Compressor auxiliary heating start control method, compressor auxiliary heating start system and air conditioner

Abstract

The application provides a compressor auxiliary heating starting control method, a compressor auxiliary heating starting system and an air conditioner. The control method comprises the following steps: when the compressor stops, the lubricating oil in the compressor, which absorbs the heat of the components of the compressor, is introduced into a heat preservation device; when a starting instruction is received, the temperature T1 of the lubricating oil in the heat preservation device, the temperature T2 of the compressor, the volume V1 of the liquid in the heat preservation device and the volume V2 of the liquid in the compressor are detected; it is determined whether V2>0 and T2

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and in particular to a compressor auxiliary heating start control method, compressor auxiliary heating start system, and air conditioner. Background Technology

[0002] Currently, compressors used in outdoor units of air conditioners require auxiliary heating devices to ensure normal startup under various low-temperature conditions. These devices heat the compressor's internal temperature, causing the low-temperature liquid refrigerant inside to absorb heat and vaporize, thus ensuring the compressor meets the prerequisites for normal startup. A common auxiliary heating device involves adding an electric heating strip to the outside of the compressor casing. This strip heats the casing, which in turn conducts heat to the lubricating oil inside the compressor. The heated oil mixes with the liquid refrigerant, exchanging heat and causing the refrigerant to vaporize. While this auxiliary heating device is simple in structure and easy to implement, the electric heating strip must be turned on frequently and for extended periods when the compressor is in standby mode or frequently starting. This accelerates the aging of the heating strip, shortens its lifespan, and increases the air conditioner's energy consumption and operating costs.

[0003] A technology has emerged that controls the activation of the electric heating element based on the compressor surface temperature. This technology shortens the start-up time of the electric heating element, thereby reducing its wear. However, in this technology, the electric heating element is still installed on the surface of the compressor housing. Therefore, it does not solve the problem of large actual heat loss and low heating efficiency caused by the electric heating element being located on the outside of the compressor housing and indirectly heating the lubricating oil inside the housing by heating the compressor housing. Summary of the Invention

[0004] This invention proposes a compressor auxiliary heating start control method and a compressor auxiliary heating start system and air conditioner using the same method, in order to solve the technical problem in the prior art where the compressor indirectly heats the lubricating oil inside the casing by heating its outer casing with an electric heating belt, resulting in low efficiency in heating and vaporizing the liquid refrigerant.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0006] This invention provides a compressor auxiliary heating start-up control method, comprising:

[0007] S1: When the compressor stops, the lubricating oil that has absorbed the heat from the compressor components is introduced into the insulation device.

[0008] S2: When a start-up command is received, detect the lubricating oil temperature T1 in the insulation device, the compressor temperature T2, the liquid volume V1 in the insulation device, and the liquid volume V2 in the compressor.

[0009] S3: Determine whether V2 > 0 and T2 < refrigerant liquefaction temperature T3 are satisfied simultaneously. If so, continue to the next step.

[0010] S4: Calculate the temperature T0 of the mixture after the lubricating oil in the heat preservation device is introduced into the compressor and mixed with the liquid refrigerant based on the detected T1, T2, V1 and V2 data, and determine whether T0≥T3. If yes, continue to the next step.

[0011] S5: Introduce the lubricating oil from the insulation device into the compressor;

[0012] S6: Start the compressor.

[0013] Preferably, if it is determined in S4 that T0 < T3, then the minimum temperature T1' of the lubricating oil required to satisfy T0 ≥ T3 is calculated based on the detected T1, T2, V1 and V2 data, and the lubricating oil in the heat preservation device is heated to T1 ≥ T1', and then S5 is executed;

[0014] Preferably, S1 includes:

[0015] When the compressor stops, open the switch valve on the pipette connecting the compressor and the insulation device to introduce the lubricating oil from the compressor into the insulation device until V2 = 0 is detected, then close the switch valve.

[0016] Preferably, S5 includes:

[0017] Open the switch valve on the pipette connecting the compressor and the insulation device and start the oil pump to draw the lubricating oil in the insulation device into the compressor until V1=0 is detected. Then close the switch valve and stop the oil pump, and proceed to S6.

[0018] Preferably, if it is determined in S3 that V2 > 0 and T2 < refrigerant liquefaction temperature T3 are not simultaneously satisfied, then S5 is executed.

