Heat pump injection enthalpy increasing control method and device, storage medium and heat pump unit

Abstract

The invention discloses a heat pump injection enthalpy increasing control method and device, a storage medium and a heat pump unit, and is applied to the heat pump unit, the target exhaust superheat degree in the heat pump unit is determined, the exhaust superheat degree in the heat pump unit is determined, and the exhaust superheat degree and the target exhaust superheat degree are compared to obtain a comparison result; and the injection state of the heat pump unit is detected, and the opening degree of an injection valve in the heat pump unit is controlled based on the comparison result and the injection state. Therefore, according to the comparison result of the exhaust superheat degree and the target superheat degree and the injection state, the opening degree of the injection valve can be dynamically adjusted, the refrigerant injection state is accurately controlled, it is ensured that the exhaust temperature is maintained within the target range, and meanwhile the heating efficiency and operation reliability of the system are improved; and the requirement for efficient heating in a high outlet water temperature mode is met.

Description

Technical Field

[0001] The present application relates to the technical field of heat pumps, and in particular to a heat pump injection enthalpy increase control method, device, storage medium and heat pump unit. Background Art

[0002] As an efficient and environmentally friendly energy conversion device, heat pump units are widely used in heating, cooling and hot water supply. In order to improve the heating efficiency of heat pump units, injection enthalpy increase technology is widely used in heat pump units. By injecting an appropriate amount of refrigerant into the middle cavity of the compressor, the compression process is adjusted to improve the overall performance of the system.

[0003] However, when the heat pump unit is in the high outlet water temperature operation mode, that is, when the temperature difference between the inlet and outlet water of the system is large, the control of refrigerant injection becomes particularly complicated. On the one hand, injecting too much gaseous refrigerant will cause the compressor exhaust temperature to increase, which not only increases the energy consumption of the compressor, but may also trigger overheating protection and reduce the operating reliability of the unit. On the other hand, injecting too much liquid refrigerant will cause the exhaust temperature to be low, affecting the heating capacity of the system. Furthermore, most of the injection enthalpy increase control methods in related technologies are based on a preset injection amount or a fixed injection ratio for adjustment, lacking the ability to dynamically adjust according to the real-time operating conditions of the system, and it is difficult to accurately match the refrigerant demand in the high outlet water temperature mode.

[0004] Therefore, how to achieve precise control of the refrigerant injection state in the high water outlet temperature mode to optimize system performance has become an urgent problem to be solved in the current field of heat pump technology. Summary of the invention

[0005] The embodiments of the present application provide a heat pump injection enthalpy increase control method, device, storage medium and heat pump unit, which can dynamically adjust the opening of the injection valve and accurately control the state of the injected refrigerant to ensure that the exhaust temperature is maintained within the target range, while improving the heating efficiency and operational reliability of the system to meet the high-efficiency heating requirements under the high water outlet temperature mode.

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

[0007] Determining a target exhaust gas superheat in the heat pump unit, and determining an exhaust gas superheat in the heat pump unit;

[0008] Comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result;

[0009] Detecting the injection state of the heat pump unit;

[0010] The opening degree of the injection valve in the heat pump unit is controlled based on the comparison result and the injection state.

[0011] In one embodiment, the above-mentioned determination of the target exhaust gas superheat in the above-mentioned heat pump unit includes:

[0012] Obtaining a first calculation formula for calculating a target exhaust superheat in the heat pump unit, and determining a calculated value of the target exhaust superheat according to the first calculation formula;

[0013] Determine a target exhaust superheat value range of the target exhaust superheat;

[0014] Determine the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range;

[0015] Among them, the first calculation formula is:

[0016] DSHS=Pc / Pe*X

[0017] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0018] In one embodiment, the above target exhaust superheat value range is:

[0019] DSHS min≤DSHS≤Tp_target-Tc

[0020] Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

[0021] In one embodiment, determining the calculated value of the target exhaust superheat according to the first calculation formula includes:

[0022] Detecting the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator;

[0023] Obtaining a second calculation formula for calculating the target water temperature difference in the heat pump unit, determining the target water temperature difference of the heat pump unit according to the second calculation formula, and determining a correction coefficient corresponding to the target water temperature difference according to a first mapping relationship among the target water temperature difference, the reference target water temperature difference and the reference correction coefficient;

[0024] Calculating the calculated value of the target exhaust superheat based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula;

[0025] Among them, the second calculation formula is:

[0026] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0027] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, the above A is the temperature adjustment coefficient, and the above B is the temperature comparison coefficient. The above temperature adjustment coefficient and the above temperature comparison coefficient are determined based on the above heat pump inlet water temperature.

[0028] In one embodiment, the target exhaust superheat value range for determining the target exhaust superheat includes:

[0029] Obtaining a heat pump set water temperature of the heat pump unit, and determining a target exhaust temperature corresponding to the heat pump set water temperature according to the heat pump set water temperature and referring to a second mapping relationship between the heat pump set water temperature and a reference target exhaust temperature;

[0030] Calculating the condensing temperature of the heat pump unit according to the condensing pressure;

[0031] Determining a preset maximum value for the target exhaust gas superheat according to the target exhaust gas temperature and the condensing temperature;

[0032] Obtaining a preset minimum value of the heat pump unit set for the target exhaust gas superheat;

[0033] The target exhaust superheat value range is determined according to the preset maximum value and the preset minimum value.

[0034] In one embodiment, the method of determining the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range includes:

[0035] If the above calculated value belongs to the above target exhaust superheat value range, then the target exhaust superheat in the above heat pump unit is the above calculated value;

[0036] If the calculated value is less than the preset minimum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset minimum value;

[0037] If the calculated value is greater than the preset maximum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset maximum value.

[0038] In one embodiment, the injection state includes a liquid injection state and an air injection state, and the detection of the injection state of the heat pump unit includes:

[0039] Detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature;

[0040] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state;

[0041] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the injection state.

[0042] In one embodiment, the determining of the exhaust superheat in the heat pump unit includes: detecting the exhaust temperature of the heat pump unit, obtaining the difference between the exhaust temperature and the condensing temperature, and using the difference as the exhaust superheat.

