Control method of air conditioning system

Abstract

The present application relates to the technical field of air conditioners, and specifically provides a control method of an air conditioning system, aiming at solving the problem of high energy consumption when a set of compressors drives multiple devices in the existing air conditioning system. To this end, the control method of the air conditioning system comprises: acquiring actual temperatures and preset temperatures of all running devices; adjusting the opening degree of the corresponding valve according to the actual temperature and the preset temperature of the device; and determining the running frequency of the compressor according to the opening degree of all valves. The opening degree of all valves can feedback the demand of all devices for refrigerant flow, and the smaller the demand for refrigerant flow is, the lower the running power requirement of the compressor is. By controlling the running frequency of the compressor according to the demand of all devices for refrigerant flow, the running frequency of the compressor can match the current state of all devices, and the refrigerant can be reasonably utilized according to the demand of each device, so as to improve the energy utilization efficiency.

Description

Technical Field

[0001] This invention relates to the technical field of air conditioning, and specifically provides a control method for an air conditioning system. Background Technology

[0002] There is currently an air conditioning system that includes one outdoor unit and two or more indoor units, with one outdoor unit driving two or more indoor units to work simultaneously.

[0003] For an air conditioning system that only performs cooling, it includes a compressor, a first heat exchanger, an expansion valve, and a second heat exchanger. The refrigerant flowing from the compressor outlet flows sequentially through the second heat exchanger, the expansion valve, and the first heat exchanger. The compressor compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The second heat exchanger liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant, releasing heat to the outside. The liquid refrigerant enters the expansion valve for throttling, then passes through the first heat exchanger to absorb heat, causing the liquid refrigerant to evaporate and form a gaseous state. It then re-enters the compressor for compression and pressurization, repeating this cycle. Cooling is achieved by absorbing heat through the first heat exchanger. The compressor, second heat exchanger, and expansion valve are all located in the outdoor unit, while the first heat exchanger is located in the indoor unit, with one first heat exchanger in each indoor unit.

[0004] The drawback of the aforementioned air conditioning system is that, due to the inconsistent operating conditions of multiple indoor units, the compressor is difficult to adjust using variable frequency technology. Otherwise, it may lead to erratic operation of the indoor units, resulting in unstable cooling or heating performance. Therefore, this type of air conditioning system generally operates at full load to ensure the stable operation of multiple indoor units, resulting in higher energy consumption.

[0005] Therefore, there is an urgent need for a control method for air conditioning systems to solve the problem of high energy consumption when existing air conditioning systems use one compressor to drive multiple devices. Summary of the Invention

[0006] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem of high energy consumption when existing air conditioning systems use one compressor to drive multiple devices.

[0007] In a first aspect, the present invention provides a control method for an air conditioning system, the air conditioning system including a compressor and at least two devices, the compressor being able to supply refrigerant to the devices via refrigerant pipelines for cooling or heating, and each of the refrigerant pipelines within the devices being equipped with valves capable of adjusting their opening degree; the control method for the air conditioning system includes: acquiring the actual temperature and preset temperature of all operating devices; adjusting the opening degree of the corresponding valves according to the actual temperature and preset temperature of the devices; and determining the operating frequency of the compressor according to the opening degree of all the valves.

[0008] In a specific implementation of the control method for the above-mentioned air conditioning system, "adjusting the opening degree of the corresponding valve according to the actual temperature and preset temperature of the equipment" includes: calculating and obtaining the difference between the actual temperature and the preset temperature of each of the equipment; and adjusting the opening degree of the corresponding valve according to the difference between the actual temperature and the preset temperature of the equipment.

[0009] In a specific implementation of the control method for the aforementioned air conditioning system, "determining the operating frequency of the compressor based on the opening degree of all the valves" includes: obtaining the pipe coefficient K for each device; obtaining the valve opening degree SZ corresponding to each device; calculating and obtaining the calculated opening degree of all the valves, wherein the calculated opening degree of all the valves is... Where x is the total number of devices connected to the compressor; the operating frequency of the compressor is adjusted according to the calculated opening degree of all the valves.

