Heat pump unit control method, device and equipment and storage medium

Abstract

The embodiment of the invention discloses a heat pump unit control method and device, equipment and a storage medium, and the method comprises the steps that when the environment temperature is within the preset ultralow temperature range, a compressor is controlled to operate at the first starting frequency; after the compressor operates for a first preset duration, the water inlet temperature is detected in real time, and when the water inlet temperature exceeds a first threshold value, the opening degree of a main path electronic expansion valve is adjusted to a first opening degree; the heat pump unit is controlled to operate according to a preset first control strategy, the first control strategy takes the first frequency as the lowest operation frequency, the first frequency is larger than the lowest operation frequency corresponding to a second control strategy, the first opening degree is smaller than the initial opening degree corresponding to the second control strategy, and the second control strategy is a control strategy corresponding to a preset normal temperature range. The temperature value in the normal temperature range is higher than the temperature value in the ultralow temperature range, the technical problem that the operation reliability is low in the ultralow temperature environment can be solved, and the operation reliability and stability of the heat pump unit in the ultralow temperature environment are improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of heat pump control technology, and in particular, to a heat pump unit control method, device, equipment and storage medium. Background Art

[0002] As a highly efficient heat energy conversion device, air source heat pump units are widely used in heating and hot water supply.

[0003] When heating and hot water are supplied, it is usually due to relatively cold weather. In ultra-low temperature environments, traditional air source heat pump units often experience unstable operation when controlled. Especially when the inlet water temperature is high, the exhaust gas may not be stably controlled and will continue to rise, and the compressor will continue to reduce the frequency, causing the heat pump unit to circulate without heating capacity; and after the compressor continues to reduce to the preset minimum operating frequency, it will also cause the compressor to be unable to return oil.

[0004] Therefore, when the existing heat pump unit performs heating control in an ultra-low temperature environment, the operating reliability is low. Summary of the invention

[0005] The embodiments of the present application provide a heat pump unit control method, device, equipment and storage medium, which can solve the technical problem of low operating reliability of the heat pump unit control in an ultra-low temperature environment, and improve the operating reliability and stability of the heat pump unit in an ultra-low temperature environment.

[0006] In a first aspect, an embodiment of the present application provides a heat pump unit control method, comprising:

[0007] receiving a start instruction, and detecting an ambient temperature in response to the start instruction;

[0008] When the ambient temperature is within a preset ultra-low temperature range, the compressor is controlled to operate at a first starting frequency;

[0009] After the compressor runs for a first preset time, the water inlet temperature is detected in real time, and when the water inlet temperature exceeds a first threshold, the opening of the main electronic expansion valve is adjusted to a first opening;

[0010] The operation of the heat pump unit is controlled according to a preset first control strategy. The first control strategy uses the first frequency as the minimum operating frequency. The first frequency is greater than the minimum operating frequency corresponding to the second control strategy. The first opening is less than the initial opening corresponding to the second control strategy. The second control strategy is a control strategy corresponding to a preset normal temperature range. The temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

[0011] In one embodiment, after the compressor runs for a first preset time, the method includes:

[0012] Real-time detection of water temperature and acquisition of target water temperature;

[0013] Determine the target frequency value according to the outlet water temperature and ambient temperature;

[0014] When the difference between the target water temperature and the outlet water temperature is below the second threshold, the compressor is controlled to perform frequency increase processing at a first frequency increase speed until the target frequency value is reached.

[0015] In one embodiment, after determining the target frequency value according to the outlet water temperature and the ambient temperature, the following steps are performed:

[0016] When the difference between the target water temperature and the outlet water temperature exceeds the second threshold, the compressor is controlled to perform frequency increase processing at the second frequency increase speed until the difference between the target water temperature and the outlet water temperature is below the second threshold, and the compressor is controlled to perform frequency increase processing at the first frequency increase speed until the target frequency value is reached.

[0017] In one embodiment, after the inlet water temperature is detected in real time, the following steps are included:

[0018] When the inlet water temperature is below the first threshold, the opening of the main electronic expansion valve is adjusted to a second opening, and the operation of the heat pump unit is controlled according to the preset first control strategy, and the second opening is greater than the initial opening.

[0019] In one embodiment, controlling the operation of the heat pump unit according to a preset first control strategy includes:

[0020] Obtain the current exhaust gas superheat, return gas superheat and target water temperature of the heat pump unit;

[0021] According to the exhaust gas superheat, return gas superheat and target water temperature, the operation of the heat pump unit is controlled according to the preset first control strategy, and the preset PID control strategy is executed to adjust the operating frequency of the compressor and the opening of the valve in the heat pump unit, and the valve includes a main electronic expansion valve and an enthalpy increase electronic expansion valve.