[0043] In one embodiment, the injection state includes a liquid injection state and an air injection state, and the control of the opening of the injection valve in the heat pump unit according to the comparison result and the injection state includes:

[0044] Based on the comparison result, determining whether the exhaust gas superheat is less than the target exhaust gas superheat;

[0045] If the exhaust gas superheat is less than the target exhaust gas superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or,

[0046] If the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is the injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

[0047] In a second aspect, the present application also provides a heat pump injection enthalpy increase control device, comprising:

[0048] A determination module, used to determine a target exhaust gas superheat in the heat pump unit, and to determine the exhaust gas superheat in the heat pump unit;

[0049] A comparison module, used for comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result;

[0050] A detection module, used to detect the injection status of the heat pump unit;

[0051] A control module is used to control the opening of the injection valve in the heat pump unit based on the comparison result and the injection state.

[0052] In one embodiment, the determining module is used to:

[0053] Obtaining a first calculation formula for calculating a target exhaust superheat in the heat pump unit, and determining a calculated value of the target exhaust superheat according to the first calculation formula;

[0054] Determine a target exhaust superheat value range of the target exhaust superheat;

[0055] Determine the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range;

[0056] Among them, the first calculation formula is:

[0057] DSHS=Pc / Pe*X

[0058] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0059] In one embodiment, the above target exhaust superheat value range is:

[0060] DSHS min≤DSHS≤Tp_target-Tc

[0061] Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

[0062] In one embodiment, the determining module is used to:

[0063] Detecting the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator;

[0064] Obtaining a second calculation formula for calculating the target water temperature difference in the heat pump unit, determining the target water temperature difference of the heat pump unit according to the second calculation formula, and determining a correction coefficient corresponding to the target water temperature difference according to a first mapping relationship among the target water temperature difference, the reference target water temperature difference and the reference correction coefficient;

[0065] Calculating the calculated value of the target exhaust superheat based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula;

[0066] Among them, the second calculation formula is:

[0067] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0068] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, the above A is the temperature adjustment coefficient, and the above B is the temperature comparison coefficient. The above temperature adjustment coefficient and the above temperature comparison coefficient are determined based on the above heat pump inlet water temperature.

[0069] In one embodiment, the determining module is used to:

[0070] Obtaining a heat pump set water temperature of the heat pump unit, and determining a target exhaust temperature corresponding to the heat pump set water temperature according to the heat pump set water temperature and referring to a second mapping relationship between the heat pump set water temperature and a reference target exhaust temperature;

[0071] Calculating the condensing temperature of the heat pump unit according to the condensing pressure;

[0072] Determining a preset maximum value for the target exhaust gas superheat according to the target exhaust gas temperature and the condensing temperature;

[0073] Obtaining a preset minimum value of the heat pump unit set for the target exhaust gas superheat;

[0074] The target exhaust superheat value range is determined according to the preset maximum value and the preset minimum value.

[0075] In one embodiment, the determining module is used to:

[0076] If the above calculated value belongs to the above target exhaust superheat value range, then the target exhaust superheat in the above heat pump unit is the above calculated value;

[0077] If the calculated value is less than the preset minimum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset minimum value;

[0078] If the calculated value is greater than the preset maximum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset maximum value.

[0079] In one embodiment, the detection module is used to:

[0080] Detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature;

[0081] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state;

[0082] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the injection state.

[0083] In one embodiment, the determining module is used to:

[0084] Detecting the exhaust temperature of the heat pump unit, obtaining the difference between the exhaust temperature and the condensing temperature, and using the difference as the exhaust superheat;

[0085] The injection state includes a liquid injection state and an air injection state. The control of the opening of the injection valve in the heat pump unit according to the comparison result and the injection state includes:

[0086] Based on the comparison result, determining whether the exhaust gas superheat is less than the target exhaust gas superheat;

[0087] If the exhaust gas superheat is less than the target exhaust gas superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or,

[0088] If the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is the injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

[0089] In a third aspect, an embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon. When the computer program runs on a computer, the computer executes a heat pump injection enthalpy increase control method as provided in any embodiment of the present application.

[0090] In a fourth aspect, an embodiment of the present application further provides a heat pump unit, comprising a processor and a memory, wherein the memory has a computer program, and the processor is used to execute a heat pump injection enthalpy increase control method as provided in any embodiment of the present application by calling the computer program.

[0091] The technical solution provided in the embodiment of the present application is applied to a heat pump unit, by determining the target exhaust superheat in the heat pump unit, determining the exhaust superheat in the heat pump unit, comparing the exhaust superheat with the target exhaust superheat to obtain a comparison result, and detecting the injection state of the heat pump unit, and controlling the opening of the injection valve in the heat pump unit based on the comparison result and the injection state. In this way, the present application can dynamically adjust the opening of the injection valve according to the comparison result and the injection state of the exhaust superheat and the target superheat, and accurately control the state of the injected refrigerant to ensure that the exhaust temperature is maintained within the target range, while improving the heating efficiency and operational reliability of the system, and meeting the high-efficiency heating requirements in the high outlet water temperature mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0093] Figure 1 A schematic structural diagram of a heat pump unit according to a heat pump injection enthalpy increase control method provided in an embodiment of the present application.

[0094] Figure 2 A first flow chart of a heat pump injection enthalpy increase control method provided in an embodiment of the present application.

[0095] Figure 3 A second flow chart of the heat pump injection enthalpy increase control method provided in an embodiment of the present application.

[0096] Figure 4 A schematic diagram of the structure of a heat pump injection enthalpy increase control device provided in an embodiment of the present application.

[0097] Figure 5 A first structural schematic diagram of a heat pump unit provided in an embodiment of the present application.

[0098] Figure 6 A second structural schematic diagram of the heat pump unit provided in an embodiment of the present application. DETAILED DESCRIPTION

[0099] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0100] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0101] An embodiment of the present application provides a heat pump jet enthalpy increase control method, and the executor of the heat pump jet enthalpy increase control method can be the heat pump jet enthalpy increase control device provided in the embodiment of the present application, or a heat pump unit integrating the heat pump jet enthalpy increase control device, wherein the heat pump jet enthalpy increase control device can be implemented in hardware or software.