[0010] In a specific implementation of the control method for the above-mentioned air conditioning system, "adjusting the operating frequency of the compressor according to the calculated opening degree of all the valves" includes: if the calculated opening degree of all the valves is greater than a first preset opening degree, then the compressor operates at a first frequency.

[0011] In a specific implementation of the control method for the above-mentioned air conditioning system, "adjusting the operating frequency of the compressor according to the calculated opening degree of all the valves" further includes: if the calculated opening degree of all the valves is less than the second preset opening degree, then the compressor operates at a third frequency.

[0012] In a specific implementation of the control method for the above-mentioned air conditioning system, "adjusting the operating frequency of the compressor according to the calculated opening degree of all the valves" further includes: if the calculated opening degree of all the valves is greater than the second preset opening degree and less than the first preset opening degree, then the compressor operates at the second frequency.

[0013] In a specific embodiment of the control method for the above-mentioned air conditioning system, the air conditioning system is applied to a vehicle, and the compressor includes a first compressor and a second compressor. The first compressor is driven by the vehicle's engine, and the second compressor is driven by the vehicle's battery. The air conditioning system also includes a reversing valve, which is connected to the first compressor and the second compressor via a pipe. At least one of the devices is a shared device, and switching the reversing valve enables either the first compressor or the second compressor to supply refrigerant to the shared device. The control method for the air conditioning system further includes: acquiring the engine speed; controlling the first compressor or the second compressor to operate based on the engine speed; and switching the reversing valve so that one of the first compressor and the second compressor in operation supplies refrigerant to the shared device.

[0014] In a specific implementation of the control method for the aforementioned air conditioning system, "controlling the operation of the first compressor or the second compressor according to the engine speed, and switching the reversing valve to allow one of the first compressor and the second compressor to deliver refrigerant to the shared equipment" includes: if the engine speed is not lower than a preset value, then starting the first compressor and switching the reversing valve to allow the first compressor to deliver refrigerant to the shared equipment; and / or, if the engine speed is lower than the preset value, then starting the second compressor and switching the reversing valve to allow the second compressor to deliver refrigerant to the shared equipment.

[0015] In a specific embodiment of the control method for the air conditioning system described above, the control method further includes: acquiring the on / off status of each device; and determining whether to open the corresponding valve based on the on / off status of each device.

[0016] In a specific implementation of the control method for the above-mentioned air conditioning system, "determining whether to open the corresponding valve based on the on / off state of each device" includes: if the device is in the off state, then closing the corresponding valve; and / or, if the device is in the on state, then opening the corresponding valve.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The air conditioning system control method provided by this invention includes: acquiring the actual temperature and preset temperature of all operating equipment; adjusting the opening degree of corresponding valves according to the actual temperature and preset temperature of the equipment; and determining the compressor operating frequency based on the opening degree of all valves. The opening degree of all valves can reflect the refrigerant flow demand of all equipment; the lower the refrigerant flow demand, the lower the power requirement of the compressor. By controlling the compressor operating frequency based on the refrigerant flow demand of all equipment, the compressor operating frequency can be matched to the current state of all equipment and allocated according to the demand of each equipment, so that the refrigerant can be used rationally to improve energy utilization efficiency. Attached Figure Description

[0019] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0020] Figure 1 This is a flowchart of the main steps of the control method for the air conditioning system provided in Embodiment 1 of the present invention;

[0021] Figure 2 This is a flowchart illustrating how the operating frequency of the compressor is determined based on the opening degree of all valves in Embodiment 1 of the present invention.

