Heating control method and system of air-cooled multi-split system and storage medium

Abstract

The application provides a heating control method and system of an air-cooled multi-connected system and a storage medium. The heating control method of the air-cooled multi-connected system comprises the following steps: detecting an operating parameter of the air-cooled multi-connected system; determining whether the operating parameter meets a first preset condition; and if yes, controlling a pipeline switching device to switch to a first state, so that the refrigerant in a gas-liquid mixed state flowing out of an indoor heat exchanger flows into a subcooling pipe, heat exchange is performed on the refrigerant by the subcooling pipe, and the gaseous refrigerant is further liquefied. The scheme can improve the refrigerant circulation amount of the system, especially the refrigerant circulation amount under low-temperature heating, and effectively improve the overall energy efficiency of the system.

Description

Technical Field

[0001] This invention relates to the field of home appliance technology, and in particular to a heating control method, system, and storage medium for an air-cooled multi-split air conditioning system. Background Technology

[0002] With social development and the continuous improvement of people's living standards, various air conditioning devices have become one of the indispensable electrical appliances in people's daily lives. These devices help people achieve a comfortable temperature and humidity level when the ambient temperature and humidity are too high or too low. Currently, air conditioning devices mainly include various types of air conditioners and fans.

[0003] The air-cooled multi-split air conditioning system consists of one outdoor unit and multiple indoor units connected in parallel. When operating in cooling mode, the outdoor heat exchanger acts as the system's condenser, and the indoor heat exchangers act as the system's evaporators. Cooling is provided to the indoor environment through the supply and return air circulation of the indoor units, lowering the indoor temperature and making users feel cool. When operating in heating mode, the outdoor heat exchanger acts as the system's evaporator, and the indoor heat exchangers act as the system's condenser. Heat is provided to the indoor environment through the supply and return air circulation of the indoor units, raising the indoor temperature and making users feel warm.

[0004] Air-cooled multi-split air conditioning systems can be controlled independently in multiple rooms and offer flexible interoperability, leading to their increasingly widespread application. However, current air-cooled multi-split systems suffer from the following problems: insufficient refrigerant during operation can result in poor cooling and heating performance. This is especially true for low-temperature heating, where limited outdoor evaporation conditions cause most of the refrigerant to accumulate at the bottom of the gas-liquid separator, resulting in insufficient overall refrigerant circulation and consequently, poor overall heating performance.

[0005] To increase refrigerant circulation in low-temperature heating conditions, current air-cooled multi-split systems generally employ either vapor injection enthalpy-enhancing compressors or heating elements added to the bottom of the gas-liquid separator. However, using vapor injection enthalpy-enhancing compressors significantly increases operating and maintenance costs, consumes substantial amounts of energy, and generates considerable noise, which not only affects the health of operators but also causes noise pollution. While adding heating elements to the bottom of the gas-liquid separator can increase the temperature of the liquid refrigerant and thus increase the overall refrigerant circulation volume, it also increases electricity consumption, resulting in energy waste. Summary of the Invention

[0006] One objective of this invention is to increase the refrigerant circulation volume under low-temperature heating conditions, thereby improving the overall energy efficiency of the system.

[0007] A further objective of this invention is to utilize the heat that would otherwise be dissipated to preheat the bottom of the gas-liquid separator, thereby effectively saving energy and reducing operating costs.

[0008] Specifically, the present invention provides a heating control method for an air-cooled multi-split air conditioning system, wherein the air-cooled multi-split air conditioning system includes: an indoor heat exchanger, a subcooling pipe, and a pipe switching device, and the method includes: detecting the operating parameters of the air-cooled multi-split air conditioning system; determining whether the operating parameters meet a first preset condition; and if so, controlling the pipe switching device to switch to a first state, so that the refrigerant in a gas-liquid mixed state flowing out of the indoor heat exchanger flows into the subcooling pipe, and the subcooling pipe is used to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied.

[0009] Optionally, the steps for detecting the operating parameters of the air-cooled multi-split air conditioning system include: detecting the outdoor ambient temperature, the low pressure at the compressor's suction port, the exhaust temperature, and the temperature of the indoor unit's air intake pipe and liquid inlet pipe.

[0010] Optionally, the step of determining whether the operating parameters meet the first preset conditions includes: determining whether the outdoor ambient temperature is lower than the first preset temperature, whether the low pressure at the compressor's suction port is lower than the first preset pressure and the duration is greater than the first preset duration, whether the exhaust temperature is greater than or equal to the second preset temperature, and whether the difference between the intake pipe temperature and the liquid inlet pipe temperature is greater than or equal to the third preset temperature.

[0011] Optionally, the indoor heat exchanger is configured to condense and liquefy the gaseous refrigerant to release heat; and the air-cooled multi-split system further includes: an outdoor heat exchanger configured to vaporize the liquid refrigerant to absorb heat from the outdoor environment; and a gas-liquid separator connected to the outdoor heat exchanger, configured to separate the refrigerant flowing out of the outdoor heat exchanger into gas and liquid components, with a subcooling pipe located at the bottom of the gas-liquid separator.

[0012] Optionally, the air-cooled multi-split system also includes: an indoor throttling device connected to the indoor heat exchanger, configured to regulate the refrigerant flow and be fully open, wherein when the pipe switching device is switched to the first state, the gas-liquid mixed refrigerant flowing out of the indoor heat exchanger flows through the indoor throttling device and then into the subcooling pipe; and an outdoor throttling device connected to the outdoor heat exchanger, configured to regulate the refrigerant flow and be partially open, wherein when the pipe switching device is switched to the first state, the refrigerant that has undergone heat exchange through the subcooling pipe flows through the outdoor throttling device and then into the outdoor heat exchanger.