[0019] The present invention also provides a compressor auxiliary heating start system, comprising:

[0020] Insulation device;

[0021] Liquid transfer tubing is used to connect the corresponding internal liquid storage space of the compressor and the insulation device;

[0022] On / off valves are used to control the opening and closing of pipetting lines;

[0023] An oil pump is used to draw lubricating oil from the insulation device into the compressor through a transfer pipe.

[0024] Temperature detection device, used to detect the temperature T1 of the lubricating oil in the insulation device and the temperature T2 in the compressor;

[0025] A volume detection device is used to detect the liquid volume V1 inside the insulation device and the liquid volume V2 inside the compressor;

[0026] The control is transferred, and the above-mentioned compressor auxiliary heating start control method is used to control the above-mentioned components.

[0027] Furthermore, the compressor auxiliary heating start-up system also includes:

[0028] An auxiliary heating device is used to heat the lubricating oil inside the insulation device.

[0029] Preferably, the heat preservation device is a heat preservation tank.

[0030] Preferably, the switching valve is a solenoid valve.

[0031] The present invention also provides an air conditioner including the above-described compressor auxiliary heating start system.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The compressor auxiliary heating start-up control method, system, and air conditioner provided by this invention allow for the introduction of high-temperature, high-pressure lubricating oil from the compressor into an insulation device during compressor shutdown. This ensures that the lubricating oil reaches a certain temperature when the ambient temperature is low, either directly or through auxiliary heating. Before the compressor starts, the oil pump draws the lubricating oil back into the compressor, heating the liquid refrigerant at the bottom of the compressor with the higher-temperature lubricating oil. This causes the liquid refrigerant to rapidly absorb heat and vaporize, ensuring rapid compressor start-up in low-temperature environments. This compressor auxiliary heating start-up control method and system can directly control and regulate the lubricating oil temperature within the compressor. Compared to traditional electric heating systems that indirectly heat the lubricating oil via a heated outer casing, this system offers higher heating efficiency and eliminates the need for prolonged and frequent operation of auxiliary electric heating, resulting in more energy-efficient air conditioning systems. Attached Figure Description

[0034] To more clearly illustrate the technical solution proposed by the present invention, a detailed description is provided below in conjunction with the embodiments and accompanying drawings. It should be understood that the accompanying drawings described below are merely some embodiments of the present invention, and those skilled in the art can make changes to these drawings under the concept of the present invention.

[0035] Figure 1 A schematic block diagram of the logic flow of an embodiment of the compressor auxiliary heating start-up control method provided by the present invention;

[0036] Figure 2 This is a schematic diagram of the overall structure of an embodiment of the compressor auxiliary heating start-up system provided by the present invention.

[0037] The main markings in the attached figures are as follows:

[0038] 1. Insulation device; 2. Compressor; 3. Switch valve; 4. Liquid transfer pipeline; 5. Oil pump; 6. Auxiliary heating device. Detailed Implementation

[0039] To make the technical problem to be solved, the technical solution and the beneficial effects of the present invention clearer, the following description is provided in conjunction with the appendix. Figure 1-2 The present invention will be further described in detail with reference to embodiments.

[0040] Please see Figure 1 The compressor auxiliary heating start-up control method provided by the present invention includes:

[0041] S1: When compressor 2 stops, the lubricating oil that has absorbed the heat of the compressor 2 components is introduced into the heat preservation device 1;

[0042] S2: When the start command is received, detect the lubricating oil temperature T1 in the insulation device 1, the temperature T2 in the compressor 2, the liquid volume V1 in the insulation device 1 and the liquid volume V2 in the compressor 2.

[0043] S3: Determine whether V2 > 0 and T2 < refrigerant liquefaction temperature T3 are satisfied simultaneously. If so, continue to the next step.

[0044] S4: Calculate the temperature T0 of the mixture after all the lubricating oil in the insulation device 1 is introduced into the compressor 2 and mixed with the liquid refrigerant based on the detected T1, T2, V1 and V2 data, and determine whether T0≥T3. If yes, continue to the next step.

[0045] S5: Introduce all the lubricating oil in the insulation device 1 into the compressor 2;

[0046] S6: Start compressor 2.

[0047] In this embodiment, the lubricating oil has both lubricating and cooling effects on the components of the compressor 2 (especially the motor), and can be used as cooling oil for the motor of the compressor 2 at the same time.

