Control methods for heat pump systems, heat pump systems and storage media

Abstract

This invention discloses a control method for a heat pump system, the heat pump system itself, and a storage medium. The heat pump system includes a main refrigerant circuit and refrigerant branch circuits connected to the main circuit. The main refrigerant circuit includes an indoor heat exchanger and a compressor, and the refrigerant branch circuits include an energy storage device. The method includes: when the heat pump system starts in a preset mode, acquiring the energy demand parameters of the energy storage device; controlling the operating frequency of the compressor based on the energy demand parameters; when the heat pump system reaches preset operating conditions, acquiring the system pressure of the heat pump system; and controlling the operating frequency of the compressor based on the system pressure. In the preset mode, the indoor heat exchanger is not in heat exchange mode, and the energy storage device is in energy storage mode. This invention aims to achieve rapid energy storage while improving the timeliness of compressor frequency adjustment, thereby improving the energy storage effect.

Description

Technical Field

[0001] This invention relates to the field of heat pump technology, and more particularly to a control method for a heat pump system, a heat pump system, and a storage medium. Background Technology

[0002] In addition to using energy to regulate the indoor environment, heat pump systems also include energy storage devices such as water tanks to provide energy for other needs. Typically, heat pump systems have a separate energy storage mode, in which indoor air conditioning is stopped, and energy is stored solely in the energy storage device.

[0003] In standalone energy storage mode, heat pump systems typically regulate the compressor's operating frequency based on the outdoor ambient temperature and the temperature of the energy storage device to achieve rapid energy storage. However, temperature regulation has a lag, which can easily lead to untimely compressor frequency regulation and affect the energy storage effect of the energy storage device. Summary of the Invention

[0004] The main objective of this invention is to provide a control method for a heat pump system, a heat pump system, and a storage medium, aiming to achieve rapid energy storage while improving the timeliness of compressor frequency regulation, thereby enhancing the energy storage effect.

[0005] To achieve the above objectives, the present invention provides a control method for a heat pump system, the heat pump system comprising a refrigerant main circuit and refrigerant branch circuits connected to the refrigerant main circuit, the refrigerant main circuit comprising an indoor heat exchanger and a compressor, and the refrigerant branch circuits comprising an energy storage device, the control method for the heat pump system comprising the following steps:

[0006] When the heat pump system starts the preset mode, the energy demand parameters of the energy storage device are obtained;

[0007] The operating frequency of the compressor is controlled according to the energy demand parameters;

[0008] When the heat pump system reaches the preset operating conditions, the system pressure of the heat pump system is obtained;

[0009] The operating frequency of the compressor is controlled according to the system pressure;

[0010] In the preset mode, the indoor heat exchanger is not in heat exchange state, and the energy storage device is in energy storage state.

[0011] Optionally, the step of controlling the operating frequency of the compressor according to the energy demand parameters includes:

[0012] The energy requirement parameters are adjusted according to the target correction value to obtain the initial frequency of the compressor;

[0013] Control the compressor to operate at the initial frequency;

[0014] The target correction value is determined based on the exhaust parameters of the compressor.

[0015] Optionally, the step of obtaining the energy demand parameters of the energy storage device includes:

[0016] Obtain the actual energy demand of the energy storage device under the current operating conditions and the rated energy demand of the energy storage device;

[0017] The energy demand parameter is determined based on the actual energy demand and the rated energy demand.

[0018] Optionally, the step of obtaining the actual energy demand of the energy storage device under the current operating conditions includes:

[0019] Obtain the energy storage temperature of the energy storage device and the corresponding outdoor ambient temperature of the heat pump system;

[0020] The actual energy demand is determined based on the energy storage temperature and the outdoor ambient temperature.

[0021] Optionally, the step of obtaining the rated energy demand includes:

[0022] Obtain the volume of the energy storage device used to store the energy storage material;

[0023] The rated energy requirement is determined based on the volume.

[0024] Optionally, the step of controlling the operating frequency of the compressor based on the system pressure includes:

[0025] The operating frequency of the compressor is controlled based on the system pressure and the target pressure of the heat pump system;

[0026] The target pressure is determined based on the energy storage temperature of the energy storage device.