[0022] In one embodiment, after receiving a start instruction and detecting the ambient temperature in response to the start instruction, the method includes:

[0023] When the ambient temperature is within the preset normal temperature range, the compressor is controlled to operate at the preset starting frequency;

[0024] After the compressor runs for a second preset time, adjusting the opening of the main electronic expansion valve to an initial opening;

[0025] The operation of the heat pump unit is controlled according to the preset second control strategy.

[0026] In one embodiment, after receiving a start instruction and detecting the ambient temperature in response to the start instruction, the method includes:

[0027] The outlet water temperature is detected in real time, and when the outlet water temperature exceeds a third threshold, the compressor is controlled to operate at the first frequency.

[0028] In a second aspect, an embodiment of the present application provides a heat pump unit control device, comprising:

[0029] The command response module is used to receive a start command, and detect the ambient temperature in response to the start command;

[0030] A low-temperature starting module, used to control the compressor to operate at a first starting frequency when the ambient temperature is within a preset ultra-low temperature range;

[0031] A first adjustment module is used to detect the inlet water temperature in real time after the compressor runs for a first preset time, and when the inlet water temperature exceeds a first threshold, adjust the opening of the main electronic expansion valve to a first opening;

[0032] The first control strategy execution module is used to control the operation of the heat pump unit according to a preset first control strategy. The first control strategy uses a first frequency as the minimum operating frequency. The first frequency is greater than the minimum operating frequency corresponding to the second control strategy. The first opening is less than the initial opening corresponding to the second control strategy. The second control strategy is a control strategy corresponding to a preset normal temperature range. The temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

[0033] In a third aspect, an embodiment of the present application provides a heat pump unit control device, including:

[0034] memory and one or more processors;

[0035] The memory is used to store one or more programs;

[0036] When the one or more programs are executed by the one or more processors, the one or more processors implement the heat pump unit control method as described in the first aspect.

[0037] In a fourth aspect, an embodiment of the present application provides a storage medium storing computer executable instructions, which, when executed by a computer processor, are used to execute the heat pump unit control method as described in the first aspect.

[0038] After the heat pump unit is started by the embodiment of the present application, when the ambient temperature is within the preset ultra-low temperature range, the compressor is controlled to operate at the first starting frequency for a first preset time. When the inlet water temperature exceeds the first threshold, the opening of the main electronic expansion valve is adjusted to the first opening, and the operation of the heat pump unit is controlled according to the preset first control strategy, wherein the first control strategy uses the first frequency as the minimum operating frequency, the first frequency is greater than the initial opening corresponding to the second control strategy of the preset normal temperature range, and the temperature value of the normal temperature range is higher than the temperature value of the ultra-low temperature range. By adopting the above technical means, when the ambient temperature is within the ultra-low temperature range, the minimum operating frequency of the heat pump unit is increased to the first frequency, so as to avoid the problem of the heat pump unit being unable to return oil due to the operation of the heat pump unit at a lower minimum operating frequency in an ultra-low temperature environment. By increasing the minimum operating frequency of the heat pump unit to the first frequency, the present embodiment allows the heat pump unit to return oil better in an ultra-low temperature environment, thereby improving the operating reliability and stability of the heat pump unit. In addition, when the ambient temperature is within the ultra-low temperature range, the opening of the main electronic expansion valve is reduced to reduce the refrigerant flow rate and prevent the refrigerant and oil mixture from rushing out of the compressor in large quantities, thereby avoiding problems caused by too little oil in the compressor and further improving the operating reliability and stability of the heat pump unit.

[0039] The beneficial effects of the heat pump unit control device, heat pump unit control equipment and storage medium provided above can refer to the beneficial effects of the heat pump unit control method. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a structural schematic diagram of a heat pump unit provided in an embodiment of the present application;

[0041] Figure 2 is a flow chart of a heat pump unit control method provided in an embodiment of the present application;

[0042] Figure 3 It is a structural schematic diagram of a heat pump unit control device provided in an embodiment of the present application;

[0043] Figure 4 It is a structural schematic diagram of a heat pump unit control device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical scheme and advantages of the present application clearer, the specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. It is understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for the convenience of description, only the part related to the present application but not all the contents are shown in the accompanying drawings. Before discussing the exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow chart describes each operation (or step) as a sequential process, many of the operations therein can be implemented in parallel, concurrently or simultaneously. In addition, the order of each operation can be rearranged. The process can be terminated when its operation is completed, but it can also have additional steps not included in the accompanying drawings. The process can correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.

[0045] As a highly efficient heat energy conversion device, air source heat pump units are widely used in heating and hot water supply. Heating and hot water supply are usually in relatively cold weather. In ultra-low temperature environments, traditional air source heat pump units often experience unstable operation when controlled. When the heat pump unit is just turned on, in the case of low water temperature inlet, if the electronic expansion valve is adjusted according to the initial opening within the normal temperature range and the compressor operation is controlled according to the starting frequency within the normal temperature range, the system low pressure will be too low at the moment of initial opening. In addition, when the inlet water temperature is high, the exhaust gas may not be stably controlled and will continue to rise, and the compressor will continue to reduce the frequency, resulting in the heat pump unit circulating without heating capacity; and after the compressor continues to reduce to the preset minimum operating frequency, it will also cause problems such as the compressor being unable to return oil, the system circulation volume being too low, and the exhaust gas overheating.