[0013] Optionally, before the step of detecting the operating parameters of the air-cooled multi-split system, the method further includes: receiving a trigger signal for the air-cooled multi-split system to start the heating mode; controlling the pipeline switching device to switch to the second state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger flows through the indoor throttling device and then into the outdoor throttling device; and controlling the air-cooled multi-split system to complete a defrosting process.

[0014] Optionally, if the operating parameters do not meet the first preset condition, the control pipeline switching device remains in the second state.

[0015] Optionally, after the step of switching the control pipeline switching device to the first state, the method further includes: determining whether the operating parameters meet the second preset condition; and if so, executing the step of switching the control pipeline switching device to the second state; if not, the control pipeline switching device remains in the first state.

[0016] Optionally, the step of determining whether the operating parameters meet the second preset conditions includes: determining whether the outdoor ambient temperature is greater than or equal to the fourth preset temperature, the low pressure is greater than the second preset pressure and the duration is greater than the second preset duration, and the difference between the air inlet pipe temperature and the liquid inlet pipe temperature is less than or equal to the fifth preset temperature.

[0017] Optionally, the pipeline switching device includes: a first solenoid valve and a second solenoid valve, wherein the first solenoid valve is disposed between the subcooling pipe and the outdoor throttling device, and the second solenoid valve is disposed between the indoor throttling device and the outdoor throttling device.

[0018] Optionally, the step of controlling the pipeline switching device to switch to the first state includes: controlling the first solenoid valve to open and the second solenoid valve to close; the step of controlling the pipeline switching device to switch to the second state includes: controlling the first solenoid valve to close and the second solenoid valve to open.

[0019] According to another aspect of the present invention, an air conditioner is also provided, comprising: a controller, the controller including a memory and a processor, wherein the memory stores a machine-executable program, which, when executed by the processor, implements the control method of the air conditioner described above.

[0020] According to another aspect of the present invention, a machine-readable storage medium is also provided, on which a machine-executable program is stored, which, when executed by a processor, implements the control method of the air conditioner described above.

[0021] The heating control method, system, and storage medium of the air-cooled multi-split air conditioning system of the present invention detect the operating parameters of the air-cooled multi-split air conditioning system; determine whether the operating parameters meet a first preset condition; and if so, control the pipeline switching device to switch to a first state so that the refrigerant in a gas-liquid mixed state flowing out of the indoor heat exchanger flows into the subcooling pipe, and uses the subcooling pipe to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied, which can increase the refrigerant circulation volume of the system, especially the refrigerant circulation volume under low temperature heating conditions, and effectively improve the overall energy efficiency of the system.

[0022] Furthermore, the heating control method, system, and storage medium of the air-cooled multi-split air conditioning system of the present invention receive a trigger signal for the air-cooled multi-split air conditioning system to activate the heating mode; control the pipeline switching device to switch to a second state, so that the refrigerant in a gas-liquid mixture flowing from the indoor heat exchanger flows through the indoor throttling device and then into the outdoor throttling device; control the air-cooled multi-split air conditioning system to complete a defrosting process, and when the operating parameters of the air-cooled multi-split air conditioning system meet the first preset condition, control the pipeline switching device to switch to the first state, so that the refrigerant in a gas-liquid mixture flowing from the indoor heat exchanger flows into the subcooling pipe, and uses the subcooling pipe to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied; when the operating parameters meet the second preset condition, control the pipeline switching device to switch to the second state; adjust the pipeline switching device according to the actual situation to make the refrigerant flow path reasonable, increase the refrigerant circulation volume of the system, and use the heat that should have been dissipated to preheat the bottom of the gas-liquid separator, effectively saving energy, avoiding additional replacement or addition of equipment or consumption of electricity, and greatly reducing operating costs.

[0023] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0024] The following sections will describe some specific embodiments of the invention in detail by way of example and not limitation, with reference to the accompanying drawings. The same reference numerals in the drawings denote the same or similar parts or portions. Those skilled in the art should understand that these drawings are not necessarily drawn to scale. In the drawings:

[0025] Figure 1 This is a connection diagram of an air-cooled multi-split air conditioning system according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a heating control method for an air-cooled multi-split air conditioning system according to an embodiment of the present invention;

[0027] Figure 3 This is a detailed flowchart of a heating control method for an air-cooled multi-split air conditioning system according to an embodiment of the present invention;

[0028] Figure 4 This is a schematic block diagram of the controller of an air-cooled multi-split air conditioning system according to an embodiment of the present invention; and

[0029] Figure 5 This is a schematic diagram of a machine-readable storage medium according to an embodiment of the present invention. Detailed Implementation

[0030] Figure 1 This is a connection diagram of an air-cooled multi-split air conditioning system 100 according to an embodiment of the present invention. Figure 1 As shown, the air-cooled multi-split air conditioning system 100 of this embodiment generally includes: an indoor heat exchanger 106, a subcooling pipe 113, and a pipe switching device. When the air-cooled multi-split air conditioning system 100 is operating in heating mode, the indoor heat exchanger 106 can be configured to condense and liquefy the gaseous refrigerant to release heat. The pipe switching device can be configured to switch to a first state when the operating parameters of the air-cooled multi-split air conditioning system 100 meet a first preset condition, so that the gas-liquid mixed refrigerant flowing from the indoor heat exchanger 106 flows into the subcooling pipe 113. The subcooling pipe 113 can be configured to exchange heat with the gas-liquid mixed refrigerant flowing from the indoor heat exchanger 106, so that the gaseous refrigerant is further liquefied.