[0027] Optionally, if the target pressure is defined as Tm and the energy storage temperature as Tw, then the target pressure and the energy storage temperature satisfy the following quantitative relationship:

[0028] T m =a*T w 2 +b*T w +c, where a, b, and c are constants.

[0029] Optionally, the step of controlling the operating frequency of the compressor based on the system pressure and the target pressure of the heat pump system includes:

[0030] Determine the pressure difference between the target pressure and the system pressure;

[0031] When the pressure difference is greater than the first threshold, the compressor is controlled to increase its operating frequency;

[0032] When the pressure difference is less than or equal to the second threshold, the compressor is controlled to reduce its operating frequency.

[0033] Wherein, the second threshold is less than or equal to the first threshold.

[0034] Optionally, after the step of controlling the operating frequency of the compressor according to the system pressure, the method further includes:

[0035] The target duration is determined based on the deviation between the target pressure of the heat pump system and the system pressure, and the target duration is negatively correlated with the deviation.

[0036] After the target time interval, return to the step of obtaining the system pressure of the heat pump system.

[0037] In addition, to achieve the above objectives, this application also proposes a heat pump system, which includes a control device, a refrigerant main circuit and a refrigerant branch circuit, wherein the refrigerant main circuit includes an indoor heat exchanger and a compressor, and the refrigerant branch circuit includes an energy storage device.

[0038] The compressor is connected to the control device, which includes a memory, a processor, and a control program for the heat pump system stored in the memory and executable on the processor. When the control program for the heat pump system is executed by the processor, it implements the steps of the control method for the heat pump system as described in any of the preceding claims.

[0039] In addition, to achieve the above objectives, this application also proposes a storage medium storing a control program for a heat pump system, which, when executed by a processor, implements the steps of the control method for the heat pump system as described in any of the preceding claims.

[0040] This invention proposes a control method for a heat pump system. Based on a heat pump system including a refrigerant main circuit and refrigerant branch circuits, with an energy storage device installed in the refrigerant branch circuit, this method, after the heat pump system starts in a preset mode, no longer adjusts the compressor's operating frequency according to the outdoor ambient temperature and the temperature of the energy storage device. Instead, in the initial stage, the compressor's operating frequency is controlled based on the energy demand of the energy storage device. At this time, the energy demand of the energy storage device is relatively large, and adjusting the frequency according to the energy demand is conducive to achieving rapid energy storage. After the heat pump system reaches the preset operating conditions, the compressor's operating frequency is adjusted according to the system pressure. Since the current energy storage effect of the system can be accurately characterized by the system pressure, controlling the compressor's operating frequency according to the system pressure can achieve rapid energy storage while improving the timeliness of compressor frequency adjustment, thereby improving the energy storage effect. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the refrigerant flow path structure in one embodiment of the heat pump system of the present invention;

[0042] Figure 2 This is a schematic diagram of the hardware structure involved in the operation of an embodiment of the heat pump system of the present invention;

[0043] Figure 3 This is a flowchart illustrating an embodiment of the control method for the heat pump system of the present invention;

[0044] Figure 4 This is a schematic flowchart of another embodiment of the control method for the heat pump system of the present invention;

[0045] Figure 5 This is a flowchart illustrating another embodiment of the control method for the heat pump system of the present invention;

[0046] Figure 6 This is a flowchart illustrating another embodiment of the control method for the heat pump system of the present invention.

[0047] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0048] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0049] This invention provides a heat pump system.

[0050] In this embodiment of the invention, reference is made to Figure 1 and Figure 2 The heat pump system includes a control device 100, a refrigerant main circuit, and refrigerant branch circuits connected to the refrigerant main circuit. The refrigerant main circuit includes a compressor 1, an indoor unit, an outdoor heat exchanger 3, a throttling device 4, and a reversing assembly 5. The refrigerant branch circuits include an energy storage device 7 and a first control valve 8. The indoor unit, the reversing assembly 5, the compressor 1, the throttling device 4, and the first control valve 8 are all connected to the control device 100. Both the throttling device 4 and the first control valve 8 can be electronic expansion valves.

[0051] In this embodiment, the energy storage device 7 includes a water tank (e.g., a water heater), and external water-using equipment can be connected to the water tank to utilize the water containing energy stored in the energy storage device 7. In other embodiments, the energy storage device 7 may also include other types of devices with energy storage functions. When the refrigerant in the refrigerant branch flows through the energy storage device 7, it can exchange heat with the energy storage material therein, and the energy storage material can absorb and store the energy flowing through the refrigerant.

