a processing flow example.

The data input / output unit 434 has a function of data input / output processing between the processor 410 and the memory 430. The control data 435 includes control pattern data showing the relationship between the difference between the input target set temperature and the measured room temperature and the rotation speeds of the EV fan motor 12 and the CP motor 22, and the upper limit of the rotation speeds described later. The setting data related to, the setting data related to the difference between the target set temperature and the measured temperature, and the setting data related to the duration of the state where the difference between the target set temperature and the measured temperature exceeds a predetermined value are stored.

FIG. 5 shows an example of control data 435. The control data 435 of the present embodiment includes drive output signal pattern data 4351, rotation speed limit time determination threshold 4352 (first time), CP operation stop time determination threshold 4353 (second time), and high rotation speed determination threshold 4354. (First rotation speed), temperature difference determination threshold value 4355, rotation speed upper limit value 4356 (second rotation speed), rotation speed and temperature history information 4357. The drive output signal pattern data 4351 is used to achieve the difference between the target temperature and the measured temperature of the EV fan motor 12 and the CP motor 22, the target rotation speed to be set for the difference, and the target rotation speed. , The relationship between the drive output signals to be output to the EV fan motor drive circuit 13 and the CP motor drive circuit 23 is held as a control pattern. The rotation speed limit time determination threshold value 4352 is time data that serves as a determination threshold value for whether or not to set an upper limit on the rotation speed of the EV fan motor 12 and the CP motor 22, and stores a numerical value such as 10 minutes. The CP operation stop time determination threshold value 4353 is time data that serves as a determination threshold value for whether or not to stop the operation of the CP motor, and stores a numerical value such as 30 minutes. The high rotation speed determination threshold value 4354 is numerical data set for determining whether or not the rotation speeds of the EV fan motor 12 and the CP motor 22 are in the high rotation speed region. The temperature difference determination threshold value 4355 is a difference threshold value between the target temperature and the measurement temperature used for determining whether to stop the operation of the CP motor 22. The rotation speed upper limit value 4356 is a rotation speed upper limit value set for the rotation speed of the EV fan motor 12 and the CP motor 22, and is held for each of the EV fan motor 12 and the CP motor 22. The rotation speed and temperature history information 4357 stores changes in the rotation speed and temperature measurement values over time for each of the EV fan motor 12 and the CP motor 22, and is used as history data for determining the rotation speed limit and CP operation stop. Will be done. Note that FIG. 5 shows an example of the configuration, which can be designed according to the configuration and specifications of the air conditioner 1 to which the present invention is applied. For example, the rotation speeds of the EV fan motor 12 of the indoor unit 10 and the CP motor 24 of the outdoor unit 20 are set through the input / output interface unit 17 so that the user can set the strength of the cooling capacity according to his / her preference. You may be able to do it. Further, in order to appropriately change the cooling capacity for each season and each month, the rotation speeds of the EV fan motor 12 of the indoor unit 10 and the CP motor 24 of the outdoor unit 20 are based on the time data held by the motor control circuit 400. May be able to be set. Further, in order to prevent excessive battery consumption due to continuous operation such as during summer night parking, an off-timer function is provided in the input / output interface unit 17 of the indoor unit 10, and the indoor unit 10 and the outdoor unit 10 and the outdoor unit are provided after a predetermined time has elapsed from the start of operation. It can also be configured so that the operation of 20 is stopped.

Next, the drive control of the EV fan motor 12 and the CP motor 22 in the air conditioner 1 having the above configuration will be described. First, the drive control of the EV fan motor 12 will be described. FIG. 6 shows an example of a drive control processing flow of the EV fan motor 12 executed by the EV fan control circuit 14 included in the indoor unit 10 of the air conditioner 1 of the present embodiment.

As a basic operation, the EV fan control circuit 14 has a target rotation speed determined according to the difference between the target temperature set through the input / output interface unit 17 of the indoor unit 10 and the measured temperature measured by the temperature sensor 16. , A drive output signal to the EV fan drive circuit 13 is generated based on the difference from the measured rotation speed input from the rotation sensor 12A. As described above with respect to FIG. 5, pattern data showing the relationship between the difference between the target temperature and the measured temperature and the target rotation speed, and pattern data showing the relationship between the difference between the target rotation speed and the measured rotation speed and the drive output signal. Is stored in advance as control data 435 in the memory 430. On the premise of this basic operation, the EV fan control circuit 14 controls to set an upper limit on the rotation speed of the EV fan motor 12 when the high rotation speed operation of the EV fan motor 12 continues for a predetermined time.