[0048] In this embodiment, S1 includes:

[0049] When the compressor 2 stops, the switch valve 3 (preferably a solenoid valve) on the liquid transfer pipe 4 connecting the compressor 2 and the insulation device 1 is opened to introduce the high-temperature and high-pressure lubricating oil in the compressor 2 into the insulation device 1 until V2 = 0 is detected, and then the switch valve 3 (solenoid valve) is closed.

[0050] Specifically, during the operation of compressor unit 2, the motor inside generates a large amount of heat. Therefore, when compressor 2 stops, the temperature of its internal lubricating oil is relatively high. After the control module receives the signal that compressor 2 has completely stopped, it controls the solenoid valve to open. At this time, the pressure inside compressor 2 is much greater than the pressure inside insulation device 1. The higher internal pressure of compressor 2 can be used to introduce the high-temperature, high-pressure lubricating oil into insulation device 1. The heat absorbed by the lubricating oil when compressor 2 stops is maintained for a longer period of time through insulation device 1, so that it can be supplied to compressor 2 as needed to heat its low-temperature liquid refrigerant. This allows the low-temperature liquid refrigerant inside compressor 2 to absorb heat and vaporize, ensuring a smooth low-temperature auxiliary heating start-up of compressor 2. To ensure that the amount of lubricating oil in insulation device 1 (liquid volume V1 in insulation device 1) is as close as possible to the amount of lubricating oil in compressor 2 before the solenoid valve opens (liquid volume V2 in compressor 2), when V2 = 0 is detected, the control module controls the solenoid valve to close. At this time, under the insulation effect of insulation device 1, the heat loss and temperature drop of the lubricating oil are slow, and a high oil temperature can be maintained for a long time.

[0051] In this embodiment, in step S2, when the control module unit receives the instruction to start the compressor 2, the control temperature detection device and the volume detection device detect the lubricating oil temperature T1 in the insulation device 1, the temperature T2 in the compressor 2, the liquid volume V1 in the insulation device 1, and the liquid volume V2 in the compressor 2, and then proceed to the next step S3; in step S3, the control device first determines whether V2 > 0 (i.e., whether there is liquid refrigerant at the bottom of the compressor 2) and T2 < refrigerant liquefaction temperature T3 (i.e., whether the temperature T2 in the compressor 2 is less than the refrigerant liquefaction temperature T3) are simultaneously satisfied. If so, it is determined that there is liquid refrigerant at the bottom of the compressor 2, and the next step S4 is continued.

[0052] In this embodiment, the control device in S4 calculates the temperature T0 of the mixture formed by the lubricating oil and liquid refrigerant after all the lubricating oil in the heat preservation device 1 is introduced into the compressor 2, based on the detected T1, T2, V1 and V2 data, using the following formulas (1), (2) and (3) obtained according to the laws of thermodynamics:

[0053] C1*m1(T0-T1)=C2*m2(T2-T0) (1);

[0054] m1=V1*ρ3 (2);

[0055] m2=V2*ρ4 (3).

[0056] Where C1 is the specific heat capacity of the lubricating oil in the insulation device 1, C2 is the specific heat capacity of the refrigerant in the compressor 2, ρ3 is the density of the lubricating oil in the insulation device 1, ρ4 is the density of the liquid refrigerant in the compressor 2, m1 is the mass of the lubricating oil in the insulation device 1, m2 is the mass of the liquid refrigerant in the compressor 2, T1 is the temperature of the lubricating oil in the insulation device 1, T2 is the temperature in the compressor 2, V1 is the liquid volume in the insulation device 1, and V2 is the liquid volume in the compressor 2; the control device determines whether T0 ≥ T3, and if so, continues to the next step S5;

[0057] In this embodiment, S5 includes:

[0058] The control module controls the opening of the switch valve 3 (solenoid valve). At the same time, it controls the start of the oil pump in the insulation device 1, drawing all the lubricating oil in the insulation device 1 into the compressor 2. When the volume detection device detects V1=0, it is determined that the lubricating oil in the insulation device 1 has been completely drawn out. The switch valve 3 (solenoid valve) is then closed. At this time, the lubricating oil in the compressor 2 mixes with the liquid refrigerant, causing the mixed liquid refrigerant to absorb heat and rise to a temperature T0 greater than or equal to the refrigerant liquefaction temperature T3 (i.e., the refrigerant vaporization temperature). This causes the liquid refrigerant to absorb heat and vaporize. At this time, the compressor 2 can start without being affected by the liquid refrigerant. Therefore, the next step S6 is continued to start the compressor 2, thereby realizing the rapid start of the compressor 2 in a low-temperature environment.