[0052] In one implementation of this embodiment, one end of the refrigerant branch is connected to the exhaust port of the compressor 1, and the pipeline between the indoor unit and the outdoor heat exchanger 3 is connected to the other end of the refrigerant branch.

[0053] In another implementation of this embodiment, the heat pump system may also be equipped with a flow direction regulating component. The pipeline between the indoor unit and the outdoor heat exchanger 3 is connected to the second end of the refrigerant branch. The return port of the compressor 1, the exhaust port of the compressor 1, and the first end of the refrigerant branch are all connected to the flow direction regulating component. The refrigerant branch switches between two states: being connected to the return port of the compressor 1 and being connected to the exhaust port of the compressor 1, through the flow direction regulating component. One end of the refrigerant branch is connected to the exhaust port of the compressor 1.

[0054] In this embodiment, there is more than one indoor unit, which can be connected in parallel. In other embodiments, there may be only one indoor unit.

[0055] The indoor unit includes an indoor heat exchanger 21 and a second control valve 22 connected in series with the indoor heat exchanger 21. The second control valve 22 is connected to a control device 100, which can be used to control the refrigerant flow through the indoor heat exchanger 21. The second control valve 22 can be an electronic expansion valve.

[0056] The indoor unit, throttling device 4, and outdoor heat exchanger 3 are connected in sequence. The pipe between the throttling device 4 and the indoor unit is connected to one end of the refrigerant branch. The exhaust port of the indoor unit, outdoor heat exchanger 3, and compressor 1, as well as the return port of compressor 1, are all connected to the reversing assembly 5. The reversing assembly 5 can be used to switch the connection status between the indoor unit and outdoor heat exchanger 3 and the exhaust port and return port of compressor 1.

[0057] In this embodiment, the reversing assembly 5 includes a first reversing valve 51 and a second reversing valve 52. The exhaust port of the compressor 1, the return port of the compressor 1, and the indoor unit are respectively connected to different valve ports of the first reversing valve 51, and the exhaust port of the compressor 1, the return port of the compressor 1, and the outdoor heat exchanger 3 are respectively connected to different valve ports of the second reversing valve 52. In one implementation of this embodiment, the first reversing valve 51 is a first four-way valve, and the second reversing valve 52 is a second four-way valve. In another implementation of this embodiment, the first reversing valve 51 is a first three-way valve, and the second reversing valve 52 is a second three-way valve.

[0058] The first reversing valve 51 has a first valve position and a second valve position. When the first reversing valve 51 is in the first valve position, the return port of the compressor 1 is connected to the indoor heat exchanger 21, and the exhaust port of the compressor 1 is blocked from the indoor heat exchanger 21. When the first reversing valve 51 is in the second valve position, the return port of the compressor 1 is blocked from the indoor heat exchanger 21, and the exhaust port of the compressor 1 is connected to the indoor heat exchanger 21.

[0059] The second reversing valve 52 has a third valve position and a fourth valve position. When the second reversing valve 52 is in the third valve position, the exhaust port of the compressor 1 is connected to the outdoor heat exchanger 3, and the return port of the compressor 1 is blocked from the outdoor heat exchanger 3. When the second reversing valve 52 is in the fourth valve position, the exhaust port of the compressor 1 is blocked from the outdoor heat exchanger 3, and the return port of the compressor 1 is connected to the outdoor heat exchanger 3.

[0060] In some embodiments, the reversing assembly 5 may further include a switching valve (not shown), which can be used to switch the connection state between the energy storage device 7 and the discharge port and return port of the compressor 1. The switching valve can be a three-way valve or a four-way valve, and the switching valve includes a first switching state and a second switching state; when the switching valve is in the first switching state, the return port of the compressor 1 is connected to the energy storage device 7; when the switching valve is in the second switching state, the discharge port of the compressor 1 is connected to the energy storage device 7.

