JPH076652B2 - Heat pump system and operating method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a heat pump system for cooling a control device such as an inverter control unit and an operating method thereof.

(Prior Art) As a conventional technology relating to this type of heat pump system, there is JP-B 62-19535. In this conventional example, as shown in FIG. 5, the outdoor heat exchanger 1 of the outdoor unit Y, the capillary tube 2, the indoor heat exchanger 3 of the indoor unit X, the four-way switching valve 4 and the compressor 5 in the air conditioner are arranged. The refrigerant pipes 6 are sequentially connected. The low-pressure pipe 10 in the refrigerant pipe 6 is arranged so that heat can be transferred to the power transistor 12 of the inverter control unit via the heat dissipation plate 11, and the power transistor 12 is cooled by the low-temperature refrigerant flowing in the low-pressure pipe 10. It is designed to do.
Incidentally, 13 is a blower fan.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional example, there is a problem that the low temperature low-pressure tube 10 is likely to condense at high humidity such as summer and the power transistor 12 is likely to cause insulation failure due to dew condensation water.
Further, there is also a problem that vibration of the low-pressure pipe 10 close to the compressor 5 is transmitted to the power transistor 12 and impairs reliability of the power transistor 12 and the like.

The present invention has been made to solve the above-mentioned conventional drawbacks, and an object thereof is to prevent the occurrence of insulation failure or deterioration of reliability of the heating element while cooling the heating element. (EN) Provided is a heat pump system and an operating method thereof.

(Means for Solving the Problem) Therefore, in the heat pump system according to the first aspect, the compressor 5, the outdoor unit exchanger 1, the pressure reducing mechanism 2, and the indoor heat exchanger 3 are connected by the refrigerant pipe 6 to circulate the refrigerant. A heat pump system comprising a control device 20 having a heating element 12 and forming a path, wherein a refrigerant pipe 6 between the outdoor heat exchanger 1 and the pressure reducing mechanism 2 can exchange heat with the heating element 12. It is arranged.

Further, in the heat pump system according to the second aspect, the control device 20 includes an electric component 21, and the control device is further provided.
A blower fan 13 that can blow air to the controller 20, a temperature sensor 22 that measures the temperature inside the control device 20, and a temperature signal 23 from the temperature sensor 22 correspond to the life reduction temperature T of the electrical component 21. A fan control unit 24 is provided to control the operation of the blower fan 13 so as to maintain the internal temperature below the reference temperature TG.

Further, in a third aspect, the method for operating the heat pump system according to the first aspect, wherein in the heating operation cycle, the heat is generated in the refrigerant pipe 6 in a portion which is arranged to exchange heat with the heating element 12. The heat radiation from the element 12 is recovered.

(Operation) In the first aspect, the refrigerant flows while performing heat exchange between the indoor heat exchanger 3 and the outdoor heat exchanger 1 during operation of the heat pump system, and has a temperature not extremely lower than the dew point temperature. The heat generating element 12 is cooled by the refrigerant pipe 6 between the outdoor heat exchanger 1 and the pressure reducing mechanism 2 through which heat flows. For this reason, there is no possibility that condensed water will come into contact with the heating element 12. Further, since the refrigerant pipe 6 between the outdoor heat exchanger 1 and the pressure reducing mechanism 2 is separated from the compressor 1 which is a vibration source, the heating element 12 is also prevented from vibrating.

In the second aspect, the temperature sensor 22 measures the temperature inside the refrigerator, and the temperature signal 23 from the temperature sensor 22 is input to the fan control unit 24, and the fan control unit 24 keeps the temperature inside the refrigerator below the reference temperature TG. The blower fan 13 is driven so as to maintain the temperature. Therefore, the electric component 21 is cooled to the reference temperature TG or lower by the blown air from the blower fan 13.

Further, in the third aspect, the heat generated by the heat generating element 12 heats the refrigerant pipe 6 between the outdoor heat exchanger 1 and the pressure reducing mechanism 2, and the refrigerant flowing inside the refrigerant pipe 6 generates heat by the heat generating element 12. Is collected and the heating capacity is improved by the amount of heat generated by the heating element 12 during the heating operation of the heat pump system.

