A freeze protection control method and apparatus for a low temperature heat pump

Abstract

The application provides a freeze-proof control method and device for a low-temperature heat pump. On the basis of a freeze-proof control first-level freeze-proof logic and a freeze-proof control second-level freeze-proof logic, a freeze-proof judgment correlation condition of a freeze-proof starting basic ambient temperature and an inlet and outlet water temperature difference is set. According to the freeze-proof judgment correlation condition, freeze-proof water pump starting control is carried out, a water flow switch state is monitored and determined, freeze-proof water pump starting logic control and compressor start-stop control are carried out. The inlet and outlet water temperature difference of the unit and the high-pressure protection state are monitored and determined, freeze-proof water pump and compressor linkage control and water flow monitoring freeze-proof logic state determination are carried out. According to the water flow monitoring freeze-proof logic state determination, a circulating freeze-proof logic state is intelligently controlled, and freeze-proof intelligent control of the low-temperature heat pump is carried out.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy and energy-saving intelligent control, more specifically, the present application relates to a freeze protection control method and system for low-temperature heat pumps. BACKGROUND

[0002] Low-temperature heat pumps are energy-efficient devices that use a small amount of electrical energy to transfer heat from the environment to a higher temperature. However, the freeze protection for the water flow switch is often ineffective. If the water flow switch is turned off, the water pump may be damaged if the freeze protection is turned on, and the unit may be frozen if the freeze protection is turned off. Therefore, it is crucial to improve the protection effect in abnormal situations. Low-temperature heat pumps absorb heat from the air in the evaporator through refrigerant, and then release heat in the condenser to achieve heating. In low-temperature environments, heat pump units are prone to freezing, which can damage the equipment and affect its normal operation. Therefore, it is essential to further improve the application of freeze protection control systems in low-temperature heat pumps. The existing freeze protection control system lacks sufficient flexibility and intelligence when dealing with the situation where the water flow switch is turned off, and cannot be adjusted according to the actual situation, which may result in poor freeze protection and even more serious problems. Therefore, it is necessary to propose a freeze protection control method and system for low-temperature heat pumps to at least partially solve the problems in the prior art. SUMMARY

[0003] In the summary section, a series of simplified concepts are introduced, which will be further described in the detailed description section. The summary section of the present application does not mean to attempt to limit the key features and necessary technical features of the claimed technical solution, nor does it attempt to determine the protection scope of the claimed technical solution.

[0004] To at least partially solve the above problems, the present application provides a freeze protection control method for low-temperature heat pumps, comprising:

[0005] S100, on the basis of the freeze protection control primary freeze protection logic and the freeze protection control secondary freeze protection logic, set the freeze protection start basic environment temperature and the freeze protection judgment correlation condition of the inlet and outlet water temperature difference;

[0006] S200, according to the freeze protection judgment correlation condition, perform freeze protection water pump start control, monitor and determine the water flow switch state, perform freeze protection water pump start logic control and compressor start-stop control;

[0007] S300, monitor and determine the inlet and outlet water temperature difference of the unit and the high-pressure protection state, perform freeze protection water pump and compressor linkage control, and water flow monitoring freeze protection logic state determination;

[0008] S400, according to the water flow monitoring anti-freezing logic state judgment, intelligently control the circulation anti-freezing logic state, and perform the anti-freezing intelligent control of the low-temperature heat pump.

[0009] Preferably, S100 comprises:

[0010] S101, input the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump;

[0011] S102, based on the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic, set the anti-freezing starting basic ambient temperature reaching the anti-freezing condition, and set the water inlet and outlet temperature difference for judging the anti-freezing logic state;

[0012] S103, according to the anti-freezing starting basic ambient temperature and the water inlet and outlet temperature difference, establish the anti-freezing judgment correlation condition.

[0013] Preferably, S200 comprises:

[0014] S201, according to the anti-freezing judgment correlation condition, judge the anti-freezing starting basic ambient temperature;

[0015] S202, according to the anti-freezing starting basic ambient temperature, when the anti-freezing starting basic ambient temperature condition is reached, trigger the anti-freezing starting signal;

[0016] S203, according to the anti-freezing starting signal, when the anti-freezing starting signal appears, monitor the anti-freezing water pump starting multiple times, monitor the water flow switch state, control the anti-freezing logic state and the compressor start-stop operation, and obtain the water flow monitoring anti-freezing logic state;

[0017] The anti-freezing water pump starting multiple times comprises: the anti-freezing water pump starting three times or the anti-freezing water pump starting three times or less;

[0018] Monitoring the anti-freezing water pump starting multiple times and monitoring the water flow switch state, controlling the anti-freezing logic state and the compressor start-stop operation comprises: monitoring the anti-freezing water pump starting multiple times, when the anti-freezing water pump starts three times or the anti-freezing water pump starts three times or less, monitoring the water flow switch state, controlling the anti-freezing logic state and the compressor start-stop operation; according to the water flow switch state, if the water flow switch is restored, entering the normal anti-freezing logic state, starting the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic; if the water flow switch is not restored, starting the compressor after starting the anti-freezing water pump again.

[0019] Preferably, S300 comprises:

[0020] S301, according to the anti-freezing water pump and compressor linkage control and the water flow monitoring anti-freezing logic state, further monitor and judge the water inlet and outlet temperature of the unit, and calculate the water inlet and outlet temperature difference;

[0021] S302, judging whether the temperature difference between the inlet water and the outlet water is in a normal range and high pressure protection linkage determination, and performing anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination.

[0022] Preferably, S400 comprises:

[0023] S401, according to the anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination, if the temperature difference between the inlet water and the outlet water is in the normal range and high pressure protection does not occur, the anti-freezing water pump and the compressor continue to run until the anti-freezing condition is reached and the anti-freezing state is exited; if the temperature difference between the inlet water and the outlet water exceeds the normal range or high pressure protection occurs, the anti-freezing water pump is stopped, and the compressor is stopped, and the device as a whole enters a water flow abnormal anti-freezing logic step;

[0024] S402, when entering the water flow abnormal anti-freezing logic step, the water pump is not started first, and the compressor is directly triggered to start until the compressor fails to stop; when the compressor fails to stop, if the anti-freezing condition has not been reached, the compressor is started again after 30 minutes, and the compressor is run for anti-freezing until the compressor fails to stop;

[0025] S403, the intelligent control cycle anti-freezing logic state is continuously cycled in the water flow abnormal anti-freezing logic state logic step until the anti-freezing condition is reached and the anti-freezing state is exited; and the anti-freezing intelligent control of the low-temperature heat pump is performed.

[0026] The application provides an anti-freezing control device of a low-temperature heat pump, comprising:

[0027] The anti-freezing judgment correlation setting module sets anti-freezing judgment correlation conditions of the anti-freezing starting basic ambient temperature and the temperature difference between the inlet water and the outlet water on the basis of the anti-freezing control primary anti-freezing logic and the anti-freezing control secondary anti-freezing logic of the low-temperature heat pump;

[0028] The water pump water flow switch control module performs anti-freezing water pump starting control according to the anti-freezing judgment correlation conditions, monitors and determines the water flow switch state, and performs anti-freezing water pump starting logic control and compressor start-stop control;

[0029] The water temperature high pressure protection linkage determination module monitors and judges the temperature difference between the inlet water and the outlet water and the high pressure protection state of the unit, and performs anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination;

[0030] The cycle anti-freezing intelligent control module intelligently controls the cycle anti-freezing logic state according to the water flow monitoring anti-freezing logic state determination, and performs anti-freezing intelligent control of the low-temperature heat pump.