[0031] In one specific embodiment, such as Figure 1 As shown, the air-cooled multi-split air conditioning system 100 may further include an outdoor heat exchanger 112 and a gas-liquid separator 117. The outdoor heat exchanger 112 can be configured to vaporize liquid refrigerant to absorb heat from the outdoor environment. The gas-liquid separator 117 can be connected to the outdoor heat exchanger 112 and configured to separate the refrigerant flowing out of the outdoor heat exchanger 112 into gas and liquid components. Furthermore, a subcooling pipe 113 is located at the bottom of the gas-liquid separator 117. The subcooling pipe 113's location at the bottom of the gas-liquid separator 117 allows the refrigerant, after further liquefaction via the subcooling pipe 113, to flow into the outdoor heat exchanger 112 as quickly as possible, preventing premature evaporation and thus avoiding impact on the overall refrigerant circulation volume.

[0032] As mentioned earlier, current air-cooled multi-split air conditioning systems have the following problems: insufficient refrigerant during operation will result in poor cooling and heating performance. Especially in low-temperature heating situations, limited outdoor evaporation conditions cause most of the refrigerant to accumulate at the bottom of the gas-liquid separator, resulting in insufficient overall refrigerant circulation and poor overall heating performance.

[0033] To increase refrigerant circulation in low-temperature heating conditions, current air-cooled multi-split systems generally employ either vapor injection enthalpy-enhancing compressors or heating elements added to the bottom of the gas-liquid separator. However, using vapor injection enthalpy-enhancing compressors significantly increases operating and maintenance costs, consumes substantial amounts of energy, and generates considerable noise, which not only affects the health of operators but also causes noise pollution. While adding heating elements to the bottom of the gas-liquid separator can increase the temperature of the liquid refrigerant and thus increase the overall refrigerant circulation volume, it also increases electricity consumption, resulting in energy waste.

[0034] The air-cooled multi-split air conditioning system 100 of this embodiment can increase the refrigerant circulation volume of the system by setting a subcooling pipe 113 at the bottom of the gas-liquid separator 117, especially the refrigerant circulation volume under low-temperature heating conditions. Furthermore, it can utilize the heat that would otherwise be dissipated to preheat the bottom of the gas-liquid separator 117, effectively saving energy, avoiding the need for additional equipment replacement or addition, or consuming electrical energy, and greatly reducing operating costs.

[0035] like Figure 1 As shown, the air-cooled multi-split system 100 may further include: an indoor throttling device 107 connected to the indoor heat exchanger 106, configured to regulate the refrigerant flow and be fully open. Furthermore, when the pipeline switching device is switched to the first state, the gas-liquid mixed refrigerant flowing from the indoor heat exchanger 106 flows through the indoor throttling device 107 and then into the subcooling pipe 113.

[0036] The air-cooled multi-split system 100 may further include: an outdoor throttling device 114 connected to an outdoor heat exchanger 112, configured to regulate the refrigerant flow and be partially open. Furthermore, when the piping switching device is switched to the first state, the refrigerant that has undergone heat exchange through the subcooling pipe 113 flows through the outdoor throttling device 114 and then into the outdoor heat exchanger 112.

[0037] In other words, when the air-cooled multi-split system 100 is operating in heating mode, the indoor throttling device 107 is fully open, and the outdoor throttling device 114 is partially open. When the air-cooled multi-split system 100 is operating in cooling mode, the opposite is true: the indoor throttling device 107 is partially open, and the outdoor throttling device 114 is fully open. Both the indoor throttling device 107 and the outdoor throttling device 114 can reduce pressure and reduce airflow.

[0038] In a preferred embodiment, both the indoor throttling device 107 and the outdoor throttling device 114 are electronic expansion valves. As an electronic regulating valve, the electronic expansion valve achieves throttling and pressure reduction by controlling the refrigerant flow rate. The working principle of the electronic expansion valve is to control the solenoid valve switch with an electronic signal, thereby changing the orifice size of the expansion valve and thus regulating the refrigerant flow rate.

[0039] By controlling the refrigerant flow through an electronic expansion valve, air-cooled multi-split air conditioning systems can operate more efficiently. Compared to traditional mechanical expansion valves, electronic expansion valves offer higher precision in controlling refrigerant flow, faster response times, and greater energy savings due to their ability to achieve finer flow control and thus higher energy efficiency.

[0040] In one specific embodiment, the pipeline switching device can also be configured to switch to a second state when the operating parameters of the air-cooled multi-split system 100 do not meet the first preset condition, so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows through the indoor throttling device 107 and then into the outdoor throttling device 114.

[0041] like Figure 1 As shown, the pipeline switching device may include a first solenoid valve 110 and a second solenoid valve 119. The first solenoid valve 110 is located between the subcooling pipe 113 and the outdoor throttling device 114, and the second solenoid valve 119 is located between the indoor throttling device 107 and the outdoor throttling device 114. The pipeline switching device may also be configured such that: when switching to the first state, the first solenoid valve 110 is open and the second solenoid valve 119 is closed; when switching to the second state, the first solenoid valve 110 is closed and the second solenoid valve 119 is open. When a solenoid valve is open, the corresponding pipeline is connected; when a solenoid valve is closed, the corresponding pipeline is disconnected. The opening and closing states of the first solenoid valve 110 and the second solenoid valve 119 work together to ensure that the refrigerant flow path differs depending on whether the pipeline switching device is in the first or second state.

[0042] like Figure 1 As shown, the air-cooled multi-split air conditioning system 100 may further include a compressor 101 and an oil separator 103. The compressor 101 may be configured to pressurize the refrigerant gas, making it a high-temperature, high-pressure gas. In a preferred embodiment, the compressor 101 may be a variable frequency compressor. Compared to a compressor with a constant speed, a variable frequency compressor can continuously adjust its speed within a certain range through specific control methods, thereby continuously changing its output energy.

