JP2012052683A - Air conditioning control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioning control device that can suppress or avoid the occurrence of liquid compression.SOLUTION: The air conditioning control device includes: a temperature detector A for detecting the temperature in an air-conditioned room, a temperature detector B for detecting the temperature of an electric compressor in a refrigerating circuit, and a temperature detector C for detecting an external air; and a control unit 1 for determining the start rotation speed for the electric compressor based on the difference in temperatures by the temperature detector A, the temperature detector B or the temperature detector C when an air conditioner starts. This arrangement can allow the electric compressor to be driven at an appropriate rotation speed even if the electric compressor has a liquid refrigerant therein, and also can prevent the generation of liquid compression depending on the liquid state, thus enabling smooth air conditioning.

Description

The present invention relates to control of an electric compressor of an air conditioner, and more particularly to an air conditioner control device of a vehicle air conditioner.

  Conventionally, a compressor provided in this type of refrigeration circuit sucks, compresses and discharges gas refrigerant in normal operation, but after being left for a long time or when the compressor is stopped at a low temperature, Depending on the relationship between the compressor temperature and the like, the refrigerant may accumulate in the compressor in a liquid refrigerant state instead of a gas state. It has been well known that if the air conditioner is started in a state where the liquid refrigerant is accumulated, the compressor is started as it is to cause liquid compression.

  When liquid compression occurs, the compression load becomes very large, the sliding part in the compression part wears down and the durability decreases, and the sound at the time of liquid compression becomes loud and may cause discomfort to the passenger .

  Under such circumstances, based on the means for outputting the start signal at the start of the air conditioner and the output signal, the motor winding is heated without rotating the motor rotor of the electric compressor, thereby heating the liquid refrigerant. Electric compressors that avoid liquid compression by evaporating are known. (For example, refer to Patent Document 1).

JP 2007-162572 A

  However, in the conventional configuration, although the liquid refrigerant does not always accumulate in the compressor at the time of starting the air conditioner, the electric compressor is stopped for a certain period of time. It stopped, and the air-conditioned room was not quickly air-conditioned, and there was a problem that comfort deteriorated.

  In order to solve the above problems, an air conditioning control device according to the present invention detects temperature detection means A for detecting the temperature in the air conditioning room, temperature detection means B for detecting the temperature of the electric compressor in the refrigeration circuit, and external air. And a control unit for determining a starting rotational speed of the electric compressor based on a temperature difference between the temperature detection unit A and the temperature detection unit B or the temperature detection unit C when the air conditioner is started. It is set as the structure provided with.

  As a result, even if there is a liquid refrigerant in the electric compressor, the electric compressor can be driven at an appropriate number of revolutions, and air conditioning can be performed quickly while preventing the occurrence of liquid compression depending on the refrigerant state. .

  In the present invention, when liquid refrigerant is accumulated in the electric compressor at the time of starting, the operation is started at a low speed to reduce the compression load of liquid compression, improving the reliability of the electric compressor and uncomfortable at the time of liquid compression. The electric compressor can be operated with a small compression noise. Further, when liquid refrigerant is not accumulated in the electric compressor at the time of start-up, the air-conditioner can be quickly air-conditioned because the engine is started at the target rotational speed designated by the air-conditioning control unit.

Schematic air conditioning system diagram when the air conditioning control device in Embodiment 1 of the present invention is applied Sectional drawing of the electric compressor in Embodiment 1 of this invention The flowchart which shows control of the control part in Embodiment 21 of this invention. Schematic air conditioning system diagram when the air conditioning control device in Embodiment 2 of the present invention is applied Sectional drawing of the electric compressor in Embodiment 3 of this invention Schematic air conditioning system diagram when the air conditioning control device in Embodiment 4 of the present invention is applied Schematic block diagram of an electric compressor and an air conditioning control device in Embodiment 5 of the present invention

  An air conditioning control device according to a first aspect of the present invention includes a temperature detecting means A for detecting the temperature in the air-conditioned room, a temperature detecting means B for detecting the electric compressor temperature of the refrigeration circuit, and a temperature detecting means C for detecting outside air. And having a control unit that determines the starting rotational speed of the electric compressor based on the temperature difference between the temperature detecting means A and the temperature detecting means B or the temperature detecting means C when the air conditioner is started. .

  Accordingly, the electric compressor can be driven at an appropriate rotation speed according to the state of the refrigerant in the electric compressor, and air conditioning can be performed quickly while preventing the occurrence of liquid compression according to the refrigerant state. .