[0031] Preferably, the anti-freezing judgment correlation setting module comprises:

[0032] The heat pump anti-freezing logic input sub-module inputs the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump.

[0033] The anti-freezing starting temperature difference setting sub-module sets the anti-freezing starting basic ambient temperature reaching the anti-freezing condition and sets the water inlet and outlet temperature difference for judging the anti-freezing logic state based on the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic.

[0034] The anti-freezing correlation condition creating sub-module creates the anti-freezing judgment correlation condition according to the anti-freezing starting basic ambient temperature and the water inlet and outlet temperature difference.

[0035] Preferably, the water pump water flow switch control module comprises:

[0036] The ambient temperature anti-freezing judgment sub-module judges the anti-freezing starting basic ambient temperature according to the anti-freezing judgment correlation condition.

[0037] The anti-freezing starting signal triggering sub-module triggers the anti-freezing starting signal when the anti-freezing starting basic ambient temperature condition is reached according to the anti-freezing starting basic ambient temperature.

[0038] The water pump switch monitoring control sub-module controls the anti-freezing logic state and the compressor start-stop operation to obtain the water flow monitoring anti-freezing logic state according to the anti-freezing starting signal when the anti-freezing starting signal appears, monitors the anti-freezing water pump starting multiple times, and monitors the water flow switch state.

[0039] The anti-freezing water pump starting multiple times comprises three times of anti-freezing water pump starting or less than three times of anti-freezing water pump starting.

[0040] Monitoring the anti-freezing water pump starting multiple times and monitoring the water flow switch state to control the anti-freezing logic state and the compressor start-stop operation comprises monitoring the anti-freezing water pump starting multiple times, monitoring the water flow switch state, controlling the anti-freezing logic state and the compressor start-stop operation when the anti-freezing water pump starts three times or less than three times, and starting the compressor after the anti-freezing water pump is started again if the water flow switch is not restored.

[0041] Preferably, the water temperature high-pressure protection linkage judgment module comprises:

[0042] The unit water temperature difference calculation sub-module further monitors and judges the water inlet and outlet temperature of the unit according to the anti-freezing water pump and compressor linkage control and the water flow monitoring anti-freezing logic state, and calculates the water inlet and outlet temperature difference.

[0043] The linkage control anti-freezing logic determination sub-module determines whether the temperature difference between the inlet and outlet water is within a normal range and whether high pressure protection linkage determination is met, and performs linkage control of the anti-freezing water pump and the compressor and water flow monitoring anti-freezing logic state determination.

[0044] Preferably, the circulating anti-freezing intelligent control module comprises:

[0045] The linkage operation abnormality analysis sub-module determines the anti-freezing water pump and the compressor linkage control and water flow monitoring anti-freezing logic state determination, and if the temperature difference between the inlet and outlet water is within a normal range and high pressure protection is not met, the anti-freezing water pump and the compressor continue to operate until the anti-freezing condition is met and the anti-freezing state is exited; if the temperature difference between the inlet and outlet water is beyond the normal range or high pressure protection is met, the anti-freezing water pump is stopped and the compressor is also stopped, and the whole device enters a water flow abnormality anti-freezing logic step.

[0046] The water flow abnormality anti-freezing operation sub-module, when entering the water flow abnormality anti-freezing logic step, does not start the water pump first, directly triggers the start of the compressor, and stops the compressor until the compressor fails; when the compressor fails, if the anti-freezing condition is not met, the compressor is started again after 30 minutes, the anti-freezing operation of the compressor is performed, and the compressor is stopped until the compressor fails.

[0047] The intelligent control circulating anti-freezing sub-module intelligently controls the circulating anti-freezing logic state, continuously circulates the water flow abnormality anti-freezing logic state logic step, until the anti-freezing condition is met and the anti-freezing state is exited, and performs low-temperature heat pump anti-freezing intelligent control.

[0048] Compared with the prior art, the low-temperature heat pump anti-freezing control method and device has at least the following beneficial effects: on the basis of the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump, the anti-freezing start basic environment temperature and the anti-freezing judgment associated condition of the water inlet and outlet temperature difference are set; according to the anti-freezing judgment associated condition, the anti-freezing water pump start control is performed, the water flow switch state is monitored and determined, the anti-freezing water pump start logic control and the compressor start-stop control are performed; the water inlet and outlet temperature difference and the high-pressure protection state of the unit are monitored and determined, the anti-freezing water pump and compressor linkage control and the water flow monitoring anti-freezing logic state determination are performed; according to the water flow monitoring anti-freezing logic state determination, the circulating anti-freezing logic state is intelligently controlled, and the anti-freezing intelligent control of the low-temperature heat pump is performed; the anti-freezing control method can well avoid the anti-freezing failure caused by the disconnection of the water flow switch, can avoid the damage of the water pump caused by idling, and can avoid the damage of the unit caused by the anti-freezing failure; the anti-freezing control method does not increase the cost of anti-freezing control, and has high cost performance; the application of the anti-freezing control method can greatly reduce the failure rate of the heat pump unit in the use process; the anti-freezing control method and device not only focuses on the running state of the heat pump unit based on the environment temperature and the water outlet temperature, but also makes the anti-freezing control more accurate and effective, can better prevent the icing of the heat pump system, and protects the normal operation of the heat pump unit; in the case that the water flow switch is disconnected, the anti-freezing strategy can be adjusted in time, the damage caused by the idling of the water pump is avoided, and the damage caused by the icing of the unit is also prevented, and the overall protection of the heat pump system is realized; the anti-freezing control method and device solve the problems of poor anti-freezing control effect and the inability to effectively prevent freezing after the water flow switch is disconnected in the prior art, improve the operation stability and reliability of the heat pump system, and prolong the service life of the heat pump.

[0049] The low-temperature heat pump anti-freezing control method and device has other advantages, objects and features of the present application, which will be embodied in part through the following description, and will be understood by those skilled in the art through research and practice of the present application. BRIEF DESCRIPTION OF DRAWINGS

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

[0051] Fig. 1 An embodiment diagram of the low-temperature heat pump anti-freezing control method and device is provided.

[0052] Fig. 2 An embodiment diagram of the low-temperature heat pump anti-freezing control method and device water flow control is provided.

[0053] Fig. 3Figure 1 is a multi-point temperature embodiment diagram of a low-temperature heat pump anti-freezing control method and device according to the present application. DETAILED DESCRIPTION

[0054] The present application will be further described in detail below with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement the present application according to the description; as shown in the drawings, the present application provides a low-temperature anti-freezing control method, comprising: Figs. 1-3

[0055] S100, on the basis of the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump, setting an anti-freezing starting basic environment temperature and an anti-freezing judgment associated condition of an inlet and outlet water temperature difference;

[0056] S200, according to the anti-freezing judgment associated condition, performing anti-freezing water pump starting control, monitoring and determining a water flow switch state, performing anti-freezing water pump starting logic control and compressor start-stop control;

[0057] S300, monitoring and determining an inlet and outlet water temperature difference of the unit and a high-pressure protection state, performing anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination;

[0058] S400, according to the water flow monitoring anti-freezing logic state determination, intelligently controlling a circulating anti-freezing logic state, and performing anti-freezing intelligent control of the low-temperature heat pump.