[0061] Through the adjustment of the first reversing valve 51, the second reversing valve 52, the first control valve 8, and the second control valve 22, the operating modes of the heat pump system include, but are not limited to, the following modes:

[0062] In the first mode, refer to Figure 1 The first reversing valve 51 operates in the first valve position, the second reversing valve 52 operates in the fourth valve position, the second control valve 22 is closed, and the first control valve 8 is open. The refrigerant branch is connected to the exhaust port of the compressor 1 (when the reversing assembly 5 includes a switching valve, the switching valve is in the second switching state). All the refrigerant discharged from the compressor 1 flows into the refrigerant branch. The refrigerant flowing into the refrigerant branch stores heat in the energy storage device 7 as it flows through the energy storage device 7. The refrigerant flowing out of the refrigerant branch flows through the throttling device 4 and the outdoor heat exchanger 3 in sequence before returning to the compressor 1. In the first mode, the indoor heat exchanger 21 stops exchanging heat, the outdoor heat exchanger 3 is in an evaporating state, and the energy storage device 7 is in a condensing state. All heat is used for heat storage in the energy storage device 7. In the first mode, the energy storage device 7 can store heat independently.

[0063] In the second mode, the first reversing valve 51 operates in the first valve position, the second reversing valve 52 operates in the third valve position, the first control valve 8 is open, and the second control valve 22 is open. The refrigerant branch is connected to the exhaust port of the compressor 1 (when the reversing assembly 5 includes a switching valve, the switching valve is in the second switching state). A portion of the refrigerant discharged from the compressor 1 flows sequentially through the outdoor heat exchanger 3 and the throttling device 4, while another portion of the refrigerant discharged from the compressor 1 flows into the refrigerant branch. The refrigerant flowing into the refrigerant branch stores heat in the energy storage device 7 as it flows through the energy storage device 7. The refrigerant flowing out of the refrigerant branch merges with the refrigerant flowing out of the throttling device 4 and flows into the indoor unit for evaporation before returning to the compressor 1. In the second mode, the indoor heat exchanger 21 is in the evaporation state, and the outdoor heat exchanger 3 is in the condensation state. In the second mode, when the indoor space regulated by the indoor unit has a heat exchange requirement, the indoor fan in the indoor unit can be turned on to drive the indoor air to exchange heat with the indoor heat exchanger 21; when the indoor space regulated by the indoor unit does not have a heat exchange requirement, the indoor fan in the indoor unit can be turned off. In the second mode, the heat absorbed by the outdoor heat exchanger 3 from its environment can be stored in the energy storage device 7. In the second mode, the energy storage device 7 can store heat during the cooling process of the indoor environment, or the oil in the compressor 1 in the refrigerant branch can be returned to the compressor 1 while the energy storage device 7 stores heat.

[0064] In the third mode, the first reversing valve 51 operates in the first valve position, the second reversing valve 52 operates in the fourth valve position, the first control valve 8 is open, and the second control valve 22 operates at a throttling rate. The refrigerant branch is connected to the discharge port of the compressor 1 (when the reversing assembly 5 includes a switching valve, the switching valve is in the second switching state). All the refrigerant discharged from the compressor 1 flows into the refrigerant branch. The heat of the refrigerant flowing into the refrigerant branch is stored in the energy storage device 7 as it flows through the energy storage device 7. A portion of the refrigerant flowing out of the refrigerant branch flows through the throttling device 4 and the outdoor heat exchanger 3 in sequence before returning to the compressor 1. Another portion of the refrigerant flowing out of the refrigerant branch flows through the second control valve 22 and the indoor heat exchanger 21 in sequence before returning to the compressor 1. In the third mode, both the indoor heat exchanger 21 and the outdoor heat exchanger 3 are in an evaporating state. In the third mode, when the indoor space regulated by the indoor unit has a heat exchange requirement, the indoor fan in the indoor unit can be turned on to drive the indoor air to exchange heat with the indoor heat exchanger 21; when the indoor space regulated by the indoor unit does not have a heat exchange requirement, the indoor fan in the indoor unit can be turned off. In the third mode, the heat absorbed by the indoor heat exchanger 21 and the outdoor heat exchanger 3 from their respective environments can be stored in the energy storage device 7. In the third mode, the indoor environment can be cooled while the energy storage device 7 stores heat.