(Example) First, a specific example of the heat pump system of the present invention will be described in detail with reference to the drawings. The first
In the drawings below, the portions designated by the same reference numerals as in the conventional example of FIG. 5 are the same or corresponding portions.

In FIG. 2 showing an outdoor unit Y of an air conditioner adopting the heat pump system of the present invention, the outdoor unit Y is provided with an outdoor heat exchanger 1, a compressor 5, an inverter control unit 20 (control device) and the like. There is. The inverter control unit 20 accommodates an inverter including a power transistor 12 which is a heating element and an electric component 21 such as a capacitor, and the air blown by the outdoor fan 13 is introduced into the inverter control unit 20. Has been done. The heat resistant temperature S of the power transistor 12 is, for example,
On the other hand, the service life lowering temperature T at which the service life of the electrical component 21 is reduced is about 105 ° C., for example.

Further, the power transistor 12 contacts the cooling unit 30 of the refrigerant pipe 6 which will be described in detail later via the heat sink 11, and the cooling unit 30
And the power transistor 12 are arranged so that they can exchange heat. The thermistor 22 is installed in the inverter control unit 20.
(Temperature sensor) is arranged, and the thermistor 22 measures the temperature inside the inverter control unit 20. In FIG. 1 showing the piping system of the heat pump system, the cooling unit 30 of the cooling pipe 6 corresponds to the refrigerant pipe 6 between the outdoor heat exchanger 1 and the capillary tube 2 (pressure reducing mechanism). Is designed to cool the power transistor 12 via the heat sink 11.

In FIG. 2, the thermistor 22 measures the internal temperature TD of the inverter control unit 20 in which the electric component 21 is housed, and the temperature signal 23 thereof is a fan control unit 24 for controlling the operation of the outdoor fan 13. Has been entered in. The fan control unit 24 is provided with an arithmetic circuit 25, a drive circuit 26, and the like. Based on the temperature signal 23, the arithmetic circuit 25 sets the reference temperature TG corresponding to the service life lowering temperature T as the internal temperature of the refrigerator. When it exceeds, the drive signal from the drive circuit 26 to the outdoor fan 13
It is designed to output.

The above-described cooling control of the electric component 21 will be described with reference to the flowchart of FIG. 3. When the outdoor fan 13 is stopped, the thermistor 22 measures the internal temperature TD in step S1, and the temperature signal
23 is output. Next, in step S2, the reference temperature TG is compared with the internal temperature TD. If the internal temperature TD is higher than the reference temperature TG (YES), the process proceeds to step S3 to cool the electrical component 21. When it is determined that it is necessary, the outdoor fan 13 is driven, and air is blown into the inverter control unit 20 to supply electrical components.
Cool 21. Then, the process returns from step S3 to step S1 and the above control is repeated. On the other hand, the internal temperature TD is the reference temperature.
When the temperature is the same as or lower than that of TG, the stopped state of the outdoor fan 13 is continued.

Next, the operation state of the above-mentioned one embodiment apparatus will be described. During both cooling and heating, the refrigerant at a temperature not extremely lower than the dew point temperature flows through the cooling section 30 of the refrigeration cycle shown in FIG. 1, and heat is radiated without dew condensation in the cooling section 30. The power transistor 12 is cooled via the plate 11. Therefore, as shown in FIG. 4, when there is no cooling action by the cooling unit 30, the temperature of the power transistor 12 has a characteristic 31a.
The above heat-resistant temperature S of the power transistor 12 becomes
Will be exceeded. However, when the power transistor 12 is cooled by the cooling unit 30 as described above, it is prevented from being cooled like the characteristic 31 and exceeding the heat resistant temperature S.

On the other hand, the inside temperature TD corresponding to the temperature of the electric component 21 is maintained below the reference temperature TG, which is slightly lower than T, which is the life decreasing temperature of the electric component 21, by the cooling control by the fan controller 24. That is, the temperature characteristics when the above cooling control is performed
32 continues to rise in the range where the outdoor fan 13 is stopped, and when the outdoor fan 13 is ON-OFF controlled by the characteristic 32
Is also raised and lowered, and the outdoor fan 13 is driven to maintain the temperature below the reference temperature TG. If the cooling control by the outdoor fan 13 as described above is not performed, the temperature of the electrical component 21 is the characteristic 32a.
As described above, the reference temperature TG and the life reduction temperature T are exceeded.