[0059] ​The principle and effect of the above technical solution are: the application provides a freeze-proof control method of a low-temperature heat pump, which comprises the following steps: on the basis of freeze-proof control first-level freeze-proof logic and freeze-proof control second-level freeze-proof logic of the low-temperature heat pump, setting freeze-proof starting basic environment temperature and freeze-proof judgment correlation conditions of water inlet and outlet temperature difference; according to the freeze-proof judgment correlation conditions, performing freeze-proof water pump starting control, monitoring and determining water flow switch state, performing freeze-proof water pump starting logic control and compressor start-stop control; monitoring and determining water inlet and outlet temperature difference and high-pressure protection state of the unit, performing freeze-proof water pump and compressor linkage control and water flow monitoring freeze-proof logic state determination; according to the water flow monitoring freeze-proof logic state determination, intelligently controlling circulating freeze-proof logic state, and performing freeze-proof intelligent control of the low-temperature heat pump; the freeze-proof control method can well avoid freeze-proof failure caused by water flow switch opening, can avoid water pump damage caused by idling, and can avoid unit damage caused by freeze-proof failure; the freeze-proof control method does not increase the cost of freeze-proof control, and has high cost performance; the application of the freeze-proof control method can greatly reduce the failure rate of the heat pump unit in the use process; the freeze-proof control method and device can not only be based on environment temperature and water outlet temperature, but also focus on the running state of the heat pump unit, so that the freeze-proof control is more accurate and effective, the freezing of the heat pump system can be better prevented, and the normal operation of the heat pump unit is protected; in the case that the water flow switch is opened, the freeze-proof strategy can be adjusted in time, the damage caused by water pump idling is avoided, and the damage caused by unit freezing is also prevented, so that the heat pump system is comprehensively protected; the freeze-proof control method and device solve the problems of poor freeze-proof control effect and ineffective freeze-proof after the water flow switch is opened in the prior art, improve the operation stability and reliability of the heat pump system, and prolong the service life of the heat pump;

[0060] The water flow at the water inlet end passes through the anti-freezing water pump, the water flow switch at the water inlet end is controlled to control the on-off and flow rate of the water flow at the water inlet end, the water inlet temperature is detected by the water inlet temperature detector, the water flow at the water inlet end passes through the water-side heat exchanger to perform the first heat exchange, the water flow after the first heat exchange is introduced into the anti-freezing liquid accumulator, the water flow in the anti-freezing liquid accumulator enters the economizer, a part of the water flow in the economizer is throttled and evaporated to enter the compressor to perform the compressor compression process adjustment, another part of the water flow in the economizer is introduced into the subsequent pipeline and the evaporator end through the first electronic expansion valve and the second electronic expansion valve, the water flow at the evaporator end is introduced into the gas distribution through the four-way valve, the water flow after the gas distribution is introduced into the compressor liquid accumulator through the low-pressure switch, the water flow after the compression of the compressor is collected to the four-way valve through the high-pressure switch, the water flow at the outlet end of the four-way valve is returned to the water-side heat exchanger to perform the second heat exchange, the outlet water temperature is detected by the outlet water temperature detector after the second heat exchange, the water flow switch at the water outlet end is controlled to control the on-off and flow rate of the water flow at the water outlet end, the ambient temperature includes the ambient temperature of the water-side heat exchanger, the ambient temperature of the evaporator and the ambient temperature of the accumulator, the ambient temperature of the water-side heat exchanger, the ambient temperature of the evaporator and the ambient temperature of the accumulator are detected by the ambient temperature detector, the ambient temperature of the water-side heat exchanger, the ambient temperature of the evaporator and the ambient temperature of the accumulator are detected by the ambient temperature detector.

[0061] The anti-freezing liquid accumulator comprises an inner wall of the accumulator, a wall layer inter-electric heating wire net, an outer wall of the accumulator and an accumulator ambient temperature detector, the inner wall of the accumulator is used to store the water after the first heat exchange, the wall layer inter-electric heating wire net is arranged between the inner wall of the accumulator and the outer wall of the accumulator, the accumulator ambient temperature detector is used to detect the ambient temperature of the accumulator, when the ambient temperature of the accumulator is lower than the set minimum ambient temperature of the accumulator for anti-freezing, the wall layer inter-electric heating wire net is started to heat to prevent the water after the first heat exchange in the accumulator from freezing.

[0062] In one embodiment, S100 comprises:

[0063] S101, inputting the anti-freezing control primary anti-freezing logic and the anti-freezing control secondary anti-freezing logic of the low-temperature heat pump;

[0064] S102, based on the anti-freezing control primary anti-freezing logic and the anti-freezing control secondary anti-freezing logic, setting the anti-freezing starting basic ambient temperature for reaching the anti-freezing condition and setting the inlet and outlet water temperature difference for determining the anti-freezing logic state;

[0065] S103, establishing the anti-freezing judgment associated condition according to the anti-freezing starting basic ambient temperature and the inlet and outlet water temperature difference.

[0066] The principle and effect of the above technical solution are: the freeze-proof control first-level freeze-proof logic and the freeze-proof control second-level freeze-proof logic of the input low-temperature heat pump; based on the freeze-proof control first-level freeze-proof logic and the freeze-proof control second-level freeze-proof logic, a freeze-proof start basic environment temperature reaching a freeze-proof condition is set, and an inlet and outlet water temperature difference for determining a freeze-proof logic state is set; a freeze-proof judgment correlation condition is established according to the freeze-proof start basic environment temperature and the inlet and outlet water temperature difference; the whole system is initialized, including setting various parameters of the system, such as an environment temperature threshold, an outlet water temperature threshold, a compressor frequency threshold, and an expansion valve opening threshold; the specific setting of these thresholds needs to be adjusted according to the specific model of the heat pump unit and the working environment and other factors; the freeze-proof control first-level freeze-proof logic and the freeze-proof control second-level freeze-proof logic respectively count historical freeze-proof control freeze-proof logic rules to obtain historical freeze-proof control freeze-proof logic statistical big data; according to the freeze-proof control judgment condition level in the historical freeze-proof control freeze-proof logic statistical big data, the freeze-proof control judgment condition level is collected, the first-level freeze-proof logic and the second-level freeze-proof logic are divided, the freeze-proof control first-level freeze-proof logic and the freeze-proof control second-level freeze-proof logic are obtained, and the first-level freeze-proof control and the second-level freeze-proof control are respectively performed according to the first-level freeze-proof logic and the second-level freeze-proof logic.