[0043] Variable frequency compressors have the following advantages: Compared with traditional constant frequency compressors, variable frequency compressors consume less energy because they can automatically adjust the compression ratio according to the actual needs of the air compressor to achieve higher efficiency, thereby reducing the energy consumption of the entire system and ultimately achieving the goal of energy conservation and emission reduction; variable frequency compressors are also more efficient because their motor drive can automatically adjust the speed according to actual needs to ensure that optimal efficiency can be maintained under different workloads.

[0044] Furthermore, since variable frequency compressors can automatically adjust their speed, they ensure that the machine can operate at its best under different workloads, thus extending the compressor's lifespan. In addition, because variable frequency compressors generally operate at lower speeds, they can also reduce machine wear and failure rates, improving equipment reliability. Traditional compressors generate significant noise during operation, while variable frequency compressors can reduce noise by automatically controlling their speed, improving the working environment and increasing work efficiency.

[0045] The oil separator 103 can be configured to separate lubricating oil from the refrigerant in the high-temperature, high-pressure gas discharged from the compressor 101. Generally, the oil separator 103 can separate oil particles in the high-pressure vapor under gravity by reducing the airflow velocity and changing the airflow direction. The oil separator 103 separates lubricating oil from the refrigerant, ensuring the safe and efficient operation of the system.

[0046] like Figure 1 As shown, the air-cooled multi-split system 100 may further include: a gas line shut-off valve 108, a liquid line shut-off valve 105, and a four-way valve 104. The gas line shut-off valve 108 can be connected to the indoor heat exchanger 106. The liquid line shut-off valve 105 can be connected to the indoor throttling device 107. The four-way valve 104 can be configured to controllably connect the oil separator 103 and the gas line shut-off valve 108, or connect the outdoor heat exchanger 112 and the gas-liquid separator 117. Specifically, when refrigerant flows out of the compressor 101, the four-way valve 104 can connect the oil separator 103 and the gas line shut-off valve 108. When the refrigerant needs to flow back to the compressor 101, the four-way valve 104 can connect the outdoor heat exchanger 112 and the gas-liquid separator 117.

[0047] Regardless of whether the pipeline switching device is in the first or second state, when the refrigerant finally flows back to the compressor 101, it first passes through the gas-liquid separator 117. Gas-liquid separation is performed by the gas-liquid separator 117, and the gaseous refrigerant flows into the compressor 101. The gas-liquid separator 117 can be considered a device that protects the compressor 101 in the suction process. It can separate the refrigerant into gas and liquid components, preventing the low-pressure, low-temperature wet vapor returning to the compressor 101 from carrying excessive liquid droplets, thus avoiding liquid refrigerant entering the compressor 101 and causing liquid slugging.

[0048] In addition, such as Figure 1 As shown, the air-cooled multi-split air conditioning system 100 can also be equipped with other small components, such as a high-pressure sensor 102, a return air temperature sensor 109, and pipe temperature sensors 116, 120, and 121, which can be configured to detect the pressure and temperature at their respective locations. Additionally, Figure 1 The diagram also shows a return pipe 111, which allows the refrigerant gas to return to the compressor 101 after flowing through the gas-liquid separator 117.

[0049] This embodiment provides a heating control method for an air-cooled multi-split air conditioning system, which can increase the refrigerant circulation volume of the system, especially the refrigerant circulation volume under low-temperature heating conditions, and effectively improve the overall energy efficiency of the system. Figure 2 This is a schematic diagram of a heating control method for an air-cooled multi-split air conditioning system according to an embodiment of the present invention. Figure 2 As shown, the heating control method of this air-cooled multi-split air conditioning system may include the following steps:

[0050] Step S202: Detect the operating parameters of the air-cooled multi-split air conditioning system 100;

[0051] Step S204: Determine whether the running parameters meet the first preset condition. If yes, proceed to step S206.

[0052] In step S206, the control pipeline switching device is switched to the first state so that the refrigerant in a gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows into the subcooling pipe 113, and the subcooling pipe 113 is used to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied.

[0053] It should be noted that the air-cooled multi-split system 100 in the heating control method of the air-cooled multi-split system of this embodiment includes: an indoor heat exchanger 106, a subcooling pipe 113, and a pipe switching device. Specifically, the heating control method of the air-cooled multi-split system of this embodiment can be applied to the aforementioned embodiments. Figure 1 The air-cooled multi-split air conditioning system 100. Furthermore, since this embodiment is a heating control method for an air-cooled multi-split air conditioning system, the above steps are performed when the air-cooled multi-split air conditioning system 100 is operating in heating mode.

[0054] In the above steps, step S202 detects the operating parameters of the air-cooled multi-split air conditioning system 100. Specifically, it can detect the outdoor ambient temperature, the low-pressure at the suction port of the compressor 101, the exhaust temperature, and the intake pipe temperature and liquid inlet pipe temperature of the indoor unit. Step S204 determines whether the operating parameters meet the first preset conditions. Specifically, it can determine whether the outdoor ambient temperature is lower than the first preset temperature, whether the low-pressure at the suction port of the compressor 101 is lower than the first preset pressure and the duration is greater than the first preset duration, whether the exhaust temperature is greater than or equal to the second preset temperature, and whether the difference between the intake pipe temperature and the liquid inlet pipe temperature is greater than or equal to the third preset temperature.

