Refrigerant leakage control method of heat pump system

Abstract

The invention relates to the technical field of heat pump systems, in particular to a refrigerant leakage control method of a heat pump system, and aims to solve the problem of how to balance safety and use experience under the condition of refrigerant leakage. Therefore, according to the refrigerant leakage control method of the heat pump system, the refrigerant leakage mode can be accurately recognized through the concentration information and / or the pressure information, on one hand, unnecessary shutdown operation on the power load under the condition of slight leakage can be effectively avoided, the user experience is improved, and the user experience is improved. The possibility that a user bypasses a safety protection mechanism manually can be reduced, so that the operation reliability of the heat pump system is improved, and on the other hand, the power load can be cut off in time under the condition that the refrigerant leaks seriously, so that the safety is improved.

Description

Technical Field

[0001] This invention relates to the field of heat pump systems, and specifically provides a method for controlling refrigerant leakage in heat pump systems. Background Technology

[0002] With increasing global awareness of environmental protection, the environmental performance of refrigerants is receiving more and more attention. Currently, refrigerants are gradually shifting from traditional refrigerants such as R22 and R410A to more environmentally friendly ones like R32 and R290. However, according to flammability ratings, R32 and R290 are classified as flammable and explosive, posing a fire hazard when these refrigerants leak and reach a certain concentration. Therefore, when a refrigerant leak occurs, a strategy of forcibly shutting down the heat pump system is usually adopted. While this method ensures safety, it has significant shortcomings: in cases of minor refrigerant leaks without any safety hazards, forcibly stopping the power loads in the heat pump system, such as the compressor, electric auxiliary heater, and water pump, not only degrades the user experience and leads users to misjudge equipment malfunctions, but may also encourage some users to bypass the safety protection mechanism and continue operation, thus increasing potential risks.

[0003] Therefore, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0004] To address at least one problem in the prior art, namely, how to balance safety and user experience in the event of refrigerant leakage, this application provides a refrigerant leakage control method for a heat pump system, the refrigerant leakage control method comprising:

[0005] Obtain current concentration information and / or current pressure information; the current concentration information includes at least one of the current refrigerant concentration and the current refrigerant concentration change rate, and the current pressure information includes at least one of the current exhaust and intake pressure difference, the current exhaust pressure change rate, and the current intake pressure change rate;

[0006] Based on the current concentration information and / or the current pressure information, a refrigerant leakage mode is determined; the refrigerant leakage mode includes a warning mode and an emergency mode;

[0007] Based on the determined refrigerant leakage pattern, the power load in the heat pump system is selectively controlled to stop operating.

[0008] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "determining the refrigerant leakage mode based on the concentration information and / or the pressure information" specifically includes:

[0009] When the first preset condition is met, the refrigerant leakage mode is determined to be the emergency mode;

[0010] When the second preset condition is met, the refrigerant leakage mode is determined to be the warning mode:

[0011] The first preset condition includes at least one of the following conditions:

[0012] The current refrigerant concentration is greater than the first concentration threshold;

[0013] The current refrigerant concentration change rate is greater than the first concentration change rate threshold, and the larger of the absolute values ​​of the current exhaust pressure change rate and the current intake pressure change rate is greater than the pressure change rate threshold.

[0014] The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold, and the pressure difference is less than or equal to the pressure difference threshold;

[0015] The second preset condition includes at least one of the following conditions:

[0016] The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold;

[0017] The larger of the absolute values ​​of the current exhaust pressure change rate and the current intake pressure change rate is greater than the pressure change rate threshold.

[0018] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "selectively controlling the power load in the heat pump system to stop working according to the determined refrigerant leakage mode" specifically includes:

[0019] When the refrigerant leakage mode is determined to be the emergency mode, the power load is controlled to stop working.

[0020] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "controlling the power load to stop working" includes, before, after, or simultaneously with, the following:

[0021] Control the ventilation load in the heat pump system to operate at maximum ventilation capacity; and / or

[0022] Issue the first alert.

[0023] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "determining, based on the refrigerant leakage mode, to selectively control the power load in the heat pump system to stop working" specifically includes:

[0024] When the refrigerant leakage mode is determined to be the warning mode, the ventilation load in the heat pump system is controlled to operate at the minimum ventilation capacity.

[0025] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "controlling the ventilation load in the heat pump system to operate at minimum ventilation capacity" includes, before, after, or simultaneously with, the following steps:

[0026] Reduce the operating frequency of the power load; and / or

[0027] Issue a second alert.

[0028] In the preferred embodiment of the above-mentioned refrigerant leakage control method, after the step of "controlling the ventilation load in the heat pump system to operate at the minimum ventilation capacity", the method further includes:

[0029] After a set time period, acquire the current concentration and pressure information;

[0030] Based on the current concentration and pressure information, determine whether the heat pump system meets the conditions for resuming normal operation.

[0031] When the conditions for restoring the normal operating mode are met, the power load is controlled to return to the operating state before entering the warning mode;

[0032] The conditions for restoring the normal operating mode include the following:

[0033] The current refrigerant concentration is less than or equal to the refrigerant concentration at the previous moment;

[0034] The absolute value of the current rate of change of exhaust pressure is less than or equal to the absolute value of the rate of change of exhaust pressure at the previous moment.

[0035] The absolute value of the current rate of change of inspiratory pressure is less than or equal to the absolute value of the rate of change of inspiratory pressure at the previous moment.

[0036] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the refrigerant leakage control method further includes:

[0037] Based on the current concentration information and / or current pressure information, determine whether the heat pump system meets the first preset condition;

[0038] When the first preset condition is met, the power load is controlled to stop working.

[0039] In the preferred embodiment of the above-mentioned refrigerant leakage control method, after the step of "controlling the power load to stop working", the method further includes:

[0040] Every second set time interval, the current concentration information is obtained, and the current refrigerant concentration and the rate of change of current refrigerant concentration at M sampling points are obtained;

[0041] Based on the current refrigerant concentration and the rate of change of the current refrigerant concentration at M sampling points, determine whether N consecutive sampling points among the M sampling points simultaneously meet the third preset condition.

[0042] When the N consecutive sampling points simultaneously meet the third preset condition, the heat pump system meets the condition for relieving the refrigerant leakage mode.