[0067] In one embodiment, S200 includes:

[0068] S201, determining the freeze-proof start basic environment temperature according to the freeze-proof judgment correlation condition;

[0069] S202, triggering a freeze-proof start signal when the freeze-proof start basic environment temperature condition is reached according to the freeze-proof start basic environment temperature;

[0070] S203, monitoring freeze-proof water pump start multiple times and monitoring water flow switch states to control freeze-proof logic states and compressor start-stop operation according to the freeze-proof start signal when the freeze-proof start signal appears, and obtaining water flow monitoring freeze-proof logic states;

[0071] The freeze-proof water pump start multiple times include: freeze-proof water pump start three times or freeze-proof water pump start three times or less;

[0072] Monitoring freeze-proof water pump start multiple times and monitoring water flow switch states to control freeze-proof logic states and compressor start-stop operation include: monitoring freeze-proof water pump start multiple times, monitoring water flow switch states, controlling freeze-proof logic states and compressor start-stop operation when the freeze-proof water pump starts three times or the freeze-proof water pump starts three times or less; according to the water flow switch states, if the water flow switch is restored, the normal freeze-proof logic state is entered, and the freeze-proof control first-level freeze-proof logic and the freeze-proof control second-level freeze-proof logic are started; if the water flow switch is not restored, the compressor is started after the freeze-proof water pump is started again.

[0073] The principle and effect of the above technical solution are: determining the antifreeze starting basic ambient temperature according to the antifreeze judgment correlation condition; triggering the antifreeze starting signal when the antifreeze starting basic ambient temperature condition is reached according to the antifreeze starting basic ambient temperature; monitoring the antifreeze water pump starting multiple times and monitoring the water flow switch state when the antifreeze starting signal appears according to the antifreeze starting signal; controlling the antifreeze logic state and the compressor start-stop operation to obtain the water flow monitoring antifreeze logic state; the antifreeze water pump starting multiple times includes: the antifreeze water pump starting three times or the antifreeze water pump starting three times or less; monitoring the antifreeze water pump starting multiple times and monitoring the water flow switch state, controlling the antifreeze logic state and the compressor start-stop operation include: monitoring the antifreeze water pump starting multiple times, monitoring the water flow switch state, controlling the antifreeze logic state and the compressor start-stop operation when the antifreeze water pump starts three times or the antifreeze water pump starts three times or less; according to the water flow switch state, if the water flow switch is restored, the normal antifreeze logic state is entered, the antifreeze control first-level antifreeze logic and the antifreeze control second-level antifreeze logic are started; if the water flow switch is not restored, the compressor is started after the antifreeze water pump is started again;

[0074] Monitoring the state of the heat pump unit; through the built-in sensor and monitoring equipment, the working state of the heat pump unit is monitored in real time, including the working frequency of the compressor, the opening of the expansion valve, the running temperature of the unit, etc.; once it is found that the unit appears abnormal, such as the compressor frequency is too high, the expansion valve opening is too large, the unit running temperature is too low, etc., the antifreeze control program is automatically started.

[0075] In one embodiment, S300 includes:

[0076] S301, according to the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state, further monitoring and judging the inlet and outlet water temperature of the unit, and calculating the inlet and outlet water temperature difference;

[0077] S302, judging whether the inlet and outlet water temperature difference is within the normal range of the inlet and outlet water temperature difference and the high pressure protection linkage determination, and determining the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state.

[0078] The principle and effect of the above technical solution are: according to the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state, further monitoring and judging the inlet and outlet water temperature of the unit, and calculating the inlet and outlet water temperature difference; judging whether the inlet and outlet water temperature difference is within the normal range of the inlet and outlet water temperature difference and the high pressure protection linkage determination, and determining the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state; monitoring the water flow switch state; through the water flow switch state monitoring mechanism, the state of the water flow switch is monitored in real time; if the water flow switch is disconnected, the antifreeze protection mode is automatically started; in the antifreeze protection mode, the working state of the water pump is intelligently adjusted according to the current ambient temperature and the outlet water temperature, to prevent the water pump from idling damage or the unit from icing damage;

[0079] The judgment of whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and the high-pressure protection linkage determination, the anti-freezing water pump and compressor linkage control, and the water flow monitoring anti-freezing logic state determination include: collecting the inlet water temperature at the water side heat exchanger end and the outlet water temperature at the water side heat exchanger end through inlet water temperature detection and outlet water temperature detection; comparing the temperature difference between the inlet water temperature at the water side heat exchanger end and the outlet water temperature at the water side heat exchanger end; judging whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and the high-pressure protection linkage determination of the high-pressure switch sensing and the switch state; the high-pressure switch sensing monitors the water flow pressure of the compressor end pipeline, and transmits the water flow pressure signal of the compressor end pipeline to the water temperature high-pressure protection linkage determination module for water temperature high-pressure protection linkage determination; according to the water flow pressure of the compressor end pipeline, whether the water flow pressure of the compressor end pipeline reaches the set compressor end water flow pressure threshold is compared; when the water flow pressure of the compressor end pipeline reaches the set water flow pressure threshold, the high-pressure protection is started; the high-pressure switch receives the determination signal and actively controls the linkage opening and closing circuit; when the high-pressure switch is opened, the active control linkage opening and closing circuit is opened, and the booster pump is started to further increase the water flow pressure; when the water flow pressure of the compressor end pipeline decreases to below the set compressor end water flow pressure threshold, when the high-pressure switch is opened, the active control linkage opening and closing circuit is closed, the booster pump is stopped, and the high-pressure switch is automatically closed; the anti-freezing water pump and compressor linkage control opening and closing and linkage optimization cooperation, and the water flow monitoring anti-freezing logic state determination anti-freezing state and energy consumption state are evaluated, and the high-pressure risk of the freezing environment is evaluated, the linkage determination opening and closing energy consumption optimization and linkage anti-freezing cooperation optimization; significantly improve the anti-freezing protection and greatly reduce the risk.

[0080] In one embodiment, S400 includes:

[0081] S401, according to the anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination, if the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and high-pressure protection does not occur, continue to run the anti-freezing water pump and compressor until the anti-freezing condition is reached, and the anti-freezing state exits; if the temperature difference between the inlet and outlet water exceeds the normal range of the temperature difference between the inlet and outlet water or high-pressure protection occurs, stop the anti-freezing water pump and stop the compressor, and the device as a whole enters the water flow abnormal anti-freezing logic step;

[0082] S402, when entering the water flow abnormal anti-freezing logic step, first do not start the water pump, directly trigger the start of the compressor, and continue until the compressor fails to stop; when the compressor fails to stop, if the anti-freezing condition has not been reached, start the compressor again after 30 minutes, perform compressor anti-freezing operation, and continue until the compressor fails to stop;

[0083] S403, intelligent control of the circulating anti-freezing logic state, continuously circulate the water flow abnormal anti-freezing logic state logic step until the anti-freezing condition is reached, and the anti-freezing state exits; perform low-temperature heat pump anti-freezing intelligent control.