Referring to FIG. 6, first, when the EV fan control circuit 14 starts control when the power of the air conditioner 1 is turned on (S600), the EV fan control circuit 14 is set by the temperature data processing unit 431 through the input / output interface unit 17 of the indoor unit 10. The target temperature data is acquired and stored in the work area of the memory 430 (S610). Next, the temperature data processing unit 431 acquires the measured temperature data from the temperature sensor 16 and stores it in the work area of the memory 430 (S620). Next, the rotation speed processing unit 432 acquires the measurement rotation speed data of the EV fan motor 12 from the rotation sensor 12A and stores it in the work area of the memory 430 (S630). Based on the above acquired data, the command output calculation unit 433 calculates the target rotation speed to be given to the EV fan drive circuit 13 with reference to the drive output signal pattern data stored as the control data 435 (S540). ..

Here, the command output calculation unit 433 reads the high rotation speed operation determination threshold value Rs and the high rotation speed operation duration threshold value ts1 from the control data 435, and reads the history of the measured rotation speed data stored in the work area of the memory 430. With reference to this, it is determined whether or not the state in which the rotation speed r of the EV motor 12 satisfies r> Rs continues beyond the threshold value t1 (S650). When it is determined that the duration of the above state is ts1 or less (S650, No), the command output calculation unit 433 calculates a drive output signal based on the target rotation speed calculated in S640, and causes the EV fan drive circuit 13 to calculate the drive output signal. Output (S670) and return to the processing of S610.

On the other hand, when it is determined that the state in which the rotation speed r of the EV fan motor 12 satisfies r> Rs continues beyond the threshold value ts1 (S650, Yes), the command output calculation unit 433 rotates the EV fan motor 12. The upper limit value Rmax, which is set in advance as the control data 435, is set in the number (S660). Then, the command output calculation unit 433 in S670 calculates the drive output signal based on the target rotation speed which is the upper limit value set in S660, outputs it to the EV fan drive circuit 13 (S670), and returns to the processing of S610. ..

By such a drive control process of the EV fan motor 12, for example, the air conditioner 1 is operated with the windows and doors of the cab 110 in which the indoor unit 10 is installed open, and the temperature in the living space 112 is raised. If the EV fan motor 12 does not easily drop to the target set temperature and the EV fan motor 12 continues to operate at high speed for a long time, an upper limit is set for the rotation speed of the EV fan motor 12 and the high speed operation continues unnecessarily. This prevents the power of the battery 40 from being wasted.

Next, the drive control of the CP motor 22 will be described. FIG. 7 shows an example of a drive control processing flow of the CP motor 22 executed by the CP motor control circuit 24 included in the outdoor unit 20 of the air conditioner 1 of the present embodiment.

Similar to the EV fan control circuit 14, the CP motor control circuit 24, as a basic operation, determines the difference between the target temperature set through the input / output interface unit 17 of the indoor unit 10 and the measured temperature measured by the temperature sensor 16. A drive output signal to the CP motor drive circuit 23 is generated based on the difference between the target rotation speed determined accordingly and the measured rotation speed input from the rotation sensor 12A. Similar to the EV fan motor drive control circuit 14, the CP motor control circuit 24 is a control that suppresses power consumption by setting an upper limit on the rotation speed when a high rotation operation exceeding a predetermined threshold value is continued for a predetermined time. I do. In addition, if the operation exceeding a certain number of revolutions is continued for a longer period of time, it is determined that the state is abnormal and the operation of the CP motor 22 is stopped to prevent unnecessary power consumption of the battery 40.

Referring to FIG. 7, when the CP motor control circuit 24 starts control when the power of the air conditioner 1 is turned on (S700), the target temperature data, the measured temperature data, and the measured rotation are the same as in the case of the EV fan motor control. The number data is acquired, and the target rotation speed to be given to the CP motor drive circuit 23 is calculated with reference to the drive output signal pattern data stored as the control data 435 (S710 to S740).

