Rapid oil return method of heat pump system

Abstract

The invention provides a quick oil return method of a heat pump system, which comprises the following steps of: before a compressor is started, judging whether refrigerant deposition exists or not according to environment temperature and shutdown duration; if refrigerant deposition exists, an auxiliary electronic expansion valve control program is started, and if refrigerant deposition does not exist, a heat pump is started according to a normal program; an auxiliary road electronic expansion valve control program is started, the exhaust superheat degree is judged and compared with a monitoring reference threshold value, and whether control is conducted according to the exhaust superheat degree or the injection superheat degree or not is determined; meanwhile, the exhaust superheat degree is compared with a plurality of pressure threshold values, the injection superheat degree is compared with a plurality of temperature threshold values, and the opening degree of an auxiliary road electronic expansion valve is determined; and determining that the temperature, pressure and exhaust superheat degree of the compressor are within normal ranges, determining that the flow rate of the refrigerant is stable, unlocking a control program of an auxiliary electronic expansion valve, quitting a quick oil return mode, and recovering to an automatic control mode of the heat pump. Reliable operation of the compressor is ensured, and the product reliability is greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of heat pump intelligent control, and in particular to a fast oil return method for a heat pump system. Background Art

[0002] The heat pump industry is currently in a period of rapid growth. Air source heat pump products are widely popular for their multi-purpose functions of cooling, heating and hot water production. The operating environment temperature range of the heating mode can reach -35℃ to 45℃. Generally, the indoor temperature is always maintained at a high value. In the low temperature outdoor environment, especially in cold areas, the indoor medium is a high-temperature heat source and the outdoor medium is a low-temperature heat source. Due to the driving force of the indoor and outdoor temperature difference, when the unit is shut down for a long time, the refrigerant in the unit system gradually migrates from the high-temperature heat source side to the low-temperature heat source side. Finally, a large amount of refrigerant is deposited in the compressor refrigeration oil pool in liquid form, causing the following problems: (1) The liquid refrigerant deposited in the compressor oil pool will release the refrigeration oil, making the lubrication properties of the refrigeration oil worse, and the compressor is prone to wear or even damage when it is started; (2) When the compressor is started again, the oil temperature gradually rises, causing a large amount of liquid refrigerant deposited in the oil pool to evaporate and boil, and a large amount of refrigeration oil in the compressor oil pool is taken away to the system; the compressor is in a process of running without oil for a period of time, resulting in abnormal wear of the running parts in the compressor and damage and scrapping.

[0003] Prior art 1, application number: CN 202310858806.3 discloses a gas-liquid separator with high efficiency oil return, a refrigeration / heat pump system, a gas-liquid separator body, an oil return device and an ejector pipe; the oil return device liquid inlet is connected to the oil return port through an oil delivery pipe, and a regulating valve for controlling the flow is provided on the oil delivery pipe. The oil delivery pipe and the oil return device liquid inlet are lower than the oil return port in the vertical direction, and the oil return device gas outlet is connected to the ejection fluid inlet of the ejector pipe, and the other two ports of the ejector pipe are respectively connected to the gas outlet pipe and the compressor gas return pipe. Although the gas-liquid separator has a simple structure, it can conveniently and effectively control the circulation amount of lubricating oil, improve the purity of the return oil, prevent liquid hammer when the compressor is started, improve the superheat of the compressor return gas, and improve the performance, stability and heat exchange efficiency of the refrigeration / heat pump system using the gas-liquid separator. However, the lack of judgment on the refrigerant oil used for internal lubrication of the compressor reduces the reliability of the compressor to a certain extent, which is not conducive to effectively improving the efficiency of heat pump refrigeration or heating.

[0004] Prior art 2, application number: CN202311480730.1 discloses a gas-liquid separator and a heat pump unit, including a shell; a return pipe, the return pipe is arranged in the shell, and the return pipe has a first oil return port and a second oil return port, the first oil return port is located at the bottom of the shell, the second oil return port is located at the liquid surface in the shell, and the second oil return port can move with the change of the liquid surface. The gas-liquid separator and the heat pump unit, by arranging the first oil return port and the second oil return port on the return pipe, the first oil return port is arranged at the bottom of the gas-liquid separator for normal oil return, ensuring that the compressor can always get part of the refrigeration oil to ensure the normal operation of the compressor, ensuring that the oil return of the heat pump unit under normal working conditions is reliable, and then the second oil return port is arranged at the liquid surface, and the refrigeration oil above the liquid refrigerant is drained into the compressor, although the oil supply to the compressor is increased, the oil supply of the compressor can be effectively guaranteed to be reliable. However, the lack of judgment on whether the refrigerant is deposited makes the lubrication properties of the refrigeration oil worse, and the compressor is easily worn or even damaged when starting.

[0005] Prior art three, application number: CN202310652419.4gk A static start ultra-low temperature heat pump system gas replenishment and oil return device and its operation method, including a heat pump system, wherein the heat pump system includes a compressor, the high pressure outlet of the compressor is connected to the first interface of the electromagnetic four-way valve, the second interface of the electromagnetic four-way valve is connected to the first refrigerant inlet of the refrigerant side heat exchanger, the first refrigerant outlet of the refrigerant side heat exchanger is connected to the second refrigerant inlet of the refrigerant side heat exchanger, the second refrigerant outlet of the refrigerant side heat exchanger is connected to the third interface of the electromagnetic four-way valve, the fourth interface of the electromagnetic four-way valve is connected to the low pressure inlet of the compressor, one end of the bypass electromagnetic valve electrically connected to the central controller is connected to the high pressure outlet of the compressor, and the other end of the bypass electromagnetic valve is connected to the low pressure inlet of the compressor, and the central controller controls the on and off of the bypass electromagnetic valve according to the size of the low pressure value. Although the compressor operation reliability and the service life of the compressor of the heat pump system are increased, its structure is relatively simple and lacks intelligent control equipment, resulting in the problem of slow pressure regulation speed and low efficiency.

[0006] At present, the existing technologies 1, 2 and 3 have the problem that a large amount of liquid refrigerant deposited in the oil pool of the compressor during long-term shutdown will dilute the refrigeration oil, making the lubrication properties of the refrigeration oil worse, and the compressor is easily worn or even damaged when it is started; and when the compressor is started again, a large amount of refrigeration oil in the oil pool of the compressor is taken away to the system, causing the compressor to run without oil for a period of time, resulting in abnormal wear and damage of the running parts in the compressor. Therefore, the present invention provides a method for quickly returning oil to a heat pump system. When the electronic control determines that there is refrigerant deposition at startup, the auxiliary electronic expansion valve is controlled to make the oil that escapes from the compressor in large quantities during the refrigerant deposition startup phase quickly return to the compressor, ensuring that the running parts in the compressor always have sufficient refrigerant oil for lubrication, and ensuring the reliable operation of the compressor. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides a rapid oil return method for a heat pump system, comprising the following steps:

[0008] Before the compressor is started, the ambient temperature and downtime are obtained, and whether there is refrigerant deposition is determined based on the ambient temperature and downtime; if there is refrigerant deposition, the auxiliary circuit electronic expansion valve control program is started; if there is no refrigerant deposition, the heat pump is started according to the normal program;

[0009] Start the auxiliary electronic expansion valve control program, judge the exhaust superheat and compare it with the monitoring reference threshold, and confirm whether to control according to the exhaust superheat or injection superheat; at the same time, compare the exhaust superheat with multiple pressure thresholds, and compare the injection superheat with multiple temperature thresholds to confirm the opening of the auxiliary electronic expansion valve;

[0010] Confirm that the compressor temperature, pressure and exhaust superheat are within the normal range, confirm that the refrigerant flow rate is stable, unlock the auxiliary electronic expansion valve control program, exit the fast oil return mode, and return to the automatic control mode of the heat pump.

[0011] Optionally, the process of determining whether there is refrigerant deposition based on the ambient temperature and the downtime duration includes the following steps:

[0012] The current ambient temperature of the compressor area is collected through the ambient temperature sensor device, and the downtime of the compressor is recorded and monitored in real time from the heat pump system. The acquired ambient temperature and downtime duration are integrated to form a data set.

[0013] Construct a refrigerant deposition judgment model, train it through the input of multi-dimensional features of ambient temperature and downtime, and identify the potential pattern of refrigerant deposition; output the probability value of refrigerant deposition; when the probability value exceeds the judgment threshold, it is considered that refrigerant deposition exists;

[0014] Depending on whether there is refrigerant deposition, it is determined whether to start the auxiliary electronic expansion valve control program or start the heat pump according to the normal program; when there is refrigerant deposition, the auxiliary electronic expansion valve control program is started, and the heat pump started by the normal program is in a stopped state.

[0015] Optionally, the process of forming a data set includes the following steps:

[0016] A short-time polling strategy is used to obtain temperature readings from the temperature sensor, and multiple temperature measurement data are obtained within a time interval to form a temperature fluctuation map; a timer is used to record the start and stop time of the compressor in real time, automatically sense the state change of the compressor, and start timing when the compressor is detected to be stopped. The record includes the continuous shutdown time of the compressor and the total shutdown time;

[0017] The collected ambient temperature and downtime are integrated and normalized in real time to form a multi-dimensional data set; feature extraction is performed on the temperature and time data to generate additional features, including the temperature change rate, to show the rapid change of temperature, downtime mode, and identify which mode is related to refrigerant deposition;

[0018] The integrated and normalized data sets are stored in the database; at the same time, version control of the data sets is implemented, and each version of data is saved for different operation cycles.