[0102] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a heat pump unit for controlling the heat pump injection enthalpy increase provided in the embodiment of the present application. EXV refers to an electronic expansion valve, also known as an injection valve. Cooling represents refrigeration, and heating represents heating. Figure 1 The small black squares represent sensors such as temperature sensors, pressure sensors, etc. For example, different temperature data can be detected according to the different settings of the temperature sensor, such as water temperature, ambient temperature, refrigerant temperature, etc. For another example, different pressure data can be detected according to the different settings of the pressure sensor, such as condensing pressure, evaporation pressure, etc.

[0103] Next, see Figure 2 , Figure 2 The first flow chart of the heat pump injection enthalpy increase control method provided in the embodiment of the present application is shown in FIG. The heat pump injection enthalpy increase control method provided in the embodiment of the present application is applied to a heat pump unit, and the specific flow of the method can be as follows:

[0104] S110, determining a target exhaust gas superheat in the heat pump unit, and determining the exhaust gas superheat in the heat pump unit.

[0105] The target exhaust superheat is the exhaust superheat value that is preset or expected to be achieved by the heat pump unit under specific operating conditions.

[0106] In this embodiment, the target exhaust gas superheat is determined according to the current operating condition of the heat pump unit, and can be specifically calculated according to the following formula:

[0107] DSHS=Pc / Pe*X

[0108] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0109] Furthermore, a pressure sensor can be used to measure the condensing pressure Pc and the evaporating pressure Pe in the heat pump unit. In addition, the first mapping relationship between the reference target water temperature difference and the reference correction coefficient can be used to determine the correction coefficient X from the first mapping relationship based on the target water temperature difference of the heat pump unit. It should be noted that the first mapping relationship is obtained by debugging by those skilled in the art in the actual working scenario of the heat pump unit.

[0110] Specifically, when determining the target water temperature difference of the heat pump unit, it can be calculated according to the following calculation formula:

[0111] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0112] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, A is the temperature adjustment coefficient, and B is the temperature comparison coefficient. The temperature adjustment coefficient and the temperature comparison coefficient are determined based on the inlet water temperature of the heat pump.

[0113] Among them, the heat pump set water temperature refers to the set heat pump outlet water temperature, and the heat pump set water temperature can be set by the user on the online controller. The heat pump target shutdown temperature refers to the temperature value at which the heat pump system automatically stops working after reaching the preset outlet water temperature or indoor temperature. This temperature value is set to avoid overheating, energy waste and protect equipment. The temperature adjustment coefficient A and the heat pump inlet water temperature Tw_in have a third mapping relationship. Specifically, each temperature range of the heat pump inlet water temperature corresponds to a temperature adjustment coefficient. The third mapping relationship is obtained by debugging by those skilled in the art in the art in the actual working scenario of the heat pump unit. The temperature comparison coefficient B and the heat pump inlet water temperature Tw_in have a fourth mapping relationship. Specifically, each temperature range of the heat pump inlet water temperature corresponds to a temperature comparison coefficient. The fourth mapping relationship is also obtained by debugging by those skilled in the art in the art in the actual working scenario of the heat pump unit.

[0114] Among them, exhaust superheat refers to the temperature difference between the temperature of the high-temperature and high-pressure gas discharged by the compressor and the temperature at the condenser inlet (or the corresponding saturation temperature) when the high-temperature and high-pressure gas is condensed into liquid in the condenser during the operation of the heat pump unit.

[0115] In this embodiment, when determining the exhaust gas superheat in the heat pump unit, the exhaust gas superheat can be calculated according to the following formula:

[0116] DSH=Tp-Tc

[0117] Where DSH is the exhaust superheat, Tp is the exhaust temperature, and Tc is the condensing temperature.

[0118] That is, when determining the exhaust superheat in the heat pump unit, the exhaust temperature of the heat pump unit is detected, the difference between the exhaust temperature and the condensing temperature is obtained, and the difference is used as the exhaust superheat. Specifically, the exhaust temperature Tp can be measured by a temperature sensor, and the condensing temperature Tc can be calculated based on the functional relationship between the condensing temperature Tc and the condensing pressure Pc. After the condensing pressure Pc is detected, the condensing temperature Tc is solved based on Tc=f(Pc). Please refer to the relevant technology for the functional relationship Tc=f(Pc), which will not be repeated here.

[0119] S120: Compare the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result.

[0120] In this embodiment, the exhaust superheat is compared with the target exhaust superheat to obtain a comparison result, that is, the exhaust superheat and the target exhaust superheat are compared. The comparison result can be three situations: the exhaust superheat is less than the target exhaust superheat, the exhaust superheat is equal to the target exhaust superheat, and the exhaust superheat is greater than the target exhaust superheat.

[0121] S130, detecting the injection status of the heat pump unit.

[0122] In the present application, the injection state includes a liquid injection state and an air injection state. When detecting the injection state of the heat pump unit, the injection inlet temperature and the injection outlet temperature of the heat pump unit can be detected, as well as the exhaust temperature. If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature meets the preset temperature range, and the exhaust temperature at the current moment is less than the exhaust temperature at the previous moment, then the current injection state is a liquid injection state. If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not meet the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, then the current injection state is an air injection state.

[0123] The exhaust temperature refers to the temperature of the hot gas discharged from the compressor after the refrigerant in the heat pump unit is compressed, also known as the compressor exhaust temperature. The preset temperature range is obtained by technicians in this field in the actual working scenario of the heat pump unit.

[0124] Specifically, please refer to Figure 1 The jet inlet is Tjet_out, and the jet outlet is Tjet_in. Temperature sensors can be set at these two locations in the heat pump unit to detect the jet inlet temperature and jet outlet temperature. Please also refer to Figure 1, a temperature sensor can be set at the Tp position to detect the exhaust temperature. When detecting the exhaust temperature, the exhaust temperature can be detected once at a preset time interval, and the current moment is separated from the previous moment by the preset time interval. For example, the exhaust temperature Tp(n) is detected at the current moment, and the exhaust temperature Tp(n-1) is detected at the previous moment, where n is a positive integer greater than 1. If the exhaust temperature at the current moment is less than the exhaust temperature at the previous moment, Tp(n)-Tp(n-1)<0.