[0022] Figure 3This is a further flowchart of the control method for the air conditioning system provided in Embodiment 1 of the present invention;

[0023] Figure 4 Piping diagram of the air conditioning system provided in Embodiment 2 of the present invention;

[0024] Figure 5 This is a cross-sectional view of the reversing valve in the first valve position according to Embodiment 2 of the present invention;

[0025] Figure 6 This is a schematic cross-sectional view of the reversing valve in the second valve position according to Embodiment 2 of the present invention;

[0026] Figure 7 This is a flowchart detailing the steps of the control method for the air conditioning system provided in Embodiment 2 of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 11. First compressor; 12. First condenser; 13. First expansion valve; 14. Second evaporator; 15. First delivery pipe; 16. First return pipe; 17. Second valve;

[0029] 21. Second compressor; 22. Second condenser; 23. Second expansion valve; 24. Third evaporator; 25. Second delivery pipe; 26. Second return pipe; 27. Third valve;

[0030] 3. First evaporator; 31. First pipe; 32. Second pipe; 33. First valve; 4. Reversing valve; 41. Valve body; 42. Valve core; 421. First channel; 422. Second channel. Detailed Implementation

[0031] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0032] It should be noted that in the description of this invention, terms such as "upper," "lower," "left," "right," "inner," and "outer," indicating directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through an intermediate medium, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0034] Example 1

[0035] To address the issue of high energy consumption in existing air conditioning systems that use a single compressor to drive multiple devices, this invention provides an air conditioning system.

[0036] Taking an air conditioning system that only performs refrigeration as an example, the air conditioning system provided by this invention includes a compressor, a condenser, an expansion valve, and at least two devices, each of which is equipped with an evaporator. In a specific example of this invention, there are two devices, and the evaporators of the two devices are connected in parallel. The refrigerant flowing out of the compressor outlet flows sequentially through the condenser and the expansion valve, and then enters the two evaporators. The compressor compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The condenser liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant and releases heat to the outside. The liquid refrigerant enters the expansion valve for throttling, and then passes through the two evaporators to absorb heat, causing the liquid refrigerant to evaporate into a gaseous state, which then enters the compressor for compression and pressurization. This cycle repeats continuously, utilizing the heat absorbed by the two evaporators for refrigeration.

[0037] The equipment can be air conditioning indoor units, cold storage, refrigerators, heat pump units, etc. It should be noted that the types of equipment can be the same or different.

[0038] Additionally, it should be noted that although the air conditioning system in this example is used for cooling, this is not a specific limitation of the invention. Without departing from the principles of the invention, the air conditioning system provided by this invention can also be used for heating. Specifically, when the air conditioning system is used for heating, the refrigerant supplied by the compressor flows sequentially through two evaporators, then converges and flows through the expansion valve and condenser, thereby releasing heat at the two evaporators to achieve heating.

[0039] The refrigerant piping within the equipment is equipped with valves that can adjust their opening. Specifically, a first control valve is installed on the inlet or outlet pipe of one evaporator, and a second control valve is installed at the inlet or outlet of the other evaporator. By controlling the opening of the first control valve, the flow rate of refrigerant flowing through the first evaporator can be controlled. By controlling the opening of the second control valve, the flow rate of refrigerant flowing through the second evaporator can be controlled. The greater the flow rate of refrigerant through both evaporators, the better the cooling or heating effect.

[0040] During the refrigerant flow process, the amount of refrigerant distributed to the two evaporators depends not only on the opening degree of the first and second control valves, but also on the cross-section and length of the refrigerant pipes within the equipment. The larger the cross-section and the shorter the length of the refrigerant pipe, the greater the flow rate of refrigerant distributed to the equipment. Let the pipe coefficient of the equipment's refrigerant pipes be K. The pipe coefficient K is positively correlated with the cross-section of the refrigerant pipe and negatively correlated with the length of the refrigerant pipe. The larger the cross-section and the shorter the length of the refrigerant pipe, the larger the pipe coefficient K.

[0041] The pipe coefficient K can be obtained by measuring the pipe resistance. The pipe coefficient K of the equipment with the lowest pipe resistance is taken as a reference and set to 1. The pipe coefficients of other equipment are the ratio of the lowest pipe resistance to the pipe resistance of that equipment.