[0019] Optionally, the process of constructing a refrigerant deposition judgment model includes the following steps:

[0020] From the data set, extract the characteristics of factors that affect the deposition of added refrigerant, including temperature change rate, cumulative downtime and stability index; divide the data set into training set, validation set and test set;

[0021] The random forest was applied to the training set to train the refrigerant deposition judgment model, and the cross-validation method was used in the optimization process to adjust the hyperparameters;

[0022] The performance of the trained refrigerant deposition judgment model is evaluated using the validation set. The evaluation indicators include: accuracy, precision and recall rate; the probability value of refrigerant deposition is output; the verified refrigerant deposition judgment model is embedded in the real-time monitoring system, set to automatic operation mode, and receive real-time ambient temperature and downtime duration data for analysis.

[0023] Optionally, the setting process of the auxiliary electronic expansion valve control program includes the following steps:

[0024] Design a multi-level control program that includes data analysis, decision execution, and operation feedback. The first level is responsible for real-time data collection and status evaluation, the second level is responsible for judgment logic and control decision-making, and the last level is responsible for execution and feedback;

[0025] The trained refrigerant deposition judgment model is used to analyze the ambient temperature and downtime duration, and the probability value of refrigerant deposition is output. When the probability value exceeds the set threshold, the flag signal of refrigerant deposition is immediately triggered. After the refrigerant deposition is judged to exist, the working mode will be switched immediately according to the pre-set priority rules, and the opening degree of the auxiliary electronic expansion valve will be adjusted to respond to the demand for refrigerant flow. At the same time, the heat pump stop command is automatically sent to cut off the heat pump startup program.

[0026] After obtaining the signal of refrigerant deposition, a stop signal is sent to the heat pump control loop through a programmable logic controller; a state feedback loop is established to detect the heat pump output status in real time through sensors to ensure that the stop command is effectively executed; if the feedback signal shows that the heat pump is still in the startup state, the fault handling mechanism will be activated, the stop command will be resent and the fault will be checked.

[0027] Optionally, the process of controlling according to the exhaust superheat or the injection superheat comprises the following steps:

[0028] The auxiliary circuit electronic expansion valve opens to the preset initial opening and maintains the state;

[0029] After the initial opening is set, real-time monitoring and adjustment are performed for the exhaust superheat. According to different superheat ranges, the opening of the auxiliary electronic expansion valve is adjusted according to the set conditions;

[0030] When the compressor is turned on and the exhaust superheat is detected for the first time to exceed the set monitoring reference threshold, the auxiliary electronic expansion valve exits the control mode of the refrigerant deposition startup phase and enters the exhaust or injection superheat regulation.

[0031] Optionally, the process of obtaining the exhaust superheat comprises the following steps:

[0032] The exhaust temperature sensor is used to monitor the actual temperature of the compressor exhaust end in real time; at the same time, the high pressure sensor monitors the high pressure value;

[0033] According to the known high pressure value, query the refrigerant characteristic table, and use the relationship between the saturated vapor pressure and the corresponding temperature of the refrigerant to calculate the saturation temperature corresponding to the pressure;

[0034] The exhaust superheat is obtained by subtracting the actual temperature from the saturation temperature, thereby determining the safety of the compressor exhaust state.

[0035] Optionally, the process of obtaining the injection superheat comprises the following steps:

[0036] Use the auxiliary output temperature sensor to monitor the temperature of the auxiliary output end in real time; at the same time, use the auxiliary input temperature sensor to monitor the temperature of the auxiliary input end;

[0037] By comparing the auxiliary outlet temperature and the auxiliary inlet temperature, the temperature difference, i.e. the injection superheat, is calculated, which indicates the temperature change from the auxiliary inlet end to the auxiliary outlet end after the refrigerant passes through the system, reflecting the superheat degree of the refrigerant;

[0038] Based on the result of the injection superheat, it is compared with the set threshold. If the calculated injection superheat exceeds the preset value, the automatic adjustment mechanism will be activated to adjust the opening of the auxiliary electronic expansion valve through instant feedback.

[0039] Optionally, the process of unlocking the auxiliary electronic expansion valve control program includes the following steps:

[0040] Comprehensively monitor the temperature and pressure of the compressor, including confirming whether the compressor's exhaust superheat is within the safety threshold; use a flow sensor to monitor the refrigerant flow rate in real time. If the flow rate is stable and within the preset range, proceed to the next step;

[0041] According to the real-time monitoring results, the auxiliary electronic expansion valve opening adjustment strategy obtains the opening setting parameters; the unlocking program is automatically executed to convert the auxiliary electronic expansion valve control program from the locked state to the unlocked state;

[0042] After unlocking is completed, it will automatically switch to the automatic control mode of the heat pump; the opening of the auxiliary electronic expansion valve will be automatically adjusted according to changes in pressure, temperature and demand.

[0043] Optionally, the process of obtaining the auxiliary circuit electronic expansion valve opening adjustment strategy includes the following steps:

[0044] Collect data from multiple sensors, including compressor temperature, pressure, exhaust superheat, and refrigerant flow rate, clean the collected data, and remove outliers and noise; determine the key variables that affect the opening setting, including ambient temperature, system pressure, exhaust superheat, and refrigerant flow rate;

[0045] Based on real-time monitoring of key variables, set the objective function of maximizing refrigeration efficiency, minimizing energy consumption or minimizing exhaust superheat; use the acquired data and historical operating patterns to predict demand and adjust the opening degree;

[0046] According to the obtained opening setting parameters, a specific control instruction is generated and sent to the auxiliary electronic expansion valve; after the opening adjustment is performed and the execution is obtained, feedback is given to see whether the setting has achieved the expected effect, forming a closed-loop control.

[0047] The invention determines the refrigerant deposition and starts the control program. By obtaining the ambient temperature and the shutdown time, it can evaluate whether the system has the problem of refrigerant deposition; if refrigerant deposition is found, the auxiliary electronic expansion valve control program is started; whether the heat pump system is started normally is determined according to the refrigerant state. If refrigerant deposition exists, additional control measures are taken to avoid possible failures after startup. The significance achieved: by confirming the refrigerant state before the compressor is started, the liquid hammer phenomenon caused by the deposition of liquid refrigerant can be prevented, thereby protecting the safety of the compressor and system components; ensuring that the heat pump can be started under stable conditions, reducing the number of maintenance and shutdowns caused by refrigerant problems, and improving the reliability of the equipment. The startup of the control program is compared with the threshold, the auxiliary electronic expansion valve control program is started, the exhaust superheat and the injection superheat are monitored in real time, and compared with the reference threshold; check whether the exhaust superheat is within the preset multiple pressure threshold ranges, and whether the injection superheat is within the set multiple temperature threshold ranges; adjust the opening of the auxiliary electronic expansion valve according to the comparison results to achieve the best refrigerant flow and system operation. Significance achieved: Through precise adjustment, the heat pump can maintain good performance in the stage of rapid oil return, achieve rapid and effective refrigerant return, and ensure efficient operation of the system; optimized refrigerant flow helps to improve the energy efficiency ratio (COP) of the heat pump, reduce energy consumption, and thus improve overall economy. Confirm the status of the heat pump and restore automatic control, confirm that key parameters such as compressor temperature, pressure, and exhaust superheat are within the normal range, and confirm the stability of the refrigerant flow rate; after the heat pump status is confirmed to be correct, unlock the auxiliary electronic expansion valve control program, exit the rapid oil return mode, and return to the normal heat pump automatic control mode. Significance achieved: Ensure that all parameter settings are in a safe and stable state before entering the normal control mode, thereby avoiding instability and potential failures during operation; achieve seamless switching between rapid oil return and normal operation, so that the heat pump system can maintain good continuity during operation and improve work efficiency.

[0048] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0049] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0051] Figure 1This is a flow chart of a rapid oil return method for a heat pump system in Example 1 of the present invention;

[0052] Figure 2 This is a process diagram for determining whether there is refrigerant deposition according to the ambient temperature and the downtime duration in Example 2 of the present invention;

[0053] Figure 3 A process diagram of forming a data set in Embodiment 3 of the present invention;

[0054] Figure 4 This is a process diagram of constructing a refrigerant deposition judgment model in Example 4 of the present invention;

[0055] Figure 5 This is a setting process diagram of the auxiliary circuit electronic expansion valve control program in Example 5 of the present invention;

[0056] Figure 6 This is a process diagram for controlling according to exhaust superheat or injection superheat in Embodiment 6 of the present invention;

[0057] Figure 7 FIG. 1 is a diagram of the process of obtaining the exhaust superheat in Example 7 of the present invention;

[0058] Figure 8 FIG. 8 is a process diagram for obtaining the injection superheat in Example 8 of the present invention;

[0059] Fig. 9 This is a process diagram of a control program for unlocking an auxiliary circuit electronic expansion valve in Embodiment 9 of the present invention;

[0060] Fig.10 This is a diagram of the process of obtaining the auxiliary circuit electronic expansion valve opening adjustment strategy in Embodiment 10 of the present invention;

[0061] Fig.11 This is a structural block diagram of the heat pump system in Example 11 of the present invention. DETAILED DESCRIPTION

[0062] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0063] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The singular forms of "a", "said" and "the" used in the embodiments of the present application are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items.

[0064] When the following description relates to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are only examples of devices and methods consistent with some aspects of the present application. In the description of the present application, it should be understood that the terms "first", "second", "third", etc. are only used to distinguish similar objects, and do not have to be used to describe a specific order or sequence, nor can they be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0065] Example 1: Figure 1 As shown, an embodiment of the present invention provides a method for rapid oil return of a heat pump system, comprising the following steps:

[0066] S100: Before the compressor is started, the ambient temperature and downtime are obtained, and whether there is refrigerant deposition is determined according to the ambient temperature and downtime; if there is refrigerant deposition, the auxiliary circuit electronic expansion valve control program is started; if there is no refrigerant deposition, the heat pump is started according to the normal program;

[0067] S200: Start the auxiliary electronic expansion valve control program, judge the exhaust superheat and compare it with the monitoring reference threshold, confirm whether to control according to the exhaust superheat or the injection superheat; at the same time, compare the exhaust superheat with multiple pressure thresholds, and compare the injection superheat with multiple temperature thresholds to confirm the opening of the auxiliary electronic expansion valve;

[0068] S300: Confirm that the compressor temperature, pressure and exhaust superheat are within the normal range, confirm that the refrigerant flow rate is stable, unlock the auxiliary electronic expansion valve control program, exit the fast oil return mode, and return to the automatic control mode of the heat pump.