[0125] S140: Control the opening of the injection valve in the heat pump unit based on the comparison result and the injection state.

[0126] In this embodiment, the opening of the injection valve is adjusted based on the comparison result between the exhaust superheat and the target exhaust superheat and the injection state of the heat pump unit. Specifically, based on the comparison result, it is determined whether the exhaust superheat is less than the target exhaust superheat. If the exhaust superheat is less than the target exhaust superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or, if the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is a jet state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

[0127] In specific implementation, the present application is not limited by the execution order of the various steps described. If no conflict occurs, some steps can be performed in other orders or simultaneously.

[0128] As can be seen from the above, the heat pump injection enthalpy increase control method provided in the embodiment of the present application is applied to a heat pump unit, by determining the target exhaust superheat in the heat pump unit, determining the exhaust superheat in the heat pump unit, comparing the exhaust superheat with the target exhaust superheat to obtain a comparison result, and detecting the injection state of the heat pump unit, and controlling the opening of the injection valve in the heat pump unit based on the comparison result and the injection state. In this way, the present application can dynamically adjust the opening of the injection valve according to the comparison result and the injection state of the exhaust superheat and the target superheat, and accurately control the state of the injected refrigerant to ensure that the exhaust temperature is maintained within the target range, while improving the heating efficiency and operational reliability of the system, and meeting the high-efficiency heating requirements in the high outlet water temperature mode.

[0129] The method described in the above embodiments is further described in detail below with examples.

[0130] See also Figure 3 , Figure 3 The second flow diagram of the heat pump injection enthalpy increase control method provided in the embodiment of the present application is shown in FIG. The heat pump injection enthalpy increase control method provided in the embodiment of the present application is applied to a heat pump unit, and the method includes:

[0131] S210, determining a target exhaust gas superheat in the heat pump unit, and determining the exhaust gas superheat in the heat pump unit.

[0132] In one embodiment, the step S210 of “determining the target exhaust gas superheat in the heat pump unit” may include the following steps S2101 to S2103:

[0133] S2101, obtaining a first calculation formula for calculating a target exhaust superheat in a heat pump unit, and determining a calculated value of the target exhaust superheat according to the first calculation formula;

[0134] Among them, the first calculation formula is:

[0135] DSHS=Pc / Pe*X

[0136] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0137] Specifically, when determining the calculated value of the target exhaust superheat according to the first calculation formula, the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator can be detected to obtain a second calculation formula for calculating the target water temperature difference in the heat pump unit. The target water temperature difference of the heat pump unit is determined according to the second calculation formula. According to a first mapping relationship between the target water temperature difference, the reference target water temperature difference and the reference correction coefficient, the correction coefficient corresponding to the target water temperature difference is determined. The calculated value of the target exhaust superheat is calculated based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula.

[0138] Among them, the second calculation formula is:

[0139] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0140] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, A is the temperature adjustment coefficient, and B is the temperature comparison coefficient. The temperature adjustment coefficient and the temperature comparison coefficient are determined based on the inlet water temperature of the heat pump.

[0141] Among them, the heat pump set water temperature refers to the set heat pump outlet water temperature, and the heat pump set water temperature can be set by the user on the online controller. The heat pump target shutdown temperature refers to the temperature value at which the heat pump system automatically stops working after reaching the preset outlet water temperature or indoor temperature. This temperature value is set to avoid overheating, energy waste and protect equipment. The temperature adjustment coefficient A and the heat pump inlet water temperature Tw_in have a third mapping relationship. Specifically, each temperature range of the heat pump inlet water temperature corresponds to a temperature adjustment coefficient. The third mapping relationship is obtained by debugging by those skilled in the art in the art in the actual working scenario of the heat pump unit. The temperature comparison coefficient B and the heat pump inlet water temperature Tw_in have a fourth mapping relationship. Specifically, each temperature range of the heat pump inlet water temperature corresponds to a temperature comparison coefficient. The fourth mapping relationship is also obtained by debugging by those skilled in the art in the art in the actual working scenario of the heat pump unit.

[0142] Specifically, a pressure sensor can be used to measure the condensing pressure Pc and the evaporating pressure Pe in the heat pump unit. In addition, since there is a first mapping relationship between the reference target water temperature difference and the reference correction coefficient, the correction coefficient X can be determined from the first mapping relationship based on the target water temperature difference of the heat pump unit obtained by the second calculation formula. It should be noted that the first mapping relationship is obtained by debugging by those skilled in the art in the actual working scenario of the heat pump unit.

[0143] S2102, determining a target exhaust gas superheat value range of a target exhaust gas superheat;

[0144] The target exhaust superheat value range can be determined by the following inequality:

[0145] DSHS min≤DSHS≤Tp_target-Tc

[0146] Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

[0147] The preset minimum value is a lower limit set for the performance of the heat pump unit itself, and is set by technicians in this field after performing performance debugging on the heat pump unit.

[0148] Among them, Tp_target is the target exhaust temperature, which is an expected exhaust temperature value determined when the heat pump system is designed. It reflects the state of the refrigerant after being compressed in the compressor. The target exhaust temperature is positively correlated with the heat pump set temperature. The higher the heat pump set temperature, the higher the target exhaust temperature. There is a second mapping relationship between the reference heat pump set water temperature and the reference target exhaust temperature. The second mapping relationship is obtained by debugging by those skilled in the art in the actual working scenario of the heat pump unit. After determining the current heat pump set temperature, the corresponding target exhaust temperature can be determined according to the second mapping relationship.

[0149] Among them, the condensation temperature Tc can be calculated according to the functional relationship between the condensation temperature Tc and the condensation pressure Pc. After the condensation pressure Pc is detected, the condensation temperature Tc is solved based on Tc=f(Pc). Please refer to the relevant technology for the functional relationship Tc=f(Pc), which will not be repeated here.