[0055] Then, if the judgment result in step S204 is that the outdoor ambient temperature is less than the first preset temperature, the low pressure at the suction port of compressor 101 is less than the first preset pressure and the duration is greater than the first preset duration, the exhaust temperature is greater than or equal to the second preset temperature, and the difference between the temperature of the intake pipe and the temperature of the liquid inlet pipe is greater than or equal to the third preset temperature, then step S206 can be executed to control the pipeline switching device to switch to the first state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows into the subcooling pipe 113, and the subcooling pipe 113 is used to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied.

[0056] In other words, when the air-cooled multi-split system 100 is operating in heating mode, the indoor heat exchanger 106, acting as the system's condenser, can condense and liquefy the gaseous refrigerant to release heat, raising the indoor temperature and making users feel warm. However, the condensation and liquefaction of the refrigerant by the indoor heat exchanger 106 may not be sufficient, and the refrigerant flowing out of the indoor heat exchanger 106 may be in a gas-liquid mixed state.

[0057] If the operating parameters of the air-cooled multi-split air conditioning system 100 meet the first preset condition, it can be switched to the first state via a pipeline switching device. This allows the gas-liquid mixture of refrigerant flowing from the indoor heat exchanger 106 to flow into the subcooling pipe 113. The subcooling pipe 113 exchanges heat with the gas-liquid mixture of refrigerant flowing from the indoor heat exchanger 106, further liquefying the gaseous refrigerant and allowing it to flow to the next component in a larger liquid state. This increases the refrigerant circulation volume of the system, effectively improving the overall energy efficiency. The first preset condition can be a low-temperature heating condition; that is, the heating control method of the air-cooled multi-split air conditioning system in this embodiment can particularly improve the refrigerant circulation volume under low-temperature heating conditions.

[0058] In summary, the heating control method of the air-cooled multi-split air conditioning system in this embodiment detects the operating parameters of the air-cooled multi-split air conditioning system 100; determines whether the operating parameters meet the first preset condition; and if so, controls the pipeline switching device to switch to the first state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows into the subcooling pipe 113, and uses the subcooling pipe 113 to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied, which can improve the refrigerant circulation volume of the system, especially the refrigerant circulation volume under low temperature heating conditions, and effectively improve the overall energy efficiency of the system.

[0059] In some optional embodiments, the air-cooled multi-split air conditioning system 100 can achieve higher technical effects through further optimization and configuration of the above steps. The following describes in detail the heating control method of the air-cooled multi-split air conditioning system of this embodiment with reference to an optional execution flow of this embodiment. This embodiment is only an example of the execution flow. In specific implementation, the execution order and operating conditions of some steps can be modified according to specific implementation requirements. Figure 3 This is a detailed flowchart of a heating control method for an air-cooled multi-split air conditioning system according to an embodiment of the present invention. The heating control method for the air-cooled multi-split air conditioning system includes the following steps:

[0060] Step S302: Receive the trigger signal for the air-cooled multi-split system 100 to start the heating mode;

[0061] Step S304: The control pipeline switching device is switched to the second state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows through the indoor throttling device 107 and then flows into the outdoor throttling device 114.

[0062] Step S306: Control the air-cooled multi-split system 100 to complete one defrosting process;

[0063] Step S308: Detect the operating parameters of the air-cooled multi-split air conditioning system 100;

[0064] Step S310: Determine whether Tao < T1, Ps < P1 and t > t1, Td ≥ T2, and TC1 - TC2 ≥ T3. If yes, proceed to step S314; otherwise, proceed to step S312.

[0065] Step S312: The control pipeline switching device remains in the second state;

[0066] Step S314: The control pipeline switching device is switched to the first state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows into the subcooling pipe 113, and the subcooling pipe 113 is used to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied.

[0067] Step S316: Determine whether Tao≥T4, Ps>P2 and t>t2, and TC1-TC2≤T5. If yes, proceed to step S304; otherwise, proceed to step S318.

[0068] Step S318: The control pipeline switching device remains in the first state.

[0069] Similarly, the heating control method of the air-cooled multi-split air conditioning system of this embodiment can also be applied to the aforementioned embodiments. Figure 1The air-cooled multi-split air conditioning system 100. In the above steps, step S302 receives a trigger signal for the air-cooled multi-split air conditioning system 100 to start the heating mode, that is, the above steps in this embodiment are performed when the air-cooled multi-split air conditioning system 100 is running in the heating mode.

[0070] After receiving the trigger signal for the air-cooled multi-split system 100 to activate heating mode in step S302, step S304 can be executed to switch the control pipeline switching device to the second state, so that the refrigerant in a gas-liquid mixture flowing from the indoor heat exchanger 106 flows through the indoor throttling device 107 and then into the outdoor throttling device 114. In other words, after receiving the trigger signal, the air-cooled multi-split system 100 can be controlled according to normal heating conditions. The refrigerant flow path when the control pipeline switching device is switched to the second state is suitable for normal heating conditions, without needing to additionally increase the system's refrigerant circulation volume.

[0071] Furthermore, step S306 must be executed first to control the air-cooled multi-split system 100 to complete a defrosting process before proceeding with subsequent steps to further determine whether the state of the pipeline switching device needs to be switched. This ensures that the air-cooled multi-split system 100 has been operating in normal heating mode for a period of time, resulting in a relatively stable state. After defrosting, it is also more conducive to improving heat exchange efficiency and reducing the burden on the compressor 101. Especially when heating at low temperatures, if the pipeline switching device is switched to the first state, it is even more necessary to reduce the burden on the compressor 101 to avoid damage to the compressor 101 and extend its service life.