[0084] The principle and effect of the above technical solution are: according to the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state determination, if the inlet and outlet water temperature difference is within the normal range of inlet and outlet water temperature difference and high pressure protection does not occur, the antifreeze water pump and compressor continue to run until the antifreeze condition is reached and the antifreeze state exits; if the inlet and outlet water temperature difference exceeds the normal range of inlet and outlet water temperature difference or high pressure protection occurs, the antifreeze water pump is stopped, and the compressor is stopped, and the device as a whole enters the water flow abnormal antifreeze logic step; when entering the water flow abnormal antifreeze logic step, the water pump is not started first, and the compressor is directly triggered to start until the compressor fails to stop; when the compressor fails to stop, if the antifreeze condition has not been reached, the compressor is started again after 30 minutes, the compressor is run for antifreeze, and the compressor fails to stop until the antifreeze condition is reached and the antifreeze state exits; the antifreeze intelligent control of the low-temperature heat pump is carried out; the antifreeze judgment condition is optimized; according to the real-time monitored ambient temperature and outlet water temperature and the preset antifreeze judgment model, the antifreeze control parameter is intelligently adjusted; this model can more accurately reflect the actual antifreeze demand of the unit, thereby improving the effectiveness of the antifreeze control; intelligent learning; according to the actual effect of each antifreeze control, the antifreeze control parameter is automatically adjusted; for example, if the effect of antifreeze control is not ideal in a certain environment, the antifreeze control parameter is automatically adjusted to adapt to the new environment and working condition; in actual application, the antifreeze logic precision and the antifreeze control process are continuously optimized according to the actual environmental state.

[0085] The application provides an antifreeze control device for a low-temperature heat pump.

[0086] The antifreeze judgment correlation setting module sets antifreeze judgment correlation conditions of antifreeze starting basic ambient temperature and inlet and outlet water temperature difference on the basis of the antifreeze control primary antifreeze logic and the antifreeze control secondary antifreeze logic of the low-temperature heat pump.

[0087] The water pump water flow switch control module controls the starting of the antifreeze water pump according to the antifreeze judgment correlation conditions, monitors and determines the water flow switch state, and controls the starting logic of the antifreeze water pump and the start-stop control of the compressor.

[0088] The water temperature high pressure protection linkage determination module monitors and determines the inlet and outlet water temperature difference and the high pressure protection state of the unit, and determines the antifreeze water pump and compressor linkage control and water flow monitoring antifreeze logic state.

[0089] The cycle antifreeze intelligent control module intelligently controls the cycle antifreeze logic state according to the water flow monitoring antifreeze logic state determination, and controls the antifreeze intelligent control of the low-temperature heat pump.

[0090] The principle and effect of the above technical solution are: the low-temperature heat pump anti-freezing control device provided by the application includes: an anti-freezing judgment correlation setting module, which sets anti-freezing judgment correlation conditions of anti-freezing starting basic ambient temperature and water inlet and outlet temperature difference on the basis of anti-freezing control first-level anti-freezing logic and anti-freezing control second-level anti-freezing logic; a water pump water flow switch control module, which performs anti-freezing water pump starting control according to the anti-freezing judgment correlation conditions, monitors and determines the water flow switch state, and performs anti-freezing water pump starting logic control and compressor start-stop control; a water temperature high-pressure protection linkage determination module, which monitors and determines the water inlet and outlet temperature difference and high-pressure protection state of the unit, performs anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination; a circulating anti-freezing intelligent control module, which intelligently controls the circulating anti-freezing logic state according to the water flow monitoring anti-freezing logic state determination, and performs anti-freezing intelligent control of the low-temperature heat pump; the anti-freezing control method can well avoid anti-freezing failure caused by the disconnection of the water flow switch, can avoid damage of the water pump due to idling, and can avoid freezing damage of the unit due to anti-freezing failure; the anti-freezing control method does not increase the cost of anti-freezing control, and has high cost performance; the application of the anti-freezing control method can greatly reduce the failure rate of the heat pump unit in the use process; the anti-freezing control method and device of the application not only focus on the running state of the heat pump unit based on the ambient temperature and the water outlet temperature, but also make the anti-freezing control more accurate and effective, and can better prevent the heat pump system from icing and protect the normal operation of the heat pump unit; the application can adjust the anti-freezing strategy in time in the case of disconnection of the water flow switch, avoid damage caused by idling of the water pump, and also prevent damage caused by icing of the unit, and realizes comprehensive protection of the heat pump system; the anti-freezing control method and device of the application solve the problems of poor anti-freezing control effect and inability to effectively prevent freezing after the water flow switch is disconnected in the prior art, improve the operation stability and reliability of the heat pump system, and prolong the service life of the heat pump;

[0091] The water flow at the water inlet end passes through the anti-freezing water pump, the water flow at the water inlet end is controlled to be on or off and the water flow at the water inlet end is controlled by controlling the water flow switch at the water inlet end; the water temperature at the water inlet end is detected by the water temperature detector at the water inlet end; the water flow at the water inlet end passes through the water-side heat exchanger to perform the first heat exchange; the water flow after the first heat exchange is introduced into the anti-freezing liquid accumulator; the water flow in the anti-freezing liquid accumulator enters the economizer, a part of the water flow in the economizer is throttled and evaporated into the compressor to perform the compressor compression process adjustment; another part of the water flow in the economizer is introduced into the subsequent pipeline and the evaporator end through the first electronic expansion valve and the second electronic expansion valve; the water flow at the evaporator end is introduced into the gas distribution through the four-way valve, and the water flow after the gas distribution is introduced into the compressor liquid accumulator through the low-pressure switch, and the water flow after the compression of the compressor is collected to the four-way valve through the high-pressure switch; the water flow at the outlet end of the four-way valve is returned to the water-side heat exchanger to perform the second heat exchange; the water temperature after the second heat exchange is detected by the water temperature detector at the water outlet end; the water flow at the water outlet end is controlled to be on or off and the water flow at the water outlet end is controlled by controlling the water flow switch at the water outlet end; the ambient temperature includes the ambient temperature of the water-side heat exchanger, the ambient temperature of the evaporator and the ambient temperature of the accumulator; the ambient temperature of the water-side heat exchanger, the ambient temperature of the evaporator and the ambient temperature of the accumulator are detected by the ambient temperature detector of the water-side heat exchanger, the ambient temperature detector of the evaporator and the ambient temperature detector of the accumulator respectively;

[0092] The anti-freezing liquid accumulator comprises an inner wall of the accumulator, a wall layer inter-electric heating wire net, an outer wall of the accumulator and an accumulator ambient temperature detector; the inner wall of the accumulator is used for storing the water after the first heat exchange; the wall layer inter-electric heating wire net is arranged between the inner wall of the accumulator and the outer wall of the accumulator; the accumulator ambient temperature detector is used for detecting the ambient temperature of the accumulator; when the ambient temperature of the accumulator is lower than the set minimum ambient temperature of the accumulator for anti-freezing, the wall layer inter-electric heating wire net is started to heat, and the water after the first heat exchange in the accumulator is prevented from freezing;

[0093] The anti-freezing judgment and correlation setting module is electrically connected with the water temperature and high-pressure protection linkage judgment module; the water temperature and high-pressure protection linkage judgment module is electrically connected with the water pump water flow switch control module and the circulating anti-freezing intelligent control module respectively; the signal end of the water temperature and high-pressure protection linkage judgment module is electrically connected with the water temperature detector at the water inlet end, the water temperature detector at the water outlet end, the ambient temperature detector of the water-side heat exchanger, the ambient temperature detector of the evaporator and the ambient temperature detector of the accumulator respectively, and collects the pressure signals of the high-pressure switch and the low-pressure switch; the water pump water flow switch control module is electrically connected with and controls the water flow switch at the water outlet end, the water flow switch at the water inlet end, the anti-freezing water pump control end, the compressor control end, the circulating anti-freezing intelligent control module, the four-way valve control end, the first electronic expansion valve and the second electronic expansion valve respectively; the circulating anti-freezing intelligent control module is electrically connected with the evaporator, the four-way valve control end, the compressor control end and the anti-freezing water pump control end respectively.