[0065] In the fourth mode, the first reversing valve 51 operates in the first valve position, the second reversing valve 52 operates in the third valve position, the first control valve 8 is closed, and the second control valve 22 is open. The refrigerant discharged from the compressor 1 flows sequentially through the outdoor heat exchanger 3, the throttling device 4, the second control valve 22, and the indoor heat exchanger 21 before returning to the compressor 1. In the fourth mode, the indoor heat exchanger 21 is in an evaporating state, and the outdoor heat exchanger 3 is in a condensing state. When the indoor space regulated by the indoor unit in the fourth mode has a heat exchange requirement, the indoor fan in the indoor unit can be turned on to drive the indoor air to exchange heat with the indoor heat exchanger 21; when the indoor space regulated by the indoor unit in the fourth mode does not have a heat exchange requirement, the indoor fan in the indoor unit can be turned off. In the fourth mode, the indoor environment can be cooled while the energy storage device 7 stops storing heat.

[0066] In other embodiments, the reversing assembly 5 may also include a third four-way valve, with the exhaust port of the compressor 1, the return port of the compressor 1, the indoor heat exchanger 21 and the outdoor heat exchanger 3 respectively connected to different ports of the third four-way valve.

[0067] Furthermore, refer to Figures 1 to 2 The heat pump system also includes a pressure sensor 01, which can be located on the exhaust side of the compressor 1 to detect the condensing pressure of the heat pump system. The pressure sensor 01 is connected to the control device 100.

[0068] Furthermore, refer to Figure 2 The heat pump system also includes a temperature detection module 02, which is connected to the control device 100. The temperature detection module 02 can be located inside the energy storage device 7 to detect the energy storage temperature of the energy storage device 7.

[0069] Furthermore, refer to Figure 2 The heat pump system also includes an environmental monitoring module 03, which is connected to the control device 100. The environmental monitoring module 03 can be installed in the outdoor environment to monitor the outdoor ambient temperature.

[0070] In this embodiment of the invention, reference is made to Figure 2 The control unit of the heat pump system includes a processor 1001, such as a CPU, a memory 1002, and a timer 1003. These components communicate with each other via a communication bus. The memory 1002 can be high-speed RAM or non-volatile memory, such as disk storage. Optionally, the memory 1002 can also be a storage device independent of the aforementioned processor 1001.

[0071] Those skilled in the art will understand that Figure 2The device structure shown does not constitute a limitation on the device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0072] like Figure 2 As shown, the memory 1002, which serves as a computer storage medium, may include a control program for a heat pump system.

[0073] exist Figure 2 In the device shown, the processor 1001 can be used to call the control program of the heat pump system stored in the memory 1002 and execute the relevant steps of the control method of the heat pump system in the following embodiments.

[0074] This invention also provides a control method for a heat pump system, applied to the aforementioned heat pump system.

[0075] Reference Figure 3 This application proposes an embodiment of a control method for a heat pump system. In this embodiment, the control method for the heat pump system includes:

[0076] Step S10: When the heat pump system starts a preset mode, the energy demand parameters of the energy storage device are obtained; wherein, in the preset mode, the indoor heat exchanger is not in heat exchange state and the energy storage device is in energy storage state.

[0077] In this embodiment, the compressor's exhaust port is connected to one end of the refrigerant branch, and the preset mode is the first mode described above, which is the independent heat storage mode. In other embodiments, the compressor's return port is connected to one end of the refrigerant branch, and the preset mode is also the independent cold storage mode.

[0078] The energy demand parameter is specifically a state parameter that characterizes the energy storage device's demand for compressor output capacity in a preset mode.

[0079] Energy requirements can be determined based on the detection data inside the energy storage device and / or the detection data of the environment where the heat pump system is located.

[0080] After the heat pump system starts in the preset mode, if the heat pump system does not meet the preset conditions, the energy demand parameters can be acquired at first intervals, and the operating frequency of the compressor can be controlled according to the energy demand parameters until the heat pump system runs to meet the preset conditions.

[0081] Step S20: Control the operating frequency of the compressor according to the energy demand parameters;

[0082] In one implementation of this embodiment, the target operating frequency of the compressor is determined based on the energy demand parameters, and the compressor is controlled to operate at the target frequency.

[0083] In another implementation of this embodiment, the frequency adjustment value of the compressor is determined according to the energy demand parameters, and the compressor is controlled to adjust the current frequency according to the frequency adjustment value.