[0150] Furthermore, when determining the target exhaust superheat value range of the target exhaust superheat, the heat pump set water temperature of the heat pump unit can be obtained, and the target exhaust temperature corresponding to the heat pump set water temperature can be determined based on the heat pump set water temperature and with reference to a second mapping relationship between the heat pump set water temperature and the reference target exhaust temperature. The condensing temperature of the heat pump unit is calculated based on the condensing pressure, and a preset maximum value for the target exhaust superheat is determined based on the target exhaust temperature and the condensing temperature. The preset minimum value set for the target exhaust superheat of the heat pump unit is obtained, and the target exhaust superheat value range is determined based on the preset maximum value and the preset minimum value.

[0151] It can be understood that the preset minimum value is the above-mentioned DSHS min, and the preset maximum value is Tp_target-Tc.

[0152] S2103, determining a target exhaust gas superheat in the heat pump unit based on the calculated value and a target exhaust gas superheat value range;

[0153] Specifically, when determining the target exhaust superheat in the heat pump unit based on the calculated value and the target exhaust superheat value range, if the calculated value belongs to the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the calculated value; if the calculated value is less than the preset minimum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset minimum value; if the calculated value is greater than the preset maximum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset maximum value.

[0154] In one embodiment, when determining the exhaust gas superheat in the heat pump unit, the exhaust gas superheat can be calculated according to the following formula:

[0155] DSH=Tp-Tc

[0156] Where DSH is the exhaust superheat, Tp is the exhaust temperature, and Tc is the condensing temperature.

[0157] That is, when determining the exhaust superheat in the heat pump unit, the exhaust temperature of the heat pump unit is detected, the difference between the exhaust temperature and the condensing temperature is obtained, and the difference is used as the exhaust superheat. Specifically, the exhaust temperature Tp can be measured by a temperature sensor, and the condensing temperature Tc can be calculated based on the functional relationship between the condensing temperature Tc and the condensing pressure Pc. After the condensing pressure Pc is detected, the condensing temperature Tc is solved based on Tc=f(Pc). Please refer to the relevant technology for the functional relationship Tc=f(Pc), which will not be repeated here.

[0158] S220: Compare the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result.

[0159] In this embodiment, the exhaust superheat is compared with the target exhaust superheat to obtain a comparison result, that is, the exhaust superheat and the target exhaust superheat are compared. The comparison result can be three situations: the exhaust superheat is less than the target exhaust superheat, the exhaust superheat is equal to the target exhaust superheat, and the exhaust superheat is greater than the target exhaust superheat.

[0160] S230, detecting the injection status of the heat pump unit.

[0161] In one embodiment, the injection state includes a liquid injection state and an air injection state, and step S230 "detecting the injection state of the heat pump unit" may include the following steps S2301-S2303:

[0162] S2301, detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature;

[0163] S2302: If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state;

[0164] S2303: If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the injection state.

[0165] The exhaust temperature refers to the temperature of the hot gas discharged from the compressor after the refrigerant in the heat pump unit is compressed, also known as the compressor exhaust temperature. The preset temperature range is obtained by technicians in this field in the actual working scenario of the heat pump unit.

[0166] Specifically, please refer to Figure 1The jet inlet is Tjet_out, and the jet outlet is Tjet_in. Temperature sensors can be set at these two locations in the heat pump unit to detect the jet inlet temperature and jet outlet temperature. Please also refer to Figure 1 , a temperature sensor can be set at the Tp position to detect the exhaust temperature. When detecting the exhaust temperature, the exhaust temperature can be detected once at a preset time interval, and the current moment is separated from the previous moment by the preset time interval. For example, the exhaust temperature Tp(n) is detected at the current moment, and the exhaust temperature Tp(n-1) is detected at the previous moment, where n is a positive integer greater than 1. If the exhaust temperature at the current moment is less than the exhaust temperature at the previous moment, Tp(n)-Tp(n-1)<0.

[0167] S240. Based on the comparison result, determine whether the exhaust superheat is less than the target exhaust superheat; if the exhaust superheat is less than the target exhaust superheat, go to step 250; if the exhaust superheat is greater than or equal to the target exhaust superheat, go to step 260.

[0168] S250, determine whether the injection state of the heat pump unit is the liquid injection state; if so, go to step S270, if not, go to step S280.

[0169] S260, determine whether the injection state of the heat pump unit is the injection state; if so, go to step S270, if not, go to step S280.

[0170] S270: Reduce the opening of the injection valve.

[0171] S280: Increase the opening of the injection valve.

[0172] As can be seen from the above, the heat pump injection enthalpy increase control method proposed in the embodiment of the present application determines the target exhaust superheat in the heat pump unit, and determines the exhaust superheat in the heat pump unit, compares the exhaust superheat with the target exhaust superheat to obtain a comparison result, and detects the injection state of the heat pump unit. If the exhaust superheat is less than the target exhaust superheat, and the injection state of the heat pump unit is a liquid injection state, the opening of the injection valve is reduced; if the exhaust superheat is less than the target exhaust superheat, and the injection state of the heat pump unit is a non-liquid injection state, the opening of the injection valve is increased; if the exhaust superheat is greater than or equal to the target exhaust superheat, and the injection state of the heat pump unit is a jet state, the opening of the injection valve is reduced; if the exhaust superheat is greater than or equal to the target exhaust superheat, and the injection state of the heat pump unit is a jet state, the opening of the injection valve is reduced; if the exhaust superheat is greater than or equal to the target exhaust superheat, and the injection state of the heat pump unit is a non-jet state, the opening of the injection valve is increased. Therefore, the present application can dynamically adjust the opening of the injection valve according to the comparison results of the exhaust superheat and the target superheat and the injection status, and accurately control the state of the injected refrigerant to ensure that the exhaust temperature is maintained within the target range, while improving the heating efficiency and operational reliability of the system to meet the high-efficiency heating requirements under the high water outlet temperature mode.

[0173] In one embodiment, a heat pump injection enthalpy increase control device is also provided. Figure 4 , Figure 4 The schematic diagram of the structure of the heat pump jet enthalpy increase control device 300 provided in the embodiment of the present application. The heat pump jet enthalpy increase control device 300 is applied to a heat pump unit, and the heat pump jet enthalpy increase control device 300 includes a determination module 301, a comparison module 302, a detection module 303 and a control module 304, as follows:

[0174] The determination module 301 is used to determine the target exhaust gas superheat in the heat pump unit and determine the exhaust gas superheat in the heat pump unit;

[0175] A comparison module 302 is used to compare the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result;

[0176] A detection module 303 is used to detect the injection state of the heat pump unit;

[0177] The control module 304 is used to control the opening of the injection valve in the heat pump unit based on the comparison result and the injection state.