  When the temperature detection means B is higher than the temperature detection means A or the temperature detection means C, the air conditioning control device according to the second invention starts the electric compressor at the target rotational speed Nt instructed by the air conditioning control section, and detects the temperature. When the means B is lower than the temperature detection means A or the temperature detection means C, the rotational speed of the electric compressor is controlled so as to start at a starting rotational speed Ns lower than the target rotational speed Nt instructed by the air conditioning control unit. .

  Thereby, when the temperature detection means B is higher than the temperature detection means A or the temperature detection means C, since the liquid refrigerant is not accumulated in the electric compressor, by starting at the target rotational speed Nt instructed from the air conditioning control unit, Air conditioning can be performed quickly while preventing the occurrence of liquid compression. Further, when the temperature detecting means B is lower than the temperature detecting means A or C, since a large amount of liquid refrigerant is accumulated in the electric compressor, the starting rotational speed lower than the target rotational speed Nt instructed from the air conditioning control unit. Since it starts with several Ns, the liquid compression load can be reduced.

  In the air conditioning control device according to the third aspect of the invention, the temperature detecting means A for detecting the temperature in the air-conditioned room is used as the ambient temperature detecting means for the evaporator of the refrigeration circuit, and is also used as an antifreeze sensor provided in the evaporator of the air conditioning apparatus. It is as composition to do.

  As a result, since the refrigeration circuit is normally equipped with a freeze prevention sensor, it is not necessary to attach the temperature detection means A separately, and the cost increase can be suppressed.

  In an air conditioning control device according to a fourth aspect of the present invention, the electric compressor has a compression unit, a motor unit that drives the compression unit, and an inverter that drives the motor unit, and the inverter is a refrigerant from a refrigeration circuit that is sucked into the compression unit. The inverter is provided at a position to be cooled, and the inverter includes a temperature sensor that detects the temperature of the inverter, and the inverter temperature sensor that detects the temperature of the inverter also serves as the temperature detection means B.

  As a result, the inverter temperature sensor detects the temperature in the vicinity of the liquid refrigerant accumulated in the electric compressor, so that it is closer to the temperature of the liquid refrigerant and liquid compression can be reliably prevented. Moreover, it is not necessary to attach a sensor for detecting the temperature inside the electric compressor, and the cost increase can be suppressed.

  In the air conditioning control device according to the fifth aspect of the invention, the temperature detecting means C for detecting the outside air temperature is used as the ambient temperature detecting means for the condenser of the refrigeration circuit, and the outside air temperature sensor provided near the condenser of the air conditioning apparatus is also used. As a configuration.

  As a result, the refrigeration circuit is normally equipped with an outside air sensor, so that it is not necessary to attach the temperature detecting means A separately, and an increase in cost can be suppressed.

  An air conditioning control device according to a sixth aspect of the present invention has an air conditioning control unit that controls the air conditioning device, and the start signal of the air conditioning control unit and the temperature signals of the temperature detecting means A and the temperature detecting means C are communicated by the air conditioning control unit. An electric compressor that can be input to an inverter via a line and can calculate and instruct the rotation speed at the time of start-up by the inverter alone is mounted.

  As a result, the electric compressor itself has a control function for preventing liquid compression independently from the air conditioning control unit. Therefore, even when installed in various other air conditioners, the electric compressor can be reliably prevented. Can protect.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
1st Embodiment of the air-conditioning control apparatus of this invention is described using FIGS. The air conditioning control device is applied to a refrigeration circuit for a vehicle (automobile). As shown in FIG. 1, the air conditioning control device includes a control unit 1 provided in an air conditioning control unit 10, a temperature detection means A in the electric compressor 100 and the air conditioning chamber, and a temperature detection means B ( 2) and temperature detecting means C for detecting outside air.

  The high-temperature and high-pressure gas refrigerant compressed by the electric compressor 100 is condensed by the condenser 2 through the pipe to become liquid refrigerant, and the refrigerant that has been depressurized by the expansion valve 3 to become low-temperature and low-pressure is inside the air conditioning chamber by the evaporator 4. Heat exchanges with air evaporates and returns to the electric compressor 100. Comfortable air conditioning can be obtained by cooling the indoor air with the evaporator 4. A radiator 5 and a blower 6 for cooling a drive source such as an engine (not shown) or an electric motor (not shown) are provided downstream of the condenser 2, and heat is also exchanged by blowing air to the condenser 2.

  As shown in FIG. 2, the electric compressor 100 is formed as a sealed container by a comp case 101, a rear cover 102, and an inverter case 103. The motor part X and the compression part Y are accommodated in the comp case 101, and the inverter 104 is accommodated in the inverter case 103.

  The motor unit X is an AC three-phase motor, and includes a rotor 105 and a stator 106. A rotating shaft 107 of the rotor 105 is connected to a movable scroll 110 constituting the compression unit Y via a slide bush 108 and a bearing 109. The motor unit X is driven by receiving electric power (current) output from the inverter 104.