[0084] In another implementation of this embodiment, the frequency limit value of the compressor is determined according to the energy demand parameters, and the compressor is controlled to operate at a frequency within the frequency range limited by the frequency limit value.

[0085] Step S30: When the heat pump system reaches the preset operating conditions, obtain the system pressure of the heat pump system;

[0086] The preset conditions can characterize the heat pump system's own operating parameters and / or the environmental state parameters of the environment in which the heat pump system is located when the preset mode is started and reaches a stable operating state.

[0087] In this embodiment, the preset conditions include a runtime greater than or equal to a preset duration after the preset mode is activated. In other embodiments, the preset conditions may also include a temperature change value of the energy storage device greater than or equal to a preset change value.

[0088] In this embodiment, one end of the refrigerant branch is connected to the compressor's exhaust port, and the system pressure is high pressure, specifically detected by the aforementioned pressure sensor. In other embodiments, the system pressure may also be low pressure.

[0089] Step S40: Control the operating frequency of the compressor according to the system pressure.

[0090] In one implementation of this embodiment, the target operating frequency of the compressor is determined based on the system pressure, and the compressor is controlled to operate at the target frequency.

[0091] In another implementation of this embodiment, the compressor frequency adjustment value is determined based on the system pressure, and the compressor is controlled to adjust the current frequency according to the frequency adjustment value.

[0092] In another implementation of this embodiment, the frequency limit value of the compressor is determined based on the system pressure, and the compressor is controlled to operate at a frequency within the frequency range limited by the frequency limit value.

[0093] Here, after the preset mode is activated, when the heat pump system has not yet reached the preset conditions, it is in the initial stage of the preset mode. At this time, the heat pump system has not reached a stable operating state, and the energy demand of the energy storage device is relatively large. At this time, the frequency of the compressor is adjusted according to the energy demand, which is conducive to rapid energy storage while improving the operational stability of the heat pump system. When the heat pump system reaches the preset conditions, it is in the normal operating stage of the preset mode. At this time, the heat pump system has reached a stable operating state, and the energy demand of the energy storage device has decreased. At this time, the compressor frequency is adjusted according to the system pressure, which is conducive to improving the timeliness and accuracy of the compressor operating frequency adjustment, thereby ensuring that the energy storage device can accurately and quickly reach the required energy storage capacity and improve the energy storage effect.

[0094] The present invention proposes a control method for a heat pump system. After the heat pump system starts in a preset mode, the operating frequency of the compressor is no longer fixedly adjusted according to the outdoor ambient temperature and the temperature of the energy storage device. Instead, in the initial stage, the operating frequency of the compressor is controlled based on the energy demand of the energy storage device. At this time, the energy demand of the energy storage device is relatively large, and adjusting the frequency according to the energy demand is conducive to achieving rapid energy storage. After the heat pump system reaches the preset conditions, the operating frequency of the compressor is adjusted according to the system pressure. Since the current energy storage effect of the system can be accurately characterized by the system pressure, controlling the operating frequency of the compressor according to the system pressure can achieve rapid energy storage while improving the timeliness of compressor frequency adjustment, thereby improving the energy storage effect.

[0095] Furthermore, based on the above embodiments, another embodiment of the control method for the heat pump system of this application is proposed. In this embodiment, reference is made to... Figure 4 Step S20 includes:

[0096] Step S21: Correct the energy demand parameter according to the target correction value to obtain the initial frequency of the compressor; wherein, the target correction value is determined according to the exhaust parameters of the compressor;

[0097] Exhaust parameters include exhaust pressure and / or exhaust temperature, etc. These parameters can be specifically obtained through a detection module located on the compressor exhaust side or calculated based on the detection data from that module, etc.

[0098] The exhaust parameters can be the current exhaust parameters of the compressor. Alternatively, the exhaust parameters can be determined based on multiple exhaust characteristic parameters of the compressor detected after startup in a preset mode.

[0099] Different exhaust parameters correspond to different target correction values.

[0100] In this embodiment, the target correction value is the correction coefficient, and the product of the energy requirement parameter and the correction coefficient is used as the initial frequency.

[0101] In other embodiments, the target correction value may also be the correction magnitude, with the sum of the required parameters and the correction magnitude used as the initial frequency.

[0102] Step S22: Control the compressor to operate at the initial frequency.

