Control device and heat exchange system

Abstract

To provide a control device and a heat exchange system capable of easily maintaining a temperature of an electric component at a constant level or more.SOLUTION: A control device is a device for controlling a heat exchange system including air blowing means for taking in and discharging air that exchanges heat with a refrigerant. The control device includes: one or more electric components that control the heat exchange system; an electric product box in which the one or more electric components are accommodated and air flows inside, outside or both of them by air blowing means; heat radiation means that protrudes from an outer surface of the electric product box and radiates heat emitted by at least one of the one or more electric components; and heating means for heating at least one of the one or more electric components directly or via the heat radiation means. The control device controls heating by the heating means on the basis of presence / absence of an operation of the heat exchange system and a temperature of inside of the electric product box or an ambient temperature of the heat exchange system.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a control device for controlling a heat exchange system and a heat exchange system. [Background technology]

[0002] A heat exchange system such as an air conditioner includes a compressor, an expansion valve, a fan, etc., and is equipped with a control device that controls these devices. The control device houses electrical components such as a control board in an electrical equipment box, and is located inside the casing of the outdoor unit of the heat exchange system.

[0003] Electrical components operate and generate heat while the heat exchange system is running. If heat continues to accumulate in the electrical components, the temperature will exceed the upper limit of their operating temperature. Furthermore, as the outdoor temperature drops, the temperature inside the electrical equipment box of the outdoor unit also drops, and the temperature may fall below the lower limit of their operating temperature. When electrical components exceed their upper or lower limit of operating temperature, the operation of the electrical components cannot be guaranteed, resulting in a problem of reduced reliability.

[0004] Therefore, air conditioning devices are known that have a heater inside an electrical equipment box and a heat sink on the outer surface of the electrical equipment box that dissipates heat generated by the electrical components using multiple fins, thereby suppressing temperature increases (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-270732 [Patent Document 2] International Publication No. 2017 / 077649 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the above-mentioned conventional technology, when the outside temperature is low, even if the electrical components generate heat during operation, the temperature inside the electrical equipment box during operation is lower than during standby, and the degree of temperature rise varies greatly depending on whether the unit is in operation or not, making it difficult to maintain the temperature of the electrical components at a constant level or higher. [Means for solving the problem]

[0007] In view of the above-mentioned problems, the present invention provides a control device for controlling a heat exchange system including a blower that takes in and discharges air that exchanges heat with a refrigerant, the control device comprising: one or more electrical components for controlling the heat exchange system; an electrical equipment box that houses one or more electrical components therein and in which air is circulated between the inside and / or the outside by a blower; a heat dissipation means that protrudes to the outside of the electrical equipment box and dissipates heat generated by at least one of the one or more electrical components; a heating means for heating at least one of the one or more electrical components directly or via a heat dissipation means; Including, A control device is provided that controls heating by the heating means based on whether the heat exchange system is operating and the temperature inside the electrical equipment box or the ambient temperature around the heat exchange system. [Effects of the Invention]

[0008] According to the present invention, it becomes easy to maintain the temperature of the electrical components at a constant level or higher. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram showing an example of the configuration of an air conditioning apparatus as an example of a heat exchange system. [Figure 2] FIG. 2 is a diagram showing an example of the arrangement of components in an outdoor unit of an air conditioning apparatus. [Figure 3] FIG. 3 is a diagram illustrating the flow of air inside the outdoor unit of the air conditioner during operation. [Figure 4] FIG. 2 is a diagram showing an example of the arrangement of electrical components in an electrical equipment box arranged in the outdoor unit. [Figure 5]FIG. 4 is a diagram illustrating the flow of air inside the electrical equipment box while the air conditioner is operating. [Figure 6] 1A to 1C are diagrams illustrating the structure, mounting position, and mounting method of a heat sink. [Figure 7] A diagram showing an example of applying thermal grease between an electrical component and a heat sink. [Figure 8] 3A to 3C are diagrams illustrating a first example of the shape of a heater, and the position and method of attaching the heater to a heat sink. [Figure 9] 10A and 10B are diagrams illustrating a second example of the shape of the heater and the mounting position and mounting method of the heater on the heat sink. [Figure 10] 10A and 10B are diagrams illustrating a third example of the shape of a heater and the position and method of attaching the heater to a heat sink. [Figure 11] 4 is a flowchart showing an example of heating control of a heater. DETAILED DESCRIPTION OF THE INVENTION

[0010] FIG. 1 is a diagram showing an example of the configuration of an air conditioner as an example of a heat exchange system. In a heat exchange system, a refrigerant serving as a heat medium is compressed and expanded while circulating within a sealed system, and a fluid such as air or water, which is the object of heat exchange, is indirectly brought into contact with the refrigerant, thereby exchanging heat between the refrigerant and the fluid. The heat exchange system also exchanges heat between the refrigerant and air, such as outside air, before or after exchanging heat with the fluid. Therefore, the heat exchange system is not limited to an air conditioner as long as it has such a configuration, but may also be a refrigerator, chiller, heat pump, or the like. Hereinafter, the heat exchange system will be described as an air conditioner.

[0011] The air conditioning device 10 includes an indoor unit 11 installed in the space (indoors) to be air-conditioned, and an outdoor unit 20 installed outdoors, and performs air conditioning by circulating a refrigerant between the indoor unit 11 and the outdoor unit 20 and exchanging heat with the air in the room.