[0043] Control the power load to restart operation;

[0044] The third preset condition includes the following conditions:

[0045] The current refrigerant concentration is less than or equal to the third concentration threshold;

[0046] The absolute value of the current refrigerant concentration change rate is less than the second concentration change rate threshold;

[0047] Wherein, the third concentration threshold is less than the second concentration threshold, the second concentration change rate threshold is less than the first concentration change rate threshold, and M>N≥2.

[0048] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "obtaining current concentration information every second set time" is followed by:

[0049] Control the ventilation load in the heat pump system to operate for a third set time;

[0050] During the third set time period, the current concentration information is acquired every second set time period.

[0051] The third set time is greater than the second set time.

[0052] In the preferred embodiment of the above-mentioned refrigerant leakage control method, the step of "controlling the power load to restart operation" further includes:

[0053] The heat pump system is controlled to enter a reset mode;

[0054] Determine whether the heat pump system meets the reset conditions;

[0055] When the reset condition is met, the power load is controlled to restart operation;

[0056] The reset condition includes at least one of the following conditions:

[0057] The heat pump system remains in the reset mode for more than a fourth preset time.

[0058] A reset command has been received.

[0059] Those skilled in the art will understand that the refrigerant leakage control method for the heat pump system of this application can accurately identify refrigerant leakage modes through concentration information and / or pressure information. On the one hand, it can effectively avoid unnecessary shutdown operations on the power load in the case of minor leakage, which not only improves the user experience, but also reduces the possibility of users circumventing the safety protection mechanism, thereby improving the operational reliability of the heat pump system. On the other hand, it can also cut off the power load in time in the case of serious refrigerant leakage, thereby improving safety.

[0060] Furthermore, by setting a multi-trigger mechanism with first and second preset conditions, false positives or false negatives can be effectively prevented, thereby improving the comprehensiveness and accuracy of leak detection.

[0061] Furthermore, by controlling the power load to stop working when the refrigerant leakage mode is in emergency mode, it is possible to prevent continuous refrigerant leakage and accumulation, thereby improving safety.

[0062] Furthermore, by controlling the ventilation load to operate at maximum ventilation capacity before, after, or simultaneously with the control of the power load ceasing operation, the diffusion and dilution of leaked refrigerant can be effectively promoted. In addition, by issuing an initial alarm before, after, or simultaneously with the control of the power load ceasing operation, manual intervention can be facilitated, improving safety and reliability.

[0063] Furthermore, when the refrigerant leak mode is in the warning mode, by controlling the ventilation load to operate at the minimum ventilation capacity, the leaked refrigerant can be diluted to prevent accumulation, and the unnecessary shutdown operation of the power load can be effectively avoided in the case of minor leaks.

[0064] Furthermore, by reducing the operating frequency of the power load before, after, or simultaneously with the ventilation load operating at minimum ventilation capacity, unnecessary shutdowns of the power load due to minor leaks can be effectively avoided, reducing the possibility of users circumventing safety protection mechanisms and thus improving the operational reliability of the heat pump system. In addition, by issuing a second alarm when the ventilation load operates at minimum ventilation capacity, manual intervention can be encouraged, further enhancing safety and reliability.

[0065] Furthermore, after the ventilation load operates at the minimum ventilation capacity, the current concentration and pressure information are continuously acquired. When the refrigerant concentration and pressure change rate are both less than or equal to the data of the previous moment, it indicates that the refrigerant leakage has no signs of continuous deterioration or drastic fluctuation. At this point, it is determined that the conditions for restoring the normal operation mode are met, and the power load is restored to the original operating state. This can minimize the interference with the user's normal use while ensuring safety and improving the user experience.

[0066] Furthermore, after the power load stops working, concentration information is acquired every second set time to form concentration data for M consecutive sampling points. If the concentration data of N consecutive sampling points in the M sampling points all meet the third preset condition, it is ensured that the residual amount of refrigerant in the environment has been continuously and stably kept below the safe range. This effectively eliminates interference factors such as temporary decrease in concentration caused by short-term fluctuations or local diffusion, and provides more solid and reliable data support for safely exiting the refrigerant leakage mode. Attached Figure Description

[0067] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0068] Figure 1 This is a flowchart of the refrigerant leakage control method for the heat pump system of this application;

[0069] Figure 2 This is a logic diagram of a possible implementation of the refrigerant leakage control method for the heat pump system of this application. Detailed Implementation

[0070] Preferred embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application.

[0071] Combination Figure 1-2 The refrigerant leakage control method for the heat pump system of this application is described.

[0072] like Figure 1 As shown, the refrigerant leakage control method for the heat pump system of this application includes:

[0073] S101. Obtain current concentration information and / or current pressure information. The current concentration information includes either the current refrigerant concentration or the current refrigerant concentration change rate. The current pressure information includes either the current pressure difference between exhaust and intake, the current exhaust pressure change rate, or the current intake pressure change rate.

[0074] For example, concentration sensors can be installed within the heat pump system, indoors, or other areas where refrigerant easily accumulates to acquire current concentration information. When the current concentration information is the current refrigerant concentration, the concentration sensor obtains the current refrigerant concentration. When the current concentration information is the rate of change of the current refrigerant concentration, the rate of change is obtained by calculating the difference between the current refrigerant concentration and the previous refrigerant concentration, combined with the sampling time interval. Pressure sensors can be installed on the high-pressure and low-pressure sides of the heat pump system compressor to acquire current pressure information. When the current pressure information is the pressure difference between the current exhaust and intake gases, the two pressure sensors acquire the current exhaust pressure and the current intake pressure respectively, and calculate the pressure difference between the current exhaust pressure and the current intake pressure. When the current pressure information is the rate of change of the current exhaust pressure and the rate of change of the current intake pressure, the rates of change of the current exhaust pressure and the current intake pressure are calculated by combining the difference between the current pressure and the previous pressure with the sampling time interval.

[0075] The concentration sensor can be an NDIR sensor, a semiconductor sensor, or a catalytic combustion sensor. In addition to obtaining pressure information through a pressure sensor, current pressure information can also be indirectly obtained by combining exhaust temperature and compressor current. The principle is as follows: changes in current directly reflect changes in system load and compression ratio; that is, when the current increases, the compression ratio increases, exhaust pressure rises, and intake pressure decreases; when the current decreases, the compression ratio decreases, exhaust pressure decreases, and intake pressure rises. Simultaneously, changes in exhaust temperature and exhaust pressure are positively correlated; that is, an increase in exhaust temperature indicates an increase in exhaust pressure, and vice versa. In actual operation, when the current decreases and the exhaust temperature decreases simultaneously, it indicates that the system is in a low-load, low-compression-ratio state; conversely, if the current and exhaust temperature increase simultaneously, it indicates that the system is in a high-load, high-compression-ratio condition.