[0059] In this embodiment, if it is determined that T0 < T3 in S4, the minimum temperature T1' of the lubricating oil required to satisfy T0 ≥ T3 is calculated based on the detected T1, T2, V1 and V2 data, and the lubricating oil in the heat preservation device 1 is heated to T1 ≥ T1', and then the next step S5 is executed.

[0060] Specifically, when the result of judging whether T0≥T3 in S4 is T0<T3, it is determined that the temperature T1 of the lubricating oil in the insulation device 1 is insufficient to heat the mixed liquid refrigerant to above T3 so that it can be sufficiently vaporized after the lubricating oil and liquid refrigerant are mixed in the compressor 2. Therefore, in order to ensure that the lubricating oil can be heated to a sufficient level of vaporization after being drawn from the insulation device 1 into the compressor 2 and mixed with the liquid refrigerant, the control module controls the auxiliary heating device 6 to be turned on to quickly heat the lubricating oil. The minimum lubricating oil temperature T1' required to satisfy T0≥T3 can be calculated by the above formulas (2), (3) and the following formula (4):

[0061] C1*m1(T1'-T3)=C2*m2(T3-T2) (4).

[0062] In fact, according to the above formulas, it can be calculated that when the temperature of the lubricating oil in the insulation device 1, T1 ≥ T1', T0 ≥ T3 can be satisfied; when the temperature of the lubricating oil in the insulation device 1, T1 < T1', then T0 < T3 and T0 ≥ T3 cannot be satisfied. Therefore, in S4, when the temperature detection device detects that the temperature of the lubricating oil in the insulation device 1, T1 ≥ T1', it is determined that the temperature of the lubricating oil in the insulation device 1, T1, is sufficient to heat the mixed liquid refrigerant to above T3 after the lubricating oil and liquid refrigerant are mixed in the compressor 2, so that it can be sufficiently vaporized, and the next step, S5, can be continued.

[0063] In one embodiment, if it is determined in S3 that V2 > 0 and T2 < refrigerant liquefaction temperature T3 are not simultaneously satisfied, it is determined that there is no liquid refrigerant accumulated at the bottom of the compressor 2 at this time. Therefore, there is no need to execute S4 at this time, and the process directly jumps to the execution step S5. After introducing the lubricating oil in the heat preservation device 1 into the compressor 2, the compressor 2 is started normally in step S6.

[0064] Please see Figure 2 The present invention also provides a compressor auxiliary heating start-up system, comprising:

[0065] Insulation device 1;

[0066] The liquid transfer pipe 4 is used to connect the compressor 2 and the corresponding internal liquid storage space of the insulation device 1;

[0067] Switch valve 3 is used to control the opening and closing of the pipetting line 4;

[0068] The oil pump 5 is used to draw lubricating oil from the heat preservation device 1 into the compressor 2 through the liquid transfer pipe 4.

[0069] Temperature detection device, used to detect the lubricating oil temperature T1 inside the heat preservation device 1 and the temperature T2 inside the compressor 2;

[0070] A volume detection device is used to detect the liquid volume V1 in the heat preservation device 1 and the liquid volume V2 in the compressor 2.

[0071] The control is switched, and the above-mentioned compressor auxiliary heating start control method is used to control the above-mentioned switching valve 3, oil pump 5, temperature detection device and volume detection device and other components.

[0072] In this embodiment, the control device can be the control device of an air conditioner.

[0073] In another embodiment, the control device can also be the control device integrated into the compressor auxiliary heating start system.

[0074] In a preferred embodiment, the temperature detection device includes temperature sensing bulbs respectively disposed in the heat preservation device 1 and the compressor 2.

[0075] In other embodiments, the temperature detection device may also use temperature sensors respectively located in the insulation device 1 and the compressor 2 to detect the temperature.

[0076] As a preferred embodiment, the volume detection device is a capacitive liquid level detection device, which detects the liquid level height inside the insulation device 1 (insulation tank) or at the bottom of the compressor 2 by means of capacitance characteristics, and then calculates the liquid volume V1 inside the insulation device 1 (insulation tank) and the liquid volume V2 inside the compressor 2 based on the structural features inside the insulation device 1 (insulation tank) or at the bottom of the compressor 2.

[0077] In other embodiments, the volume detection device may also be a mechanical liquid level detection device.