[0069] The working principle and beneficial effects of the above technical solution are as follows: This embodiment first obtains the ambient temperature and shutdown time before starting the compressor, and determines whether there is refrigerant deposition based on the ambient temperature and the shutdown time; if there is refrigerant deposition, the auxiliary electronic expansion valve control program is started, and if there is no refrigerant deposition, the heat pump is started according to the normal procedure; secondly, the auxiliary electronic expansion valve control program is started to judge the exhaust superheat and compare it with the monitoring reference threshold to confirm whether to control it according to the exhaust superheat or the injection superheat; at the same time, the exhaust superheat is compared with multiple pressure thresholds, and the injection superheat is compared with multiple temperature thresholds to confirm the opening of the auxiliary electronic expansion valve; finally, it is confirmed that the compressor temperature, pressure and exhaust superheat are within the normal range, and the refrigerant flow rate is confirmed to be stable, the auxiliary electronic expansion valve control program is unlocked, the fast oil return mode is exited, and the heat pump is restored to the automatic control mode. In the above scheme, step S100 determines the refrigerant deposition and starts the control program. By obtaining the ambient temperature and the shutdown time, it can be evaluated whether the system has the problem of refrigerant deposition; if refrigerant deposition is found, the auxiliary electronic expansion valve control program is started; whether the heat pump system is started normally is determined according to the refrigerant state. If refrigerant deposition exists, additional control measures are taken to avoid possible failures after startup. The significance achieved: by confirming the refrigerant state before the compressor is started, the liquid hammer phenomenon caused by the deposition of liquid refrigerant can be prevented, thereby protecting the safety of the compressor and system components; ensuring that the heat pump can be started under stable conditions, reducing the number of maintenance and shutdowns caused by refrigerant problems, and improving the reliability of the equipment. Step S200 controls the startup of the program and compares it with the threshold, starts the auxiliary electronic expansion valve control program, monitors the exhaust superheat and injection superheat in real time, and compares them with the reference threshold; checks whether the exhaust superheat is within the preset multiple pressure thresholds, and whether the injection superheat is within the set multiple temperature thresholds; adjusts the opening of the auxiliary electronic expansion valve according to the comparison results to achieve the best refrigerant flow and system operation. Significance achieved: Through precise adjustment, the heat pump can maintain good performance in the stage of rapid oil return, achieve rapid and effective refrigerant return, and ensure efficient operation of the system; optimized refrigerant flow helps to improve the energy efficiency ratio (COP) of the heat pump, reduce energy consumption, and thus improve overall economy. Step S300 confirms the state of the heat pump and resumes automatic control, confirms that key parameters such as compressor temperature, pressure, and exhaust superheat are within the normal range, and confirms the stability of the refrigerant flow rate; after the heat pump state is confirmed to be correct, unlock the auxiliary electronic expansion valve control program, exit the rapid oil return mode, and return to the normal heat pump automatic control mode. Significance achieved: Ensure that all parameter settings are in a safe and stable state before entering the normal control mode, thereby avoiding instability and potential failures during operation; achieve seamless switching between rapid oil return and normal operation, so that the heat pump system can maintain good continuity during operation and improve work efficiency.

[0070] In summary, this embodiment ensures the safety and stability of the refrigerant during the startup and operation of the compressor by gradually detecting and executing specific control programs, which not only avoids the occurrence of faults, but also optimizes the operating efficiency and economy of the system. Through monitoring and adjustment at different stages, high-efficiency operation and management of the heat pump system are achieved; by controlling the auxiliary electronic expansion valve, the oil that escapes from the compressor in large quantities during the startup phase of refrigerant deposition is quickly returned to the compressor, ensuring that the operating parts in the compressor always have sufficient refrigeration oil lubrication, ensuring the reliable operation of the compressor, and greatly improving product reliability.

[0071] Example 2: Figure 2 As shown, based on Example 1, the process of judging whether there is refrigerant deposition according to the ambient temperature and the downtime duration provided in the embodiment of the present invention includes the following steps:

[0072] S101: collecting the current ambient temperature of the compressor area through the ambient temperature sensor device, obtaining real-time monitoring from the heat pump system and recording the downtime of the compressor; integrating the acquired ambient temperature and downtime duration to form a data set;

[0073] S102: construct a refrigerant deposition judgment model, train it through the input of multi-dimensional features of ambient temperature and downtime, and identify the potential pattern of refrigerant deposition; output the probability value of refrigerant deposition; when the probability value exceeds the judgment threshold, it is considered that refrigerant deposition exists;

[0074] S103: Determine whether to start the auxiliary electronic expansion valve control program or start the heat pump according to the normal program based on whether there is refrigerant deposition; when there is refrigerant deposition, start the auxiliary electronic expansion valve control program, and the heat pump started by the normal program is in a stopped state.

[0075] The working principle and beneficial effects of the above technical solution are as follows: In this embodiment, the current ambient temperature of the compressor area is first collected by the ambient temperature sensing device, and the compressor downtime is obtained from the heat pump system in real time for monitoring and recording; the acquired ambient temperature and downtime are integrated to form a data set; secondly, a refrigerant deposition judgment model is constructed, and the potential pattern of refrigerant deposition is identified by training through the input ambient temperature and downtime multi-dimensional features; the probability value of the existence of refrigerant deposition is output; when the probability value exceeds the judgment threshold, it is deemed that refrigerant deposition exists; finally, according to whether there is refrigerant deposition, it is determined whether to start the auxiliary electronic expansion valve control program or start the heat pump according to the normal program; when there is refrigerant deposition, the auxiliary electronic expansion valve control program is started, and the normal program starts the heat pump in a stopped state. Step S101 of the above scheme collects and integrates the temperature data of the compressor area in real time through the ambient temperature sensing device, and records the downtime of the compressor at the same time to ensure the accuracy and real-time nature of the data; the collected ambient temperature and downtime are integrated to form a multidimensional data set that is helpful for subsequent analysis. Significance: The formation of the data set provides a basis for the next step of judgment, ensuring that there is sufficient information support for subsequent modeling and analysis; real-time monitoring and recording help to fully understand the state of the compressor, accurately grasp the operating environment of the equipment, and help improve the safety and effectiveness of operation; obtain time-sensitive data so that the system can quickly identify and respond to changes in the state of the refrigerant, reducing the impact on equipment performance. Step S102 Model construction and refrigerant deposition judgment, the constructed refrigerant deposition judgment model can identify the potential pattern of refrigerant deposition through the input temperature and downtime parameters, and improve the accuracy of judgment; the output of the model is the probability value of refrigerant deposition, allowing the system to make more detailed judgments under dynamic conditions. Significance: Through the intelligent analysis capability of the model, it is possible to quickly and accurately determine whether the refrigerant is deposited, solving the limitations of traditional static monitoring methods; the dynamic probability output reduces the uncertainty brought by previous experience judgments, thereby reducing the risk of false alarms and missed alarms and improving the reliability of the system; the judgment model can adapt to different environmental conditions, support a variety of operating strategies and condition changes, and improve the intelligence level of the system. Step S103 determines the start of the control program. According to the judgment of whether there is refrigerant deposition, the control strategy is automatically switched to enable the auxiliary electronic expansion valve or restore the normal mode. Once the refrigerant deposition is confirmed, the corresponding control program is immediately started to ensure the smooth flow of refrigerant and prevent potential failures. Significance: By quickly responding to this state, the risk of system failure caused by deposition is reduced and the service life of the equipment is extended; by reasonably controlling the flow of refrigerant, the system energy efficiency is improved, the performance of the heat pump is maintained, and it can operate efficiently in different working modes; the intelligent and efficient control of the system is realized, the user's trust in the heat pump is enhanced during use, and user satisfaction is improved.

[0076] In summary, this embodiment not only improves the intelligence level and operational safety of the system, but also realizes effective management and optimization of refrigerant deposition through advanced data collection and processing, intelligent judgment and control. It has significant technical advantages in the face of equipment complexity and environmental variables, and helps to promote the development of heat pump systems in a more efficient and autonomous direction, thereby improving competitiveness in the market.

[0077] Example 3: Figure 3 As shown, based on Example 2, the process of forming a data set provided in this embodiment of the present invention includes the following steps:

[0078] S1011: A short-time polling strategy is used to obtain temperature readings from the temperature sensor, and multiple temperature measurement data are obtained within a time interval to form a temperature fluctuation map; a timer is used to record the start and stop time of the compressor in real time, and the compressor state change is automatically sensed. When the compressor is detected to be stopped, the timing is started, wherein the record includes the continuous stop time of the compressor and the total stop time;

[0079] S1012: Integrate and normalize the collected ambient temperature and downtime in real time to form a multi-dimensional data set; extract features from the temperature and time data to generate additional features, including the temperature change rate, to show the rapid change of temperature, downtime mode, and identify which mode is related to refrigerant deposition;

[0080] S1013: The integrated and normalized data set is stored in a database; at the same time, version control of the data set is implemented, and each version of data is saved for different operation cycles.