The compression unit Y operates by driving the motor unit X, sucks low-temperature and low-pressure gas refrigerant in the refrigeration circuit from the suction port 111 opened in the comp case 101, passes through the suction passage 112, and the fixed scroll 113 and the movable scroll 110. The gas refrigerant is compressed into a high-temperature and high-pressure gas refrigerant in a compression chamber 114 constituted by: The high-temperature high-pressure gas refrigerant is discharged by pushing up the discharge valve 115, flows into the high-pressure space in the comp case 101 through the high-pressure passage 116, and is discharged from the discharge port 117 provided in the rear cover 102 into the refrigeration circuit.

  The inverter 104 is a well-known DC-AC converter, converts a DC current from a battery (not shown) into an AC current, and changes the output current to the motor unit X by ON / OFF of a switching element provided therein. To do. The input side of the switching element is connected to the battery and the air conditioning control unit 10, and the output side is connected to the motor unit X. The inverter case 103 is fixed so as to face the suction passage 112 through which refrigerant is sucked, and the inverter 104 attached to the inverter case 103 is cooled by the refrigerant passing through the suction passage 112. .

Normally, the air conditioner control device receives an air conditioner start signal, an environmental condition signal for cooling, etc., and based on these signals, determines the target rotational speed Nt of the electric compressor and adjusts the output current of the inverter 104. The number of rotations of the motor unit X is controlled.
The control unit 1 in the air conditioning control unit 10 determines the starting rotational speed of the electric compressor based on the temperature difference between the temperature detection unit B and the temperature detection unit A or the temperature detection unit C when the air conditioner is started. It is a thing. This will be described below with reference to FIG.

  When the vehicle is parked under hot weather in the summer, the interior of the vehicle becomes hot due to sunlight, while the electric compressor is installed in the engine room of the vehicle, so it is in the shade, so the temperature is lower than the interior of the vehicle or outside. It has been left for a long time. The refrigerant is condensed in the electric compressor having a low temperature to become a liquid refrigerant and is in a full liquid state. Further, since the passenger compartment temperature is high, the target rotational speed Nt of the electric compressor is increased in order to cool the passenger compartment quickly.

  As described above, when the temperature detection means B is lower than the temperature detection means A or the temperature detection means C, the liquid refrigerant is accumulated in the electric compressor, so that the control unit 1 performs the target rotation commanded from the air conditioning control unit 10. The electric compressor is started at a starting rotational speed Ns lower than the number Nt.

  Thereby, the load of liquid compression can be reduced, and generation | occurrence | production of the unpleasant sound by liquid compression can be suppressed.

  In addition, when starting the electric compressor during traveling in winter, the ambient temperature of the electric compressor 100 in the engine room is higher than the outside air temperature due to the heat radiation of the radiator 5, and the outside air temperature is lower than that in the passenger compartment. Liquid refrigerant accumulates in the condenser. In such a case, since the temperature detection means B becomes higher than the temperature detection means A or the temperature detection means C, the control unit 1 starts the electric compressor at the target rotational speed Nt instructed from the air conditioning control unit 10.

  As described above, when the temperature detection unit B is higher than the temperature detection unit A or the temperature detection unit C, no liquid refrigerant is accumulated in the electric compressor, so the engine is started at the target rotational speed Nt instructed from the air conditioning control unit 10. Thus, it is possible to quickly air-condition while preventing the occurrence of liquid compression.

(Embodiment 2)
Next, FIG. 4 is a schematic air conditioning system diagram when the air conditioning control device of the second embodiment of the present invention is applied.

  As shown in FIG. 4, the air-conditioning control device uses temperature detection means A for detecting the temperature in the air-conditioned room as ambient temperature detection means for the evaporator 4 of the refrigeration circuit, and is also used as the antifreeze sensor 7 provided in the evaporator 4. It is a thing.

  As a result, the freezing prevention sensor 7 is usually attached to the refrigeration circuit, so that it is not necessary to attach the temperature detecting means A separately, and the cost increase can be suppressed.

(Embodiment 3)
Next, FIG. 5 is a cross-sectional view of an electric compressor according to a third embodiment of the present invention.

  As shown in FIG. 5, the electric compressor 100 in this embodiment is provided with a temperature sensor 8 that detects the temperature of the inverter 104 in the inverter 104, and the temperature detection means B uses the inverter temperature that detects the temperature of the inverter 104. The sensor 8 is also used as a configuration.

  Thus, since the inverter temperature sensor 8 detects the temperature in the vicinity of the liquid refrigerant accumulated in the electric compressor 100, the temperature of the liquid refrigerant is more accurately detected, and liquid compression can be reliably prevented. it can. In addition, there is no need to attach a temperature sensor for detecting the temperature inside the electric compressor, and the cost is not increased.