[0012] The indoor unit 11 and the outdoor unit 20 may each be configured with two or more units, and two or more indoor units 11 may be connected to one outdoor unit 20. Hydrofluorocarbons (HFCs) and hydrofluoroolefins (HFOs) can be used as refrigerants. Examples of HFCs include R410A and R32. Examples of HFOs include R1234yf.

[0013] The indoor unit 11 communicates wirelessly with the remote control using infrared or other means to receive various signals such as operation commands, stop commands, commands to change the set temperature, and commands to change the operation mode. The indoor unit 11 and the remote control may be connected by a communication line and configured to perform wired communication. The indoor unit 11 is connected to the outdoor unit 20 via a communication line and works in cooperation with the outdoor unit 20 to condition the air in the room.

[0014] The indoor unit 11 starts up upon receiving an operation command from the remote control, and instructs the outdoor unit 20 to start up. After starting up, the outdoor unit 20 adjusts the compressor rotation speed and the opening of the expansion valve, etc., and controls the amount of refrigerant circulating, etc., so that the indoor temperature becomes the set temperature.

[0015] The indoor unit 11 includes an indoor heat exchanger 12, an indoor fan 13, and an indoor fan motor 14. The indoor fan 13 is driven by the indoor fan motor 14 to take in indoor air and send it to the indoor heat exchanger 12. The indoor heat exchanger 12 has heat transfer tubes through which a refrigerant flows, and is configured so that the sent air comes into contact with the surface of the heat transfer tubes to exchange heat. The air that has undergone heat exchange by the indoor heat exchanger 12 is discharged into the room.

[0016] The indoor unit 11 may also be equipped with various sensors for measuring the indoor temperature, etc., an indoor expansion valve, etc. The indoor unit 11 is equipped with an indoor control device, which controls the rotation speed of the indoor fan motor 14, the opening degree of the indoor expansion valve, etc.

[0017] The outdoor unit 20 includes a compressor 21, an accumulator 22, a four-way valve 23, an expansion valve (outdoor expansion valve) 24, an outdoor heat exchanger 25, an outdoor fan 26 as a blower, and an outdoor fan motor 27. The compressor 21 is, for example, a rotary compressor or a scroll compressor, and is driven by a compressor motor to compress low-pressure gas refrigerant and discharge it as high-pressure gas refrigerant. The accumulator 22 is a container for storing liquid return during transient periods and adjusts the refrigerant to an appropriate quality. The quality fraction is the proportion of steam in wet steam, which indicates the mixed state of steam and micro-droplets.

[0018] The four-way valve 23 is a valve that switches the refrigerant flow path depending on the operating state (operating mode) of the air conditioner 10. The operating modes include cooling mode, heating mode, and fan mode. The expansion valve 24 is a valve that reduces the pressure of the high-pressure refrigerant and expands it. The outdoor fan 26 is driven by an outdoor fan motor 27, takes in outdoor air, and sends it to the outdoor heat exchanger 25. Like the indoor heat exchanger 12, the outdoor heat exchanger 25 has heat transfer tubes through which the refrigerant flows, and is configured so that the sent-in air comes into contact with the surface of the heat transfer tubes to exchange heat. The air that has undergone heat exchange by the outdoor heat exchanger 25 is discharged outdoors.

[0019] The outdoor unit 20 further includes a control device (outdoor control device) 28. The control device 28 is connected to the compressor 21, the four-way valve 23, the expansion valve 24, and the outdoor fan motor 27, and controls these. Specifically, it controls the rotation speed of the compressor motor, the opening of the expansion valve 24, the rotation speed of the outdoor fan motor 27, etc. In order to control these, various sensors, such as a sensor that detects the outdoor air temperature, are also attached to the outdoor unit 20. The control device 28 controls these based on information detected by the various sensors.

[0020] During heating operation, the indoor heat exchanger 12 is used as a condenser, and the outdoor heat exchanger 25 is used as an evaporator. Therefore, the control device 28 circulates the refrigerant sealed in the system in the following order, as shown by the arrows: compressor 21, four-way valve 23, indoor heat exchanger 12, expansion valve 24, outdoor heat exchanger 25, four-way valve 23, accumulator 22, and compressor 21.

[0021] The compressor 21 compresses a low-temperature, low-pressure gaseous refrigerant (refrigerant gas) and discharges it as a high-temperature, high-pressure refrigerant gas. The indoor heat exchanger 12 exchanges heat with indoor air to cool and condense the refrigerant gas. The expansion valve 24 reduces the pressure of the liquid refrigerant. The opening of the expansion valve 24 is adjusted by a control device 28 so that the amount of liquid is appropriate. The outdoor heat exchanger 25 exchanges heat with outdoor air to evaporate the refrigerant. The refrigerant is then sent to the accumulator 22 through a four-way valve 23 and returned to the compressor 21.

[0022] FIG. 2 is a diagram showing an example of the arrangement of components within the outdoor unit 20 of the air conditioner 10. The outdoor unit 20 has an outdoor fan 26 at the top of a substantially rectangular parallelepiped casing 30. Inside the casing 30, there is a machine chamber 31 accommodating the compressor 21 and other components, an accumulator 22, and an electrical equipment box 32. The casing 30 has a bottom plate, a metal plate to which the electrical equipment box 32 is attached, an upper opening communicating with the outdoor fan 26, and a side opening for drawing air. The casing 30 may have, for example, a frame member to which a mesh member is attached, with the opening of the mesh member serving as the side opening, and the outdoor heat exchanger 25 disposed inside the frame member adjacent to the mesh member. Alternatively, the outdoor heat exchanger 25 may be used as part of the casing 30, and be disposed so as to cover part of the side. When the outdoor heat exchanger 25 is used as part of the casing 30, the gaps between the heat transfer tubes of the outdoor heat exchanger 25 formed in a panel shape using heat transfer tubes can be used as the side openings.