[0072] Specifically, after defrosting, step S308 can be executed first to detect the operating parameters of the air-cooled multi-split system 100. These operating parameters may include: the outdoor ambient temperature Tao of the air-cooled multi-split system 100, the low-pressure Ps at the suction port of the compressor 101, the exhaust temperature Td, and the indoor unit's intake pipe temperature TC1 and liquid inlet pipe temperature TC2. These operating parameters can be detected after the air-cooled multi-split system 100 has been operating normally in heating mode for a certain period of time. For example, the average of the data at the 10th and 15th minutes can be used to ensure that the detected operating parameters are relatively accurate and reflect the actual situation of the air-cooled multi-split system 100.

[0073] Then, step S310 is executed to determine whether Tao < T1, Ps < P1 and t > t1, Td ≥ T2, and TC1 - TC2 ≥ T3. If the result of step S310 is negative, step S312 is executed to keep the control pipeline switching device in the second state. In fact, the first preset conditions are: the outdoor ambient temperature Tao is less than the first preset temperature T1, the low pressure Ps at the suction port of compressor 101 is less than the first preset pressure P1 and the duration t is greater than the first preset duration t1, the exhaust temperature Td is greater than or equal to the second preset temperature T2, and the difference between the intake pipe temperature TC1 and the liquid inlet pipe temperature TC2 is greater than or equal to the third preset temperature T3.

[0074] Step S310 determines whether the operating parameters meet the first preset condition. As mentioned earlier, the first preset condition can be a condition suitable for low-temperature heating. Therefore, if the operating parameters of the air-cooled multi-split system 100 do not meet the first preset condition, it can be considered as a normal heating condition, rather than a low-temperature heating condition. Under normal heating conditions, step S312 is executed, and the control pipeline switching device remains in the second state. That is, the refrigerant in a gas-liquid mixed state flowing from the indoor heat exchanger 106 continues to flow through the indoor throttling device 107 and then into the outdoor throttling device 114.

[0075] If the result of step S310 is yes, that is, if the operating parameters meet the first preset condition, then step S314 is executed to control the pipeline switching device to switch to the first state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger 106 flows into the subcooling pipe 113, and the subcooling pipe 113 is used to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied.

[0076] Specifically, if the operating parameters meet the first preset condition, it indicates that under low-temperature heating conditions, the refrigerant in a gas-liquid mixture flowing from the indoor heat exchanger 106 flows through the indoor throttling device 107 and then into the subcooling pipe 113. After heat exchange in the subcooling pipe 113, the refrigerant then flows into the outdoor throttling device 114. Whether the refrigerant flowing from the indoor throttling device 107 flows directly into the outdoor throttling device 114 or first flows through the subcooling pipe 113 for heat exchange before flowing into the outdoor throttling device 114 is the main difference between normal heating and low-temperature heating conditions. The key to determining whether it is normal heating or low-temperature heating lies in whether the operating parameters of the air-cooled multi-split system 100 meet the first preset condition.

[0077] After the control pipeline switching device switches to the first state in step S314, step S316 can be executed to determine whether Tao ≥ T4, Ps > P2 and t > t2, and TC1 - TC2 ≤ T5. If the determination result in step S316 is yes, step S304 is executed to switch the control pipeline switching device to the second state. In fact, the second preset condition is: the outdoor ambient temperature Tao is greater than or equal to the fourth preset temperature T4, the low pressure Ps is greater than the second preset pressure P2 and the duration t is greater than the second preset duration t2, and the difference between the air inlet pipe temperature TC1 and the liquid inlet pipe temperature TC2 is less than or equal to the fifth preset temperature T5.

[0078] Step S316 involves determining whether the operating parameters meet the second preset condition. If the determination result is yes, step S304 is executed, controlling the pipeline switching device to switch to the second state. In other words, once the pipeline switching device switches to the first state in step S314, to exit that state and switch back to the second state, the operating parameters must meet the second preset condition.

[0079] If the judgment result in step S316 is negative, step S318 is executed, and the pipeline switching device is kept in the first state. That is, after the pipeline switching device switches to the first state in step S314, if the operating parameters do not meet the second preset condition, the state of the pipeline switching device will not be switched; instead, the pipeline switching device will be kept in the first state. The judgment in step S316 regarding whether the operating parameters meet the second preset condition can be performed at regular intervals, for example, every 10 minutes.

[0080] Furthermore, the first preset condition is as follows: the outdoor ambient temperature Tao is less than the first preset temperature T1; the low-pressure Ps at the suction port of compressor 101 is less than the first preset pressure P1 and its duration t is greater than the first preset duration t1; the exhaust temperature Td is greater than or equal to the second preset temperature T2; and the difference between the intake pipe temperature TC1 and the liquid inlet pipe temperature TC2 is greater than or equal to the third preset temperature T3. If all of the above conditions are met, the first preset condition can be considered satisfied. If any one of these conditions is not met, the first preset condition can be considered not satisfied.

[0081] In one specific embodiment, the first preset temperature can be -5°C, the first preset pressure can be 3 Bar, the first preset duration can be 30 minutes, the second preset temperature can be 80°C, and the third preset temperature can be 40°C. It should be noted that the specific values ​​of the above preset parameters are merely illustrative and not intended to limit the invention. In other embodiments, different values ​​can be set according to actual conditions, but the overall values ​​should reflect the current low-temperature heating situation.

[0082] In a preferred embodiment, such as Figure 1As shown, a low-pressure sensor 118 can be installed at the suction port of the compressor 101 to detect the low-pressure at the suction port of the compressor 101 and to record the duration for which the low-pressure remains below a first preset pressure. Additionally, an external temperature sensor can be installed on the outdoor unit of the air-cooled multi-split system 100 to detect the outdoor ambient temperature. An exhaust temperature sensor can be installed on the top of the compressor 101 to detect the exhaust temperature. Intake temperature sensors and liquid inlet temperature sensors can be installed on the intake pipe and liquid inlet pipe of the indoor unit, respectively, to detect the intake pipe temperature and liquid inlet pipe temperature, respectively.