[0046] Based on this, a heat pump unit control method, device, equipment and storage medium of an embodiment of the present application are provided, which is intended to increase the minimum operating frequency of the heat pump unit to the first frequency when the heat pump unit is started and the ambient temperature is within the ultra-low temperature range, so as to avoid the problem of the heat pump unit being unable to return oil due to the operation of the heat pump unit at a lower minimum operating frequency in an ultra-low temperature environment. This embodiment increases the minimum operating frequency of the heat pump unit to the first frequency, so that the heat pump unit can return oil better in an ultra-low temperature environment, thereby improving the operational reliability and stability of the heat pump unit. In addition, when the ambient temperature is within the ultra-low temperature range, the opening of the main electronic expansion valve is reduced to reduce the refrigerant flow rate and avoid a large amount of the mixture of refrigerant and oil rushing out of the compressor, thereby avoiding problems caused by too low oil in the compressor, and further improving the operational reliability and stability of the heat pump unit.

[0047] Figure 1 is a schematic diagram of the structure of a heat pump unit provided in an embodiment of the present application, referring to Figure 1The heat pump unit includes a compressor 10, a four-way valve 20, a shell and tube heat exchanger 30, a gas-liquid separator 40, a fin heat exchanger 50, an economizer 60, an enthalpy-increasing electronic expansion valve 70, a main electronic expansion valve 80, a water temperature sensor (not shown in the figure) and a heat pump unit control device (not shown in the figure). The exhaust port of the compressor 10 is connected to the input port of the shell and tube heat exchanger 30, the input port of the gas-liquid separator 40 and the output port of the fin heat exchanger 50 through the four-way valve 20. The output port of the shell and tube heat exchanger 30 is connected to the first input port of the economizer 60, and the second input port of the economizer 60 is connected to the first port of the enthalpy-increasing electronic expansion valve 70. The first output port of the economizer 60 is connected to the second port of the enthalpy-increasing electronic expansion valve 70 and the first port of the main electronic expansion valve 80, and the second output port of the economizer 60 is connected to the enthalpy-increasing port of the compressor 10. The second port of the main electronic expansion valve 80 is connected to the input port of the fin heat exchanger 50. The output port of the gas-liquid separator 40 is connected to the air intake port of the compressor 10. The heat pump unit control device is connected to the compressor 10, the main electronic expansion valve 80 and the enthalpy increase electronic expansion valve 70. The heat pump unit also includes an environmental sensor 501; the environmental sensor 501 is arranged on the fin heat exchanger 50, and the environmental sensor 501 is used to detect the ambient temperature. The heat pump unit control device is used to execute the heat pump unit control method provided in this embodiment.

[0048] Figure 2 A flow chart of a heat pump unit control method provided in an embodiment of the present application is given. The heat pump unit control method provided in this embodiment can be executed by a heat pump unit control device, which can be implemented by software and / or hardware. The heat pump unit control device can be composed of two or more physical entities, or can be composed of one physical entity. Generally speaking, the heat pump unit control device can be a terminal device, such as a computer, an interactive tablet, a tablet computer, a smart TV, a learning machine, a mobile phone, a remote control, or other terminal devices.

[0049] The following description is made by taking a computer as the main body of the heat pump unit control method as an example. Figure 1 The heat pump unit control method is used for the aforementioned heat pump unit, and the heat pump unit control method specifically includes:

[0050] S101, receiving a start instruction, and detecting an ambient temperature in response to the start instruction.

[0051] When the heat pump unit is turned on, it receives a start-up instruction, responds to the start-up instruction, detects the ambient temperature, and executes a corresponding control strategy according to the detected ambient temperature range. Exemplarily, the temperature detection is performed by the aforementioned environmental sensor 501.

[0052] The ambient temperature is divided into an ultra-low temperature range and a normal temperature range, for example, the ultra-low temperature range is an ambient temperature below -20° C., and the normal temperature range is an ambient temperature above -20° C. The specific values ​​of the ultra-low temperature range and the normal temperature range can be set according to actual conditions, and this embodiment does not limit them.

[0053] S102: When the ambient temperature is within a preset ultra-low temperature range, the compressor is controlled to operate at a first starting frequency.