[0042] The air conditioning system provided in this embodiment of the invention also includes a control module, which is capable of executing the control method of the air conditioning system. For example... Figure 1 As shown, the control method of the air conditioning system mainly includes the following steps:

[0043] S1. Obtain the actual temperature and preset temperature of each device. The preset temperature is the temperature set by the user, i.e., the temperature the device is expected to reach. This preset temperature can be set according to the user's needs.

[0044] S2. Adjust the valve opening for each piece of equipment according to its actual temperature and preset temperature. This includes the following steps:

[0045] S21. Calculate the difference between the actual temperature and the preset temperature of each device.

[0046] S22. Adjust the opening of the corresponding valve based on the difference between the actual temperature and the preset temperature of the equipment. The larger the difference between the actual temperature and the preset temperature, the larger the valve opening, the greater the flow of refrigerant through the equipment, and the better the cooling or heating effect of the equipment. It should be noted that the functional relationship between the difference between the actual temperature and the preset temperature and the valve opening is built into the air conditioning system. This function can be adjusted according to the specific needs of the equipment, ensuring that the difference between the actual temperature and the preset temperature is positively correlated with the valve opening.

[0047] S3. Determine the compressor's operating frequency based on the opening degree of all valves. For example... Figure 2 As shown, step S3 specifically includes the following steps:

[0048] S31. Obtain the pipeline coefficient K for each device.

[0049] S32. Obtain the valve opening degree SZ corresponding to each device.

[0050] S33. Calculate the calculated opening degree of all valves. The calculated opening degree of all valves is the sum of the calculated opening degrees of each valve. The calculated opening degree of each valve is K*SZ, and the calculated opening degree of all valves is... Where x represents the total number of devices connected to the compressor, i.e., the total number of devices through which the refrigerant flows. The lower the calculated opening degree of each valve, the less refrigerant flows through that device, and the closer the actual temperature of that device is to the preset temperature. The sum of the calculated opening degrees of all valves reflects the refrigerant flow requirements of all devices; the lower the refrigerant flow requirement, the lower the power requirement for the compressor. By controlling the refrigerant flow requirements of all devices, the compressor's operating frequency is matched to the current state of all devices and allocated according to the demand of each device, ensuring that the refrigerant is used rationally and improving energy efficiency.

[0051] S34. Adjust the compressor's operating frequency according to the calculated opening degree of all valves. Specifically, if the calculated opening degree of all valves is greater than a first preset opening degree, the compressor operates at a first frequency; if the calculated opening degree of all valves is less than a second preset opening degree, the compressor operates at a third frequency; if the calculated opening degree of all valves is greater than the second preset opening degree and less than the first preset opening degree, the compressor operates at a second frequency. The first and second preset opening degrees gradually decrease, and the first, second, and third frequencies gradually decrease as well.

[0052] It should be noted that although in the example of this invention, when adjusting the operating frequency of the compressor according to the calculated opening degree of all valves, the operating frequency of the compressor is set to three levels, this is not a specific limitation of this invention. Without departing from the principle of this invention, those skilled in the art can set the operating frequency of the compressor to more levels according to the calculated opening degree of all valves, and all of these should be included within the protection scope of this invention.

[0053] Furthermore, such as Figure 3 As shown, the control method of this air conditioning system also includes:

[0054] S0: Obtain the on / off status of each device.

[0055] S01. Determine whether to open the corresponding valve based on the on / off status of each piece of equipment. Specifically, if the equipment is in the off state, close the corresponding valve; if the equipment is in the on state, open the corresponding valve. After the valve is closed, the valve opening degree SZ is zero.

[0056] Steps S0 and S01 are executed before step S1.

[0057] Example 2

[0058] This invention provides an air conditioning system for a vehicle, comprising a first refrigeration system and a second refrigeration system. The first refrigeration system is driven by the engine and starts after the vehicle is started. The second refrigeration system utilizes the vehicle's battery as a power source and can start when the vehicle is parked. The first and second refrigeration systems are structurally similar to the air conditioning system provided in Embodiment 1.