[0083] Similarly, the second preset condition is as follows: the outdoor ambient temperature Tao is greater than or equal to the fourth preset temperature T4, the low-pressure Ps is greater than the second preset pressure P2 and its duration t is greater than the second preset duration t2, and the difference between the air inlet pipe temperature TC1 and the liquid inlet pipe temperature TC2 is less than or equal to the fifth preset temperature T5. If all of the above conditions are met, the second preset condition can be considered satisfied. If any one of these conditions is not met, the second preset condition can be considered not satisfied.

[0084] In one specific embodiment, the fourth preset temperature can be 0°C, the second preset pressure can be 4 Bar, the second preset duration can be 10 minutes, and the fifth preset temperature can be 30°C. It should be noted that the specific values ​​of the above preset parameters are merely illustrative and not intended to limit the invention. In other embodiments, different values ​​can be set according to actual conditions, but the overall values ​​should reflect that the current situation is no longer characterized by low-temperature heating.

[0085] It is important to emphasize that when the pipeline switching device is switched to the first state, the refrigerant flows sequentially through the compressor 101, oil separator 103, four-way valve 104, gas pipe shut-off valve 108, indoor heat exchanger 106, indoor throttling device 107, liquid pipe shut-off valve 105, subcooling pipe 113, first solenoid valve 110, outdoor throttling device 114, outdoor heat exchanger 112, four-way valve 104, gas-liquid separator 117, and compressor 101. In other words, under low-temperature heating conditions, the refrigerant flows along the aforementioned path.

[0086] When the pipeline switching device is switched to the second state, the refrigerant flows sequentially through the compressor 101, oil separator 103, four-way valve 104, gas pipe shut-off valve 108, indoor heat exchanger 106, indoor throttling device 107, liquid pipe shut-off valve 105, second solenoid valve 119, outdoor throttling device 114, outdoor heat exchanger 112, four-way valve 104, gas-liquid separator 117, and compressor 101. In other words, under normal heating conditions, the refrigerant flows along the above path.

[0087] In summary, the heating control method of the air-cooled multi-split air conditioning system in this embodiment receives a trigger signal for the air-cooled multi-split air conditioning system 100 to activate the heating mode; controls the pipeline switching device to switch to the second state, so that the refrigerant in a gas-liquid mixture state flowing from the indoor heat exchanger 106 flows through the indoor throttling device 107 and then into the outdoor throttling device 114; controls the air-cooled multi-split air conditioning system 100 to complete one defrosting process, and when the operating parameters of the air-cooled multi-split air conditioning system 100 meet the first preset condition, controls the pipeline switching device to switch to the first .... The gas-liquid mixture of refrigerant flows into the subcooling pipe 113, where it exchanges heat with the refrigerant, further liquefying the gaseous refrigerant. When the operating parameters meet the second preset conditions, the control pipe switching device switches to the second state. The pipe switching device is adjusted according to the actual situation to make the refrigerant flow path reasonable, increase the refrigerant circulation volume of the system, and use the heat that should have been dissipated to preheat the bottom of the gas-liquid separator 117, effectively saving energy, avoiding additional replacement or addition of equipment or consumption of electricity, and greatly reducing operating costs.

[0088] It should be noted that the heating control method of the air-cooled multi-split air conditioning system in this embodiment can be mainly applied to the case where the air-cooled multi-split air conditioning system 100 is operating in heating mode. When the air-cooled multi-split air conditioning system 100 is operating in cooling mode, the heating control method of the air-cooled multi-split air conditioning system in this embodiment can be referred to, and the relevant steps can be adjusted. By adjusting the refrigerant flow path in a similar manner, the purpose of increasing the refrigerant circulation volume of the system and improving the overall energy efficiency of the system can also be achieved.

[0089] In addition, the air-cooled multi-split air conditioning system 100 may include a controller 300. Figure 4 This is a schematic block diagram of the controller 300 of an air-cooled multi-split air conditioning system according to an embodiment of the present invention. Figure 4 As shown, the controller 300 may include a processor 310 and a memory 320. The memory 320 stores a machine-executable program 321. When the machine-executable program 321 is executed by the processor 310, it is used to implement the heating control method of any of the above-mentioned air-cooled multi-split air conditioning systems.

[0090] Processor 310 can be a central processing unit (CPU), a digital processing unit, etc. Processor 310 sends and receives data via a communication interface. Memory 320 is used to store the machine-executable program 321 executed by processor 310. Memory 320 can be any medium capable of carrying or storing desired program code in the form of instructions or data structures that is accessible by a computer, or it can be a combination of multiple memories 320. The aforementioned machine-executable program 321 can be downloaded from a computer-readable storage medium to the appropriate computing / processing device or downloaded and installed to controller 300 via a network (e.g., the Internet, local area network, wide area network, and / or wireless network).

[0091] The air-cooled multi-split air conditioning system 100 in this embodiment can increase the refrigerant circulation volume of the system by setting the subcooling pipe 113, especially the refrigerant circulation volume under low temperature heating conditions, which can effectively improve the overall energy efficiency of the system; it can use the heat that should be dissipated to preheat the bottom of the gas-liquid separator 117, which can effectively save energy, avoid additional replacement or addition of equipment or consumption of electricity, and greatly reduce operating costs.