[0054] When the ambient temperature is within the preset normal temperature range, the compressor is controlled to operate at a preset starting frequency. When it is detected that the ambient temperature is within the preset ultra-low temperature range, the compressor is controlled to operate at a first starting frequency, and the first starting frequency is greater than the preset starting frequency. In the above, when the ambient temperature is within the ultra-low temperature range, the compressor is controlled to start operating at a higher first starting frequency. Compared with the preset starting frequency corresponding to the ambient temperature within the normal temperature range, the higher first starting frequency can increase the oil temperature in the compressor faster, thereby avoiding a large amount of refrigerant and oil mixture from rushing out of the compressor due to the low temperature environment. In this embodiment, the compressor is controlled to start operating at a higher first starting frequency, so that the oil temperature in the compressor rises rapidly, and the separation of the refrigerant and the oil is achieved faster, thereby reducing the oil outflow, thereby improving the stability and reliability of the start-up operation of the heat pump unit. In addition, by starting and operating the compressor at a higher first starting frequency, the problem of excessive starting load and excessive exhaust gas of the compressor in an ultra-low temperature environment can be avoided, further improving the stability and reliability of the start-up operation of the heat pump unit.

[0055] S103: After the compressor runs for a first preset time, detect the water inlet temperature in real time, and when the water inlet temperature exceeds a first threshold, adjust the opening of the main electronic expansion valve to a first opening.

[0056] When it is detected that the ambient temperature is within the preset ultra-low temperature range, the compressor is controlled to operate at the first starting frequency, and the first starting frequency is continuously used for the first preset time. This is the start-up phase of the heat pump unit, and it is first operated at the first starting frequency for a period of time. After the compressor is controlled to operate at the first starting frequency for the first preset time, the inlet water temperature is detected in real time to adjust the opening of the main electronic expansion valve according to the inlet water temperature. The inlet water temperature can be detected in real time by the water temperature sensor in the heat pump unit. When the inlet water temperature exceeds the first threshold, the opening of the main electronic expansion valve is adjusted to the first opening, wherein the first opening is less than the initial opening of the second control strategy within the preset normal temperature range. By reducing the opening of the main electronic expansion valve, it is possible to prevent the heat-added air-supply branch from failing to obtain liquid refrigerant, which would cause the system exhaust to be too high, thereby causing the operating frequency of the compressor to decrease and failing to achieve the corresponding heating capacity. Therefore, the opening of the main electronic expansion valve is adjusted to the first opening to increase the amount of refrigerant obtained by the heat-added air-supply branch, thereby improving the operating stability and reliability of the heat pump unit, thereby improving the heating effect of the heat pump unit.

[0057] For example, assuming that the preset initial opening is N1, the first opening is set to N high =N1-N0, where N0 is the preset opening parameter. By setting a first opening lower than the initial opening at ultra-low ambient temperature, it can ensure that the main flow volume is small during heating, so that more refrigerant flows through the enthalpy increase circuit, which can effectively reduce the exhaust temperature and improve the system capacity.

[0058] S104. Control the operation of the heat pump unit according to a preset first control strategy. The first control strategy uses a first frequency as the minimum operating frequency. The first frequency is greater than the minimum operating frequency corresponding to the second control strategy. The first opening is less than an initial opening corresponding to the second control strategy. The second control strategy is a control strategy corresponding to a preset normal temperature range. The temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

[0059] After the compressor runs for a first preset time, the heat pump unit is controlled to run according to a preset first control strategy, wherein the first control strategy corresponds to a control strategy for an ultra-low temperature range, and the second control strategy corresponds to a control strategy for a preset normal temperature range, and the temperature value in the normal temperature range is higher than the temperature value in the ultra-low temperature range. The first control strategy uses the first frequency as the minimum operating frequency, and the first frequency is greater than the minimum operating frequency corresponding to the second control strategy. The aforementioned first opening is less than the initial opening corresponding to the second control strategy.

[0060] Exemplarily, it is assumed that the minimum operating frequency corresponding to the second control strategy is 50 Hz, and the first frequency is set to 55 Hz.

[0061] When the ambient temperature is within the ultra-low temperature range, the compressor operation is controlled according to the first control strategy, so that the heat pump unit can control the operation of the compressor based on a higher minimum operating frequency (i.e., the first frequency), thereby ensuring that the system has sufficient circulation volume, and avoiding insufficient system circulation volume due to a lower minimum operating frequency (i.e., the preset minimum operating frequency corresponding to the normal temperature range). Therefore, the operation of the compressor is controlled with the first frequency as the minimum operating frequency. Based on the sufficient system circulation volume, it can be ensured that the enthalpy increase branch can obtain liquid refrigerant, and the exhaust temperature can be lowered by increasing enthalpy to make up the air, thereby improving the heating effect of the heat pump unit.

[0062] After the compressor is controlled to operate at the first starting frequency for a first preset time, the water inlet temperature is detected in real time. When the water inlet temperature is below the first threshold, the opening of the main electronic expansion valve is adjusted to a second opening, wherein the second opening is greater than the initial opening corresponding to the second control strategy. While adjusting the opening of the main electronic expansion valve to the second opening, the operation of the heat pump unit is controlled according to the first control strategy. As described above, when the ambient temperature is within the ultra-low temperature range and the water inlet temperature is relatively low (i.e., the water inlet is below the first threshold), in order to avoid the system low pressure being too low when the heat pump unit is turned on due to the low initial opening of the main electronic expansion valve, the system low pressure being too low when the heat pump unit is turned on will cause a low pressure fault. Therefore, the opening of the main electronic expansion valve is increased to the second opening, which can increase the system low pressure value when the heat pump unit is turned on, avoid low pressure faults, thereby improving the operating stability and reliability of the heat pump unit, and further improving the heating effect of the heat pump unit.