[0059] like Figure 4 As shown, the air conditioning system also includes a reversing valve 4, which is connected to the first and second refrigeration systems via pipes. A portion of the equipment is shared; switching the reversing valve 4 allows the first and second refrigeration systems to supply refrigerant to the shared equipment. When the vehicle starts, the switching valve 4 connects the first refrigeration system to the shared equipment, enabling the shared equipment to operate. When the vehicle is parked, the switching valve 4 connects the second refrigeration system to the shared equipment, enabling the shared equipment to operate. Equipment other than the shared equipment can only be supplied with refrigerant by one of the first or second refrigeration systems.

[0060] Specifically, in the example of this invention, the shared device is a refrigerator, and the other devices are a vehicle air conditioner and a parking air conditioner. The vehicle air conditioner is cooled by a first refrigeration system, and the parking air conditioner is cooled by a second refrigeration system.

[0061] The first refrigeration system includes a first compressor 11, a first condenser 12, a first expansion valve 13, and a second evaporator 14. The first compressor 11, the first condenser 12, the first expansion valve 13, and the second evaporator 14 are connected sequentially through pipes to form a circulation loop. The loop is filled with refrigerant. The first compressor 11 can compress the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The first condenser 12 liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant and releases heat to the outside. The liquid refrigerant enters the first expansion valve 13 for throttling, and then passes through the second evaporator 14 to absorb heat, causing the liquid refrigerant to evaporate into a gaseous state, and then enters the first compressor 11 for compression and pressurization, thus repeating the cycle.

[0062] The first compressor 11 is driven by the vehicle's engine. After the vehicle starts, the engine rotates, driving the first compressor 11 to work and achieve cooling at the second evaporator 14. The second evaporator 14 is installed inside the vehicle's air conditioning system to cool the vehicle.

[0063] The second refrigeration system includes a second compressor 21, a second condenser 22, a second expansion valve 23, and a third evaporator 24. The second compressor 21, the second condenser 22, the second expansion valve 23, and the third evaporator 24 are connected in sequence through pipes to form a circulation loop. The loop is filled with refrigerant. The second compressor 21 can compress the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The second condenser 22 liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant and releases heat to the outside. The liquid refrigerant enters the second expansion valve 23 for throttling, and then passes through the third evaporator 24 to absorb heat, causing the liquid refrigerant to evaporate into a gaseous state, and then enters the second compressor 21 for compression and pressurization, thus repeating the cycle.

[0064] The third evaporator 24 is located within the parking air conditioner and provides cooling for the parking air conditioner. The second compressor 21 is powered by the vehicle's battery. When the vehicle is parked, the vehicle's battery provides energy to the second compressor 21, achieving cooling at the third evaporator 24.

[0065] In addition, the vehicle refrigeration system provided by the present invention also includes a first evaporator 3 and a reversing valve 4. The first evaporator 3 is disposed inside the refrigerator. The inlet and outlet of the first evaporator 3 are respectively connected to a first pipe 31 and a second pipe 32. The outlet of the first expansion valve 13 is connected to a first delivery pipe 15, and the inlet of the first compressor 11 is connected to a first return pipe 16. The outlet of the second expansion valve 23 is connected to a second delivery pipe 25, and the inlet of the second compressor 21 is connected to a second return pipe 26.

[0066] The first delivery pipe 15, the first return pipe 16, the second delivery pipe 25, the second return pipe 26, the first pipe 31, and the second pipe 32 are all connected to the reversing valve 4. The reversing valve 4 can switch between connecting the first pipe 31 to the first delivery pipe 15 and the second pipe 32 to the first return pipe 16, or connecting the first pipe 31 to the second delivery pipe 25 and the second pipe 32 to the second return pipe 26. When the first pipe 31 is connected to the first delivery pipe 15 and the second pipe 32 is connected to the first return pipe 16, the refrigerant flowing from the first expansion valve 13 can enter the first evaporator 3, where the first compressor 11 can perform work to achieve cooling at the first evaporator 3. When the first pipe 31 is connected to the second delivery pipe 25 and the second pipe 32 is connected to the second return pipe 26, the refrigerant flowing from the second expansion valve 23 can enter the first evaporator 3, where the second compressor 21 can perform work to achieve cooling at the first evaporator 3.