[0094] In one embodiment, the anti-freezing judgment and correlation setting module comprises:

[0095] The heat pump anti-freezing logic input submodule inputs the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump.

[0096] The anti-freezing start temperature difference setting submodule sets the anti-freezing start basic ambient temperature reaching the anti-freezing condition and sets the water inlet and outlet temperature difference for determining the anti-freezing logic state based on the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic.

[0097] The anti-freezing correlation condition creating submodule creates the anti-freezing judgment correlation condition according to the anti-freezing start basic ambient temperature and the water inlet and outlet temperature difference.

[0098] The principle and effect of the above technical solution are as follows: The anti-freezing judgment correlation setting module includes: the heat pump anti-freezing logic input submodule that inputs the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic of the low-temperature heat pump; the anti-freezing start temperature difference setting submodule that sets the anti-freezing start basic ambient temperature reaching the anti-freezing condition and sets the water inlet and outlet temperature difference for determining the anti-freezing logic state based on the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic; the anti-freezing correlation condition creating submodule that creates the anti-freezing judgment correlation condition according to the anti-freezing start basic ambient temperature and the water inlet and outlet temperature difference; the whole system is initialized, including setting various parameters of the system, such as the ambient temperature threshold, the water outlet temperature threshold, the compressor frequency threshold, and the expansion valve opening threshold; the specific settings of these thresholds need to be adjusted according to the specific model and working environment of the heat pump unit and other factors; the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic respectively count the historical anti-freezing control anti-freezing logic rule to obtain the historical anti-freezing control anti-freezing logic statistical big data; the anti-freezing control judgment condition level is collected according to the anti-freezing control judgment condition level in the historical anti-freezing control anti-freezing logic statistical big data, and the first-level anti-freezing logic and the second-level anti-freezing logic are divided to obtain the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic, and the first-level anti-freezing control and the second-level anti-freezing control are respectively performed according to the first-level anti-freezing logic and the second-level anti-freezing logic.

[0099] In one embodiment, the water pump water flow switch control module includes:

[0100] The ambient temperature anti-freezing judgment submodule determines the anti-freezing start basic ambient temperature according to the anti-freezing judgment correlation condition.

[0101] The anti-freezing start signal triggering submodule triggers the anti-freezing start signal when the anti-freezing start basic ambient temperature condition is reached according to the anti-freezing start basic ambient temperature.

[0102] The water pump switch monitoring control submodule monitors the number of times of starting of the anti-freezing water pump and monitors the water flow switch state according to the anti-freezing start signal, controls the anti-freezing logic state and the start-stop operation of the compressor, and obtains the water flow monitoring anti-freezing logic state.

[0103] The number of times of starting of the anti-freezing water pump includes three times of starting of the anti-freezing water pump or less than three times of starting of the anti-freezing water pump.

[0104] The monitoring of the number of times of starting of the anti-freezing water pump and the monitoring of the water flow switch state, the control of the anti-freezing logic state and the start-stop operation of the compressor include: monitoring the number of times of starting of the anti-freezing water pump, monitoring the water flow switch state, controlling the anti-freezing logic state and the start-stop operation of the compressor when the number of times of starting of the anti-freezing water pump is three times or less than three times; according to the water flow switch state, if the water flow switch is restored, entering the normal anti-freezing logic state, starting the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic; if the water flow switch is not restored, starting the compressor after starting the anti-freezing water pump again.

[0105] The principle and effect of the above technical solution are: the water pump water flow switch control module includes: an environment temperature anti-freezing judgment submodule that determines the anti-freezing start basic environment temperature according to the anti-freezing judgment associated condition; an anti-freezing start signal triggering submodule that triggers the anti-freezing start signal according to the anti-freezing start basic environment temperature when the anti-freezing start basic environment temperature condition is reached; a water pump switch monitoring control submodule that monitors the number of times of starting of the anti-freezing water pump and monitors the water flow switch state according to the anti-freezing start signal when the anti-freezing start signal appears, controls the anti-freezing logic state and the start-stop operation of the compressor, and obtains the water flow monitoring anti-freezing logic state; the number of times of starting of the anti-freezing water pump includes three times of starting of the anti-freezing water pump or less than three times of starting of the anti-freezing water pump; the monitoring of the number of times of starting of the anti-freezing water pump and the monitoring of the water flow switch state, the control of the anti-freezing logic state and the start-stop operation of the compressor include: monitoring the number of times of starting of the anti-freezing water pump, monitoring the water flow switch state, controlling the anti-freezing logic state and the start-stop operation of the compressor when the number of times of starting of the anti-freezing water pump is three times or less than three times; according to the water flow switch state, if the water flow switch is restored, entering the normal anti-freezing logic state, starting the anti-freezing control first-level anti-freezing logic and the anti-freezing control second-level anti-freezing logic; if the water flow switch is not restored, starting the compressor after starting the anti-freezing water pump again; monitoring the heat pump unit state; through the built-in sensor and monitoring equipment, the working state of the heat pump unit is monitored in real time, including the working frequency of the compressor, the opening of the expansion valve, the operating temperature of the unit, etc.; once it is found that the unit appears abnormal, such as the frequency of the compressor is too high, the opening of the expansion valve is too large, the operating temperature of the unit is too low, etc., the anti-freezing control program is automatically started.

[0106] In one embodiment, the water temperature high pressure protection linkage determination module includes:

[0107] The water temperature difference of the unit operation sub-module further monitors and judges the inlet and outlet water temperatures of the unit and calculates the inlet and outlet water temperature difference according to the antifreezing water pump and compressor linkage control and water flow monitoring antifreezing logic state.

[0108] The linkage control antifreezing logic judgment sub-module judges whether the inlet and outlet water temperature difference is within the normal range of the inlet and outlet water temperature difference and the high-pressure protection linkage judgment, and judges the antifreezing water pump and compressor linkage control and water flow monitoring antifreezing logic state.