[0081] The working principle and beneficial effects of the above technical solution are as follows: This embodiment first adopts a short-time polling strategy to obtain temperature readings from a temperature sensor, obtains multiple temperature measurement data within a time interval, and forms a temperature fluctuation map; a timer is used to record the start-up and shutdown time of the compressor in real time, automatically senses the state change of the compressor, and starts timing when the compressor is detected to be shut down, wherein the record includes the duration of continuous shutdown of the compressor and the total shutdown time; secondly, the collected ambient temperature and shutdown time are integrated and normalized in real time to form a multidimensional data set; feature extraction is performed on the temperature and time data to generate additional features, including the temperature change rate, which is used to show the rapid change of temperature, the shutdown mode, and identify which mode is related to the refrigerant deposition; finally, the integrated and normalized data set is stored in the database; at the same time, version control of the data set is implemented, and each version of the data is saved for different operating cycles. Step S1011 of the above scheme collects temperature and downtime data. It adopts a short-time polling strategy to obtain frequent temperature readings from the temperature sensor to ensure that the instantaneous temperature changes can be captured and a temperature fluctuation map can be formed. Real-time monitoring can provide a reliable temperature data basis to reflect environmental changes. The timer is used to monitor the start and stop status of the compressor in real time. It can automatically sense changes and start timing once the stop status is detected. The automatic sensing mechanism ensures accurate recording of downtime, including the duration of continuous downtime and the total downtime. Significance achieved: By real-time monitoring of temperature and stop status, it can respond quickly to environmental changes and improve the safety and reliability of the heat pump system. Frequent data measurement and recording enhance the coverage and representativeness of the data, providing an accurate basis for subsequent analysis. By monitoring the stop mode, it can provide a basis for fault warning and maintenance decisions. Step S1012: Data integration and feature extraction: real-time integration and normalization of data from different sources (temperature and downtime) to eliminate unit differences and dimension problems and form a unified multidimensional data set; based on the integrated data set, feature extraction is performed, such as calculating the temperature change rate and identifying the downtime mode; additional features help the system to deeply analyze and mine the potential refrigerant deposition mode of the data. Significance achieved: Through the formation of a multidimensional data set, the relationship between temperature and downtime can be systematically analyzed, making the effect of subsequent model construction more significant; feature extraction can provide key indicators to help determine the potential risk of refrigerant deposition and improve the accuracy of the judgment model; the integrated data and features can provide a scientific basis for operators to optimize maintenance and operation decisions, thereby improving the stability and efficiency of the overall system. Step S1013: Data storage and version control: the integrated and normalized data set is stored in the database to ensure the persistence and traceability of the data, which is convenient for subsequent analysis and query; the version control of the data set is implemented, and each version of the data is saved for different operation cycles, so that the system can track historical data for comparison, analysis and optimization.Significance achieved: Database storage ensures the long-term validity of important data and facilitates periodic review and analysis. The implementation of version control allows data to be traced back and compared under different circumstances, supporting the analysis of fault and performance change trajectories. The preservation and management of version data provides an important basis for subsequent model optimization and system improvement, and promotes continuous innovation and iteration of the system in operation.

[0082] In summary, this embodiment forms a systematic and complete data collection and processing flow, ensuring the accuracy and effectiveness of the refrigerant deposition judgment logic; each step focuses on the acquisition and processing of real-time data, and continuously reflects state changes in a dynamic environment; ensures that data integration, processing and storage are performed at high standards to ensure the effectiveness of subsequent analysis and decision-making; the above process is not only limited to data collection, but also provides strong support for the autonomous judgment and adjustment of the intelligent system, thereby improving the intelligence level and operational efficiency of the overall heat pump system.

[0083] Example 4: Figure 4 As shown, based on Example 2, the process of constructing a refrigerant deposition judgment model provided in the embodiment of the present invention includes the following steps:

[0084] S1021: Extract the characteristics of factors affecting the deposition of added refrigerant from the data set, including the temperature change rate, cumulative downtime and stability index, etc.; divide the data set into a training set, a validation set and a test set;

[0085] S1022: Apply random forest to the training set to train the refrigerant deposition judgment model, and use the cross-validation method to adjust the hyperparameters during the optimization process;

[0086] S1023: Use the validation set to perform performance evaluation on the trained refrigerant deposition judgment model, where the evaluation indicators include: accuracy, precision and recall rate; output the probability value of refrigerant deposition; embed the verified refrigerant deposition judgment model into the real-time monitoring system, set it to automatic operation mode, and receive real-time ambient temperature and downtime duration data for analysis.

[0087] The working principle and beneficial effects of the above technical solution are as follows: This embodiment first extracts the characteristics of factors affecting the deposition of added refrigerant from the data set, including the temperature change rate, the cumulative downtime and the stability index; divides the data set into a training set, a validation set and a test set; secondly, applies random forest to the training set to train the refrigerant deposition judgment model, and the optimization process adopts the cross-validation method to adjust the hyperparameters; finally, the validation set is used to evaluate the performance of the trained refrigerant deposition judgment model, and the evaluation indicators include: accuracy, precision and recall rate; outputs the probability value of refrigerant deposition; embeds the verified refrigerant deposition judgment model into the real-time monitoring system, sets it to the automatic operation mode, and receives the ambient temperature and downtime data in real time for analysis. Step S1021 of the above scheme is feature extraction and data set division. The key features that affect refrigerant deposition (such as temperature change rate, cumulative downtime and stability index) are extracted from the data set. The features can effectively capture the dynamic changes of the environment and equipment status, and help the model to more accurately identify the refrigerant deposition phenomenon; the selection and construction of features not only ensure the relevance of the input data, but also improve the model's expression ability, so that it can better reflect the causes of refrigerant deposition; the overall data set is divided into training set, validation set and test set to facilitate the training, adjustment and evaluation of the model, ensuring the reliability of the evaluation results and the generalization ability of the model; the division ensures the performance evaluation of the model on unknown data, which can effectively prevent the overfitting of the model. The significance achieved: The extracted features can help understand how various factors affect refrigerant deposition, and then provide strong data support for the design and maintenance decisions of the heat pump system; the multi-dimensional features enhance the model's ability to capture complex patterns, improve the accuracy of refrigerant deposition, and reduce the probability of false positives and false negatives. Step S1022 applies random forest to model training, and uses random forest algorithm for training. Random forest is an ensemble learning method. By constructing multiple decision trees for prediction, it effectively reduces the deviation that may be generated by a single model. The optimization process uses cross-validation, which can make full use of the information in the data set, reduce the variance of model evaluation, and ensure the robustness and reliability of the model. By properly adjusting hyperparameters (such as the number of trees, maximum depth, etc.), the prediction performance of the model can be improved, and the model parameter combination that best suits the current data characteristics can be found. Significance achieved: The random forest method performs well in processing high-dimensional data, can effectively deal with the mutual influence between features, strengthen the overall performance of the refrigerant deposition judgment model, and improve accuracy; cross-validation and hyperparameter adjustment ensure the systematic and rigorous nature of the training process, so that even in the face of complex and changing data environments, the model can still maintain a high level of discrimination.Step S1023: Model evaluation and deployment. The trained model is evaluated using the validation set, focusing on indicators such as accuracy, precision and recall. The indicators can fully demonstrate the performance of the model in various situations. The probability value of refrigerant deposition can be output to quantify the risk of refrigerant deposition and provide a basis for subsequent response decisions. The verified refrigerant deposition judgment model is embedded in the real-time monitoring system, so that the model can receive temperature and downtime data in real time for analysis. After automatic operation, the model can generate judgments autonomously and feedback results in a timely manner without manual intervention. Significance achieved: After integration into the automation system, the judgment of refrigerant deposition can be quickly fed back, and measures can be taken in a timely manner to ensure the safe and efficient operation of the heat pump system. The input of real-time operation data ensures that the model can be continuously optimized in a dynamically changing environment, so that it has adaptive capabilities and improves processing efficiency. Provide early warning for maintenance: Through the output probability value and judgment results, timely warnings are provided to maintenance personnel, and they are assisted in deciding whether to initiate corresponding maintenance or adjustment measures, thereby improving the reliability and stability of the entire heat pump system.

[0088] In summary, the process of constructing the refrigerant deposition judgment model through the above steps in this embodiment reflects the combination of data analysis, model training and real-time response mechanism. Each step has a significant impact on the performance and safety of the entire heat pump system. Overall, a closed loop from data acquisition to decision execution is achieved, providing a scientific and accurate solution for compressor control and refrigerant deposition management.

[0089] Example 5: Figure 5 As shown, based on Example 2, the setting process of the auxiliary circuit electronic expansion valve control program provided by the embodiment of the present invention includes the following steps:

[0090] S1031: Design a multi-level control program including data analysis, decision execution and operation feedback. The first level is responsible for real-time data collection and status evaluation, the second level is for judgment logic and control decision, and the last level is responsible for execution and feedback;

[0091] S1032: Analyze the ambient temperature and downtime using the trained refrigerant deposition judgment model, and output the probability value of refrigerant deposition. When the probability value exceeds the set threshold, immediately trigger the flag signal of refrigerant deposition. After judging the presence of refrigerant deposition, immediately switch the working mode according to the pre-set priority rules, adjust the opening degree of the auxiliary electronic expansion valve, and respond to the demand for refrigerant flow. At the same time, automatically send a stop command for the heat pump to cut off the heat pump startup program.

[0092] S1033: After obtaining the signal of the presence of refrigerant deposition, a stop signal is sent to the heat pump control loop through a programmable logic controller; a state feedback loop is established to detect the heat pump output status in real time through sensors to ensure that the stop command is effectively executed; if the feedback signal shows that the heat pump is still in the startup state, the fault handling mechanism will be activated, the stop command will be resent and fault troubleshooting will be performed.