[0063] For example, assuming that the preset initial opening is N1, the second opening is set to N low =N1+N2, where N2 is the number of steps of the electronic expansion valve, which is a preset value. By setting a second opening higher than the initial opening at ultra-low ambient temperature, the system low pressure value when the heat pump unit is turned on can be increased to avoid low pressure failures, thereby improving the operating stability and reliability of the heat pump unit, and further improving the heating effect of the heat pump unit.

[0064] After the compressor is controlled to run at the first starting frequency for a first preset time, in addition to real-time detection of the water inlet temperature, the water outlet temperature also needs to be detected in real time, and the target water temperature is obtained. The target frequency value is determined according to the water outlet temperature and the ambient temperature. For example, a reference relationship between the water outlet temperature, the ambient temperature, and the target frequency value is preset. When the heat pump unit is subsequently controlled, the target frequency value corresponding to the water outlet temperature and the ambient temperature is searched according to the preset reference relationship to determine the target frequency value at this time.

[0065] In one embodiment, the relationship between the outlet water temperature, the ambient temperature and the target frequency value is shown in Table 1 below:

[0066]

[0067] Table 1

[0068] Therefore, the target frequency value corresponding to the outlet water temperature and the ambient temperature is found according to the preset comparison relationship (eg, Table 1).

[0069] After the outlet water temperature is detected in real time and the target water temperature is determined, the target water temperature is compared with the outlet water temperature. When the difference between the target water temperature and the outlet water temperature is below the second threshold, the compressor is controlled to perform frequency increase processing at the first frequency increase speed until the target frequency value is reached. It should be noted that the control process is performed on the basis of the first control strategy, that is, the compressor is controlled to perform frequency increase processing at the first frequency increase speed on the basis of taking the first frequency as the minimum operating frequency until the target frequency value is reached. For example, it is assumed that the second threshold is 10°C and the first frequency increase speed is 3HZ / s. When the difference between the target water temperature and the outlet water temperature is within 10°C, the compressor is controlled to perform frequency increase processing at a speed of 3HZ / s until the target frequency value is reached.

[0070] After the outlet water temperature is detected in real time and the target water temperature is determined, the target water temperature is compared with the outlet water temperature. When the difference between the target water temperature and the outlet water temperature exceeds the second threshold, the compressor is controlled to perform frequency increase processing at the second frequency increase speed until the difference between the target water temperature and the outlet water temperature is below the second threshold, and the compressor is controlled to perform frequency increase processing at the first frequency increase speed until the target frequency value is reached. It should be noted that the control process is executed on the basis of the first control strategy, that is, the compressor is controlled to perform frequency increase processing at the second frequency increase speed on the basis of taking the first frequency as the lowest operating frequency, until the difference between the target water temperature and the outlet water temperature is below the second threshold, and the compressor is controlled to perform frequency increase processing at the first frequency increase speed until the target frequency value is reached. For example, assuming that the second threshold is 10°C, the first frequency increase speed is 3HZ / s, and the second frequency increase speed is 5HZ / s. When the difference between the target water temperature and the outlet water temperature exceeds 10°C, the compressor is controlled to increase the frequency at a speed of 5HZ / s. When the difference between the target water temperature and the outlet water temperature is within 10°C, the compressor is controlled to increase the frequency at a speed of 3HZ / s until the target frequency value is reached.

[0071] As described above, the frequency increase speed of the compressor is dynamically adjusted by the difference between the outlet water temperature and the target water temperature to prevent the exhaust temperature from rising too quickly, thereby improving the operating stability and reliability of the heat pump unit.

[0072] In one embodiment, the operation of the heat pump unit is controlled according to a preset first control strategy. On the basis of taking the first frequency as the minimum operating frequency, it also includes: obtaining the current exhaust superheat, return air superheat and target water temperature and other parameters of the heat pump unit, and executing a preset PID control strategy according to the exhaust superheat, return air superheat and target water temperature to adjust the operating frequency of the compressor and the opening of the valves in the heat pump unit (including the main electronic expansion valve and the enthalpy increase electronic expansion valve), thereby improving the heating effect of the heat pump unit, and based on taking the first frequency as the minimum operating frequency at ultra-low ambient temperature, the heat pump unit can better return oil in an ultra-low temperature environment, thereby improving the operating reliability and stability of the heat pump unit.

[0073] In one embodiment, the outlet water temperature is detected in real time, and when the outlet water temperature exceeds the third threshold, the compressor is controlled to operate at the first frequency. For example, in Table 1, when the outlet water temperature exceeds 60° C., the compressor is controlled to operate at the first frequency of 55 Hz.