[0109] The principle and effect of the above technical solution are as follows: the water temperature high-pressure protection linkage judgment module comprises: the water temperature difference of the unit operation sub-module further monitors and judges the inlet and outlet water temperatures of the unit and calculates the inlet and outlet water temperature difference according to the antifreezing water pump and compressor linkage control and water flow monitoring antifreezing logic state; the linkage control antifreezing logic judgment sub-module judges whether the inlet and outlet water temperature difference is within the normal range of the inlet and outlet water temperature difference and the high-pressure protection linkage judgment, and judges the antifreezing water pump and compressor linkage control and water flow monitoring antifreezing logic state; the water flow switch state is monitored; the water flow switch state is monitored in real time through the water flow switch state monitoring mechanism; if the water flow switch is monitored to be turned off, the antifreezing protection mode is automatically started; in the antifreezing protection mode, the working state of the water pump is intelligently adjusted according to the current environmental temperature and the outlet water temperature, so as to prevent the water pump from being damaged by idling or the unit from being damaged by icing;

[0110] The judgment of whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and the high-pressure protection linkage determination, the anti-freezing water pump and compressor linkage control, and the water flow monitoring anti-freezing logic state determination include: collecting the inlet water temperature at the water side heat exchanger end and the outlet water temperature at the water side heat exchanger end through inlet water temperature detection and outlet water temperature detection; comparing the temperature difference between the inlet water temperature at the water side heat exchanger end and the outlet water temperature at the water side heat exchanger end; judging whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and the high-pressure protection linkage determination of the high-pressure switch sensing and the switch state; the high-pressure switch sensing monitors the water flow pressure of the compressor end pipeline, and transmits the water flow pressure signal of the compressor end pipeline to the water temperature high-pressure protection linkage determination module for water temperature high-pressure protection linkage determination; according to the water flow pressure of the compressor end pipeline, whether the water flow pressure of the compressor end pipeline reaches the set compressor end water flow pressure threshold is compared; when the water flow pressure of the compressor end pipeline reaches the set water flow pressure threshold, the high-pressure protection is started; the high-pressure switch simultaneously receives the determination signal and actively controls the linkage opening and closing circuit; when the high-pressure switch is opened, the active control linkage opening and closing circuit is opened, and the booster pump is started to further increase the water flow pressure; when the water flow pressure of the compressor end pipeline decreases to below the set compressor end water flow pressure threshold, when the high-pressure switch is opened, the active control linkage opening and closing circuit is closed, the booster pump is stopped, and the high-pressure switch is automatically closed; the anti-freezing water pump and compressor linkage control opening and closing and linkage optimization cooperation, and the water flow monitoring anti-freezing logic state determination anti-freezing state and energy consumption state are evaluated, and the high-pressure risk of the freezing environment is evaluated, the linkage determination opening and closing energy consumption optimization and linkage anti-freezing cooperation optimization; significantly improve the anti-freezing protection and greatly reduce the risk.

[0111] In one embodiment, the circulating anti-freezing intelligent control module comprises:

[0112] The linkage operation abnormality analysis submodule, according to the anti-freezing water pump and compressor linkage control and water flow monitoring anti-freezing logic state determination, if the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and high-pressure protection does not occur, the anti-freezing water pump and compressor continue to run until the anti-freezing condition is reached and the anti-freezing state is exited; if the temperature difference between the inlet and outlet water exceeds the normal range of the temperature difference between the inlet and outlet water or high-pressure protection occurs, the anti-freezing water pump is stopped, and the compressor is stopped, and the device as a whole enters the water flow abnormality anti-freezing logic step;

[0113] The water flow abnormality anti-freezing operation submodule, when entering the water flow abnormality anti-freezing logic step, the water pump is not started, and the compressor is directly started until the compressor fails to stop; when the compressor fails to stop, if the anti-freezing condition has not been reached, the compressor is started again after 30 minutes, the compressor anti-freezing operation is performed, and the compressor fails to stop until the compressor fails to stop;

[0114] The intelligent control cycle anti-freezing sub-module, the intelligent control cycle anti-freezing logic state, the continuous cycle water flow abnormal anti-freezing logic state logic step, until the anti-freezing condition is reached, and the anti-freezing state is exited.

[0115] The principle and effect of the above technical solution are as follows: the cycle anti-freezing intelligent control module comprises: a linkage operation abnormality analysis sub-module, according to the linkage control of the anti-freezing water pump and the compressor and the water flow monitoring anti-freezing logic state, if the inlet and outlet water temperature difference is within the normal range of the inlet and outlet water temperature difference and high pressure protection does not occur, the anti-freezing water pump and the compressor continue to operate, until the anti-freezing condition is reached, and the anti-freezing state is exited; if the inlet and outlet water temperature difference exceeds the normal range of the inlet and outlet water temperature difference or high pressure protection occurs, the anti-freezing water pump is stopped, and the compressor is also stopped, and the whole device enters the water flow abnormal anti-freezing logic step; a water flow abnormal anti-freezing operation sub-module, when the water flow abnormal anti-freezing logic step is entered, the water pump is not started first, and the compressor is directly started, until the compressor fails to stop; when the compressor fails to stop, if the anti-freezing condition is not reached, the compressor is started again after 30 minutes, the anti-freezing operation of the compressor is performed, until the compressor fails to stop; the intelligent control cycle anti-freezing sub-module, the intelligent control cycle anti-freezing logic state, the continuous cycle water flow abnormal anti-freezing logic state logic step, until the anti-freezing condition is reached, and the anti-freezing state is exited; the anti-freezing intelligent control of the low-temperature heat pump is performed.

[0116] The anti-freezing judgment condition is optimized; according to the real-time monitored environment temperature and outlet water temperature and the preset anti-freezing judgment model, the anti-freezing control parameter is intelligently adjusted; this model can more accurately reflect the actual anti-freezing demand of the unit, thereby improving the effectiveness of the anti-freezing control; intelligent learning; according to the actual effect of each anti-freezing control, the anti-freezing control parameter is automatically adjusted; for example, if the effect of the anti-freezing control is not ideal in a certain environment, the anti-freezing control parameter is automatically adjusted to adapt to the new environment and working condition; in actual application, according to the actual environment state, the anti-freezing logic precision and the anti-freezing control process are continuously adjusted and optimized.

[0117] Although the embodiments of the present application have been disclosed as above, they are not limited to the application listed in the specification and the embodiments, and can be applied to various fields suitable for the present application, and additional modifications can be easily realized by those skilled in the art, and therefore the present application is not limited to specific details and the figures shown and described herein, without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A method for preventing freezing in a low-temperature heat pump, characterized in that, include: S100, based on the first-level antifreeze control logic and the second-level antifreeze control logic of the low-temperature heat pump, sets the antifreeze judgment correlation conditions of the basic ambient temperature for antifreeze start and the temperature difference between inlet and outlet water. S200 controls the start of the antifreeze water pump based on the antifreeze judgment association conditions, monitors and judges the status of the water flow switch, and performs antifreeze water pump start logic control and compressor start / stop control. S300 monitors and judges the temperature difference between the inlet and outlet water of the unit and the high-pressure protection status, performs linkage control of the antifreeze water pump and compressor and water flow monitoring and antifreeze logic status determination. S400 intelligently controls the cyclic antifreeze logic state based on water flow monitoring and antifreeze logic state, and performs intelligent antifreeze control of the low-temperature heat pump. The S300 includes: S301, based on the linkage control of the antifreeze water pump and compressor and the antifreeze logic status of water flow monitoring, further monitors and judges the inlet and outlet water temperatures of the unit, and calculates the inlet and outlet water temperature difference; S302, determine whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and determine the high pressure protection linkage, and perform linkage control of the antifreeze water pump and compressor and water flow monitoring antifreeze logic status determination. The S400 includes: S401, based on the linkage control of the antifreeze water pump and compressor and the water flow monitoring antifreeze logic status determination, if the inlet and outlet water temperature difference is within the normal range and no high pressure protection occurs, the antifreeze water pump and compressor continue to run until the antifreeze exit condition is met, and the antifreeze state exits; if the inlet and outlet water temperature difference exceeds the normal range or high pressure protection occurs, the antifreeze water pump and compressor are stopped, and the entire device enters the water flow abnormal antifreeze logic step. S402, when entering the water flow abnormal antifreeze logic step, do not start the water pump first, directly trigger the start of the compressor until the compressor fails and stops; when the compressor fails and stops, if the antifreeze exit condition has not been met, the compressor will be restarted after 30 minutes to perform compressor antifreeze operation until the compressor fails and stops. S403, intelligent control of the cyclic antifreeze logic state, continuously circulating water flow abnormal antifreeze logic state logic steps until the antifreeze exit condition is reached, and the antifreeze state exits; to perform intelligent antifreeze control of low temperature heat pump.