[0093] The working principle and beneficial effects of the above technical solution are as follows: In this embodiment, a multi-level control program including three levels of data analysis, decision execution and operation feedback is first designed. The first level is responsible for real-time data collection and state evaluation, the second level performs judgment logic and control decision, and the last level is responsible for execution and feedback; secondly, the trained refrigerant deposition judgment model is used to analyze the ambient temperature and shutdown time, and the probability value of the existence of refrigerant deposition is output. When the probability value exceeds the set threshold, the flag signal of the existence of refrigerant deposition is immediately triggered; after judging the existence of refrigerant deposition, the working mode will be immediately switched according to the pre-set priority rules, and the opening degree of the auxiliary electronic expansion valve will be adjusted to respond to the demand for refrigerant flow; at the same time, a stop heat pump instruction is automatically sent to cut off the heat pump startup program; finally, after obtaining the signal of the existence of refrigerant deposition, a stop signal is sent to the heat pump control loop through a programmable logic controller; a state feedback loop is established, and the output state of the heat pump is detected in real time through a sensor to ensure that the stop instruction is effectively executed; if the feedback signal shows that the heat pump is still in the startup state, the fault handling mechanism will be started, the stop command will be resent and the fault will be checked. The above scheme is designed with a multi-level control program in step S1031. The first level collects environmental and system status data in real time through various sensors (such as temperature, pressure, etc.), and transmits the data to the control system in real time to form a comprehensive status assessment basis; the second level uses data analysis models to identify patterns from the collected data and generate real-time decisions to ensure the accuracy of control actions; the third level is responsible for converting decisions into specific control instructions and monitoring the execution status for subsequent strategy adjustments. Significance: The design of this multi-level control program improves the flexibility and response speed of the system, enabling it to quickly feedback and optimize adjustments when facing complex environmental changes, and overall enhances the intelligence level and adaptive ability of the system. Step S1032 refrigerant deposition judgment and working mode switching, by using the trained refrigerant deposition judgment model, can analyze the collected ambient temperature and downtime, generate probability values, and judge in real time whether there is refrigerant deposition. Predictability allows the system to respond in time when the problem has not yet appeared; once the refrigerant deposition is confirmed, the system immediately adjusts the working mode according to the preset priority rules, opens the auxiliary electronic expansion valve, and issues a command to stop the heat pump. Significance: It significantly improves the active protection capability of the system, can prevent potential equipment failures, and avoid more serious consequences caused by refrigerant deposition; through the rapid response mechanism, it ensures the safety and stability of the heat pump system under complex working conditions.Step S1033 sends a stop signal and a state feedback loop. When the system confirms that there is refrigerant deposition, a stop command is sent to the heat pump control loop through the programmable logic controller (PLC) to ensure that the heat pump can be shut down in a timely and safe manner to avoid further refrigerant deposition problems; a state feedback loop is established to monitor the actual operating status of the heat pump through sensors to ensure the effective execution of the stop command; if the heat pump is still in the startup state, a stop command is reissued through the fault handling mechanism, and the fault diagnosis process is started to ensure the reliable operation of the system. Significance: It ensures the accurate transmission and feedback of the stop signal, reduces the risk that the system may cause due to command failure, and enhances the reliability and intelligent response capabilities of the entire control system; it not only ensures the safe operation of the equipment, but also provides a basis for subsequent troubleshooting and maintenance verification, and improves the maintainability of the system.

[0094] In summary, a series of setting steps in this embodiment complement each other, and an intelligent, efficient and safe auxiliary electronic expansion valve control system is constructed as a whole; by constructing a multi-level data analysis and feedback mechanism, using a judgment model for refrigerant deposition warning, and establishing an effective signal control and fault detection mechanism, active handling of the refrigerant deposition problem is achieved, which greatly improves the stability and safety of the heat pump system under complex working conditions, and provides an important reference and foundation for future applications in related fields.

[0095] Example 6: Figure 6 As shown, based on Example 1, the process of controlling according to exhaust superheat or injection superheat provided in the embodiment of the present invention includes the following steps:

[0096] S201: The auxiliary circuit electronic expansion valve is opened to a preset initial opening and maintained in this state;

[0097] S202: Complete the initial opening setting, conduct real-time monitoring and adjustment for the exhaust superheat, and adjust the opening of the auxiliary electronic expansion valve according to the set conditions according to different superheat ranges;

[0098] S203: When the compressor is turned on and the exhaust superheat is detected for the first time to exceed the set monitoring reference threshold, the auxiliary electronic expansion valve exits the control mode of the refrigerant deposition startup phase and enters the exhaust or injection superheat regulation.

[0099] The working principle and beneficial effects of the above technical solution are as follows: In this embodiment, the auxiliary electronic expansion valve is first opened to the preset initial opening at a rate of about 40P / 10s, and the state is maintained for 1-2min; secondly, the initial opening setting is completed, and the exhaust superheat is monitored and adjusted in real time. According to different superheat ranges, the opening adjustment of the auxiliary electronic expansion valve is carried out according to the set condition judgment; finally, when the compressor is turned on for 5 minutes and the exhaust superheat is detected for the first time to exceed the set monitoring reference threshold, the auxiliary electronic expansion valve exits the control mode of the refrigerant deposition startup phase and enters the regulation of exhaust or injection superheat. In the step S201 of the above scheme, the initial opening is set, and the auxiliary electronic expansion valve is opened to the preset initial opening at a rate of about 40P / 10 seconds, and maintained for 1 to 2 minutes to ensure that the refrigerant flow can be quickly established; by setting the initial opening and maintaining a fixed time, it can ensure that the appropriate refrigerant flow can be provided in the initial startup phase, avoiding flow fluctuations caused by instantaneous changes in the opening, so as to protect other components of the system (such as the compressor) from being able to withstand stable loads at startup. Significance: The establishment of the initial state provides a good foundation for subsequent fine control, ensuring the stability of the system at the initial startup, thereby reducing the adverse effects on the compressor and the entire refrigeration system. Step S202 monitors and adjusts the exhaust superheat in real time. After the initial opening setting is completed, the exhaust superheat is monitored in real time to ensure that the system working conditions are understood at any time, and the corresponding valve opening is adjusted according to different superheat ranges; based on the set condition judgment, the auxiliary electronic expansion valve can respond according to the real-time data to ensure the optimization of the refrigerant flow and prevent liquid hammer or compressor oil shortage. Significance: The real-time monitoring and adjustment mechanism enhances the system's ability to handle emergencies and improves the reliability of the system's operation; through precise control, the system can always maintain the best working condition, thereby improving overall energy efficiency and stability. Step S203: The compressor exits the refrigerant deposition startup phase after 5 minutes. When the compressor works for 5 minutes and detects for the first time that the exhaust superheat exceeds the set reference threshold, the auxiliary electronic expansion valve can automatically exit the refrigerant deposition startup control mode and switch to conventional exhaust or injection superheat regulation. The state conversion ensures that the system can respond to the changing working environment in a timely manner. After switching to the conventional regulation mode, the auxiliary electronic expansion valve continues to adjust according to the exhaust superheat or injection superheat, so that it can respond to different working conditions more flexibly in daily operation. Significance: Ensure that the system can always adapt to changing working conditions at the initial startup and during normal operation, and adjust the operation strategy in time to effectively prevent equipment damage caused by refrigerant deposition or overheating out of control; it can significantly improve the service life of the equipment and the overall efficiency of the system.

[0100] In this embodiment, before the compressor is started, it is first determined whether there is refrigerant deposition. Generally, the ambient temperature and the downtime duration are used as the determination conditions for refrigerant deposition. If there is refrigerant deposition, the following auxiliary circuit electronic expansion valve control is performed during the compressor startup stage:

[0101] After the compressor starts for a period of time, the length of time to ensure that the compressor has started stably and most of the refrigerant oil is still in the compressor oil pool is generally 2 to 5 minutes;

[0102] The auxiliary circuit electronic expansion valve opens to the initial opening at a certain rate (generally about 40P / 10s) and maintains it for a period of time (generally 1 to 2 minutes), and then determines the exhaust gas superheat to carry out the next step of control:

[0103] ① When the exhaust superheat condition of Article ② is not met, the auxiliary electronic expansion valve is controlled according to the target injection superheat to prevent compressor liquid hammer or oil shortage;

[0104] When the injection superheat is ≤T1 (the first temperature threshold), the auxiliary circuit electronic expansion valve is closed at a certain rate, generally about 3P / 10s;

[0105] When T1<injection superheat≤T2 (second temperature threshold), the auxiliary electronic expansion valve is closed at a certain rate, generally about 2P / 15s. The valve closing rate here is slower than the first step;

[0106] When T2<injection superheat ≤ T3 (third temperature threshold), the auxiliary electronic expansion valve maintains the current opening;

[0107] When the injection superheat is greater than T3, the auxiliary circuit electronic expansion valve opens at a certain rate, generally about 2P / 20s;

[0108] Note: T1 is generally 1 to 3, T2 is generally 4 to 7, and T3 is generally 8 to 12;

[0109] ② When the auxiliary electronic expansion valve is turned on and the compressor is turned on for 5 minutes, once the exhaust superheat is detected to be greater than △T (monitoring reference threshold) for the first time, the auxiliary electronic expansion valve will exit the refrigerant deposition startup stage control and control according to the exhaust superheat or injection superheat;

[0110] When the exhaust gas superheat is greater than P1 (the first pressure threshold), the auxiliary circuit electronic expansion valve gradually opens wider in each adjustment cycle (the step size of each action generally does not exceed 2% of its maximum opening);

[0111] When P2 (second pressure threshold) ≤ exhaust superheat ≤ P1, the injection superheat control is carried out according to step ①;

[0112] When the exhaust superheat is less than P2, the auxiliary electronic expansion valve is gradually closed in each adjustment cycle (the step size of each action generally does not exceed 2% of its maximum opening);

[0113] Note: △T is generally 10-15; P1 is generally 30-37, and P2 is generally 12-18.

[0114] In summary, this embodiment provides a tailor-made solution for the intelligent control of the auxiliary electronic expansion valve. Its implementation can automatically adjust and optimize the refrigerant flow during the startup process, ensure the safe operation of the compressor, and avoid potential failures caused by refrigerant deposition. It not only improves the safety and stability of the refrigeration or heat pump system, but also effectively improves energy efficiency and application flexibility.