[0074] In one embodiment, when the heat pump unit is turned on, a start-up instruction is received, and in response to the start-up instruction, the ambient temperature is detected. When the ambient temperature is within a preset normal temperature range, the compressor is controlled to operate at a preset start-up frequency; after the compressor has been running for a second preset time, the opening of the main electronic expansion valve is adjusted to an initial opening; and the operation of the heat pump unit is controlled according to a preset second control strategy.

[0075] As mentioned above, when the ambient temperature is within the ultra-low temperature range, by regulating the operating frequency and the minimum operating frequency of the compressor, the heat pump unit can improve the operating stability and reliability while meeting the heating demand, thereby solving the problem of excessive exhaust gas of the existing (R32) refrigerant under high water temperature conditions, so that the heat pump unit can effectively maintain a suitable exhaust gas temperature under ultra-low ambient temperature and high water temperature conditions, further improving the operating stability and reliability of the heat pump unit.

[0076] As described above, under ultra-low ambient temperature, by setting the initial opening of the main electronic expansion valve at different inlet water temperatures, that is, when the inlet water temperature exceeds the first threshold, the initial opening is set to the first opening, and when the inlet water temperature is below the first threshold, the initial opening is set to the second opening, so as to solve the problems of high exhaust gas at high water temperature and low temperature failure caused by opening at low water temperature, thereby improving the operating stability and reliability of the heat pump unit during the start-up phase.

[0077] As described above, by controlling the speed of increasing and decreasing the frequency of the compressor through the difference between the target water temperature and the outlet water temperature, the target temperature value can be reached quickly, thereby improving the user experience.

[0078] As mentioned above, when the ambient temperature is within the ultra-low temperature range, the minimum operating frequency of the heat pump unit is increased to the first frequency, so as to avoid the problem of the heat pump unit being unable to return oil due to the operation of the heat pump unit at a lower minimum operating frequency in an ultra-low temperature environment. This embodiment increases the minimum operating frequency of the heat pump unit to the first frequency, so that the heat pump unit can return oil better in an ultra-low temperature environment, thereby improving the operational reliability and stability of the heat pump unit. In addition, when the ambient temperature is within the ultra-low temperature range, the opening of the main electronic expansion valve is reduced to reduce the refrigerant flow rate and avoid a large amount of the mixture of refrigerant and oil rushing out of the compressor, thereby avoiding problems caused by too low oil in the compressor, and further improving the operational reliability and stability of the heat pump unit.

[0079] Based on the above embodiments, Figure 3 This is a schematic diagram of the structure of a heat pump unit control device provided in an embodiment of the present application. Figure 3 The heat pump unit control device provided in this embodiment specifically includes: a command response module 21, a low-temperature start module 22, a first adjustment module 23 and a first control strategy execution module 24.

[0080] The instruction response module 21 is used to receive a start instruction, and detect the ambient temperature in response to the start instruction;

[0081] A low temperature starting module 22 is used to control the compressor to operate at a first starting frequency when the ambient temperature is within a preset ultra-low temperature range;

[0082] The first adjustment module 23 is used to detect the inlet water temperature in real time after the compressor runs for a first preset time, and when the inlet water temperature exceeds a first threshold, adjust the opening of the main electronic expansion valve to a first opening;

[0083] The first control strategy execution module 24 is used to control the operation of the heat pump unit according to the preset first control strategy. The first control strategy uses the first frequency as the minimum operating frequency, the first frequency is greater than the minimum operating frequency corresponding to the second control strategy, the first opening is less than the initial opening corresponding to the second control strategy, and the second control strategy is a control strategy corresponding to a preset normal temperature range, and the temperature value in the normal temperature range is higher than the temperature value in the ultra-low temperature range.

[0084] In one embodiment, the heat pump unit control device further includes: a water temperature detection module, a target frequency determination module and a first frequency increase module;

[0085] The water temperature detection module is used to detect the outlet water temperature in real time and obtain the target water temperature;

[0086] A target frequency determination module is used to determine the target frequency value according to the outlet water temperature and the ambient temperature;

[0087] The first frequency increasing module is used for controlling the compressor to perform frequency increasing processing at a first frequency increasing speed when the difference between the target water temperature and the outlet water temperature is below a second threshold value, until the target frequency value is reached.

[0088] In one embodiment, the heat pump unit control device further includes: a second frequency-upgrading module;

[0089] The second frequency up-conversion module is used to control the compressor to perform frequency up-conversion processing at a second frequency up-conversion speed when the difference between the target water temperature and the outlet water temperature exceeds a second threshold value, and control the compressor to perform frequency up-conversion processing at a first frequency up-conversion speed until the target frequency value is reached until the difference between the target water temperature and the outlet water temperature is below the second threshold value.