[0023] The machine room 31 and the accumulator 22 are heavy objects and are therefore installed at the bottom of the casing 30. The electrical equipment box 32 is installed above the machine room 31 in consideration of manual operation, making it easier to operate.

[0024] 3 is a diagram illustrating the flow of air inside the outdoor unit 20 while the air conditioner 10 is in operation. When the outdoor heat exchanger 25 is disposed inside the casing 30 of the outdoor unit 20, the interior of the casing 30 is divided into two spaces (a first space 33 and a second space 34) by the outdoor heat exchanger 25. Because the outdoor heat exchanger 25 is disposed adjacent to a side opening of the casing 30, the second space 34 is smaller than the first space 33.

[0025] The outdoor unit 20 uses the outdoor fan 26 to take in outside air from a side opening in the casing 30 into the second space 34 inside the casing 30. If one side surface formed by sheet metal of the casing 30 is defined as the front, side openings can be provided on the other three surfaces: the left and right side surfaces and the back surface, and air can be taken in through side openings provided on these three surfaces. Note that the side openings are not limited to being provided on the three surfaces: the left and right side surfaces and the back surface, and they may also be provided on a part of the front surface, and air can also be taken in through side openings provided in a part of the front surface.

[0026] The air taken into the second space 34 inside the casing 30 passes through the gaps between the heat transfer tubes of the outdoor heat exchanger 25 while in contact with the heat transfer tubes, thereby exchanging heat with the refrigerant circulating inside the heat transfer tubes. The air that has exchanged heat in the outdoor heat exchanger 25 enters the first space 33 and is discharged to the outside from the top of the casing 30 (a hole in the ceiling panel). Note that if the outdoor heat exchanger 25 forms part of the side of the casing 30, there is no second space 34, and the air is drawn directly into the first space 33 through the gaps between the heat transfer tubes.

[0027] In the outdoor unit 20, the outdoor heat exchanger 25 functions as a condenser during cooling operation, so the air taken into the second space 34 is heated by the outdoor heat exchanger 25 and is discharged to the outside from the first space 33 at a higher temperature than when it was taken in.

[0028] On the other hand, in the outdoor unit 20, the outdoor heat exchanger 25 acts as an evaporator during heating operation, so the air taken into the second space 34 is cooled by the outdoor heat exchanger 25 and discharged to the outside from the first space 33 at a lower temperature than when it was taken in.

[0029] 4 is a diagram showing an example of the arrangement of electrical components in an electrical equipment box 32 arranged in the outdoor unit 20. A control board 40 serving as control means for controlling the operation of the air conditioner 10 is housed inside the electrical equipment box 32. The control board 40 includes a processor and memory, and controls the starting and stopping of the motor of the compressor 21, the starting and stopping of the outdoor fan motor 27, the valve opening degree of the expansion valve 24, etc.

[0030] An inverter power module assembly 41 is housed in the electrical equipment box 32 as a load adjusting means for adjusting the rotation speed and workload of the motor of the compressor 21 to match a target load. The inverter power module assembly 41 includes multiple semiconductor switching elements, and adjusts the rotation speed and other parameters by changing the timing of switching the semiconductor switching elements on and off. The semiconductor switching elements are, for example, field effect transistors such as MOSFETs (Metal Oxide Semiconductor Field Effect Transistors).

[0031] Since the inverter power module assembly 41 includes multiple semiconductor switching elements, an overcurrent protection means is required to prevent deterioration or destruction of the semiconductor switching elements due to an overcurrent caused by an output short circuit or the like. For this reason, an overcurrent protection device 42 is also housed in the electrical equipment box 32 as overcurrent protection means. The overcurrent protection device 42 stops output when the output current exceeds a threshold value. The overcurrent protection device 42 can be configured, for example, with a transistor and a resistor, but is not limited to this.

[0032] Various manual switches, wiring, lamps, etc. are also contained inside the electrical equipment box 32. The inverter power module assembly 41 is provided with a module for measuring inverter overheating at the location where thermal grease is applied, and a sensor built into the module can detect the temperature inside the electrical equipment box.

[0033] 4, one control board 40, two inverter power module assemblies 41, and two overcurrent protection devices 42 are mounted on one board of a predetermined size made of plastic resin. The plastic resin is, for example, phenol resin, epoxy resin, polyimide resin, or the like.

[0034] The electrical equipment box 32 is attached to the sheet metal constituting the casing 30 of the outdoor unit 20. As shown in FIG. 5 , the interior of the electrical equipment box 32 is closed by a lid 43. To prevent heat generated by the electrical components from accumulating inside the electrical equipment box 32, the electrical equipment box 32 has vents on the bottom and upper side when attached to the casing 30. Air flows in through the vent 44 on the bottom side, passes through the interior, and is exhausted through the vent 45 on the upper side. The vent 44 is not limited to being located on the bottom, but may also be located on the lower side, and the vent 45 is not limited to being located on the upper side, but may also be located on the upper (top) side. The number of vents 44 and 45 is not limited to one each, but two or more may be provided. In this case, air flows both inside and outside the electrical equipment box 32. However, a configuration in which air flows only inside the electrical equipment box 32 through the vents 44 and 45 may also be used.