[0076] S102. Determine the refrigerant leakage mode based on the current concentration information and / or current pressure information. The refrigerant leakage mode includes a warning mode and an emergency mode. For example, after obtaining at least one parameter among the current refrigerant concentration, current refrigerant concentration change rate, current exhaust pressure change rate, and current intake pressure change rate, if the parameter value is relatively large, it indicates a serious refrigerant leak, and the refrigerant leakage mode can be determined as the emergency mode; if the parameter value is relatively small, it indicates a minor refrigerant leak, and the refrigerant leakage mode can be determined as the warning mode.

[0077] S103. Based on the determined refrigerant leakage mode, selectively control the power load in the heat pump system to stop operating. For example, when the refrigerant leakage mode is determined to be an emergency mode, control the power load to stop operating. When the refrigerant leakage mode is determined to be a warning mode, since the refrigerant leakage is minor, the load can be controlled to continue operating.

[0078] Through the concentration information and / or pressure information, the present application can accurately identify the refrigerant leakage mode. On the one hand, it can effectively avoid unnecessary shutdown operations on the power load in the case of slight leakage, which not only improves the user experience but also reduces the possibility of users bypassing the safety protection mechanism artificially, thereby improving the operation reliability of the heat pump system. On the other hand, it can also cut off the power load in time in the case of serious refrigerant leakage, improving safety.

[0079] The following introduces the preferred implementation manners of the refrigerant leakage control method for the heat pump system of the present application. Here, the current refrigerant concentration is C, and the current change rate of the refrigerant concentration is R c , the current discharge pressure is P1, the current suction pressure is P2, the pressure difference is ΔP, and the current change rate of the discharge pressure is R P1 , the current change rate of the suction pressure is R P2 .

[0080] In one implementation manner, the step of "determining the refrigerant leakage mode according to the concentration information and / or the pressure information" specifically includes:

[0081] When the second preset condition is satisfied, determine that the refrigerant leakage mode is the warning mode:

[0082] The second preset condition includes at least one of the following conditions:

[0083] The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold;

[0084] The larger value of the absolute value of the current change rate of the discharge pressure and the absolute value of the current change rate of the suction pressure is greater than the pressure change rate threshold.

[0085] For example, taking the current concentration information as the condition for determining the refrigerant leakage mode, the current concentration information is the current refrigerant concentration, and the first concentration threshold C 10 is 1500 ppm, and the second concentration threshold C 20 is 600 ppm for illustration. After obtaining the current refrigerant concentration C, compare the current refrigerant concentration C with the first concentration threshold C 10 and the second concentration threshold C 20 . When 600 ppm < C ≤ 1500 ppm, it indicates that the refrigerant is slightly leaked and the situation is relatively mild. Therefore, when 600 ppm < C ≤ 1500 ppm, determine that the refrigerant leakage mode is the warning mode, indicating that the refrigerant state needs to be concerned but no emergency treatment is required. When C ≤ 600 ppm, it indicates that the refrigerant content in the current environment is within the safe range, and the heat pump system is not in the refrigerant leakage mode.

[0086] Another example is given. Taking the current pressure information as the condition for determining the refrigerant leakage mode, the current pressure information is the current exhaust pressure change rate and the current suction pressure change rate, and the pressure change rate threshold R P0 is illustrated with 5 KPa / s. Obtaining the current exhaust pressure change rate R P1 and the current suction pressure change rate R P2 After that, compare the absolute value of the current exhaust pressure change rate R P1 and the absolute value of the current suction pressure change rate R P2 After obtaining the larger value of the two, compare the larger value with the pressure change rate threshold R P0 When max(|R P1 |, |R P2 |) > 5 KPa / s, it indicates that the pressure fluctuation is obvious, and the refrigerant leakage mode can be determined as the warning mode. When max(|R P1 |, |R P2 |) ≤ 5 KPa / s, it indicates that the system pressure is stable, and it can be determined as a safe operating condition without leakage risk, and the heat pump system is not in the refrigerant leakage mode.

[0087] Another example is given. Taking the current concentration information and the current pressure information simultaneously as the condition for determining the refrigerant leakage mode, the current concentration information is the current refrigerant concentration, and the current pressure information includes the current exhaust pressure change rate and the current suction pressure change rate. The first concentration threshold C 10 is 1500 ppm, the second concentration threshold C 20 is 600 ppm, and the pressure change rate threshold R P0 is illustrated with 5 KPa / s. Obtaining the current refrigerant concentration C, the current exhaust pressure change rate R P1 and the current suction pressure change rate R P2 After that, compare the absolute value of the current exhaust pressure change rate R P1 and the absolute value of the current suction pressure change rate R P2 After obtaining the larger value of the two, compare the larger value with the pressure change rate threshold R P0 and compare the current refrigerant concentration C with the first concentration threshold C 10 and the second concentration threshold C 20 When 600 PPm < C ≤ 1500 ppm and max(|R P1 |, |R P2 |) > 5 KPa / s, it indicates that the refrigerant has a slight leakage, and the refrigerant leakage mode can be determined as the warning mode. When max(|R P1 |, |R P2 |) ≤ 5 KPa / s, or C > 1500 ppm, or C ≤ 600 ppm, the refrigerant leakage mode does not meet the second preset condition of the warning mode.

[0088] In one implementation, the step of "determining the refrigerant leakage mode based on the concentration information and / or the pressure information" specifically includes:

[0089] When the first preset condition is met, the refrigerant leakage mode is set to emergency mode;

[0090] The first precondition includes at least one of the following conditions:

[0091] The current refrigerant concentration is greater than the first concentration threshold;

[0092] The current refrigerant concentration change rate is greater than the first concentration change rate threshold, and the larger of the absolute values ​​of the current exhaust pressure change rate and the current intake pressure change rate is greater than the pressure change rate threshold.