[0178] In one embodiment, the determination module 301 is used to: obtain a first calculation formula for calculating the target exhaust superheat in the heat pump unit, and determine a calculated value of the target exhaust superheat according to the first calculation formula;

[0179] Determine a target exhaust superheat value range of the target exhaust superheat;

[0180] Determine the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range;

[0181] Among them, the first calculation formula is:

[0182] DSHS=Pc / Pe*X

[0183] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0184] In one embodiment, the above target exhaust superheat value range is:

[0185] DSHS min≤DSHS≤Tp_target-Tc

[0186] Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

[0187] In one implementation, the determination module 301 is configured to:

[0188] Detecting the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator;

[0189] Obtaining a second calculation formula for calculating the target water temperature difference in the heat pump unit, determining the target water temperature difference of the heat pump unit according to the second calculation formula, and determining a correction coefficient corresponding to the target water temperature difference according to a first mapping relationship among the target water temperature difference, the reference target water temperature difference and the reference correction coefficient;

[0190] Calculating the calculated value of the target exhaust superheat based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula;

[0191] Among them, the second calculation formula is:

[0192] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0193] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, the above A is the temperature adjustment coefficient, and the above B is the temperature comparison coefficient. The above temperature adjustment coefficient and the above temperature comparison coefficient are determined based on the above heat pump inlet water temperature.

[0194] In one implementation, the determination module 301 is configured to:

[0195] Obtaining a heat pump set water temperature of the heat pump unit, and determining a target exhaust temperature corresponding to the heat pump set water temperature according to the heat pump set water temperature and referring to a second mapping relationship between the heat pump set water temperature and a reference target exhaust temperature;

[0196] Calculating the condensing temperature of the heat pump unit according to the condensing pressure;

[0197] Determining a preset maximum value for the target exhaust gas superheat according to the target exhaust gas temperature and the condensing temperature;

[0198] Obtaining a preset minimum value of the heat pump unit set for the target exhaust gas superheat;

[0199] The target exhaust superheat value range is determined according to the preset maximum value and the preset minimum value.

[0200] In one implementation, the determination module 301 is configured to:

[0201] If the above calculated value belongs to the above target exhaust superheat value range, then the target exhaust superheat in the above heat pump unit is the above calculated value;

[0202] If the calculated value is less than the preset minimum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset minimum value;

[0203] If the calculated value is greater than the preset maximum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset maximum value.

[0204] In one implementation, the detection module 303 is used to:

[0205] Detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature;

[0206] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state;

[0207] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the injection state.

[0208] In one implementation, the determination module 301 is configured to:

[0209] Detecting the exhaust temperature of the heat pump unit, obtaining the difference between the exhaust temperature and the condensing temperature, and using the difference as the exhaust superheat;

[0210] The injection state includes a liquid injection state and an air injection state. The control of the opening of the injection valve in the heat pump unit according to the comparison result and the injection state includes:

[0211] Based on the comparison result, determining whether the exhaust gas superheat is less than the target exhaust gas superheat;

[0212] If the exhaust gas superheat is less than the target exhaust gas superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or,

[0213] If the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is the injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

[0214] It should be noted that the heat pump jet enthalpy increase control device provided in the embodiment of the present application and the heat pump jet enthalpy increase control method in the above embodiment belong to the same concept. Any method provided in the heat pump jet enthalpy increase control method embodiment can be implemented through the heat pump jet enthalpy increase control device. The specific implementation process is detailed in the heat pump jet enthalpy increase control method embodiment, which will not be repeated here.

[0215] In addition, in order to better implement the heat pump injection enthalpy increase control method in the embodiment of the present application, based on the heat pump injection enthalpy increase control method, the present application also provides a heat pump unit. Figure 5 , Figure 5 The first structural diagram of the heat pump unit provided in the embodiment of the present application. The heat pump unit 400 includes a processor 401 and a memory 402. The processor 401 is electrically connected to the memory 402.

[0216] The processor 401 is the control center of the heat pump unit 400. It uses various interfaces and lines to connect various parts of the entire heat pump unit. By running or calling the computer program stored in the memory 402, and calling the data stored in the memory 402, it executes various functions of the heat pump unit and processes data, thereby monitoring the heat pump unit as a whole. Among them, the processor 401 can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0217] The memory 402 can be used to store computer programs and data. The computer program stored in the memory 402 contains instructions that can be executed in the processor. The computer program can form various functional modules. The processor 401 executes various functional applications and data processing by calling the computer program stored in the memory 402. Among them, the memory 402 can mainly include a program storage area and a data storage area. The program storage area can store an operating system, an application required for at least one function (such as a sound playback function, an image playback function, etc.), etc.; the data storage area can store data created according to the use of the heat pump unit 400 (such as audio data, video data, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0218] In this embodiment, the processor 401 in the heat pump unit 400 will load instructions corresponding to the processes of one or more computer programs into the memory 402 according to the following steps, and the processor 401 will run the computer program stored in the memory 402 to achieve various functions:

[0219] Determining a target exhaust gas superheat in the heat pump unit, and determining an exhaust gas superheat in the heat pump unit;

[0220] Comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result;

[0221] Detecting the injection state of the heat pump unit;

[0222] The opening degree of the injection valve in the heat pump unit is controlled based on the comparison result and the injection state.

[0223] In one embodiment, see Figure 6 , Figure 6 A second structural diagram of a heat pump unit provided in an embodiment of the present application. The heat pump unit 400 further includes: a radio frequency circuit 403, a display screen 404, a control circuit 405, an input unit 406, an audio circuit 407, a sensor 408, and a power supply 409. The processor 401 is electrically connected to the radio frequency circuit 403, the display screen 404, the control circuit 405, the input unit 406, the audio circuit 407, the sensor 408, and the power supply 409, respectively.