[0035] The electrical equipment box 32 is not limited to a structure that allows air to circulate as described above, and may be a completely sealed structure that uses a refrigerant from a heat exchange system for cooling. In this case, air circulates only outside the electrical equipment box 32.

[0036] Electrical components such as the control board 40, inverter power module assembly 41, and overcurrent protection device 42 include semiconductor elements, wiring, etc., which have electrical resistance, and therefore generate heat when power is supplied and they operate, causing their temperature to rise. However, air flows through the electrical equipment box 32 from the bottom vent 44 to the upper side vent 45, cooling these electrical components and preventing their temperature from rising.

[0037] The inverter power module assembly 41 is a power semiconductor that controls and converts electric power. A large current flows through it, generating a large amount of heat. Therefore, ventilation through the vents 44 and 45 alone is not sufficient to suppress temperature rise. Therefore, a heat sink 46 having multiple fins is provided on the outer surface of the electrical equipment box 32 as a heat dissipation means for dissipating heat generated by the inverter power module assembly 41. The heat sink 46 comes into contact with the air flowing from the bottom to the top of the outer surface of the electrical equipment box 32, dissipating the heat generated by the inverter power module assembly 41. The heat sink 46 can be provided not only for the inverter power module assembly 41 but also for the overcurrent protection device 42, through which a large current flows. The heat sink 46 may also be provided for electrical components other than the inverter power module assembly 41 and the overcurrent protection device 42.

[0038] 6 is a diagram illustrating the structure, mounting position, and mounting method of the heat sink 46. Electrical components such as the inverter power module assembly 41 are mounted on one surface (mounting surface) of one substrate 47. In the example shown in FIG. 6, a surface 47a on the back side of the mounting surface on which the electrical components of the substrate 47 are mounted is shown, and the inverter power module assembly 41 also protrudes from the back surface 47a of the substrate 47.

[0039] The substrate 47 can be attached to a resin case 48 made of plastic resin, but is not limited to this. Therefore, the substrate 47 does not have to be attached to the resin case 48 and can be attached to any material. When attaching the substrate 47 to the resin case 48, the resin case 48 has a rectangular hole 48a into which the portion of the substrate 47 protruding from the back surface 47a can be inserted, and a frame 48b into which the base portion 46a of the heat sink 46 is fitted. The base portion 46a of the heat sink 46 is fitted into the frame 48b of the resin case 48, and the heat sink 46 is fixed to the resin case 48 using fastening means such as bolts.

[0040] The base portion 46a of the heat sink 46 is exposed through the hole 48a in the resin case 48, but the hole 48a is closed because the portion of the inverter power module assembly 41 that protrudes from the back surface 47a of the substrate 47 is inserted into the hole 48a in the resin case 48. Note that by inserting the portion of the inverter power module assembly 41 that protrudes from the back surface 47a of the substrate 47 into the hole 48a, the flat surface of the protruding portion of the inverter power module assembly 41 comes into contact with the flat surface of the base portion 46a of the heat sink 46 that faces the hole 48a in the resin case 48.

[0041] As a result, heat generated during operation of the inverter power module assembly 41 is transferred through the base 46a of the heat sink 46 to the multiple fins 46b provided on the surface of the resin case 48 opposite the holes 48a, and then flows between the fins 46b, giving up the heat to the air that comes into contact with the fins 46b, thereby enabling the heat to be dissipated. The inverter power module assembly 41 includes multiple switching elements that are switched on and off in short cycles, generating a lot of heat and easily exceeding the upper limit of operating temperature. For this reason, the inverter power module assembly 41 is provided with the heat sink 46 to ensure its operation.

[0042] The fins 46b are metal plates arranged at predetermined intervals in a direction perpendicular to the flat surface of the base 46a opposite the holes 48a, and the heat transfer area is ensured by increasing the number of fins 46b. The base 46a is also a metal plate like the fins 46b, but its size and thickness are different.

[0043] 7 shows an example in which thermal grease is applied between the electrical component and the heat sink. The inverter power module assembly 41 and the heat sink 46 may be fixed to the resin case 48 in such a way that the flat surface of the protruding portion of the inverter power module assembly 41 as the electrical component directly contacts the flat surface of the base portion 46a of the heat sink 46, but it is difficult to form the two flat surfaces so that there is no gap between them.

[0044] As a result, a gap occurs between the flat surfaces of the two, increasing the heat transfer resistance between the inverter power module assembly 41 and the heat sink 46, making it impossible to properly transfer heat from the inverter power module assembly 41 to the heat sink 46.

[0045] Therefore, a thermal grease 49 is provided between the flat surfaces of both components, thereby reducing the heat transfer resistance between them and enabling the heat from the inverter power module assembly 41 to be transferred to the heat sink 46 appropriately.

[0046] Thermal grease 49 is a grease (lubricant) used to promote thermal conduction between contact surfaces. It fills gaps, eliminating air gaps and preventing heat transfer resistance due to air gaps. Thermal grease 49 is based on modified silicone, which has little change in viscosity with temperature, and can contain metal or metal oxide particles with high thermal conductivity as a filler. Examples of fillers include copper, silver, aluminum, aluminum oxide, and magnesium oxide.