[0093] The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold, and the pressure difference is less than or equal to the pressure difference threshold;

[0094] It should be noted that when the current refrigerant concentration exceeds the first concentration threshold, it indicates that the refrigerant concentration has exceeded the absolute danger threshold. At this point, regardless of the values ​​of pressure parameters or other concentration parameters, the heat pump system has reached an unacceptable risk threshold. This single-parameter judgment logic is based on the fail-safe principle and must unconditionally trigger the emergency leak mode. Other conditions are based on both concentration and pressure parameters. The combination of concentration and pressure parameters can significantly improve the accuracy and reliability of refrigerant leak identification. The concentration parameter directly reflects the leak intensity, providing intuitive quantitative data; the pressure parameter captures dynamic changes in the system, generating indirect leak trend signals. The combination of the two can overcome the limitations of a single parameter and effectively suppress false alarms caused by sensor aging, dead zone interference, and short-term fluctuations, thereby more accurately and stably identifying real leak events under complex operating conditions and comprehensively improving robustness.

[0095] It should also be noted that this application does not impose any restrictions on the magnitude of the first concentration threshold, the second concentration threshold, the concentration change rate threshold, and the differential pressure threshold, as long as they can reflect refrigerant leakage. For example, the first concentration threshold may be in the range of 1500-2000 ppm; and / or, the second concentration threshold may be in the range of 600-1200 ppm; and / or, the first concentration change rate threshold may be greater than or equal to 20 ppm / s; and / or, the differential pressure threshold may be in the range of 200-300 kPa, with a differential pressure less than this range indicating an abnormal differential pressure; and / or, the pressure change rate threshold may be greater than or equal to 5 kPa / s, with the absolute value of the exhaust pressure change rate or the absolute value of the intake pressure change rate greater than this value indicating an exhaust or intake abnormality.

[0096] For example, taking the current concentration information as the condition for determining the refrigerant leakage mode, the current concentration information is the current refrigerant concentration, and the first concentration threshold C 10 is 1500 ppm, and the second concentration threshold C 20 is 600 ppm for illustration. After obtaining the current refrigerant concentration C, compare the current refrigerant concentration C with the first concentration threshold C 10 and the second concentration threshold C 20 . When C > 1500 ppm, it indicates that the refrigerant has a serious leakage. At this time, a large accumulation of the refrigerant will form a significant safety hazard. Therefore, when C > 1500 ppm, the refrigerant leakage mode is determined to be the emergency mode. When 600 ppm < C ≤ 1500 ppm, it indicates that the refrigerant has a slight leakage. At this time, the refrigerant leakage mode can be determined to be the early warning mode, and in this mode, it is necessary to continuously monitor the refrigerant concentration information, etc. When C ≤ 600 ppm, it indicates that the refrigerant content in the current environment is within the safe range, and the heat pump system operates normally.

[0097] Another example is taking the current concentration information and pressure information simultaneously as the conditions for determining the refrigerant leakage mode. The current concentration information is the current change rate of the refrigerant concentration, and the current pressure information includes the current change rate of the exhaust pressure and the current change rate of the suction pressure. The first change rate threshold R c1 is 20 ppm / s, and the pressure change rate threshold R P0 is 5 KPa / s for illustration. When R c > 20 ppm / s, and max(|R P1 |, |R P2 |) > 5 KPa / s, it indicates that the concentration and pressure change too fast, and the refrigerant has a serious leakage. At this time, the refrigerant leakage mode can be determined to be the emergency mode. When R c ≤ 20 ppm / s, max(|R P1 |, |R P2 |) > 5 KPa / s, although the pressure changes too fast, but the concentration change slows down. At this time, the refrigerant leakage mode can be determined to be the early warning mode. When R c ≤ 20 ppm / s, max(|R P1 |, |R P2 |) ≤ 5 KPa / s, it indicates that the concentration growth rate and pressure fluctuation are gentle, and the refrigerant content in the current environment meets the safe operation standard, and it can be determined as a safe working condition without leakage risk. When R c > 20 ppm / s, max(|R P1 |, |R P2 |) ≤ 5 KPa / s, it indicates that the refrigerant concentration rises abnormally while the pressure remains stable, and there is a potential leakage risk, and continuous attention can be paid.

[0098] Another example is given. Taking the current concentration information and pressure information as the conditions for determining the refrigerant leakage mode, the current concentration information is the current refrigerant concentration, the current pressure information is the pressure difference between the current exhaust and suction, and the current first concentration threshold C 10 is 1500 ppm, and the second concentration threshold C 20 is 600 ppm. The pressure difference threshold ΔP0 is 200 KPa for illustration. When C > 1500 ppm, regardless of the magnitude of ΔP, the refrigerant leakage mode is an emergency mode. When 600 ppm < C ≤ 1500 ppm and ΔP ≤ 200 KPa, it indicates that the refrigerant concentration is relatively high, the pressure difference between the high-pressure side and the low-pressure side is unbalanced, and the refrigerant leakage is relatively serious. At this time, a large accumulation of refrigerant will form a significant safety hazard, so the refrigerant leakage mode can be determined as an emergency mode. When 600 ppm < C ≤ 1500 ppm and ΔP > 200 KPa, it indicates that the refrigerant leakage is relatively minor, so the refrigerant leakage mode can be determined as a warning mode. When C ≤ 600 ppm and ΔP > 200 KPa, both the refrigerant concentration and the pressure difference are within the safe range, and the heat pump system operates normally. When C ≤ 600 ppm and ΔP ≤ 200 KPa, it indicates that the pressure difference between the high-pressure side and the low-pressure side of the heat pump system is unbalanced.

[0099] Another example is given. Taking the current concentration information and pressure information as the conditions for determining the refrigerant leakage mode, the current concentration information includes the current refrigerant concentration and the current change rate of the refrigerant concentration, the current pressure information is the current change rate of the exhaust pressure and the current change rate of the suction pressure, the first concentration threshold C 10 is 1500 ppm, the second concentration threshold C 20 is 600 ppm, the first change rate threshold of concentration R c1 is 20 ppm / s, and the pressure change rate threshold R P0 is 5 KPa / s for illustration. When C > 1500 ppm, regardless of the current change rate of the refrigerant concentration R c , the current change rate of the exhaust pressure R P1 , and the current change rate of the suction pressure R P2 's magnitude, the refrigerant leakage mode is an emergency mode. When 600 ppm < C ≤ 1500 ppm, R c > 20 ppm / s, and max(|R P1 |, |R P2 |)> 5 KPa / s, it indicates that serious refrigerant leakage has occurred. At this time, the refrigerant leakage mode can be determined as an emergency mode. When C ≤ 600 ppm, or R c ≤ 20 ppm / s, or max(|R P1 |, |R P2 |)≤ 5 KPa / s, the refrigerant leakage mode does not meet the conditions of the emergency mode.