Next, in the operating method for heating the heat pump system in FIG. 1, as is well known, the refrigerant circulates in the refrigerant pipe 6 in the counterclockwise direction in the figure, and after being condensed in the indoor heat exchanger 3, the outdoor heat exchanger 1
However, before flowing into the outdoor heat exchanger 1, the cooling unit 30 receives heat from the power transistor 12 on the contrary, and the cooling unit 30 heats the refrigerant. Therefore, the waste heat of the power transistor 12 is recovered by the cooling unit 30 as a refrigerant and is reused by the indoor heat exchanger 3 as the amount of heat during heating.

The specific embodiments of the present invention have been described above,
The present invention is not limited to the above-mentioned embodiments, but can be implemented with various modifications within the scope of the present invention. For example, in the above embodiment, the capillary tube 2 is used as the pressure reducing mechanism, but other mechanism such as a pressure reducing valve may be used.

(Effect of the invention) As described above, in the heat pump system according to the first aspect, the heating element is provided in the refrigerant pipe between the outdoor heat exchanger and the decompression mechanism in which the refrigerant whose temperature is not extremely lower than the dew point temperature flows. It can be cooled, so that there is no risk of dew water coming into contact with the heating element. Further, since the refrigerant pipe between the outdoor heat exchanger and the pressure reducing mechanism is separated from the compressor that is the vibration source, the heating element is also prevented from vibrating.

Further, in the second aspect, the blower fan can be driven so as to maintain the internal cold storage temperature below the reference temperature, and the blown air from the blower fan cools the electrical components to below the reference temperature. .

Further, in the third aspect, in the heating operation cycle, the heat generated by the heating element is recovered by the refrigerant flowing inside the refrigerant pipe between the outdoor heat exchanger and the pressure reducing mechanism. It is possible to improve the heating capacity by the amount of heat generation.

[Brief description of drawings]

FIG. 1 is a piping system diagram showing a heat pump system according to an embodiment of the present invention, FIG. 2 is a schematic structural view of an outdoor unit, and FIG.
FIG. 4 is a flow chart showing the cooling control process, FIG. 4 is a graph showing changes in temperature with time, and FIG. 5 is a structural schematic diagram showing a conventional example. 1 ... Outdoor heat exchanger, 2 ... Capillary tube, 3 ...
… Indoor heat exchanger, 5 …… compressor, 6 …… refrigerant piping, 20 ・ ・ ・
… Inverter control unit (control device), 21 …… Electrical components, 22 …… Thermistor (temperature sensor), 24 …… Fan drive section.

Claims (3)

[Claims] 1. A refrigerant circulation path is formed by connecting a compressor (5), an outdoor heat exchanger (1), a pressure reducing mechanism (2) and an indoor heat exchanger (3) with a refrigerant pipe (6), Heating element (12)
A heat pump system including a control device (20) having: a refrigerant pipe (6) between the outdoor heat exchanger (1) and a decompression mechanism (2), capable of exchanging heat with the heating element (12). A heat pump system characterized by being placed in. 2. The control device (20) includes an electric component (21), and further, a blower fan (13) capable of blowing air to the control device (20), and a temperature inside the refrigerator of the control device (20) are measured. Based on the temperature sensor (22) and the temperature signal (23) from the temperature sensor (22), the temperature inside the storage chamber is reduced to the reference temperature (TG) or less corresponding to the life decreasing temperature (T) of the electrical component (21). The heat pump system according to claim 1, further comprising a fan control section (24) for controlling the operation of the blower fan (13) so as to maintain the temperature. 3. A method of operating the heat pump system according to claim 1, wherein in the heating operation cycle, the refrigerant pipe (6) is arranged in a portion of the refrigerant pipe (6) arranged to exchange heat with the heating element (12). A method for operating a heat pump system, comprising collecting the heat radiation from the heating element (12).