[0115] Example 7: Figure 7 As shown, based on Example 6, the exhaust superheat acquisition process provided by the embodiment of the present invention includes the following steps:

[0116] S2021: using the exhaust temperature sensor to monitor the actual temperature of the exhaust end of the compressor in real time; at the same time, the high pressure sensor monitors the high pressure value;

[0117] S2022: According to the known high pressure value, query the characteristic table of the refrigerant, and use the relationship between the saturated vapor pressure and the corresponding temperature of the refrigerant to calculate the saturated temperature corresponding to the pressure;

[0118] S2023: The exhaust superheat is obtained by subtracting the actual temperature from the saturation temperature to obtain the safety of the compressor exhaust state.

[0119] The working principle and beneficial effects of the above technical solution are as follows: First, the exhaust temperature sensor is used to monitor the actual temperature of the exhaust end of the compressor in real time; at the same time, the high-pressure sensor monitors the high-pressure value; secondly, according to the known high-pressure value, the characteristic table of the refrigerant is queried, and the saturated vapor pressure of the refrigerant and the corresponding temperature relationship are used to calculate the saturated temperature corresponding to the pressure; finally, the actual temperature is subtracted from the saturated temperature to obtain the exhaust superheat, and the safety of the compressor exhaust state is obtained. Step S2021 of the above scheme monitors the compressor exhaust temperature and high-pressure value in real time, and uses the exhaust temperature sensor to monitor the actual temperature of the compressor exhaust end and the system high-pressure value monitored by the high-pressure sensor in real time, providing basic data support for the calculation; the real-time performance indicates that the system can quickly respond to changes in the operation of the compressor and provide timely information for subsequent control decisions. Significance: By obtaining accurate temperature and pressure data, the system can grasp the working status of the compressor in real time, thereby establishing a solid foundation for subsequent steps; the real-time performance of data is a prerequisite for ensuring system safety, improving operating efficiency, and ensuring equipment stability. Step S2022 calculates the saturation temperature corresponding to the pressure. According to the collected high pressure value, the saturation temperature corresponding to the pressure is calculated by consulting the characteristic table of the refrigerant. The physical characteristics are combined with the change of the actual pressure to ensure the accuracy of the saturation temperature. This step also supports the use of different types of refrigerants, and has strong adaptability. Different characteristic tables can be selected according to the system to calculate the saturation temperature, which improves flexibility. Significance: The calculated saturation temperature provides a benchmark for judging the exhaust state of the compressor, helping the system to determine the current state of the refrigerant (gaseous or liquid); it is crucial to evaluate the safety of the equipment and avoid the occurrence of liquid hammer, and also provides necessary parameters for the subsequent calculation of the exhaust superheat. Step S2023 calculates the exhaust superheat. The exhaust superheat is obtained by calculating the difference between the actual exhaust temperature monitored in real time and the calculated saturation temperature; it can intuitively reflect the exhaust state of the compressor and help determine whether the current refrigerant is within the safe working range. Significance: The obtained exhaust superheat is directly related to the safety of the system and the normal operation of the compressor. Accurate exhaust superheat assessment can prevent damage to the compressor due to overheating, and also provide a basis for system operation monitoring and optimization; long-term monitoring of this parameter can also serve as an important basis for system debugging and optimization, thereby improving the working efficiency and life of the equipment.

[0120] In summary, in the process of obtaining the exhaust superheat, this embodiment not only effectively collects and analyzes the key operating parameters of the system, but also its clear process design ensures the rapid processing and feedback of complex technical information. Through accurate temperature and pressure data acquisition, scientific saturation temperature calculation and intuitive superheat evaluation, the operating safety of the compressor and the efficiency of system control are further improved, ensuring the reliability and stability of the refrigeration system. The technical design of this process is highly reasonable and creative, and can provide important guarantees for intelligent control in practical applications.

[0121] Example 8: Figure 8 As shown, based on Example 6, the process for obtaining the injection superheat provided by the embodiment of the present invention includes the following steps:

[0122] S2031: using the auxiliary output temperature sensor to monitor the temperature of the auxiliary output end in real time; at the same time, using the auxiliary input temperature sensor to monitor the temperature of the auxiliary input end;

[0123] S2032: By comparing the auxiliary outlet temperature and the auxiliary inlet temperature, the temperature difference, i.e., the injection superheat, is calculated, which indicates the temperature change from the auxiliary inlet end to the auxiliary outlet end after the refrigerant passes through the system, reflecting the superheat degree of the refrigerant;

[0124] S2033: Based on the result of the injection superheat, it is compared with the set threshold. If the calculated injection superheat exceeds the preset value, the automatic adjustment mechanism will be activated to adjust the opening of the auxiliary electronic expansion valve through instant feedback.

[0125] The working principle and beneficial effects of the above technical solution are as follows: the present embodiment first uses the auxiliary outlet temperature sensor to monitor the temperature of the auxiliary outlet in real time; at the same time, uses the auxiliary inlet temperature sensor to monitor the temperature of the auxiliary inlet; secondly, by comparing the auxiliary outlet temperature and the auxiliary inlet temperature, the temperature difference, i.e., the injection superheat, is calculated, which indicates the temperature change from the auxiliary inlet to the auxiliary outlet after the refrigerant passes through the system, reflecting the degree of overheating of the refrigerant; finally, based on the result of the injection superheat, it is compared with the set threshold value. If the calculated injection superheat exceeds the preset value, the automatic adjustment mechanism will be started to adjust the opening of the auxiliary electronic expansion valve through instant feedback. Step S2031 of the above scheme monitors the auxiliary outlet temperature and the auxiliary inlet temperature in real time, and uses the auxiliary outlet temperature sensor and the auxiliary inlet temperature sensor to monitor the temperature of the auxiliary outlet and the temperature of the auxiliary inlet in real time, respectively, to ensure that accurate temperature information is obtained; through real-time monitoring, the current state of the refrigerant can be quickly obtained and responded to, providing a reliable data basis for subsequent calculations. Significance: Accurate temperature data is crucial to understanding the entire refrigeration cycle, laying a solid foundation for the calculation of injection superheat, reflecting the actual performance of the refrigerant during operation, and helping to promptly identify potential problems and prevent failure risks. Step S2032 calculates the injection superheat, compares the auxiliary outlet temperature and auxiliary inlet temperature obtained by monitoring, and obtains the injection superheat; the calculation result directly reflects the degree of temperature rise of the refrigerant in the auxiliary circuit, indicating its degree of overheating, and can provide a reference for evaluating refrigeration efficiency and safety. Significance: The calculation of injection superheat allows the system to quantify the thermal state of the refrigerant, providing an intuitive standard to determine whether the refrigerant is in a reasonable working state; if the injection superheat is too high, it may affect the refrigeration effect and increase the risk of equipment damage. The calculation process is crucial to the maintenance of operational safety and system efficiency. Step S2033 compares the calculated injection superheat with the preset safety threshold and adjusts the electronic expansion valve, ensuring that the working state of the refrigerant is within the safe range; when the injection superheat exceeds the preset value, the system will start the automatic adjustment mechanism, adjust the opening of the auxiliary electronic expansion valve through instant feedback, optimize the refrigerant flow and pressure, and adjust the working state of the system. Significance: Through the automatic adjustment mechanism, it can respond quickly according to the real-time monitoring data during operation, effectively preventing accidents caused by overheating; the active control strategy not only improves the safety and operation stability of the system, but also greatly improves the overall energy efficiency utilization rate, providing a guarantee for the efficient and safe operation of the equipment.

[0126] In summary, in the process of obtaining the injection superheat, this embodiment combines real-time data acquisition, temperature difference calculation and intelligent adjustment mechanism to establish a complete and efficient control system. Through accurate data monitoring and calculation, it ensures that the equipment is within a reasonable working range, reduces the risk of failure, and improves operating efficiency, while providing strong technical support for future intelligent development.

[0127] Example 9: Fig. 9 As shown, based on Example 1, the process of unlocking the auxiliary circuit electronic expansion valve control program provided by the embodiment of the present invention includes the following steps:

[0128] S301: Comprehensively monitor the temperature and pressure of the compressor, including confirming whether the exhaust superheat of the compressor is within the safety threshold; use the flow sensor to monitor the refrigerant flow rate in real time. If the flow rate is stable and within the preset range, proceed to the next step;

[0129] S302: according to the real-time monitoring result and the opening adjustment strategy of the auxiliary electronic expansion valve, the opening setting parameters are obtained; the unlocking program is automatically executed to convert the auxiliary electronic expansion valve control program from the locked state to the unlocked state;

[0130] S303: After unlocking is completed, it automatically switches to the automatic control mode of the heat pump; the opening of the auxiliary electronic expansion valve will be automatically adjusted according to changes in pressure, temperature and demand.