[0100] For another example, taking the current concentration information and pressure information as the conditions for determining the refrigerant leakage mode, the current concentration information includes the current refrigerant concentration and the current change rate of the refrigerant concentration, and the current pressure information includes the current change rate of the exhaust pressure, the current change rate of the suction pressure, and the pressure difference between the current exhaust and suction. The first concentration threshold C 10 is 1500 ppm, the second concentration threshold C 20 is 600 ppm, the pressure difference threshold ΔP0 is 200 Kpa, the first concentration change rate threshold R c1 is 20 ppm / s, and the pressure change rate threshold R P0 is 5 KPa / s for illustration. When C > 1500 ppm, regardless of the current change rate R c of the current refrigerant concentration, the current change rate R P1 of the current exhaust pressure, the current change rate R P2 of the current suction pressure, and the magnitude of the pressure difference ΔP between the current exhaust and suction, the refrigerant leakage mode is an emergency mode. When R c > 20 ppm / s, max(|R P1 |, |R P2 |) > 5 KPa / s, 600 ppm < C ≤ 1500 ppm and ΔP ≤ 200 KPa, it indicates that the refrigerant has a serious leakage, and at this time, it can be determined that the refrigerant leakage mode is an emergency mode. When R c ≤ 20 ppm / s, or max(|R P1 |, |R P2 |) ≤ 5 KPa / s, or C ≤ 600 ppm, or ΔP > 200 KPa, the refrigerant leakage mode does not meet the conditions of the emergency mode.

[0101] In one embodiment, the step of "selectively controlling the power load in the heat pump system to stop working according to the determined refrigerant leakage mode" specifically includes:

[0102] When it is determined that the refrigerant leakage mode is an emergency mode, control the power load to stop working.

[0103] It should be noted that the power load is determined according to the specific configuration of the heat pump system. When the heat pump system includes a compressor, electric auxiliary heating, and a delivery pump, the power load includes the compressor, electric auxiliary heating, and the delivery pump. When the heat pump system includes a compressor, the power load is the compressor.

[0104] For illustration, taking the case where only a compressor is configured in the heat pump system. When it is determined that the refrigerant leakage mode is an emergency mode, due to the serious leakage of the refrigerant, in order to avoid potential safety hazards that may be caused by the serious leakage of the refrigerant, control the compressor to stop working.

[0105] To illustrate further, let's take a heat pump system with a compressor, electric auxiliary heater, and delivery pump as an example. When the refrigerant leak mode is determined to be emergency mode, the compressor, electric auxiliary heater, and delivery pump are simultaneously shut down to avoid potential safety hazards caused by severe refrigerant leakage.

[0106] Furthermore, the steps of "controlling the power load to stop working" may include, before, after, or simultaneously with, the following:

[0107] Control the ventilation load in the heat pump system to operate at maximum ventilation capacity; and / or

[0108] Issue the first alert.

[0109] It should be noted that the ventilation load is also determined based on the specific configuration of the heat pump system. When the heat pump system includes a fan, the ventilation load is the fan. The fan's location varies depending on the type of heat pump. For integrated heat pumps, the fan is located inside the integrated heat pump casing; for split-type heat pumps, the fan is located in the indoor unit casing. Integrated heat pumps have electrically operated ventilation windows on their casing, which can be opened simultaneously with the fan operation to dilute leaked refrigerant. Split-type heat pumps can alert the user to open the windows for ventilation.

[0110] Furthermore, the primary alarm method in this application is not limited and can include audible alarms, visual alarms, remote notification alarms, etc. Audible alarms include buzzer alarms, siren alarms, and voice prompts. Visual alarms include warning lights and flashing lights. Remote notification alarms include SMS alarms and telephone alarms. The primary alarm method is determined based on the specific configuration of the heat pump system.

[0111] For example, consider a heat pump system with a fan and compressor. When the refrigerant leak mode is determined to be emergency mode, the compressor is stopped. Before, after, or simultaneously with stopping the compressor, the fan can be controlled to run at its maximum speed to ensure maximum ventilation capacity.

[0112] To illustrate further, consider a heat pump system equipped with a fan, compressor, and three electrically operated ventilation windows. When the refrigerant leak mode is determined to be emergency mode, the compressor is stopped. Before, after, or simultaneously with the compressor shutdown, the fan is activated, and the three electrically operated ventilation windows are opened synchronously to rapidly enhance ventilation and accelerate the discharge of leaked refrigerant.

[0113] To illustrate further, let's consider a heat pump system equipped with a fan, compressor, buzzer alarm, warning bell, warning light, and SMS alarm, with the fan operating at multiple speeds. When the refrigerant leak mode is determined to be emergency mode, the compressor is stopped. Before, after, or simultaneously with the compressor shutdown, the fan can be controlled to run at its maximum speed, and an initial alarm can be triggered. This initial alarm includes a buzzer alarm, warning bell, warning light, and SMS alarm. The buzzer and warning bell sound to provide on-site warning, the warning light illuminates to enhance visual alertness, and the SMS alarm automatically sends an emergency notification to preset contacts to ensure rapid response. All alarm methods are activated simultaneously, forming a multi-dimensional early warning mechanism involving sound, light, and remote monitoring to maximize safety.

[0114] In one implementation, the step of "determining, based on the refrigerant leakage pattern, to selectively control the power load in the heat pump system to stop operating" specifically includes:

[0115] When the refrigerant leakage mode is determined to be the warning mode, the ventilation load in the heat pump system is controlled to operate at the minimum ventilation capacity.

[0116] For example, consider a heat pump system with a fan configured accordingly. When the refrigerant leak mode is determined to be the warning mode, a minor refrigerant leak will cause the fan to operate at its minimum speed. This dilutes the leaking refrigerant, preventing accumulation and effectively promoting its diffusion, while also avoiding equipment damage or user inconvenience caused by the compressor stopping.

[0117] To illustrate further, let's take a heat pump system with a fan and three motorized ventilation windows as an example. When the refrigerant leak mode is determined to be the warning mode, the fan is controlled to run at the lowest speed, and only one motorized ventilation window is opened. This effectively controls the impact of the leak while avoiding equipment shock or user inconvenience caused by sudden shutdown.