[0092] This embodiment also provides a machine-readable storage medium 400. Figure 5 This is a schematic diagram of a machine-readable storage medium 400 according to an embodiment of the present invention. The machine-readable storage medium 400 stores a machine-executable program 321. When the machine-executable program 321 is executed by the processor 310, it implements the heating control method of the air-cooled multi-split air conditioning system of any of the above embodiments.

[0093] The machine-readable storage medium 400 of this embodiment may be an electronic memory such as flash memory, EEPROM (Electrically Erasable Programmable Read-Only Memory), EPROM, hard disk, or ROM. The machine-readable storage medium 400 has storage space for a machine-executable program 321 for performing any of the method steps described above. These machine-executable programs 321 can be read from or written to one or more computer program products. These computer program products include program code carriers such as hard disks, CDs, memory cards, or floppy disks. When the device containing the machine-readable storage medium 400 runs the machine-executable program 321, it can perform the various steps of the methods described above.

[0094] In the description of this embodiment, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0095] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. A heating control method for an air-cooled multi-split air conditioning system, wherein the air-cooled multi-split air conditioning system comprises: The method includes: an indoor heat exchanger, subcooling pipes, and a piping switching device. Detect the operating parameters of the air-cooled multi-split air conditioning system; Determine whether the operating parameters meet the first preset condition; and If so, control the pipeline switching device to switch to the first state so that the gas-liquid mixed refrigerant flowing out of the indoor heat exchanger flows into the subcooling pipe, and uses the subcooling pipe to exchange heat with the refrigerant, so that the gaseous refrigerant is further liquefied; The steps for detecting the operating parameters of the air-cooled multi-split air conditioning system include: detecting the outdoor ambient temperature, the low pressure at the compressor's suction port, the exhaust temperature, and the temperature of the indoor unit's air intake pipe and liquid inlet pipe. The step of determining whether the operating parameters meet the first preset conditions includes: determining whether the outdoor ambient temperature is less than the first preset temperature, whether the low pressure at the compressor's intake port is less than the first preset pressure and the duration is greater than the first preset duration, whether the exhaust temperature is greater than or equal to the second preset temperature, and whether the difference between the intake pipe temperature and the liquid inlet pipe temperature is greater than or equal to the third preset temperature.

2. The method according to claim 1, wherein, The indoor heat exchanger is configured to condense and liquefy the gaseous refrigerant to release heat; and The air-cooled multi-split system further includes: an outdoor heat exchanger configured to vaporize the liquid refrigerant to absorb heat from the outdoor environment; and a gas-liquid separator connected to the outdoor heat exchanger and configured to separate the refrigerant flowing out of the outdoor heat exchanger into gas and liquid components, wherein the subcooling pipe is disposed at the bottom of the gas-liquid separator.

3. The method according to claim 2, wherein, The air-cooled multi-split air conditioning system further includes: an indoor throttling device connected to the indoor heat exchanger, configured to regulate the flow rate of the refrigerant and be fully open, wherein when the pipeline switching device is switched to the first state, the refrigerant in a gas-liquid mixed state flowing out of the indoor heat exchanger flows through the indoor throttling device and then into the subcooling pipe; and an outdoor throttling device connected to the outdoor heat exchanger, configured to regulate the flow rate of the refrigerant and be partially open, wherein when the pipeline switching device is switched to the first state, the refrigerant that has undergone heat exchange through the subcooling pipe flows through the outdoor throttling device and then into the outdoor heat exchanger.

4. The method according to claim 3, wherein prior to the step of detecting the operating parameters of the air-cooled multi-split air conditioning system, it further comprises: Receive the trigger signal for the air-cooled multi-split air conditioning system to start the heating mode; The pipeline switching device is controlled to switch to the second state so that the refrigerant in the gas-liquid mixed state flowing out of the indoor heat exchanger flows through the indoor throttling device and then into the outdoor throttling device; as well as Control the air-cooled multi-split air conditioning system to complete one defrosting process.

5. The method according to claim 4, wherein, If the operating parameters do not meet the first preset condition, the pipeline switching device is controlled to remain in the second state.

6. The method of claim 4, further comprising, after the step of controlling the pipeline switching device to switch to the first state: Determine whether the operating parameters meet the second preset condition; as well as If so, execute the step of controlling the pipeline switching device to switch to the second state. If not, the pipeline switching device is kept in the first state.

7. The method according to claim 6, wherein the step of determining whether the operating parameters meet the second preset condition includes: Determine whether the outdoor ambient temperature is greater than or equal to a fourth preset temperature, the low pressure is greater than a second preset pressure and the duration is greater than a second preset duration, and the difference between the air inlet pipe temperature and the liquid inlet pipe temperature is less than or equal to a fifth preset temperature.

8. The method according to claim 6, wherein, The pipeline switching device includes a first solenoid valve and a second solenoid valve, wherein the first solenoid valve is disposed between the subcooling pipe and the outdoor throttling device, and the second solenoid valve is disposed between the indoor throttling device and the outdoor throttling device.

9. The method according to claim 8, wherein, The steps of controlling the pipeline switching device to switch to the first state include: controlling the first solenoid valve to open and the second solenoid valve to close; The steps for controlling the pipeline switching device to switch to the second state include: controlling the first solenoid valve to close and the second solenoid valve to open.

10. An air-cooled multi-split air conditioning system, comprising: A controller, comprising a memory and a processor, wherein the memory stores a machine-executable program that, when executed by the processor, implements the heating control method for an air-cooled multi-split air conditioning system according to any one of claims 1 to 9.

11. A machine-readable storage medium having a machine-executable program stored thereon, the machine-executable program being executed by a processor to implement the heating control method for an air-cooled multi-split air conditioning system according to any one of claims 1 to 9.

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