2. The antifreeze control method for a low-temperature heat pump according to claim 1, characterized in that, S100 includes: S101, input the first-level antifreeze control logic and the second-level antifreeze control logic of the low-temperature heat pump; S102, based on the first-level antifreeze control logic and the second-level antifreeze control logic, sets the basic ambient temperature for antifreeze start when the antifreeze condition is met, and sets the inlet and outlet water temperature difference for water flow to determine the antifreeze logic status. S103, establish the correlation conditions for antifreeze judgment based on the basic ambient temperature for antifreeze start-up and the temperature difference between inlet and outlet water.

3. The antifreeze control method for a low-temperature heat pump according to claim 1, characterized in that, S200 includes: S201, determine the basic ambient temperature for antifreeze activation based on the antifreeze judgment association conditions; S202, based on the basic ambient temperature for antifreeze start, when the basic ambient temperature condition for antifreeze start is reached, the antifreeze start signal is triggered; S203, based on the antifreeze start signal, when the antifreeze start signal appears, monitor the antifreeze water pump to start multiple times, monitor the water flow switch status, control the antifreeze logic status and compressor start / stop operation, and obtain the water flow monitoring antifreeze logic status. Multiple starts of the antifreeze water pump include: the antifreeze water pump being started three times or less; Monitoring the multiple starts of the antifreeze water pump and monitoring the status of the flow switch, controlling the antifreeze logic status and compressor start / stop operation includes: monitoring the multiple starts of the antifreeze water pump; when the antifreeze water pump starts three times or less, monitoring the status of the flow switch and controlling the antifreeze logic status and compressor start / stop operation; based on the status of the flow switch, if the flow switch recovers, the normal antifreeze logic state is entered, and the first-level antifreeze logic and the second-level antifreeze logic are activated; if the flow switch does not recover, the antifreeze water pump is restarted and then the compressor is started.

4. A freeze protection control device for a low-temperature heat pump, characterized in that, An apparatus employing the antifreeze control method for a low-temperature heat pump as described in claim 1, comprising: The antifreeze judgment association setting module sets the antifreeze judgment association conditions based on the first-level antifreeze logic and the second-level antifreeze logic of the low-temperature heat pump, namely the basic ambient temperature for antifreeze start and the temperature difference between the inlet and outlet water. The water pump flow switch control module controls the start of the antifreeze water pump based on the antifreeze judgment associated conditions, monitors and judges the status of the flow switch, and performs antifreeze water pump start logic control and compressor start / stop control. The water temperature and high pressure protection linkage judgment module monitors and judges the temperature difference between the inlet and outlet water of the unit and the high pressure protection status, performs linkage control of the antifreeze water pump and compressor and water flow monitoring and antifreeze logic status judgment. The circulating antifreeze intelligent control module determines the antifreeze logic state based on water flow monitoring, and then intelligently controls the circulating antifreeze logic state to perform antifreeze intelligent control of the low-temperature heat pump. The water temperature and high pressure protection linkage judgment module includes: The unit water temperature difference calculation submodule further monitors and judges the inlet and outlet water temperatures of the unit based on the linkage control of the antifreeze water pump and compressor and the antifreeze logic status of water flow monitoring, and calculates the inlet and outlet water temperature difference. The linkage control antifreeze logic judgment submodule determines whether the temperature difference between the inlet and outlet water is within the normal range of the temperature difference between the inlet and outlet water and performs high pressure protection linkage judgment, performs linkage control of the antifreeze water pump and compressor and water flow monitoring antifreeze logic status judgment. The intelligent control module for cyclic antifreeze includes: The linkage operation anomaly analysis submodule determines the antifreeze logic status based on the linkage control of the antifreeze water pump and compressor and water flow monitoring. If the inlet and outlet water temperature difference is within the normal range and no high pressure protection occurs, the antifreeze water pump and compressor continue to run until the antifreeze exit condition is met, and the antifreeze state exits. If the inlet and outlet water temperature difference exceeds the normal range or high pressure protection occurs, the antifreeze water pump and compressor are stopped, and the entire device enters the water flow anomaly antifreeze logic step. When the abnormal water flow antifreeze operation submodule enters the abnormal water flow antifreeze logic step, it will not start the water pump first, but directly trigger the start of the compressor until the compressor fails and stops; when the compressor fails and stops, if the conditions for exiting antifreeze have not been met, the compressor will be restarted after 30 minutes to perform compressor antifreeze operation until the compressor fails and stops. The intelligent control circulation antifreeze submodule controls the circulation antifreeze logic state, continuously circulating water flow abnormal antifreeze logic state steps until the antifreeze exit condition is reached, and the antifreeze state exits; it performs intelligent antifreeze control of low temperature heat pump.

5. The antifreeze control device for a low-temperature heat pump according to claim 4, characterized in that, The antifreeze detection and association settings module includes: The heat pump antifreeze logic input submodule is used to input the primary antifreeze control logic and the secondary antifreeze control logic of the low-temperature heat pump. The antifreeze start temperature difference setting submodule is based on the first-level antifreeze control logic and the second-level antifreeze control logic. It sets the basic ambient temperature for antifreeze start to meet the antifreeze conditions and sets the inlet and outlet water temperature difference for water flow to determine the antifreeze logic status. The submodule for creating antifreeze association conditions establishes antifreeze judgment association conditions based on the basic ambient temperature for antifreeze startup and the temperature difference between inlet and outlet water.

6. The antifreeze control device for a low-temperature heat pump according to claim 4, characterized in that, The water pump flow switch control module includes: The ambient temperature antifreeze judgment submodule determines the basic ambient temperature for antifreeze activation based on the antifreeze judgment association conditions. The anti-freeze start signal triggering submodule triggers the anti-freeze start signal when the basic ambient temperature for anti-freeze start is reached. The water pump switch monitoring and control submodule monitors the start of the antifreeze water pump multiple times based on the antifreeze start signal, monitors the water flow switch status, controls the antifreeze logic status and compressor start / stop operation, and obtains the water flow monitoring antifreeze logic status. Multiple starts of the antifreeze water pump include: the antifreeze water pump being started three times or less; Monitoring the multiple starts of the antifreeze water pump and monitoring the status of the flow switch, controlling the antifreeze logic status and compressor start / stop operation includes: monitoring the multiple starts of the antifreeze water pump; when the antifreeze water pump starts three times or less, monitoring the status of the flow switch and controlling the antifreeze logic status and compressor start / stop operation; based on the status of the flow switch, if the flow switch recovers, the normal antifreeze logic state is entered, and the first-level antifreeze logic and the second-level antifreeze logic are activated; if the flow switch does not recover, the antifreeze water pump is restarted and then the compressor is started.

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