[0131] The working principle and beneficial effects of the above technical solution are as follows: the present embodiment firstly comprehensively monitors the temperature and pressure of the compressor, including confirming whether the exhaust superheat of the compressor is within the safety threshold; uses a flow sensor to monitor the refrigerant flow rate in real time, and if the flow rate is stable and within the preset range, then proceeds to the next step; secondly, according to the real-time monitoring results, the opening adjustment strategy of the auxiliary electronic expansion valve obtains the opening setting parameters; automatically executes the unlocking program, and converts the auxiliary electronic expansion valve control program from the locked state to the unlocked state; finally, after the unlocking is completed, it automatically switches to the automatic control mode of the heat pump; the opening of the auxiliary electronic expansion valve will be automatically adjusted according to the changes in pressure, temperature and demand. Step S301 of the above scheme comprehensively monitors the temperature, pressure and refrigerant flow rate of the compressor. By comprehensively monitoring the temperature and pressure of the compressor, it can accurately identify whether it is within the safe working range, and at the same time confirm whether the exhaust superheat of the compressor is within the safety threshold; uses a flow sensor to obtain the refrigerant flow rate in real time, ensures that the flow rate is stable and within the preset range, and lays the foundation for the unlocking process of the system; ensures that all monitoring data meet the safety standards, so as to judge whether the conditions for unlocking are met. Significance: On the basis of ensuring the normal operation of the compressor and the flow of refrigerant, it provides important safety guarantees for subsequent unlocking operations, is the prerequisite for achieving stable operation, and plays a key role in avoiding equipment damage or performance degradation. Step S302 The execution of the opening adjustment strategy and unlocking program generates the optimal opening setting parameters of the auxiliary electronic expansion valve based on real-time monitoring data, combined with factors such as flow, pressure and temperature; optimizes the opening configuration through intelligent algorithms to adapt to current system requirements; after confirming that all conditions are met, the auxiliary electronic expansion valve control program is automatically changed from a locked state to an unlocked state to ensure that the system can be restored to a normal control state at the right time. Significance: Through intelligent adjustment and automatic unlocking, it ensures that the system can resume operation quickly and efficiently, reduces the need for human intervention, and improves the automation level of the heat pump; it not only improves the response speed of the system, but also optimizes the realization of operational efficiency, which is an important manifestation of intelligent management of modern heat pump systems. Step S303 completes unlocking and switches to automatic control mode. After unlocking, the system can automatically switch to the automatic control mode of the heat pump, so that the opening of the auxiliary electronic expansion valve can be dynamically adjusted according to the real-time pressure, temperature and system requirements; it can flexibly respond to changes in the external and internal environment, and improve the overall intelligence of the system operation. Significance: Automatically switching to the control mode of the heat pump enables the system to efficiently and continuously adapt to different operating conditions and load requirements, which helps to maintain the optimal operating efficiency and long-term stability of the heat pump; it provides the necessary foundation for the intelligent development of the heat pump system and promotes the realization of energy efficiency improvement and energy saving goals.

[0132] In summary, each step of the unlocking auxiliary electronic expansion valve control program of this embodiment ensures that the system resumes normal operation in a safe and stable state. Through the combination of real-time monitoring, intelligent decision-making and automatic control, not only the efficiency and safety of the heat pump system are improved, but also a solid foundation for future intelligent control systems is laid.

[0133] Example 10: Fig.10 As shown, based on Example 9, the acquisition process of the auxiliary circuit electronic expansion valve opening adjustment strategy provided by the embodiment of the present invention includes the following steps:

[0134] S3021: Collect data from multiple sensors, including compressor temperature, pressure, exhaust superheat, and refrigerant flow rate, clean the collected data, and remove abnormal values ​​and noise; determine the key variables that affect the opening setting, including ambient temperature, system pressure, exhaust superheat, and refrigerant flow rate;

[0135] S3022: Based on the key variables monitored in real time, set the objective function of maximizing cooling efficiency, minimizing energy consumption or minimizing exhaust superheat; use the acquired data and historical operation mode to predict demand and adjust the opening degree;

[0136] S3023: Generate specific control instructions based on the obtained opening setting parameters and send them to the auxiliary electronic expansion valve; after the opening adjustment is performed and the execution is obtained, feedback is provided to determine whether the setting has achieved the expected effect, thereby forming a closed-loop control.

[0137] The working principle and beneficial effects of the above technical solution are as follows: This embodiment first collects data from multiple sensors, including the temperature, pressure, exhaust superheat, and refrigerant flow rate of the compressor, cleans the collected data, and removes outliers and noise; determines the key variables that affect the opening setting, including ambient temperature, system pressure, exhaust superheat, and refrigerant flow rate; secondly, based on the key variables monitored in real time, sets the objective function of maximizing refrigeration efficiency, minimizing energy consumption, or minimizing exhaust superheat; uses the acquired data and historical operating modes to predict demand and adjust the opening; finally, based on the obtained opening setting parameters, generates specific control instructions and sends them to the auxiliary electronic expansion valve; after executing the opening adjustment and obtaining the execution, feedback is provided to determine whether the setting has achieved the expected effect, thereby forming a closed-loop control. Step S3021 of the above scheme is data collection and cleaning. By collecting data from different sensors, including compressor temperature, pressure, exhaust superheat and refrigerant flow rate, the system operation status can be fully monitored. Outliers and noise are eliminated to ensure the accuracy and reliability of data, laying a foundation for data analysis and decision-making. By analyzing and comparing different variables, the key variables that have the greatest impact on the opening setting of the electronic expansion valve are identified, providing an important basis for subsequent optimization. Significance: It ensures that the information obtained by the system is reliable, thereby improving the effectiveness of the subsequent decision-making process. Accurate data support is a prerequisite for achieving efficient control and can help the system maintain stable performance under rapidly changing operating conditions. Step S3022 is objective function setting and demand forecasting. The objective function of maximizing refrigeration efficiency, minimizing energy consumption or minimizing exhaust superheat is set to ensure that the goal of opening adjustment is clear and measurable. Combine real-time monitoring data and historical operating modes to predict the cooling demand of the system, thereby providing forward-looking data support for opening adjustment. According to the changing system requirements and conditions, the opening setting is flexibly adjusted to make it more suitable for the current operating status. Significance: The intelligent management capability of the system is improved. The prediction and analysis based on data can more effectively adapt to the changing operating environment, reduce energy waste and energy efficiency loss; the clear objective function makes the formation of subsequent control strategies more scientific. Step S3023 control command generation and closed-loop feedback, based on the opening setting parameters obtained by optimization calculation, generate specific control instructions and pass them to the auxiliary electronic expansion valve to ensure the accuracy and timeliness of execution; after the opening is adjusted, the actual effect is fed back by the sensor, and the actual opening adjustment is compared with the expected effect to form a closed-loop control; by analyzing the feedback results, the subsequent opening settings are adjusted in real time to optimize the control process. Significance: By implementing closed-loop control, it is ensured that the system can be continuously optimized in actual operation, and the opening settings can be flexibly adjusted according to feedback information, so as to maximize the effectiveness of the system; the adaptability and efficiency of the overall control strategy are improved, ensuring that the heat pump system can maintain the established performance in long-term operation.

[0138] In summary, the process of acquiring the opening adjustment strategy of the auxiliary electronic expansion valve in this embodiment realizes a complete closed loop from data collection to decision-making execution, strengthens the basic role of data, and promotes the improvement of accuracy and reliability; clarifies the optimization goal and provides theoretical support for dynamic adjustment; implements a closed-loop feedback mechanism to achieve self-optimization and continuous improvement of the system. It not only improves the efficiency of system operation, but also lays a solid foundation for possible system expansion and upgrading in the future, and is an important means to realize the intelligence and efficiency of heat pumps.

[0139] Example 11: Fig.11 As shown, on the basis of Example 1 to Example 10, the heat pump system provided by the embodiment of the present invention comprises: a compressor 1, a low pressure sensor 2, a return air temperature sensor 3, an auxiliary circuit electronic expansion valve 4, a fin-tube heat exchanger 5, an ambient temperature sensor 6, a water side heat exchanger 7, a main circuit electronic expansion valve 8, an economizer 9, an auxiliary outlet temperature sensor 10, an auxiliary inlet temperature sensor 11, a four-way valve 12, a high pressure sensor 13, and an exhaust temperature sensor 14;

[0140] Among them, the compressor 1 is connected to the S end of the four-way valve 12 through the pipeline, the low-pressure sensor 2 and the return air temperature sensor 3, the ambient temperature sensor 6 is installed at the bottom of the fin-tube heat exchanger 5, one end of the fin-tube heat exchanger 5 is connected to the E end of the four-way valve 12, the other end of the fin-tube heat exchanger 5 is connected to the main electronic expansion valve 8 and the economizer 9, the economizer 9 is connected to the auxiliary outlet temperature sensor 10 and the auxiliary inlet temperature sensor 11, the auxiliary inlet temperature sensor 11 is connected to the auxiliary electronic expansion valve 4, the auxiliary outlet temperature sensor 10 is connected to the compressor 1, the C end of the four-way valve 12 is connected to the water side heat exchanger 7, the water side heat exchanger 7 is connected to the economizer 9, and the compressor 1 is connected to the D end of the four-way valve 12 through the exhaust temperature sensor 14 and the high-pressure sensor 13.

[0141] The working principle and beneficial effects of the above technical solution are as follows: after starting, the compressor 1 compresses the low-pressure refrigerant gas to increase the pressure and temperature of the refrigerant. The refrigerant monitors its status through the exhaust temperature sensor 14 and the high-pressure sensor 13 to ensure that it works within a safe range; the four-way valve 12 is responsible for switching between the heating mode and the cooling mode, and guiding the flow of the refrigerant as needed; its S end receives signals from the low-pressure sensor 2 and the return air temperature sensor 3 to ensure that the refrigerant flow required by the compressor is reasonable. When the refrigerant flows through the fin-tube heat exchanger 5, the ambient temperature sensor 6 monitors the ambient temperature, and the refrigerant absorbs or releases heat here, depending on the current working mode. The fin-tube heat exchanger 5 realizes efficient heat exchange to provide the required heat to the target environment. After passing through the fin-tube heat exchanger, the refrigerant flows into the main electronic expansion valve 8, and enters the economizer 9 after decompression. The design of the economizer 9 improves the efficiency of the system and reduces power consumption. The auxiliary electronic expansion valve 4 ensures the flow control of the auxiliary circuit and optimizes the use of the refrigerant. The water-side heat exchanger 7 is connected to the C end of the four-way valve and is responsible for heat exchange with the water system (such as heating or cooling) to achieve heat transfer between the refrigerant and water. In the entire system, the auxiliary outlet temperature sensor 10 and the auxiliary inlet temperature sensor 11 respectively monitor the inlet and outlet temperatures of the heat medium to ensure the operating efficiency of the system and provide information for regulating the closed-loop feedback.