[0067] When the vehicle starts, the engine drives the first compressor 11, switching the reversing valve 4 to connect the first evaporator 3 to the first compressor 11. The first compressor 11 then performs work, achieving cooling at the first evaporator 3 and the second evaporator 14, thus enabling the vehicle's air conditioning and refrigerator to cool. When the vehicle is parked, the vehicle's battery drives the second compressor 21, switching the reversing valve 4 to connect the first evaporator 3 to the second compressor 21. The second compressor 21 then performs work, achieving cooling at the first evaporator 3 and the third evaporator 24, thus enabling the parking air conditioning and refrigerator to cool. This ensures that the refrigerator can operate normally both when the vehicle is in motion and when parked.

[0068] Specifically, such as Figure 5 and Figure 6 As shown, the reversing valve 4 includes a valve body 41 and a valve core 42. The valve body 41 has a cavity, and the valve core 42 is located within the cavity and can rotate relative to the valve body 41. The first delivery pipe 15, the first return pipe 16, the second delivery pipe 25, the second return pipe 26, the first pipe 31, and the second pipe 32 are all connected to the valve body 41 and communicate with the cavity. The valve core 42 has a first channel 421 and a second channel 422. As the valve core 42 rotates relative to the valve body 41, it has a first valve position and a second valve position. When the valve core 42 is in the first valve position, the first channel 421 connects the first pipe 31 and the first delivery pipe 15, and the second channel 422 connects the second pipe 32 and the first return pipe 16, so that the first evaporator 3 is connected to the first compressor 11; when the valve core 42 is in the second valve position, the second channel 422 connects the first pipe 31 and the second delivery pipe 25, and the first channel 421 connects the second pipe 32 and the second return pipe 26, so that the first evaporator 3 is connected to the second compressor 21.

[0069] It should be noted that the structure of the reversing valve 4 described in the embodiments of the present invention is not a specific limitation of the present invention. Without departing from the principle of the present invention, in other embodiments, those skilled in the art can also set the reversing valve 4 as a hydraulic valve group for switching, so that the first compressor 11 or the second compressor 21 is connected to the first evaporator 3.

[0070] The inlets of the first evaporator 3, the second evaporator 14, and the third evaporator 24 are respectively equipped with a first valve 33, a second valve 17, and a third valve 27 that can control the opening degree. By controlling the opening degree of the corresponding valves, it is possible to control whether the refrigerant flows through the first evaporator 3, the second evaporator 14, and the third evaporator 24, as well as the flow rate of the refrigerant flowing through the first evaporator 3, the second evaporator 14, and the third evaporator 24.

[0071] In summary, the working principle of the air conditioning system provided by this invention is as follows:

[0072] When the vehicle starts, the reversing valve 4 switches to connect the first evaporator 3 to the first compressor 11. Simultaneously, the engine rotates and drives the first compressor 11. The first compressor 11 compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The first condenser 12 liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant, releasing heat to the outside. The liquid refrigerant enters the first expansion valve 13, where it is throttled. Part of the refrigerant absorbs heat through the second evaporator 14, and the other part absorbs heat through the first evaporator 3, causing the liquid refrigerant to evaporate and form a gaseous state. This gaseous state then re-enters the first compressor 11 for compression and pressurization. This cycle repeats continuously to cool the vehicle's air conditioning and refrigerator.

[0073] When the vehicle is parked, the reversing valve 4 is switched to connect the first evaporator 3 to the second compressor 21. The vehicle's battery provides power to the second compressor 21, which compresses the low-temperature, low-pressure gaseous refrigerant into a high-temperature, high-pressure gaseous refrigerant. The second condenser 22 liquefies the high-temperature, high-pressure gaseous refrigerant into a medium-temperature, medium-pressure liquid refrigerant, releasing heat to the outside. After the liquid refrigerant enters the second expansion valve 23 for throttling, a portion of it passes through the third evaporator 24 to absorb heat, causing the liquid refrigerant to evaporate and form a gaseous state. It then enters the second compressor 21 for compression and pressurization, and this cycle repeats continuously to cool the parking air conditioner and refrigerator.