[0224] The radio frequency circuit 403 is used to send and receive radio frequency signals to communicate with network equipment or other heat pump units through wireless communication.

[0225] The display screen 404 may be used to display information input by a user or information provided to a user and various graphical user interfaces of the heat pump unit. These graphical user interfaces may be composed of images, texts, icons, videos and any combination thereof.

[0226] The control circuit 405 is electrically connected to the display screen 404 and is used to control the display screen 404 to display information.

[0227] The input unit 406 can be used to receive input numbers, character information or user feature information (such as fingerprints), and generate keyboard, mouse, joystick, optical or trackball signal input related to user settings and function control. The input unit 406 can include a fingerprint recognition module.

[0228] The audio circuit 407 can provide an audio interface between the user and the heat pump unit through a speaker and a microphone. The audio circuit 407 includes a microphone. The microphone is electrically connected to the processor 401. The microphone is used to receive voice information input by the user.

[0229] The sensor 408 is used to collect external environment information. The sensor 408 may include one or more sensors such as an environment brightness sensor, an acceleration sensor, and a gyroscope.

[0230] The power supply 409 is used to supply power to various components of the heat pump unit 400. In one embodiment, the power supply 409 can be logically connected to the processor 401 through a power management system, so that the power management system can manage charging, discharging, power consumption and other functions.

[0231] Although not shown in the figure, the heat pump unit 400 may also include a camera, a Bluetooth module, etc., which will not be described in detail here.

[0232] In this embodiment, the processor 401 in the heat pump unit 400 will load instructions corresponding to the processes of one or more computer programs into the memory 402 according to the following steps, and the processor 401 will run the computer program stored in the memory 402 to achieve various functions:

[0233] Determining a target exhaust gas superheat in the heat pump unit, and determining an exhaust gas superheat in the heat pump unit;

[0234] Comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result;

[0235] Detecting the injection state of the heat pump unit;

[0236] The opening degree of the injection valve in the heat pump unit is controlled based on the comparison result and the injection state.

[0237] In one embodiment, when the processor 401 performs the above-mentioned determination of the target exhaust gas superheat in the above-mentioned heat pump unit, it can execute:

[0238] Obtaining a first calculation formula for calculating a target exhaust superheat in the heat pump unit, and determining a calculated value of the target exhaust superheat according to the first calculation formula;

[0239] Determine a target exhaust superheat value range of the target exhaust superheat;

[0240] Determine the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range;

[0241] Among them, the first calculation formula is:

[0242] DSHS=Pc / Pe*X

[0243] Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

[0244] In one embodiment, the above target exhaust superheat value range is:

[0245] DSHS min≤DSHS≤Tp_target-Tc

[0246] Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

[0247] In one implementation, when the processor 401 determines the calculated value of the target exhaust superheat according to the first calculation formula, it may execute:

[0248] Detecting the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator;

[0249] Obtaining a second calculation formula for calculating the target water temperature difference in the heat pump unit, determining the target water temperature difference of the heat pump unit according to the second calculation formula, and determining a correction coefficient corresponding to the target water temperature difference according to a first mapping relationship among the target water temperature difference, the reference target water temperature difference and the reference correction coefficient;

[0250] Calculating the calculated value of the target exhaust superheat based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula;

[0251] Among them, the second calculation formula is:

[0252] △t=Max[Min(Ts,Tstop+A)-Tw_in,B]

[0253] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, the above A is the temperature adjustment coefficient, and the above B is the temperature comparison coefficient. The above temperature adjustment coefficient and the above temperature comparison coefficient are determined based on the above heat pump inlet water temperature.

[0254] In one implementation, when the processor 401 performs the above-mentioned determination of the target exhaust gas superheat value range of the target exhaust gas superheat, it may execute:

[0255] Obtaining a heat pump set water temperature of the heat pump unit, and determining a target exhaust temperature corresponding to the heat pump set water temperature according to the heat pump set water temperature and referring to a second mapping relationship between the heat pump set water temperature and a reference target exhaust temperature;

[0256] Calculating the condensing temperature of the heat pump unit according to the condensing pressure;

[0257] Determining a preset maximum value for the target exhaust gas superheat according to the target exhaust gas temperature and the condensing temperature;

[0258] Obtaining a preset minimum value of the heat pump unit set for the target exhaust gas superheat;

[0259] The target exhaust superheat value range is determined according to the preset maximum value and the preset minimum value.

[0260] In one embodiment, when the processor 401 determines the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range, the processor 401 may execute:

[0261] If the above calculated value belongs to the above target exhaust superheat value range, then the target exhaust superheat in the above heat pump unit is the above calculated value;

[0262] If the calculated value is less than the preset minimum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset minimum value;

[0263] If the calculated value is greater than the preset maximum value in the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the preset maximum value.

[0264] In one implementation, the injection state includes a liquid injection state and an air injection state. When the processor 401 performs the above-mentioned detection of the injection state of the above-mentioned heat pump unit, it may execute:

[0265] Detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature;

[0266] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state;

[0267] If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the injection state.

[0268] In one implementation, when the processor 401 performs the above-mentioned determination of the exhaust gas superheat in the above-mentioned heat pump unit, it may execute:

[0269] The exhaust temperature of the heat pump unit is detected, the difference between the exhaust temperature and the condensing temperature is obtained, and the difference is used as the exhaust superheat.

[0270] In one embodiment, the injection state includes a liquid injection state and an air injection state. When the processor 401 controls the opening of the injection valve in the heat pump unit according to the comparison result and the injection state, the following steps may be performed:

[0271] Based on the comparison result, determining whether the exhaust gas superheat is less than the target exhaust gas superheat;

[0272] If the exhaust gas superheat is less than the target exhaust gas superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or,

[0273] If the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is the injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

[0274] An embodiment of the present application further provides a computer-readable storage medium, in which a computer program is stored. When the computer program runs on a computer, the computer executes the heat pump injection enthalpy increase control method described in any of the above embodiments.

[0275] It should be noted that, a person skilled in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a computer program, and the computer program can be stored in a computer-readable storage medium, and the storage medium can include but is not limited to: read-only memory (ROM), random access memory (RAM), disk or optical disk, etc.