[0142] This embodiment can effectively convert low-level heat (such as heat in ambient air, ground or water) into high-level heat energy for heating, completing the effective transfer of heat; the four-way valve can adjust the system's switching between heating and cooling, making the heat pump system multifunctional and adaptable to different user needs; various sensors monitor temperature and pressure in real time to ensure the safety and stability of the system in various working states, and can correct any abnormalities in a timely manner; using renewable resources (such as air, ground) as heat sources helps reduce the use of fossil fuels and achieve environmental protection and energy conservation goals. Significance: The design and working principle of the heat pump system make it more efficient in energy use than traditional heating and cooling systems, reducing energy consumption and thus reducing carbon emissions; flexibility enables it to work in different seasons and different environmental conditions to meet the different needs of users; the energy-saving effect makes its long-term operating cost relatively low, improving economic benefits; real-time monitoring and dynamic adjustment ensure the stability of the system and reduce downtime caused by equipment failure or performance degradation.

[0143] In summary, this embodiment effectively integrates various components and sensors to achieve excellent performance in efficient heat exchange and conversion while also having flexibility and stability, thereby providing users with an economical and environmentally friendly solution.

[0144] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention belong to the scope of equivalent technologies of the present invention, the present invention is also intended to include these modifications and variations.

Claims

1. A rapid oil return method for a heat pump system, characterized in that: The following steps are involved: Before starting the compressor, obtain the ambient temperature and downtime duration, and determine whether there is refrigerant deposition based on the ambient temperature and downtime duration; If there is refrigerant deposition, the auxiliary circuit electronic expansion valve control program is started; if there is no refrigerant deposition, the heat pump is started according to the normal program; Start the auxiliary electronic expansion valve control program, judge the exhaust superheat and compare it with the monitoring reference threshold, and confirm whether to control according to the exhaust superheat or injection superheat; at the same time, compare the exhaust superheat with multiple pressure thresholds, and compare the injection superheat with multiple temperature thresholds to confirm the opening of the auxiliary electronic expansion valve; Confirm that the compressor temperature, pressure and exhaust superheat are within the normal range, confirm that the refrigerant flow rate is stable, unlock the auxiliary electronic expansion valve control program, exit the fast oil return mode, and return to the automatic control mode of the heat pump.

2. The rapid oil return method of the heat pump system according to claim 1, characterized in that: The process of judging whether there is refrigerant deposition based on the ambient temperature and downtime duration includes the following steps: The current ambient temperature of the compressor area is collected through the ambient temperature sensor device, and the downtime of the compressor is recorded and monitored in real time from the heat pump system. The acquired ambient temperature and downtime duration are integrated to form a data set. Construct a refrigerant deposition judgment model, train it through the input of multi-dimensional features of ambient temperature and downtime, and identify the potential pattern of refrigerant deposition; Output the probability value of the existence of refrigerant deposition; when the probability value exceeds the judgment threshold, it is considered that refrigerant deposition exists; Depending on whether there is refrigerant deposition, it is determined whether to start the auxiliary electronic expansion valve control program or start the heat pump according to the normal program; when there is refrigerant deposition, the auxiliary electronic expansion valve control program is started, and the heat pump started by the normal program is in a stopped state.

3. The rapid oil return method of the heat pump system according to claim 2, characterized in that: The process of forming a data set includes the following steps: A short-time polling strategy is used to obtain temperature readings from the temperature sensor, and multiple temperature measurement data are obtained within a time interval to form a temperature fluctuation map; a timer is used to record the start and stop time of the compressor in real time, automatically sense the state change of the compressor, and start timing when the compressor is detected to be stopped. The record includes the continuous shutdown time of the compressor and the total shutdown time; The collected ambient temperature and downtime are integrated and normalized in real time to form a multi-dimensional data set; feature extraction is performed on the temperature and time data to generate additional features, including the temperature change rate, to show the rapid change of temperature, downtime mode, and identify which mode is related to refrigerant deposition; The integrated and normalized data sets are stored in the database; at the same time, version control of the data sets is implemented, and each version of data is saved for different operation cycles.

4. The rapid oil return method of the heat pump system according to claim 2, characterized in that: The process of building a refrigerant deposition judgment model includes the following steps: From the data set, extract the characteristics of factors that affect the deposition of added refrigerant, including temperature change rate, cumulative downtime and stability index; divide the data set into training set, validation set and test set; The random forest was applied to the training set to train the refrigerant deposition judgment model, and the cross-validation method was used in the optimization process to adjust the hyperparameters; The performance of the trained refrigerant deposition judgment model is evaluated using the validation set. The evaluation indicators include: accuracy, precision and recall rate; the probability value of refrigerant deposition is output; the verified refrigerant deposition judgment model is embedded in the real-time monitoring system, set to automatic operation mode, and receive real-time ambient temperature and downtime duration data for analysis.

5. The rapid oil return method of the heat pump system according to claim 2, characterized in that: The setting process of the auxiliary electronic expansion valve control program includes the following steps: Design a multi-level control program that includes data analysis, decision execution, and operation feedback. The first level is responsible for real-time data collection and status evaluation, the second level is responsible for judgment logic and control decision-making, and the last level is responsible for execution and feedback; The trained refrigerant deposition judgment model is used to analyze the ambient temperature and downtime duration, and the probability value of refrigerant deposition is output. When the probability value exceeds the set threshold, the flag signal of refrigerant deposition is immediately triggered. After the refrigerant deposition is judged to exist, the working mode will be switched immediately according to the pre-set priority rules, and the opening degree of the auxiliary electronic expansion valve will be adjusted to respond to the demand for refrigerant flow. At the same time, the heat pump stop command is automatically sent to cut off the heat pump startup program. After obtaining a signal of the presence of refrigerant deposition, a stop signal is sent to the heat pump control circuit through a programmable logic controller; A status feedback loop is established to detect the output status of the heat pump in real time through sensors to ensure that the stop command is effectively executed; if the feedback signal shows that the heat pump is still in the starting state, the fault handling mechanism will be activated, the stop command will be resent and fault troubleshooting will be performed.

6. The rapid oil return method of a heat pump system according to claim 1, characterized in that: The process of controlling according to exhaust superheat or injection superheat includes the following steps: The auxiliary circuit electronic expansion valve opens to the preset initial opening and maintains the state; After the initial opening is set, real-time monitoring and adjustment are performed for the exhaust superheat. According to different superheat ranges, the opening of the auxiliary electronic expansion valve is adjusted according to the set conditions; When the compressor is turned on and the exhaust superheat is detected for the first time to exceed the set monitoring reference threshold, the auxiliary electronic expansion valve exits the control mode of the refrigerant deposition startup phase and enters the exhaust or injection superheat regulation.

7. The rapid oil return method of a heat pump system according to claim 6, characterized in that: The process of obtaining the exhaust superheat includes the following steps: The exhaust temperature sensor is used to monitor the actual temperature of the compressor exhaust end in real time; at the same time, the high pressure sensor monitors the high pressure value; According to the known high pressure value, query the refrigerant characteristic table, and use the relationship between the saturated vapor pressure and the corresponding temperature of the refrigerant to calculate the saturation temperature corresponding to the pressure; The exhaust superheat is obtained by subtracting the actual temperature from the saturation temperature, thereby determining the safety of the compressor exhaust state.

8. The rapid oil return method of a heat pump system according to claim 6, characterized in that: The process of obtaining the injection superheat includes the following steps: Use the auxiliary output temperature sensor to monitor the temperature of the auxiliary output end in real time; at the same time, use the auxiliary input temperature sensor to monitor the temperature of the auxiliary input end; By comparing the auxiliary outlet temperature and the auxiliary inlet temperature, the temperature difference, i.e. the injection superheat, is calculated, which indicates the temperature change from the auxiliary inlet end to the auxiliary outlet end after the refrigerant passes through the system, reflecting the superheat degree of the refrigerant; Based on the result of the injection superheat, it is compared with the set threshold. If the calculated injection superheat exceeds the preset value, the automatic adjustment mechanism will be activated to adjust the opening of the auxiliary electronic expansion valve through instant feedback.

9. The rapid oil return method of a heat pump system according to claim 1, characterized in that: The process of unlocking the auxiliary electronic expansion valve control program includes the following steps: Comprehensively monitor the temperature and pressure of the compressor, including confirming whether the compressor's exhaust superheat is within the safety threshold; use a flow sensor to monitor the refrigerant flow rate in real time. If the flow rate is stable and within the preset range, proceed to the next step; According to the real-time monitoring results, the auxiliary electronic expansion valve opening adjustment strategy obtains the opening setting parameters; the unlocking program is automatically executed to convert the auxiliary electronic expansion valve control program from the locked state to the unlocked state; After unlocking is completed, it will automatically switch to the automatic control mode of the heat pump; the opening of the auxiliary electronic expansion valve will be automatically adjusted according to changes in pressure, temperature and demand.

10. The rapid oil return method of a heat pump system according to claim 9, characterized in that: The process of obtaining the auxiliary circuit electronic expansion valve opening adjustment strategy includes the following steps: Collect data from multiple sensors, including compressor temperature, pressure, exhaust superheat, and refrigerant flow rate, clean the collected data, and remove outliers and noise; determine the key variables that affect the opening setting, including ambient temperature, system pressure, exhaust superheat, and refrigerant flow rate; Based on real-time monitoring of key variables, set the objective function of maximizing refrigeration efficiency, minimizing energy consumption or minimizing exhaust superheat; use the acquired data and historical operating patterns to predict demand and adjust the opening degree; According to the obtained opening setting parameters, a specific control instruction is generated and sent to the auxiliary electronic expansion valve; after the opening adjustment is performed and the execution is obtained, feedback is given to see whether the setting has achieved the expected effect, forming a closed-loop control.

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