(Embodiment 4)
Next, FIG. 6 is a schematic air conditioning system diagram when the air conditioning control device of the fourth embodiment of the present invention is applied.

  The air-conditioning control apparatus of the present invention uses the temperature detection means C for detecting the outside air temperature as the ambient temperature detection means for the condenser of the refrigeration circuit, and is also used as the outside air temperature sensor 9 provided near the condenser 2 of the air-conditioning apparatus. It is as.

  As a result, the refrigeration circuit is normally equipped with the outside air sensor 9, so that it is not necessary to attach the temperature detecting means A separately, and the cost is not increased.

(Embodiment 5)
Next, FIG. 7 is a schematic configuration diagram of an electric compressor and an air conditioning control device according to a fifth embodiment of the present invention.

  The air conditioning control unit 10 and the electric compressor 100 are a power line 9 a that supplies electric power (current) from the air conditioning control unit 10, and a communication line 9 b that communicates a rotation speed signal and a temperature signal between the air conditioning control unit 10 and the electric compressor 100. And the control unit 1 is incorporated in the inverter 104 of the electric compressor 100. That is, the start signal of the air conditioning control device from the air conditioning control unit 10 and the temperature signal of the temperature detection means A are input to the inverter 104 including the control unit 1 via the communication line 9a from the air conditioning control unit 10, and the inverter 104 alone This is an inverter circuit that can calculate and indicate the number of rotations of the electric compressor 100 at the time of starting.

  As a result, the electric compressor 100 itself can be provided with a control function for preventing liquid compression independently from the air conditioning control device, and reliably prevents liquid compression even when mounted on various other air conditioning devices. The reliability of the electric compressor 100 can be improved.

  In addition, in each said Embodiment 1-5, although the control part 1 demonstrated the case where it integrated in the air-conditioning control part 10, the control part 1 and the air-conditioning control part 10 may be comprised separately. It ’s good.

  The air-conditioning control apparatus of the present invention can quickly air-condition while preventing the occurrence of liquid compression according to the refrigerant state, and is particularly suitable for a vehicle air-conditioning apparatus.

DESCRIPTION OF SYMBOLS 1 Control part A Temperature detection means in an air-conditioning room B Temperature detection means of an electric compressor C Outside air temperature detection means 7 Freezing prevention sensor 8 Temperature sensor 9 Outside air temperature sensor 9a Power line 9b Communication line communication line 10 Air conditioning control part 100 Electric compressor X Motor part Y Compression part

Claims (6)

The temperature detecting means A for detecting the temperature in the air-conditioned room, the temperature detecting means B for detecting the electric compressor temperature of the refrigeration circuit, and the temperature detecting means C for detecting the outside air, the temperature when the air conditioner is activated. An air-conditioning control apparatus comprising a control unit that determines a starting rotational speed of the electric compressor based on a temperature difference between the detection means A and the temperature detection means B or the temperature detection means C. When the temperature detection means B is higher than the temperature detection means A or the temperature detection means C, the control section starts the electric compressor at the target rotational speed Nt instructed by the air conditioning control section, and the temperature detection means B is the temperature detection means. The air conditioning control according to claim 1, wherein when the temperature is lower than A or the temperature detecting means C, the rotational speed of the electric compressor is controlled so as to start at a starting rotational speed Ns lower than the target rotational speed Nt instructed by the air conditioning control unit. apparatus. 3. The temperature detecting means A for detecting the temperature in the air-conditioning room is used as an ambient temperature detecting means for the evaporator of the refrigeration circuit, and is also used as an anti-freezing sensor provided in the evaporator of the air-conditioning apparatus. The air conditioning control device described in 1. The electric compressor has a compression unit, a motor unit that drives the compressor, and an inverter that drives the motor unit, and the inverter is provided at a position cooled by the refrigerant from the refrigeration circuit that is sucked into the compression unit. The inverter includes a temperature sensor that detects the temperature of the inverter, and the inverter temperature sensor that detects the temperature of the inverter also serves as the temperature detection means B. 5. Air conditioning control device. The temperature detection means C for detecting the temperature of the outside air is used as an ambient temperature detection means for the condenser, and is also used as an outside air sensor equipped in the air conditioner. Air conditioning control device. An air-conditioning control unit for controlling the air-conditioning apparatus, and the start signal of the air-conditioning control unit and the temperature signals of the temperature detection means A and the temperature detection means C are input to the inverter via the communication line of the air-conditioning control unit; The air-conditioning control apparatus according to any one of claims 1 to 5, which is equipped with an electric compressor capable of calculating and instructing the rotational speed at the time of starting alone.