[0118] Furthermore, the steps of "controlling the ventilation load in the heat pump system to operate at minimum ventilation capacity" may include, before, after, or simultaneously with, the following:

[0119] Reduce the operating frequency of the power load; and / or

[0120] Issue a second alert.

[0121] It should be noted that the second alarm method can be the same as or different from the first alarm method. As long as it effectively triggers human intervention and is handled in a timely manner by humans, the operational safety and reliability of the entire system can be significantly improved.

[0122] For example, consider a heat pump system with a compressor and fan. When a refrigerant leak is detected as a warning mode, the fan is controlled to operate at its minimum speed. Before, after, or simultaneously with the fan operating at its minimum speed, the compressor's operating frequency is reduced. This ensures safe operation while preventing unnecessary shutdowns triggered by minor leaks, reducing the possibility of users circumventing safety protection mechanisms, and thus improving the reliability of the heat pump system.

[0123] To illustrate further, let's consider a heat pump system equipped with a compressor, fan, buzzer alarm, warning bell alarm, warning light, and SMS alarm, with the fan operating at multiple speeds. When the refrigerant leak mode is determined to be the warning mode, the control fan operates at its minimum speed. Before, after, or simultaneously with the control fan operating at its minimum speed, the compressor's operating frequency can be reduced, and a second alarm can be issued. The second alarm includes one of the following: buzzer alarm, warning bell alarm, warning light, or SMS alarm. This allows for manual intervention, improving safety and reliability.

[0124] In one implementation, the step of "controlling the ventilation load in the heat pump system to operate at minimum ventilation capacity" further includes:

[0125] After a set time period, acquire the current concentration and pressure information;

[0126] Based on the current concentration and pressure information, determine whether the heat pump system meets the conditions for resuming normal operation.

[0127] When the conditions for restoring normal operation are met, the control power load is restored to the operating state before entering the warning mode;

[0128] The conditions for resuming normal operation mode include the following:

[0129] The current refrigerant concentration is less than or equal to the refrigerant concentration at the previous moment;

[0130] The absolute value of the current rate of change of exhaust pressure is less than or equal to the absolute value of the rate of change of exhaust pressure at the previous moment.

[0131] The absolute value of the current rate of change of inspiratory pressure is less than or equal to the absolute value of the rate of change of inspiratory pressure at the previous moment.

[0132] For example, consider a heat pump system with a compressor and fan configured, with an initial set time of 60 seconds. After controlling the fan to operate at its minimum speed, the duration of this minimum speed operation is recorded. After 60 seconds, the current refrigerant concentration C` and the current discharge pressure change rate R` are obtained. P1 and the rate of change of current inspiratory pressure R` P2 When C`≤C, |R` P1|≤|R P1 |,|R` P2 |≤|R P2 | indicates that the refrigerant leakage has not worsened. At this point, the heat pump system meets the conditions for resuming normal operation, and the compressor's operating frequency is restored to the state before entering the warning mode. If C`≤C, |R` P1 |≤|R P1 |,|R` P2 |≤|R P2 If any one or two of these conditions are not met, then the subsequent judgment based on the first preset condition is required.

[0133] In one implementation, the control method further includes:

[0134] Based on the current concentration information and / or current pressure information, determine whether the heat pump system meets the first preset condition;

[0135] When the first preset condition is met, the power load is controlled to stop working.

[0136] The first preset condition serves as the criterion for determining whether the refrigerant leak mode is in emergency mode. When the heat pump system meets the first preset condition, the refrigerant leak mode is determined to be in emergency mode, and the power load is stopped. The method for determining whether the refrigerant leak mode is in emergency mode is the same as above and will not be repeated here.

[0137] In one implementation, the step of "acquiring current concentration information every second predetermined time interval" is followed by:

[0138] The ventilation load in the heat pump system operates for a third set time;

[0139] Within the third set time period, the current concentration information is acquired every second set time period.

[0140] The third set time is longer than the second set time.

[0141] It should be noted that controlling the ventilation load to operate at maximum ventilation capacity for at least the third set time helps accelerate airflow, dilute and expel leaked refrigerant, prevent refrigerant accumulation in localized areas, and thus ensure that the ventilation load can still handle residual refrigerant after the power load stops operating, avoiding secondary refrigerant accumulation. This application does not impose a limit on the third set time, as long as it can accelerate airflow and dilute and expel leaked refrigerant. For example, the third set time can be greater than or equal to 300 seconds.

[0142] For example, consider a heat pump system with a compressor and fan configured, a second set time of 10 seconds, a third set time of 300 seconds, and M = 30 units. When the refrigerant leak mode is in emergency mode, the compressor stops working and the fan runs at maximum speed for 300 seconds. Within these 300 seconds, the current refrigerant concentration C`` and the current refrigerant concentration change rate R` are acquired at sampling points every 10 seconds. C The current refrigerant concentration C`` and the current refrigerant concentration change rate R`` were obtained from 30 sampling points. C .

[0143] In one implementation, the step of "controlling the power load to stop working" further includes:

[0144] Every second set time interval, the current concentration information is obtained, and the current refrigerant concentration and the rate of change of current refrigerant concentration at M sampling points are obtained;

[0145] Based on the current refrigerant concentration and the rate of change of the current refrigerant concentration at M sampling points, determine whether N consecutive sampling points among the M sampling points simultaneously meet the third preset condition.

[0146] When the N consecutive sampling points simultaneously meet the third preset condition, the heat pump system meets the condition for relieving the refrigerant leakage mode.

[0147] Control the power load to restart operation;

[0148] The third preset condition includes the following conditions:

[0149] The current refrigerant concentration is less than or equal to the third concentration threshold;

[0150] The absolute value of the current refrigerant concentration change rate is less than or equal to the second concentration change rate threshold;

[0151] Wherein, the third concentration threshold is less than the second concentration threshold, the second concentration change rate threshold is less than the first concentration change rate threshold, and M>N≥2.

[0152] It should be noted that the third preset condition includes two conditions: a concentration threshold condition and a concentration change rate condition. The concentration threshold condition requires the current refrigerant concentration to be less than or equal to the third concentration threshold. The concentration change rate condition requires the absolute value of the current refrigerant concentration change rate to be less than or equal to the second concentration change rate threshold. Only when N consecutive sampling points simultaneously meet the third preset condition can the leak be confirmed as resolved, effectively avoiding misjudgments caused by instantaneous data fluctuations. If the N sampling points are not consecutive, or if one or more of the N consecutive sampling points do not meet the third preset condition, the refrigerant leak is considered to continue to avoid misjudgments caused by instantaneous data fluctuations. It should also be noted that if N consecutive sampling points out of M points simultaneously meet the third preset condition, even if the ventilation load's operating time has not yet reached the third set time, the ventilation load must continue to operate until the ventilation load has run for the full third set time. This effectively prevents refrigerant accumulation in localized areas, accelerates air circulation, and further improves system safety.