[0090] In one embodiment, the heat pump unit control device further includes: a second adjustment module;

[0091] The second adjustment module is used to adjust the opening of the main electronic expansion valve to a second opening when the water inlet temperature is below the first threshold, and control the operation of the heat pump unit according to the preset first control strategy, and the second opening is greater than the initial opening.

[0092] In one embodiment, the first control strategy execution module 24 includes: a parameter acquisition submodule and a strategy control submodule;

[0093] The parameter acquisition submodule is used to obtain the current exhaust gas superheat, return gas superheat and target water temperature of the heat pump unit;

[0094] The strategy control submodule is used to control the operation of the heat pump unit according to the preset first control strategy based on the exhaust gas superheat, the return gas superheat and the target water temperature, and execute the preset PID control strategy to adjust the operating frequency of the compressor and the opening of the valve in the heat pump unit, the valve including the main electronic expansion valve and the enthalpy increase electronic expansion valve.

[0095] In one embodiment, the heat pump unit control device further includes: a normal temperature start-up module, a third adjustment module, and a second control strategy execution module;

[0096] Normal temperature start module, used to control the compressor to run at a preset start frequency when the ambient temperature is within a preset normal temperature range;

[0097] A third adjustment module is used to adjust the opening of the main electronic expansion valve to the initial opening after the compressor runs for a second preset time;

[0098] The second control strategy execution module is used to control the operation of the heat pump unit according to the preset second control strategy.

[0099] In one embodiment, the heat pump unit control device further includes: a fourth adjustment module;

[0100] The fourth adjustment module is used to detect the outlet water temperature in real time, and when the outlet water temperature exceeds a third threshold, control the compressor to operate at the first frequency.

[0101] The heat pump unit control device provided in the embodiment of the present application can be used to execute the heat pump unit control method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0102] The present application embodiment provides a heat pump unit control device, referring to Figure 4 The heat pump unit control device includes: a processor 31, a memory 32, a communication module 33, an input device 34 and an output device 35. The number of processors in the heat pump unit control device can be one or more, and the number of memories in the heat pump unit control device can be one or more. The processor, memory, communication module, input device and output device of the heat pump unit control device can be connected through a bus or other methods.

[0103] The memory 32, as a computer-readable storage medium, can be used to store software programs, computer executable programs and modules, such as program instructions / modules corresponding to the heat pump unit control method of any embodiment of the present application (for example, the instruction response module, the low temperature start module, the first adjustment module and the first control strategy execution module in the heat pump unit control device). The memory may mainly include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the device, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device or other non-volatile solid-state storage device. In some instances, the memory may further include a memory remotely arranged relative to the processor, and these remote memories may be connected to the device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network and a combination thereof.

[0104] The communication module 33 is used for data transmission.

[0105] The processor 31 executes various functional applications and data processing of the device by running the software programs, instructions and modules stored in the memory, that is, realizes the above-mentioned heat pump unit control method.

[0106] The input device 34 may be used to receive input digital or character information and generate key signal input related to user settings and function control of the device. The output device 35 may include a display device such as a display screen.

[0107] The heat pump unit control device provided above can be used to execute the heat pump unit control method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0108] An embodiment of the present application also provides a storage medium storing computer executable instructions, which are used to execute a heat pump unit control method when executed by a computer processor. The heat pump unit control method includes: receiving a start instruction, responding to the start instruction, and detecting the ambient temperature; when the ambient temperature is within a preset ultra-low temperature range, controlling the compressor to operate at a first start frequency; after the compressor has been running for a first preset time, detecting the water inlet temperature in real time, and when the water inlet temperature exceeds a first threshold, adjusting the opening of the main electronic expansion valve to a first opening; controlling the operation of the heat pump unit according to a preset first control strategy, the first control strategy uses the first frequency as the minimum operating frequency, the first frequency is greater than the minimum operating frequency corresponding to the second control strategy, the first opening is less than the initial opening corresponding to the second control strategy, and the second control strategy is a control strategy corresponding to a preset normal temperature range, and the temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

[0109] Storage medium - any of various types of memory devices or storage devices. The term "storage medium" is intended to include: installation media, such as CD-ROM, floppy disk or tape device; computer system memory or random access memory, such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory, such as flash memory, magnetic media (such as hard disk or optical storage); registers or other similar types of memory elements, etc. Storage media may also include other types of memory or combinations thereof. In addition, the storage medium may be located in the first computer system in which the program is executed, or may be located in a different second computer system, which is connected to the first computer system via a network (such as the Internet). The second computer system can provide program instructions to the first computer for execution. The term "storage medium" may include two or more storage media residing in different locations (for example, in different computer systems connected by a network). The storage medium may store program instructions (for example, embodied as a computer program) that can be executed by one or more processors.

[0110] Of course, the computer executable instructions of a storage medium storing computer executable instructions provided in an embodiment of the present application are not limited to the heat pump unit control method described above, and can also execute related operations in the heat pump unit control method provided in any embodiment of the present application.