[0047] Incidentally, when the heating operation of the air conditioner 10 stops, it goes into standby mode and the outdoor fan 26 stops, which stops the intake of air into the casing 30 and stops the air flow inside the electrical equipment box 32. Since the electrical components inside the electrical equipment box 32 no longer receive power and stop operating, they no longer generate heat, but since there is no air flow, they are indirectly cooled by the outside air and their temperature drops.

[0048] A minimum operating temperature is set for each electrical component inside the electrical equipment box 32, but depending on the region where the air conditioner 10 is provided, the outside air temperature may fall below this minimum operating temperature, causing the temperature inside the electrical equipment box 32 to fall below this minimum operating temperature during standby. This makes it impossible to guarantee the operation of each electrical component, reducing reliability.

[0049] Therefore, a heater is provided as a heating means within the electrical equipment box 32, and the temperature inside the electrical equipment box 32 can be heated and adjusted so that it does not fall below the lower limit temperature for use.

[0050] During heating operation of the air conditioner 10, the electrical components in the electrical equipment box 32 are supplied with power and are in operation, so they generate heat, but air that has been cooled by the outdoor heat exchanger 25 and is at a lower temperature than the outside air circulates inside and outside the electrical equipment box 32, so that the electrical equipment box 32 is constantly cooled. For this reason, during heating operation, the temperature inside the electrical equipment box 32 is lower than during standby.

[0051] When heating a fixed amount of heat, the temperature inside the electrical equipment box 32 is lower during heating operation, so not much heat is needed for heating during standby, but a fixed amount of heat is needed, so the amount of heat may be excessive, and when heating operation is performed, heat is needed for heating, but only a fixed amount is heated, so the amount of heat may be insufficient. This results in a large difference in temperature rise depending on whether the unit is operating, and the degree of temperature rise varies greatly.

[0052] If the temperature difference inside the electrical equipment box 32 during heating operation and standby can be reduced, it is believed that the excess heat during standby and the lack of heat during heating operation can be eliminated, and the variation in the degree of temperature rise depending on whether the unit is operating or not can be reduced.

[0053] The temperature difference inside the electrical equipment box 32 during heating operation and standby is mainly caused by the fact that during heating operation, the outdoor fan 26 circulates low-temperature air inside and / or outside the electrical equipment box 32, constantly cooling the electrical components. Therefore, if the cooling of the electrical components due to air circulation can be reduced, it is thought that the temperature difference inside the electrical equipment box 32 during heating operation and standby can be reduced.

[0054] Therefore, in order to transfer the heat of the heater directly or indirectly, the heater is configured to be in direct contact with the electrical component that needs to be heated, or to be in contact with the electrical component via some other member.

[0055] Here, the electrical components that require heating are those necessary for controlling the operation of the air conditioning device 10, such as the control board 40, the inverter power module assembly 41, and the overcurrent protection device 42, but the inverter power module assembly 41 in particular has a high minimum operating temperature.

[0056] Furthermore, by detecting the temperature inside the electrical equipment box 32, the outside air temperature, etc. and adjusting the amount of heat to match the target temperature, it is possible to reduce the amount of heat required for heating during standby, thereby eliminating excess heat, and to increase the amount of heat required for heating during heating operation, thereby eliminating insufficient heat. The amount of heat can be adjusted using control logic or a PTC (Positive Temperature Coefficient) heater with a self-temperature control function. The control logic can be implemented on a control board or other control circuit.

[0057] 8 is a diagram illustrating a first example of the shape of the heater 50, and the mounting position and mounting method of the heater 50 on the heat sink 46. The target electrical component is, for example, an inverter power module assembly 41. Note that this is just one example and is not limiting.

[0058] The inverter power module assembly 41 is in contact with the heat sink 46 directly or via thermal grease 49. Therefore, heat generated during operation of the inverter power module assembly 41 can be transferred to the heat sink 46 and dissipated from the heat sink 46. This means that if heat is applied to the heat sink 46, the heat can also be transferred from the heat sink 46 to the inverter power module assembly 41.

[0059] Therefore, by attaching the heater 50 to the heat sink 46 , the heater 50 can heat the heat sink 46 , and the heat of the heat sink 46 can be transferred to the inverter power module assembly 41 .

[0060] The heat sink 46 has a flat base 46a with a predetermined thickness and a plurality of fins 46b protruding from the base 46a. Even if the heater 50 is attached to the fins 46b, the fins 46b will come into contact with the circulating air and be cooled, resulting in the heat dissipation of the heater 50. For this reason, it is desirable to attach the heater 50 to the base 46a.

[0061] Therefore, a hole 46c of a predetermined diameter and length can be formed in the center of the thickness of the base portion 46a, and the heater 50 can be made cylindrical and rod-shaped with a diameter and length that can be inserted into the hole 46c.

[0062] The holes 46c extend in the longitudinal direction of the base portion 46a, i.e., in the width direction, and two holes 46c are provided spaced a predetermined distance apart in the shorter direction of the base portion 46a, i.e., in the height direction. Here, two holes 48a are provided, but the number is not limited to two and may be one, or three or more. Furthermore, the holes 46c are not limited to those extending in the width direction and may also extend in the height direction.

[0063] The heater 50 can be attached to the heat sink 46 by inserting it into a hole 46c in the base portion 46a. The heater 50 is rod-shaped and has a fixed diameter, but has an expanded end, so that it can be inserted until the expanded end abuts the base portion 46a. An electric wire 51 for supplying current is connected to the expanded end of the heater 50.