[0276] In addition, the terms "first", "second", and "third" in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or modules is not limited to the listed steps or modules, but some embodiments also include steps or modules that are not listed, or some embodiments also include other steps or modules inherent to these processes, methods, products, or devices.

[0277] The above is a detailed introduction to the heat pump injection enthalpy control method, device, storage medium and heat pump unit provided in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application; at the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A heat pump injection enthalpy control method, applied to a heat pump unit, characterized in that: include: determining a target exhaust gas superheat in the heat pump unit, and determining an exhaust gas superheat in the heat pump unit; comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result; Detecting the injection state of the heat pump unit; The opening degree of the injection valve in the heat pump unit is controlled based on the comparison result and the injection state.

2. The method according to claim 1, characterized in that Determining the target exhaust gas superheat in the heat pump unit includes: Acquire a first calculation formula for calculating a target exhaust superheat in the heat pump unit, and determine a calculated value of the target exhaust superheat according to the first calculation formula; Determining a target exhaust superheat value range of the target exhaust superheat; Determining a target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range; Wherein, the first calculation formula is: DSHS=Pc / Pe*X Wherein, DSHS is the target exhaust superheat, Pc is the condensing pressure, Pe is the evaporating pressure, and X is the correction factor.

3. The method according to claim 2, characterized in that The target exhaust superheat value range is: DSHS min≤DSHS≤Tp_target-Tc Wherein, DSHS min is the preset minimum value of the target exhaust superheat, Tp_target is the target exhaust temperature, and Tc is the condensing temperature.

4. The method according to claim 2, characterized in that: Determining the calculated value of the target exhaust superheat according to the first calculation formula includes: Detecting the condensing pressure of the condenser in the heat pump unit and the evaporating pressure in the evaporator; Obtaining a second calculation formula for calculating a target water temperature difference in the heat pump unit, determining the target water temperature difference of the heat pump unit according to the second calculation formula, and determining a correction coefficient corresponding to the target water temperature difference according to a first mapping relationship among the target water temperature difference, a reference target water temperature difference, and a reference correction coefficient; Calculating the calculated value of the target exhaust superheat based on the condensing pressure, the evaporating pressure, the target correction coefficient and the first calculation formula; Wherein, the second calculation formula is: △t=Max[Min(Ts,Tstop+A)-Tw_in,B] Among them, △t is the target water temperature difference, Ts is the set water temperature of the heat pump, Tstop is the target shutdown temperature of the heat pump, Tw_in is the inlet water temperature of the heat pump, A is the temperature adjustment coefficient, and B is the temperature comparison coefficient. The temperature adjustment coefficient and the temperature comparison coefficient are determined based on the inlet water temperature of the heat pump.

5. The method according to claim 2, characterized in that: The target exhaust superheat value range for determining the target exhaust superheat includes: Acquire the heat pump set water temperature of the heat pump unit, and determine the target exhaust temperature corresponding to the heat pump set water temperature according to the heat pump set water temperature and with reference to a second mapping relationship between the heat pump set water temperature and a reference target exhaust temperature; Calculating the condensing temperature of the heat pump unit according to the condensing pressure; determining a preset maximum value for the target exhaust gas superheat according to the target exhaust gas temperature and the condensing temperature; Obtaining a preset minimum value of the heat pump unit set for the target exhaust gas superheat; The target exhaust superheat value range is determined according to the preset maximum value and the preset minimum value.

6. The method according to claim 5, characterized in that The step of determining the target exhaust gas superheat in the heat pump unit based on the calculated value and the target exhaust gas superheat value range includes: If the calculated value belongs to the target exhaust superheat value range, the target exhaust superheat in the heat pump unit is the calculated value; If the calculated value is less than the preset minimum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset minimum value; If the calculated value is greater than the preset maximum value in the target exhaust gas superheat value range, the target exhaust gas superheat in the heat pump unit is the preset maximum value.

7. The method according to claim 1, characterized in that The injection state includes a liquid injection state and an air injection state, and the detecting the injection state of the heat pump unit includes: Detecting the injection inlet temperature and the injection outlet temperature of the heat pump unit, and detecting the exhaust temperature; If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature satisfies the preset temperature range, and the exhaust temperature at the current moment is lower than the exhaust temperature at the previous moment, the current injection state is the liquid injection state; If the absolute value of the difference between the injection inlet temperature and the injection outlet temperature does not satisfy the preset temperature range, and the exhaust temperature at the current moment is greater than or equal to the exhaust temperature at the previous moment, the current injection state is the jet state.

8. The method according to claim 1, characterized in that The determining of the exhaust gas superheat in the heat pump unit comprises: detecting the exhaust gas temperature of the heat pump unit, obtaining the difference between the exhaust gas temperature and the condensing temperature, and using the difference as the exhaust gas superheat; The injection state includes a liquid injection state and an air injection state, and controlling the opening of the injection valve in the heat pump unit according to the comparison result and the injection state includes: Based on the comparison result, determining whether the exhaust gas superheat is less than the target exhaust gas superheat; If the exhaust gas superheat is less than the target exhaust gas superheat, it is determined whether the injection state of the heat pump unit is a liquid injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased; or, If the exhaust superheat is greater than or equal to the target exhaust superheat, it is determined whether the injection state of the heat pump unit is an injection state; if so, the opening of the injection valve is reduced; if not, the opening of the injection valve is increased.

9. A heat pump jet enthalpy control device, characterized in that: include: a determination module, used to determine a target exhaust gas superheat in the heat pump unit, and to determine the exhaust gas superheat in the heat pump unit; A comparison module, used for comparing the exhaust gas superheat with the target exhaust gas superheat to obtain a comparison result; A detection module, used for detecting the injection state of the heat pump unit; A control module is used to control the opening of the injection valve in the heat pump unit based on the comparison result and the injection state.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed on a computer, the computer is enabled to execute the heat pump injection enthalpy increase control method according to any one of claims 1 to 8.

11. A heat pump unit, comprising a processor and a memory, wherein the memory stores a computer program, characterized in that: The processor is used to execute the heat pump injection enthalpy increase control method as described in any one of claims 1 to 8 by calling the computer program.

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