[0111] The heat pump unit control device, storage medium and heat pump unit control equipment provided in the above embodiments can execute the heat pump unit control method provided in any embodiment of the present application. For technical details not described in detail in the above embodiments, please refer to the heat pump unit control method provided in any embodiment of the present application.

[0112] The above are only preferred embodiments of the present application and the technical principles used. The present application is not limited to the specific embodiments described herein, and various obvious changes, readjustments and substitutions that can be made by those skilled in the art will not deviate from the scope of protection of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the claims.

Claims

1. A heat pump unit control method, It is characterized in that include: receiving a start instruction, and detecting an ambient temperature in response to the start instruction; When the ambient temperature is within a preset ultra-low temperature range, controlling the compressor to operate at a first starting frequency; After the compressor runs for a first preset time, the water inlet temperature is detected in real time, and when the water inlet temperature exceeds a first threshold, the opening of the main electronic expansion valve is adjusted to a first opening; The operation of the heat pump unit is controlled according to a preset first control strategy, wherein the first control strategy uses a first frequency as the minimum operating frequency, the first frequency is greater than the minimum operating frequency corresponding to the second control strategy, the first opening is less than an initial opening corresponding to the second control strategy, and the second control strategy is a control strategy corresponding to a preset normal temperature range, and the temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

2. The method according to claim 1, It is characterized in that After the compressor runs for a first preset time, the method comprises: Real-time detection of water temperature and acquisition of target water temperature; Determining a target frequency value according to the outlet water temperature and the ambient temperature; When the difference between the target water temperature and the outlet water temperature is below a second threshold, the compressor is controlled to perform frequency increase processing at a first frequency increase speed until the target frequency value is reached.

3. The method according to claim 2, It is characterized in that After determining the target frequency value according to the outlet water temperature and the ambient temperature, the method further comprises: When the difference between the target water temperature and the outlet water temperature exceeds a second threshold, the compressor is controlled to perform frequency increase processing at a second frequency increase speed until the difference between the target water temperature and the outlet water temperature is below the second threshold, and the compressor is controlled to perform frequency increase processing at a first frequency increase speed until the target frequency value is reached.

4. The method according to claim 1, It is characterized in that After the real-time detection of the inlet water temperature, the method includes: When the water inlet temperature is below the first threshold, the opening of the main electronic expansion valve is adjusted to a second opening, and the operation of the heat pump unit is controlled according to a preset first control strategy, and the second opening is greater than the initial opening.

5. The method according to claim 1, It is characterized in that The step of controlling the operation of the heat pump unit according to a preset first control strategy includes: Obtaining the current exhaust gas superheat, return gas superheat and target water temperature of the heat pump unit; According to the exhaust gas superheat, return gas superheat and target water temperature, the operation of the heat pump unit is controlled according to a preset first control strategy, and a preset PID control strategy is executed to adjust the operating frequency of the compressor and the opening of the valve in the heat pump unit, wherein the valve includes a main electronic expansion valve and an enthalpy-increasing electronic expansion valve.

6. The method according to claim 1, It is characterized in that The receiving of the start instruction, responding to the start instruction, and detecting the ambient temperature include: When the ambient temperature is within a preset normal temperature range, controlling the compressor to operate at a preset starting frequency; After the compressor runs for a second preset time, adjusting the opening of the main electronic expansion valve to the initial opening; The operation of the heat pump unit is controlled according to the preset second control strategy.

7. The method according to any one of claims 1 to 6, It is characterized in that The receiving of the start instruction, responding to the start instruction, and detecting the ambient temperature include: The outlet water temperature is detected in real time, and when the outlet water temperature exceeds a third threshold, the compressor is controlled to operate at the first frequency.

8. A heat pump unit control device, It is characterized in that include: An instruction response module, used for receiving a start instruction and detecting the ambient temperature in response to the start instruction; A low-temperature starting module, used to control the compressor to operate at a first starting frequency when the ambient temperature is within a preset ultra-low temperature range; A first adjustment module is used to detect the inlet water temperature in real time after the compressor runs for a first preset time, and when the inlet water temperature exceeds a first threshold, adjust the opening of the main electronic expansion valve to a first opening; The first control strategy execution module is used to control the operation of the heat pump unit according to a preset first control strategy, wherein the first control strategy uses a first frequency as the minimum operating frequency, the first frequency is greater than the minimum operating frequency corresponding to the second control strategy, the first opening is less than the initial opening corresponding to the second control strategy, and the second control strategy is a control strategy corresponding to a preset normal temperature range, and the temperature value within the normal temperature range is higher than the temperature value within the ultra-low temperature range.

9. A heat pump unit control device, It is characterized in that include: memory and one or more processors; The memory is used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of claims 1 to 7.

10. A storage medium storing computer executable instructions, It is characterized in that The computer executable instructions are used to perform the method according to any one of claims 1 to 7 when executed by a processor.

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