[0064] With this structure, current is supplied to the heater 50, and the heat generated by the heater 50 is transferred to the heat sink 46, and then transferred from the heat sink 46 to the inverter power module assembly 41 via the thermal grease 49, thereby heating the inverter power module assembly 41.

[0065] The hole 46c in the base portion 46a may have any shape and any length. Therefore, the shape and length of the heater 50 may also be any shape and length that matches the shape and length of the hole 46c. However, the diameter of the hole 46c must be smaller than the thickness of the base portion 46a.

[0066] 9 is a diagram illustrating a second example of the shape of the heater 50 and the mounting position and mounting method of the heater 50 to the heat sink 46. As long as the heat of the heater 50 can be transferred to the heat sink 46, the mounting method is not limited to a method in which a hole 46c is formed in the base portion 46a of the heat sink 46 and a rod-shaped heater 50 is inserted into the hole 46c.

[0067] The base portion 46a has two side surfaces at both ends in the width direction and a bottom surface and a top surface at both ends in the height direction. As shown in Fig. 9, the heater 50 can be made into a planar (sheet) shape and attached to each of the two side surfaces of the base portion 46a. In this case, the heater 50 transfers heat to the heat sink 46 via the two side surfaces.

[0068] The heater 50 is not limited to being attached to the two side surfaces at both ends in the width direction, but may be attached to one of the two side surfaces, or to one of the top and bottom surfaces at both ends in the height direction, or to both the top and bottom surfaces.

[0069] 10 is a diagram illustrating a third example of the shape of the heater 50 and the mounting position and mounting method of the heater 50 on the heat sink 46. The base portion 46a has four side surfaces, an upper surface, a lower surface, and a surface on which a plurality of fins 46b are mounted. The base portion 46a further has a surface facing the hole 48a in the resin case 48, i.e., a surface opposite the flat surface of the protruding portion of the inverter power module assembly 41.

[0070] For this reason, the heater 50 can be disposed between the inverter power module assembly 41 and the base portion 46a, and the gap therebetween can be filled with thermal grease 49. In this way, the heat of the heater 50 can be transferred directly to the inverter power module assembly 41 without going through the heat sink 46.

[0071] With the above-described configuration, the multiple fins 46b can suppress the temperature rise due to heat generation from the inverter power module assembly 41, and the heater 50 can maintain the temperature of the inverter power module assembly 41 at a constant level or higher even when the outside air temperature is low.

[0072] The heater 50 can be controlled to maintain the temperature of the inverter power module assembly 41 at a constant level or higher by controlling the heater 50 ON / OFF or adjusting the amount of heat generated, but the ON / OFF control or adjustment of the amount of heat generated can use the operating state of the outdoor unit 20 or a value from a sensor that detects the outdoor air temperature (outdoor air temperature). The outdoor unit 20 already has a sensor that detects the outdoor air temperature, so there is no need to provide an additional sensor.

[0073] The operating state of the outdoor unit 20 indicates whether the outdoor unit 20 is operating, whether the outdoor fan 26 is running, and whether air is circulating inside the casing 30. During heating operation, the outdoor heat exchanger 25 of the outdoor unit 20 functions as an evaporator, so that air taken in from outside exchanges heat with the refrigerant and is cooled. As a result, the cooled air circulates outside the electrical equipment box 32, inside the electrical equipment box 32, or both. Even if the electrical components inside the electrical equipment box 32 are operating and generating heat, the air may be cooled even more, causing the temperature to fall below the minimum operating temperature.

[0074] When the outdoor unit 20 is not operating, the outside air temperature cools the air inside the casing 30 through the casing 30, cools the air inside the electrical equipment box 32, and also cools the electrical components inside the electrical equipment box 32. As a result, there is a risk that the electrical components inside the electrical equipment box 32 may fall below their minimum operating temperature.

[0075] For these reasons, the heater 50 is controlled to turn on and off and adjust the heat generation amount using values from sensors that detect the operating state of the outdoor unit 20 and the outdoor air temperature. Specific control will be described in detail with reference to FIG. 11.

[0076] 11 is a flowchart showing an example of heating control by the heater 50. Regardless of whether the outdoor unit 20 is operating or stopped, the outdoor unit 20 is connected to a power source and power is supplied to the control board 40, and control begins from step 100. Here, the heating control is described as being performed by the control board 40, but heating control may also be performed by another control circuit or the like.

[0077] In step 101, it is determined whether the outdoor unit 20 is operating and the outdoor fan 26 is ON. If the outdoor unit 20 is operating, the outdoor fan 26 is ON, and the process proceeds to step 102 to determine whether the component temperature, i.e., the temperature of the inverter power module assembly 41, satisfies the heater ON condition. The component temperature of the electrical component is taken as the temperature inside the electrical component box 32. If it is determined that the heater ON condition is not met, the process returns to step 101.

[0078] If the outdoor unit 20 is not operating in step 101, it is stopped, and the process proceeds to step 103, where it is determined whether or not the value detected by the sensor that detects the outdoor air temperature satisfies the heater ON condition. If it is determined that the heater ON condition is not met, the process returns to step 101.

[0079] If it is determined in steps 102 and 103 that the heater ON conditions are met, the process proceeds to step 104, where the heater 50 is turned ON. That is, heating by the heater 50 is started.