Here, the command output calculation unit 433 reads the high rotation speed operation determination threshold Rs and the high rotation speed operation duration threshold ts1 from the control data 435 and stores them in the work area of the memory 430, similarly to the control of the EV fan motor 12. With reference to the history of the measured rotation speed data, it is determined whether the state in which the rotation speed r of the EV motor 12 satisfies r> Rs continues beyond the threshold value t1 (S750). When it is determined that the duration of the above state is ts1 or less (S750, No), the command output calculation unit 433 calculates a drive output signal based on the target rotation speed calculated in S740, and causes the CP motor drive circuit 23 to calculate the drive output signal. Output (S795) and return to the processing of S710.

On the other hand, when it is determined that the state in which the rotation speed r of the CP motor 22 satisfies r> Rs continues beyond the threshold value ts1 (S750, Yes), the command output calculation unit 433 further determines the value of the temperature measurement data. It is determined whether the state in which the difference ΔT between the target set temperature and the target set temperature exceeds the predetermined threshold value Ts continues to exceed the predetermined time threshold value ts2 (S760). When it is determined that the state of ΔT> Ts continues beyond ts2 (S760, Yes), the command output calculation unit 433 commands the CP motor drive circuit 23 to stop the operation, and the input / output interface of the indoor unit 10 An abnormality detection is output to the unit 17 through the communication line 70, and the process ends (S770 to S780). In this way, if the abnormal state in which the temperature around the indoor unit 10 does not sufficiently decrease with respect to the target set temperature continues even after the lapse of a predetermined time, the operation of the CP motor 22 is stopped to cause the abnormal state. It is possible to prevent the battery 40 from being wasted. In particular, since the CP motor 22 consumes more power than the EV fan motor 12, the effect of preventing the consumption of the battery 40 by stopping its operation is great.

When it is determined in S760 that the condition for stopping the operation of the CP motor 22 is not satisfied (S760, No), the command output calculation unit 433 is set in advance as control data 435 in the rotation speed of the CP motor 22. The upper limit value Rmax is set (S790). Then, in S795, the command output calculation unit 433 calculates a drive output signal based on the target rotation speed which is the upper limit value set in S790, outputs the drive output signal to the CP motor drive circuit 13 (S795), and returns to the processing of S710. ..

By such a drive control process of the CP motor 22, for example, the air conditioner 1 is operated with the windows and doors of the cab 110 in which the indoor unit 10 is installed open, and the temperature in the living space 112 is the target. If the CP motor 22 does not easily drop to the set temperature and the high-speed operation of the CP motor 22 continues for a long time, an upper limit is set for the rotation speed of the CP motor 22, and the high-speed operation is unnecessarily continued and the battery It prevents 40 electric powers from being wasted.

FIG. 8 shows an example of time changes in temperature and rotation speed when the CP motor drive control described above is executed. It is assumed that when the temperature in the living space 112 in which the indoor unit 10 is installed is T0, the operation of the air conditioner 1 is started with the target set temperature as TT. The CP motor 22 starts operation at a rotation speed R0, but since the temperature does not easily drop because, for example, the windows and doors of the driver's cab 110 are open, the rotation speed R0 is higher than the rotation speed determination threshold Rs. Continue driving. When the high rotation operation continuation time exceeds the time determination threshold value ts1, the upper limit value Rmax is set for the rotation speed of the CP motor 22, and the CP motor 22 continues the operation at the rotation speed Rmax.

It is assumed that the temperature in the living space 112 does not decrease sufficiently, and the state in which the difference ΔT between the target temperature TT and the measured temperature is larger than the temperature determination threshold value Ts continues to exceed the time determination threshold value ts2. In this case, the operation of the CP motor 22 is stopped by the CP motor control circuit 24. In this way, if the abnormal state in which the temperature in the living space 112 where the indoor unit 10 is installed does not drop sufficiently continues for some reason, the operation of the CP motor 22 at high rotation speed is suppressed, and further, under certain conditions. Under the control, the operation is stopped, so that unnecessary consumption of the battery 40 can be prevented.

The rotation speed determination threshold value Rs, the rotation speed upper limit value Rmax, and the time determination threshold values ts1 and ts2 used for the above motor control are appropriately set in consideration of conditions such as the power consumption of the CP motor 22 and the capacity of the battery 40. be able to. Further, in the above embodiment, the EV fan motor 12 and the CP motor 22 are controlled to suppress continuous operation in a high rotation region in a predetermined time, and the state in which the difference between the target temperature and the measured temperature exceeds the predetermined value is constant. The control for stopping the operation when the operation is continued for more than a time is performed for the CP motor 22, but the above control is performed only for the CP motor 22 which accounts for a larger proportion of the power consumption of the air conditioner 1. It may be. In that case, the operation of the EV fan motor 12 may be stopped when the operation of the CP motor 22 is stopped.