[0074] like Figure 7 As shown, the air conditioning system control method provided in this embodiment of the invention specifically includes the following steps:

[0075] S1. Obtain the engine speed.

[0076] S2. Determine if the engine speed is lower than the preset value. If the engine speed is lower than the preset value, proceed to step S3; if the engine speed is not lower than the preset value, proceed to step S4.

[0077] S3. Start the second compressor 21 and switch the reversing valve 4 to connect the first evaporator 3 with the second compressor 21. At this time, the second compressor 21 does work, and the refrigerant flows through the first evaporator 3 and the third evaporator 24 to cool the refrigerator and the parking air conditioner.

[0078] S4. Start the first compressor 11 and switch the reversing valve 4 to connect the first evaporator 3 with the first compressor 11. At this time, the first compressor 11 does work, and the refrigerant flows through the first evaporator 3 and the second evaporator 14 to cool the refrigerator and the vehicle air conditioner.

[0079] S5. Obtain the on / off status of the refrigerator, vehicle air conditioner and parking air conditioner, and execute steps S6 and S7.

[0080] S6. Determine if the refrigerator is open. If the refrigerator is open, open the first valve 33 and execute step S8; if the refrigerator is closed, close the first valve 33, i.e., the opening degree is zero.

[0081] S7. Determine whether the vehicle air conditioner or parking air conditioner is on. If the vehicle air conditioner or parking air conditioner is on, open the second valve 17 or the third valve 27 and execute step S9; if the vehicle air conditioner or parking air conditioner is off, close the second valve 17 or the third valve 27, i.e., the opening degree is zero.

[0082] S8. Obtain the actual temperature inside the refrigerator and the preset temperature of the refrigerator.

[0083] S81. Obtain the opening degree of the first valve 33 based on the difference between the actual temperature inside the refrigerator and the preset temperature of the refrigerator.

[0084] S9. Obtain the actual temperature inside the vehicle cabin and the preset temperature inside the vehicle cabin.

[0085] S10. Obtain the opening degree of the second valve 17 or the third valve 27 based on the difference between the actual temperature inside the cabin and the preset temperature inside the cabin.

[0086] S11. Calculate the calculated opening degree of all valves. Specifically, when the engine is started, the calculated opening degree of all valves is equal to the sum of the calculated opening degrees of the first valve 33 and the second valve 17; when the vehicle is parked, the calculated opening degree of all valves is equal to the sum of the calculated opening degrees of the first valve 33 and the third valve 27.

[0087] S12. Determine whether the calculated opening degree of all valves is greater than the first preset opening degree. If the calculated opening degree of all valves is greater than the first preset opening degree, proceed to step S13; if the calculated opening degree of all valves is not greater than the first preset opening degree, proceed to step S14.

[0088] S13. The compressor operates at the first frequency. When the engine is started, the compressor is the first compressor; when the vehicle is parked, the compressor is the second compressor.

[0089] S14. Determine whether the calculated opening degree of all valves is less than the second preset opening degree. If the calculated opening degree of all valves is less than the second preset opening degree, proceed to step S15; if the calculated opening degree of all valves is not less than the second preset opening degree, proceed to step S16.

[0090] S15. The compressor operates at a third frequency. When the engine is started, the compressor is the first compressor; when the vehicle is parked, the compressor is the second compressor.

[0091] S16. The compressor operates at a second frequency. When the engine is started, the compressor is the first compressor; when the vehicle is parked, the compressor is the second compressor.