[0153] Here, "N consecutive sampling points" refers to N adjacent sampling points collected at fixed intervals. For example, if the current refrigerant concentration and the rate of change of the current refrigerant concentration are collected every second, then "N consecutive sampling points" are the N measurements obtained sequentially within N seconds. When the system detects that the values ​​of N consecutive sampling points simultaneously meet the third preset condition, that is, the heat pump system meets the conditions for de-leaking mode.

[0154] For example, in a heat pump system configured with a compressor and a fan, the second set time is 10 seconds, the third set time is 300 seconds, M is 30, N is 10, the third concentration threshold is 500 ppm, and the second concentration change rate threshold R... c2 The value is 1 ppm / s. When the refrigerant leak mode is in emergency mode, the compressor stops working and the fan runs at maximum speed for 300 seconds. Within these 300 seconds, the current refrigerant concentration C`` and the current refrigerant concentration change rate R` are acquired at the sampling point every 10 seconds. C The current refrigerant concentration C`` and the current refrigerant concentration change rate R`` were obtained from 30 sampling points. C If 10 consecutive sampling points out of these 30 points simultaneously meet the third preset condition, the third preset condition is C``≤500ppm and |R`` C If |≤1ppm / s, the heat pump system is considered to meet the conditions for relieving the refrigerant leakage mode, and the compressor is controlled to restart.

[0155] In one implementation, the process further includes the following before "controlling the power load to restart operation":

[0156] Control the heat pump system to enter a reset mode;

[0157] Determine whether the heat pump system meets the reset conditions;

[0158] When the reset condition is met, the power load is restarted.

[0159] The reset conditions include at least one of the following conditions:

[0160] The heat pump system has been in the reset mode for longer than the fourth preset time.

[0161] A reset command has been received.

[0162] It should be noted that after the heat pump system meets the conditions for deactivating the refrigerant leak mode, the system enters a standby reset mode. This ensures the safety and controllability of the power load restart process and effectively avoids unnecessary user operations such as disassembly or jumper resets due to false alarms. In standby reset mode, the heat pump system must meet reset conditions for the power load to restart. These reset conditions include at least one of the following two conditions: one is that the heat pump system has been in standby reset mode for more than a fourth set time; the other is that a reset command has been received. As long as at least one of these conditions is met, the heat pump system meets the reset conditions. The first condition is automatic reset, which automatically triggers the power load restart operation after the heat pump system has been running in standby reset mode for more than the fourth set time. The second condition includes manual reset and maintenance reset. Manual reset includes user confirmation via buttons, touchscreen, remote platform, or QR code, thereby triggering the power load restart operation. Maintenance reset includes reset by maintenance personnel via maintenance interface or password, thereby triggering the power load restart operation.

[0163] The following is combined with Figure 2 This paper briefly describes one possible operating process of the refrigerant leakage control method for the heat pump system of this application. Figure 2 This is a logic diagram of a possible implementation of the refrigerant leakage control method for the heat pump system of this application.

[0164] S201, Obtain current concentration and pressure information. Current concentration information includes current refrigerant concentration C and current refrigerant concentration change rate R. C Current pressure information includes the current pressure difference between exhaust and intake air, ΔP, and the current rate of change of exhaust pressure, R. P1 and the rate of change of current inspiratory pressure R P2 Then execute S202.

[0165] S202, determine if C > 1500ppm? If yes, proceed to S205; otherwise, proceed to S203.

[0166] S203, determine if Rc>20ppm / s and max(|R P1 |,|R P2|)>5KPa / s? If yes, execute S205; otherwise execute S204.

[0167] S204, determine whether 600ppm < C ≤ 1500ppm and ΔP > 200KPa? If yes, execute S205; otherwise execute S215.

[0168] S205, determine the refrigerant leakage mode as the emergency mode, and then execute S206.

[0169] S206, control the compressor to stop running and the fan to run at the maximum speed gear, and then execute S207.

[0170] S207, the fan runs at the maximum speed gear for 300s, and then execute S208.

[0171] S208, obtain C`` and R`` every 10s within 300s C to obtain C`` and R`` of 30 sampling points C and then execute S209.

[0172] S209, determine whether 10 consecutive sampling points among 30 sampling points simultaneously satisfy C`` ≤ 500ppm and |R``c| ≤ 1ppm / s? If yes, execute S210; otherwise execute S207.

[0173] S210, meet the conditions for解除泄漏模式 (it seems there is a wrong expression here, assuming it should be "解除泄漏模式" as "meeting the conditions to解除 the leakage mode"), control the heat pump system to enter the待复位模式 (assuming it should be "待复位模式" as "waiting for reset mode"), and then execute S211.

[0174] S211, obtain the time when entering the waiting for reset mode, and then execute S212.

[0175] S212, determine whether the time of entering the waiting for reset is greater than 30s? If yes, execute S214; otherwise execute S213.

[0176] S213, determine whether a reset instruction is received? If yes, execute S214; otherwise execute S211, and then execute S214.

[0177] S214, control the compressor to restart running and the fan to stop running, and then execute S201.

[0178] S215, determine whether 600ppm < C ≤ 1500ppm? If yes, execute S217; otherwise execute S216.

[0179] S216, determine whether max(|R P1 |, |R P2 |)>5KPa / s? If yes, execute S217; otherwise execute S201.

[0180] It should be noted that there are some unclear or potentially incorrect expressions in the original text, such as "解除泄漏模式" which might need to be corrected to a proper term. Also, "待复位模式" might need to be further defined or corrected for a more accurate translation.S217, determine that the refrigerant leakage mode is the warning mode, and then execute S218.

[0181] S218, reduce the operating frequency of the compressor and operate the fan at the minimum speed gear, and then execute S219.

[0182] S219, obtain the current concentration information and the current pressure information. The current concentration information includes the current refrigerant concentration C` and the current change rate of the refrigerant concentration R`. C , the current pressure information includes the pressure difference ΔP` between the current exhaust and suction, the current change rate of the exhaust pressure R`, P1 and the current change rate of the suction pressure R`. P2 , and then execute S220.