[0080] After heating by the heater 50 has started, the amount of heat generated by the heater 50 can be adjusted. When the outdoor unit 20 is in operation, the amount of heat generated can be adjusted based on the temperature inside the electrical equipment box 32, and when the outdoor unit 20 is not in operation (standby), the amount of heat generated can be adjusted based on the outside air temperature (ambient temperature of the outdoor unit 20). During heating operation, the temperature inside the electrical equipment box 32 is lower than during standby, so the amount of heat generated can be adjusted to be larger during heating operation and smaller during standby.

[0081] In step 105, it is determined whether the component temperature satisfies the heater-off condition. If it is determined that the heater-off condition is not met, the determination in step 105 is repeated until the heater-off condition is met. The heater 50 remains ON until the heater-off condition is met.

[0082] If it is determined in step 105 that the heater OFF conditions are met, the process proceeds to step 106, where the heater 50 is turned OFF. Then, the process proceeds to step 107, where the control ends. Although the control ends here, it is possible to immediately start the control from step 100. This allows a determination to be made again as to whether the heater ON conditions are met, and if it is determined that the heater ON conditions are met, the heater 50 can be turned ON. This control makes it possible to maintain the temperature of the inverter power module assembly 41 at a constant level or higher.

[0083] Here, the heater ON condition and heater OFF condition will be explained. The heater 50 can use the lower limit operating temperature of the inverter power module assembly 41 as the reference temperature for the condition (heater ON condition) for turning the heater 50 ON. However, in actual control, the temperature fluctuates, and there is a high possibility that the temperature will fall below the lower limit operating temperature. Therefore, taking into consideration some fluctuation in temperature, a margin of, for example, about 5°C can be set above the lower limit operating temperature as the reference temperature (lower limit temperature) for the heater ON condition. Note that the margin is not limited to 5°C, but may be 10°C, for example.

[0084] The heater 50 can use the upper limit operating temperature of the inverter power module assembly 41 as the reference temperature for the condition for turning the heater 50 off (heater-off condition). However, because the upper limit operating temperature is a temperature exceeding 50°C, the heater 50 does not turn off until a considerable amount of time has passed, resulting in unnecessary power consumption. Therefore, a temperature 15 to 20°C higher than the reference temperature for the heater-on condition can be set as the reference temperature (upper limit temperature) for the heater-off condition. Note that the temperature higher than the reference temperature for the heater-on condition is not limited to 15 to 20°C, and may be 20 to 30°C, etc., as long as it does not exceed the upper limit operating temperature.

[0085] As explained above, the control device and heat exchange system of the present invention can dissipate heat generated by electrical components, making it easier to maintain the temperature of electrical components at a constant level or higher when the outside air temperature is low. Therefore, it is possible to select electrical components even when it is unavoidable to maintain a temperature range when selecting electrical components, or when the minimum operating temperature is relatively high for overall cost reduction purposes. Furthermore, because heat can be transferred directly to the electrical components, the energy required for heating can be reduced.

[0086] The control device and heat exchange system of the present invention have been described in detail using the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments and can be modified within the scope of what a person skilled in the art can conceive, such as other embodiments, additions, modifications, deletions, etc., and any aspect is within the scope of the present invention as long as it achieves the functions and effects of the present invention.

[0087] Therefore, according to the present invention, (1) a control device can be provided that controls a heat exchange system including a blowing means that takes in and exhausts air that exchanges heat with a refrigerant, the control device including one or more electrical components that control the heat exchange system, an electrical equipment box that houses the one or more electrical components and in which air circulates inside, outside, or both by the blowing means, heat dissipation means that protrudes from the outer surface of the electrical equipment box and dissipates heat generated by at least one of the one or more electrical components, and heating means that heats at least one of the one or more electrical components directly or via the heat dissipation means, and that controls heating by the heating means based on whether the heat exchange system is operating and the temperature inside the electrical equipment box or the ambient temperature around the heat exchange system.

[0088] According to the present invention, (2) it is possible to provide a control device as described in (1) above, in which at least one of the one or more electrical components is a load adjustment means for adjusting the operating load of the heat exchange system, and the heat dissipation means is in contact with the load adjustment means via thermally conductive grease.

[0089] According to the present invention, (3) it is possible to provide a control device as described in (2) above, in which the heat dissipation means has one or more insertion holes having a predetermined diameter and a predetermined depth, a base portion that contacts the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins provided on the base portion, and the heating means is inserted into the one or more insertion holes of the base portion.

[0090] According to the present invention, (4) it is possible to provide a control device as described in (2) above, in which the heat dissipation means has a base portion that contacts the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins provided on the base portion, and the heating means is arranged adjacent to the side of the base portion.

[0091] According to the present invention, (5) it is possible to provide a control device as described in (2) above, in which the heat dissipation means has a base portion that is in contact with the load adjustment means across the thermal conductive grease, and a plurality of fins provided on the base portion, and the heating means is arranged between the load adjustment means and the base portion and is embedded in the thermal conductive grease.

[0092] According to the present invention, (6) it is possible to provide a control device as described in any of (2) to (5) above, in which the control means starts heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature detected by an outside air temperature detection means provided in the heat exchange system for detecting the outside air temperature falls below a set lower limit temperature.

[0093] According to the present invention, (7) it is possible to provide a control device as described in (6) above, in which the control means stops heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature becomes equal to or higher than a set upper limit temperature after starting heating by the heating means.

[0094] According to the present invention, (8) a heat exchange system including the control device according to any one of (1) to (7) above can be provided.