As described in detail above, according to the vehicle air conditioner of the present embodiment, when it is detected that the temperature inside the vehicle does not drop as expected, the upper limit of the rotation speed of the fan of the compressor or the indoor unit is set. It is possible to prevent the battery from being consumed by providing or stopping the operation of the compressor, and it is possible to prevent inconveniences in the electrical system such as deterioration of engine startability.

1 Vehicle air conditioner 10 Indoor unit 11 Evaporator 12 EV fan motor 12A, 22A Rotation sensor 13 EV fan motor drive circuit 14 EV fan motor drive control circuit 15 Power switch 16 Temperature sensor 18 Expansion valve 20 Outdoor unit 21 Compressor 22 Compressor motor 23 CP motor drive circuit 24 CP motor drive control circuit 25 Condenser 30 DC / AC inverter 40 Battery 400 Motor control circuit 410 Processor 420 Input / output unit 430 Memory 431 Temperature data processing unit 432 Load rotation speed processing unit 433 Command output Calculation unit 434 Data input / output unit 435 Control data

Claims (4)

A compressor driven by the power from the battery to compress the refrigerant,
A condenser for liquefying the refrigerant compressed by the compressor, and
An evaporator for vaporizing the liquefied refrigerant to absorb heat and lowering the temperature of the air supplied to the passenger compartment.
A vehicle air conditioner including a power conversion unit for converting DC power from the battery into power for driving the compressor.
In order to control the power supply to the compressor according to the difference between the target set temperature in the vehicle interior and the measured air temperature in the vehicle interior, the difference between the target set temperature and the measured air temperature is used. When it is determined that the compressor is operated at a corresponding rotation speed and the compressor is operated at a rotation speed exceeding the first rotation speed for the first time or more after the start of operation. It has a power control unit that controls the supply power so that the rotation speed of the compressor is equal to or lower than the second rotation speed lower than the first rotation speed.
Vehicle air conditioner. The vehicle air conditioner according to claim 1.
If the power control unit determines that the difference between the target set temperature and the measured air temperature exceeds a predetermined value even after a second time has elapsed after the start of operation of the compressor, the compression is performed. Stop the power supply to the machine,
Vehicle air conditioner. A compressor driven by the power from the battery to compress the refrigerant,
A condenser for liquefying the refrigerant compressed by the compressor, and
An evaporator for vaporizing the liquefied refrigerant to absorb heat and lowering the temperature of the air supplied to the passenger compartment.
An evaporator fan motor driven by electric power from a battery for driving a fan that blows air to the evaporator, and
An air conditioner for vehicles including a power conversion unit for converting DC power from the battery into power for driving the compressor and driving the evaporator fan motor.
In order to control the power supply to the evaporator fan motor according to the difference between the target set temperature in the vehicle interior of the vehicle and the measured air temperature in the vehicle interior, the target set temperature and the measured air temperature are set. The evaporator fan motor is configured to operate at a rotation speed according to the difference, and after the start of operation, the evaporator fan motor is operated at a rotation speed exceeding the first rotation speed for the first time or more. It has a power control unit that controls the supplied power so that the rotation speed of the evaporator fan motor becomes equal to or lower than the second rotation speed lower than the first rotation speed when it is determined to be present.
Vehicle air conditioner. A compressor driven by the power from the battery to compress the refrigerant,
A condenser for liquefying the refrigerant compressed by the compressor, and
An evaporator for vaporizing the liquefied refrigerant to absorb heat and lowering the temperature of the air supplied to the passenger compartment.
A control method for a vehicle air conditioner including a power conversion unit for converting DC power from the battery into power for driving the compressor.
In order to control the power supply to the compressor according to the difference between the target set temperature in the vehicle interior and the measured air temperature in the vehicle interior, the difference between the target set temperature and the measured air temperature is used. When it is determined that the compressor is operated at a corresponding rotation speed and the compressor is operated at a rotation speed exceeding the first rotation speed for the first time or more after the start of operation. , The power supply is controlled so that the rotation speed of the compressor is equal to or lower than the second rotation speed, which is lower than the first rotation speed.
How to control a vehicle air conditioner.

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