[0092] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A control method for an air conditioning system, characterized in that, The air conditioning system includes a compressor and at least two devices. The compressor can deliver refrigerant to the devices through refrigerant pipelines for cooling or heating. Each of the refrigerant pipelines in the devices is equipped with a valve that can adjust the opening degree. The control method for the air conditioning system includes: Obtain the actual temperature and preset temperature of all operating devices; Adjust the opening degree of the corresponding valve according to the actual temperature and preset temperature of the equipment; The operating frequency of the compressor is determined based on the opening degree of all the valves. The phrase "determining the operating frequency of the compressor based on the opening degree of all the valves" includes: Obtain the pipe coefficient K for each device. The pipe coefficient K is positively correlated with the cross-section of the refrigerant pipe in the device and negatively correlated with the length of the refrigerant pipe. The pipe coefficient K is obtained by measuring the pipe resistance. The pipe coefficient K of the device with the smallest pipe resistance is taken as a reference and set to 1. The pipe coefficients of the other devices are the ratio of the smallest pipe resistance to the pipe resistance of the device. Obtain the valve opening degree SZ corresponding to each device; Calculate and obtain the calculated opening degree of all the valves. The calculated opening degree of all the valves is: Where x is the total number of devices connected to the compressor; The operating frequency of the compressor is adjusted according to the calculated opening degree of all the valves.

2. The control method for the air conditioning system according to claim 1, characterized in that, "Adjusting the opening degree of the corresponding valve according to the actual temperature and preset temperature of the equipment" includes: Calculate the difference between the actual temperature and the preset temperature for each of the devices; The opening degree of the corresponding valve is adjusted according to the difference between the actual temperature and the preset temperature of the device.

3. The control method for the air conditioning system according to claim 1, characterized in that, "Adjusting the operating frequency of the compressor based on the calculated opening degree of all the valves" includes: If the calculated opening degree of all the valves is greater than the first preset opening degree, the compressor operates at the first frequency.

4. The control method for an air conditioning system according to claim 1, characterized in that, "Adjusting the operating frequency of the compressor based on the calculated opening degree of all the valves" also includes: If the calculated opening degree of all the valves is less than the second preset opening degree, the compressor operates at the third frequency.

5. The control method for an air conditioning system according to claim 1, characterized in that, "Adjusting the operating frequency of the compressor based on the calculated opening degree of all the valves" also includes: If the calculated opening degree of all the valves is greater than the second preset opening degree and less than the first preset opening degree, then the compressor operates at the second frequency.

6. The control method for an air conditioning system according to claim 1, characterized in that, The air conditioning system is applied to a vehicle, and the compressor includes a first compressor and a second compressor. The first compressor is driven by the vehicle's engine, and the second compressor is driven by the vehicle's battery. The air conditioning system also includes a reversing valve, which is connected to the first compressor and the second compressor via a pipeline. At least one of the devices is a shared device. Switching the reversing valve can enable the first compressor or the second compressor to deliver refrigerant to the shared device. The control method for the air conditioning system further includes: Obtain the engine speed; The first compressor or the second compressor is controlled to operate according to the engine speed, and the reversing valve is switched so that one of the first compressor and the second compressor is in the operating state to deliver refrigerant to the common equipment.

7. The control method for an air conditioning system according to claim 6, characterized in that, "Controlling the operation of the first compressor or the second compressor according to the engine speed, and switching the reversing valve to supply refrigerant to the shared equipment in one of the operating states of the first compressor and the second compressor" includes: If the engine speed is not lower than a preset value, the first compressor is started, and the reversing valve is switched so that the first compressor supplies refrigerant to the shared equipment; and / or If the engine speed is lower than the preset value, the second compressor is started and the reversing valve is switched so that the second compressor delivers refrigerant to the shared equipment.

8. The control method for an air conditioning system according to claim 1, characterized in that, The control method for the air conditioning system further includes: Obtain the on / off status of each of the aforementioned devices; Whether to open the corresponding valve is determined based on the opening and closing status of each device.

9. The control method for an air conditioning system according to claim 8, characterized in that, "Determining whether to open the corresponding valve based on the opening / closing status of each device" includes: If the device is in the off state, then close the corresponding valve; and / or, If the device is in the on state, then the corresponding valve is opened.

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