[0095] According to the present invention, (9) a heat exchange system as described in (7) above can be provided, which includes an indoor unit that exchanges heat between indoor air as a fluid and the refrigerant, and an outdoor unit that circulates the refrigerant and exchanges heat between outside air and the refrigerant, and the outdoor unit includes the blowing means that takes in the outside air, exchanges heat with the refrigerant, and then discharges the outside air, and the control device. [Explanation of symbols]

[0096] 10...Air conditioning equipment 11...Indoor unit 12…Indoor heat exchanger 13...Indoor fan 14...Indoor fan motor 20...Outdoor unit 21...Compressor 22...Accumulator 23...Four-way valve 24...Expansion valve 25...Outdoor heat exchanger 26...Outdoor fan 27...Outdoor fan motor 28...Control device 30...Casing 31…Machine room 32...Electrical equipment box 33...First Space 34...Second Space 40...Control board 41...Inverter power module assembly 42...Overcurrent protection device 43…Lid 44, 45...Ventilation holes 46...heat sink 46a...base part 46b…Fin 46c...hole 47... Circuit board 47a...side 48...Resin case 48a...hole 48b...frame 49...Thermal grease 50...Heater 51...Electric wire

Claims

1. A control device for controlling the operation of a heat exchange system including a blower that takes in and discharges air that exchanges heat with a refrigerant, one or more electrical components for controlling the heat exchange system; an electrical equipment box that houses the one or more electrical components therein and that allows air to circulate between the inside and / or the outside by the air blowing means; a heat dissipation means protruding from an outer surface of the electrical equipment box to dissipate heat generated by at least one of the one or more electrical components; a heating means for heating at least one of the one or more electrical components directly or via the heat dissipation means; Including, a control device that controls heating by the heating means based on whether the heat exchange system is operating or not, and the temperature inside the electrical equipment box or the ambient temperature around the heat exchange system.

2. At least one of the one or more electrical components is a load adjusting means for adjusting an operating load of the heat exchange system, 2. The control device according to claim 1, wherein the heat dissipation means is in contact with the load adjustment means with thermally conductive grease sandwiched therebetween.

3. the heat dissipation means has one or more insertion holes having a predetermined diameter and a predetermined depth, a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; The control device according to claim 2 , wherein the heating means is inserted into the one or more insertion holes of the base portion.

4. the heat dissipation means has a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; The control device according to claim 2 , wherein the heating means is disposed adjacent to a side surface of the base portion.

5. the heat dissipation means has a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; 3. The control device according to claim 2, wherein the heating means is disposed between the load adjusting means and the base portion and is embedded in the thermally conductive grease.

6. The control device according to any one of claims 2 to 5, wherein the control means starts heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature detected by an outside air temperature detection means provided in the heat exchange system, which detects the outside air temperature, falls below a set lower limit temperature.

7. 7. The control device according to claim 6, wherein the control means stops the heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature becomes equal to or higher than a set upper limit temperature after the heating by the heating means starts.

8. A heat exchange system for exchanging heat between a fluid and a refrigerant, The heat exchange system includes: a blowing means for taking in and discharging air that exchanges heat with the refrigerant; The control device one or more electrical components for controlling the heat exchange system; an electrical equipment box that houses the one or more electrical components therein and that allows air to circulate between the inside and / or the outside by the air blowing means; a heat dissipation means protruding from an outer surface of the electrical equipment box to dissipate heat generated by at least one of the one or more electrical components; a heating means for heating at least one of the one or more electrical components directly or via the heat dissipation means; Including, A heat exchange system that controls heating by the heating means based on whether the heat exchange system is operating or not, and the temperature inside the electrical equipment box or the ambient temperature around the heat exchange system.

9. At least one of the one or more electrical components is a load adjusting means for adjusting an operating load of the heat exchange system, 9. The heat exchange system according to claim 8, wherein the heat dissipation means is in contact with the load adjustment means with thermally conductive grease sandwiched therebetween.

10. the heat dissipation means has one or more insertion holes having a predetermined diameter and a predetermined depth, a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; The heat exchange system according to claim 8 , wherein the heating means is inserted into the one or more insertion holes of the base portion.

11. the heat dissipation means has a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; The heat exchange system of claim 8 , wherein the heating means is disposed adjacent a side of the base portion.

12. the heat dissipation means has a base portion that is in contact with the load adjustment means with the thermal conductive grease sandwiched therebetween, and a plurality of fins that are provided on the base portion; 9. The heat exchange system according to claim 8, wherein the heating means is disposed between the load adjusting means and the base portion and is embedded in the thermally conductive grease.

13. A heat exchange system as described in any one of claims 8 to 12, wherein the control means starts heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature detected by an outside air temperature detection means provided in the heat exchange system for detecting the outside air temperature falls below a set lower limit temperature.

14. The heat exchange system according to claim 13, wherein the control means stops heating by the heating means when the temperature inside the electrical equipment box or the outside air temperature becomes equal to or higher than a set upper limit temperature after starting heating by the heating means.

15. The heat exchange system includes an indoor unit that performs heat exchange between indoor air as the fluid and the refrigerant, and an outdoor unit that circulates the refrigerant and performs heat exchange between outdoor air and the refrigerant, The heat exchange system according to claim 13 , wherein the outdoor unit includes the blower that takes in the outside air, exchanges heat with the refrigerant, and then discharges the outside air, and the control device.

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