[0078] In this embodiment, the compressor auxiliary heating start-up system further includes:

[0079] Auxiliary heating device 6 is used to heat the lubricating oil in the heat preservation device 1.

[0080] In a preferred embodiment, the auxiliary heating device 6 is a mesh electric heating wire, which is located at the oil outlet of the oil pump 5 to ensure that the lubricating oil pumped by the oil pump 5 can be quickly heated to the specified temperature.

[0081] In this embodiment, the heat preservation device 1 is a heat preservation tank. As a preferred embodiment, the heat preservation tank has a double-layer vacuum insulation structure. As a more preferred embodiment, the double-layer tank body is made of stainless steel to ensure the heat preservation effect.

[0082] In this embodiment, the switching valve 3 is a solenoid valve.

[0083] In other embodiments, the switching valve 3 may also be a hydraulic valve, or the switching valve 3 may also be other types of valves to achieve the on / off action of the pipetting pipeline.

[0084] The present invention also provides an air conditioner including the above-described compressor auxiliary heating start system.

[0085] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the invention.

Claims

1. A method for controlling the auxiliary heating start-up of a compressor, characterized in that, include: S1: When the compressor stops, the lubricating oil that has absorbed the heat of the compressor components is introduced into the heat preservation device. S2: When a start-up command is received, detect the lubricating oil temperature T1 in the insulation device, the compressor temperature T2, the liquid volume V1 in the insulation device, and the liquid volume V2 in the compressor. S3: Determine whether V2 > 0 and T2 < refrigerant liquefaction temperature T3 are satisfied simultaneously. If so, continue to the next step. S4: Calculate the temperature T0 of the mixture after the lubricating oil in the heat preservation device is introduced into the compressor and mixed with the liquid refrigerant based on the detected T1, T2, V1 and V2 data, and determine whether T0≥T3. If yes, continue to the next step. S5: Introduce the lubricating oil from the insulation device into the compressor; S6: Start the compressor.

2. The compressor auxiliary heating start-up control method as described in claim 1, characterized in that, If it is determined in S4 that T0 < T3, then the minimum temperature T1' of the lubricating oil required to satisfy T0 ≥ T3 is calculated based on the detected T1, T2, V1 and V2 data, and the lubricating oil in the heat preservation device is heated to T1 ≥ T1', and then S5 is executed.

3. The compressor auxiliary heating start-up control method as described in claim 1, characterized in that, S1 includes: When the compressor stops, open the switch valve on the pipette connecting the compressor and the insulation device to introduce the lubricating oil from the compressor into the insulation device until V2 = 0 is detected, then close the switch valve.

4. The compressor auxiliary heating start-up control method as described in claim 1, characterized in that, S5 includes: Open the switch valve on the pipette connecting the compressor and the insulation device and start the oil pump to draw the lubricating oil in the insulation device into the compressor until V1=0 is detected. Then close the switch valve and stop the oil pump, and proceed to S6.

5. The compressor auxiliary heating start-up control method as described in claim 4, characterized in that, If it is determined in step S3 that V2 > 0 and T2 < refrigerant liquefaction temperature T3 are not simultaneously satisfied, then step S5 is executed.

6. A compressor auxiliary heating start-up system, characterized in that, include: Insulation device; Liquid transfer tubing is used to connect the corresponding internal liquid storage space of the compressor and the insulation device; A switching valve is used to control the on / off state of the pipetting line; An oil pump is used to draw the lubricating oil from the heat preservation device into the compressor through the liquid transfer pipe; Temperature detection device, used to detect the temperature T1 of the lubricating oil in the insulation device and the temperature T2 in the compressor; A volume detection device is used to detect the liquid volume V1 inside the insulation device and the liquid volume V2 inside the compressor; The control is transferred, and the above-mentioned components are controlled by the compressor auxiliary heating start control method as described in any one of claims 1-5.

7. The compressor auxiliary heating start-up system as described in claim 6, characterized in that, Also includes: An auxiliary heating device is used to heat the lubricating oil inside the insulation device.

8. The compressor auxiliary heating start-up system as described in claim 6, characterized in that, The heat preservation device is a heat preservation tank.

9. The compressor auxiliary heating start-up system as described in claim 6, characterized in that, The switching valve is a solenoid valve.

10. An air conditioner, characterized in that, Includes the compressor auxiliary heating start system as described in any one of claims 6-8.

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