[0183] S220, determine whether C` ≤ C, |R` P1 | ≤ |R P1 | and |R` P1 | ≤ |R P2 |? If so, execute S221; otherwise, execute S222.

[0184] S221, the heat pump system meets the conditions for resuming the normal operation mode, control the compressor to resume the operation state before entering the warning mode, and then execute S201.

[0185] S222, determine whether C` > 1500 ppm? If so, execute S205; otherwise, execute S223.

[0186] S223, determine whether R`c > 20 ppm / s and max(|R` P1 |, |R` P2 |) > 5 KPa / s? If so, execute S205; otherwise, execute S224.

[0187] S224, determine whether 600 ppm < C` ≤ 1500 ppm and ΔP` > 200 KPa? If so, execute S205; otherwise, execute S219.

[0188] Those skilled in the art can understand that although some embodiments herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the claims of the present application, any one of the claimed embodiments can be used in any combination.

[0189] The technical solutions of this application have been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for controlling refrigerant leakage in a heat pump system, characterized in that, The refrigerant leakage control method includes: Obtain current concentration information and / or current pressure information; the current concentration information includes at least one of the current refrigerant concentration and the current refrigerant concentration change rate, and the current pressure information includes at least one of the current exhaust and intake pressure difference, the current exhaust pressure change rate, and the current intake pressure change rate. Based on the current concentration information and / or the current pressure information, a refrigerant leakage mode is determined; the refrigerant leakage mode includes a warning mode and an emergency mode; Based on the determined refrigerant leakage pattern, the power load in the heat pump system is selectively controlled to stop operating.

2. The refrigerant leakage control method according to claim 1, characterized in that, The step of "determining the refrigerant leakage mode based on the concentration information and / or the pressure information" specifically includes: When the first preset condition is met, the refrigerant leakage mode is determined to be the emergency mode; When the second preset condition is met, the refrigerant leakage mode is determined to be the warning mode: The first preset condition includes at least one of the following conditions: The current refrigerant concentration is greater than the first concentration threshold; The current refrigerant concentration change rate is greater than the first concentration change rate threshold, and the larger of the absolute values ​​of the current exhaust pressure change rate and the current intake pressure change rate is greater than the pressure change rate threshold. The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold, and the pressure difference is less than or equal to the pressure difference threshold; The second preset condition includes at least one of the following conditions: The current refrigerant concentration is greater than the second concentration threshold and less than or equal to the first concentration threshold; The larger of the absolute values ​​of the current exhaust pressure change rate and the current intake pressure change rate is greater than the pressure change rate threshold.

3. The refrigerant leakage control method according to claim 2, characterized in that, The step of "selectively controlling the power load in the heat pump system to stop working based on the determined refrigerant leakage mode" specifically includes: When the refrigerant leakage mode is determined to be the emergency mode, the power load is controlled to stop working.

4. The refrigerant leakage control method according to claim 3, characterized in that, The steps include, before, after, or simultaneously with, the step of "controlling the power load to stop working". Control the ventilation load in the heat pump system to operate at maximum ventilation capacity; and / or Issue the first alert.

5. The refrigerant leakage control method according to claim 2, characterized in that, The step of "selectively controlling the power load in the heat pump system to stop working based on the refrigerant leakage mode" specifically includes: When the refrigerant leakage mode is determined to be the warning mode, the ventilation load in the heat pump system is controlled to operate at the minimum ventilation capacity.

6. The refrigerant leakage control method according to claim 5, characterized in that, The step of "controlling the ventilation load in the heat pump system to operate at minimum ventilation capacity" includes, before, after, or simultaneously with, the following: Reduce the operating frequency of the power load; and / or Issue a second alert.

7. The refrigerant leakage control method according to claim 5, characterized in that, The step of "controlling the ventilation load in the heat pump system to operate at minimum ventilation capacity" also includes: After a set time period, acquire the current concentration and pressure information; Based on the current concentration and pressure information, determine whether the heat pump system meets the conditions for resuming normal operation. When the conditions for restoring the normal operating mode are met, the power load is controlled to return to the operating state before entering the warning mode; The conditions for restoring the normal operating mode include the following: The current refrigerant concentration is less than or equal to the refrigerant concentration at the previous moment; The absolute value of the current rate of change of exhaust pressure is less than or equal to the absolute value of the rate of change of exhaust pressure at the previous moment. The absolute value of the current rate of change of inspiratory pressure is less than or equal to the absolute value of the rate of change of inspiratory pressure at the previous moment.

8. The refrigerant leakage control method according to claim 7, characterized in that, The refrigerant leakage control method also includes: Based on the current concentration information and / or current pressure information, determine whether the heat pump system meets the first preset condition; When the first preset condition is met, the power load is controlled to stop working.

9. The refrigerant leakage control method according to claim 3, 4 or 8, characterized in that, The step of "controlling the power load to stop working" also includes: Every second set time interval, the current concentration information is obtained, and the current refrigerant concentration and the rate of change of current refrigerant concentration at M sampling points are obtained; Based on the current refrigerant concentration and the rate of change of the current refrigerant concentration at M sampling points, determine whether N consecutive sampling points among the M sampling points simultaneously meet the third preset condition. When the N consecutive sampling points simultaneously meet the third preset condition, the heat pump system meets the condition for relieving the refrigerant leakage mode. Control the power load to restart operation; The third preset condition includes the following conditions: The current refrigerant concentration is less than or equal to the third concentration threshold; The absolute value of the current refrigerant concentration change rate is less than or equal to the second concentration change rate threshold; Wherein, the third concentration threshold is less than the second concentration threshold, the second concentration change rate threshold is less than the first concentration change rate threshold, and M>N≥2.

10. The refrigerant leakage control method according to claim 9, characterized in that, The step of "obtaining current concentration information every second set time interval" is preceded by: Control the ventilation load in the heat pump system to operate for a third set time; During the third set time period, the current concentration information is acquired every second set time period. Wherein, the third set time is greater than the second set time; and / or The following is included before "controlling the power load to restart operation": The heat pump system is controlled to enter a reset mode; Determine whether the heat pump system meets the reset conditions; When the reset condition is met, the power load is controlled to restart operation; The reset condition includes at least one of the following conditions: The heat pump system remains in the reset mode for more than a fourth preset time. A reset command has been received.

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