[0103] In this embodiment, during the initial operation phase of the preset mode, the energy demand parameters are corrected according to the target correction value determined by the compressor's exhaust parameters to obtain the compressor's operating frequency during this phase. This is beneficial for rapid energy storage while improving the compressor's operational reliability.

[0104] Furthermore, based on any of the above embodiments, another embodiment of the control method for the heat pump system of this application is proposed. In this embodiment, reference is made to... Figure 5 The step of obtaining the energy demand parameters of the energy storage device includes:

[0105] Step S11: Obtain the actual energy demand of the energy storage device under the current operating conditions and the rated energy demand of the energy storage device;

[0106] The actual energy demand is related to the actual operating conditions of the energy storage device and can change with the actual operating conditions.

[0107] Rated energy demand is the energy demand value that is related to the inherent properties of the energy storage device and does not change with actual operating conditions.

[0108] Step S12: Determine the energy demand parameter based on the actual energy demand value and the rated energy demand value.

[0109] In this embodiment, the sum of the actual energy demand and the rated energy demand is determined as the energy demand parameter. In other embodiments, the rated energy demand can be used to determine a correction factor, and the actual energy demand can be corrected according to the correction factor to obtain the energy demand parameter.

[0110] In this embodiment, the energy demand parameters of the energy storage device are determined by combining the actual energy demand value and the rated energy demand value. This helps to ensure that the determined energy demand parameters can accurately reflect the capacity requirements of the energy storage device in the initial stage, thereby further improving the accuracy of compressor operating frequency regulation and further improving the energy storage efficiency in the initial stage of the preset mode.

[0111] In other embodiments, either the actual energy requirement or the rated energy requirement may be used as the energy requirement parameter.

[0112] Furthermore, in this embodiment, the process of obtaining the actual energy demand is as follows: obtaining the energy storage temperature of the energy storage device and the outdoor ambient temperature corresponding to the heat pump system; determining the actual energy demand based on the energy storage temperature and the outdoor ambient temperature.

[0113] The energy storage temperature is detected by the aforementioned temperature sensor. The outdoor ambient temperature is detected by the aforementioned environmental monitoring module.

[0114] Different energy storage temperatures and different outdoor ambient temperatures correspond to different actual energy demands. Actual energy demand is negatively correlated with outdoor ambient temperature, and also negatively correlated with energy storage temperature.

[0115] Specifically, a correspondence between energy storage temperature, outdoor ambient temperature and actual energy demand can be established in advance. This correspondence can include calculation formulas, mapping relationships, etc. Based on this correspondence, the actual energy demand corresponding to the current energy storage temperature and outdoor ambient temperature can be determined.

[0116] Furthermore, there can be more than one pre-set correspondence between energy storage temperature, outdoor ambient temperature and actual energy demand. The target correspondence can be determined from the more than one correspondence based on the operating speed of the outdoor fan corresponding to the outdoor heat exchanger and the temperature difference between the energy storage temperature and the target temperature. Based on the target correspondence, the actual energy demand corresponding to the current energy storage temperature and outdoor ambient temperature can be determined.

[0117] For example, the correspondence between outdoor ambient temperature T4, energy storage temperature Tw, and actual energy demand Aw is shown in Table 1 below:

[0118]

[0119]

[0120] Table 1

[0121] Based on this, by determining the range of outdoor ambient temperature in the table above and the range of energy storage temperature in the table above, the energy demand value obtained by matching the two ranges is taken as the actual energy demand value.

[0122] In this embodiment, the combination of outdoor ambient temperature and energy storage temperature can accurately reflect the operating conditions of the preset mode. Therefore, adapting the actual energy demand value to outdoor ambient temperature and energy storage temperature helps to ensure that the actual energy demand value can accurately reflect the actual energy demand of the energy storage device under the current operating conditions, thereby further improving the accuracy of compressor frequency operation control and improving the energy storage efficiency of the energy storage device.

[0123] In other embodiments, the actual energy demand can be determined based on either the outdoor ambient temperature or the energy storage temperature, or based on other parameters besides the outdoor ambient temperature and the energy storage temperature. These other parameters may be, for example, the temperature difference between the energy storage temperature and the set temperature of the energy storage device, and / or the temperature change rate of the outdoor heat exchanger, and / or the temperature difference between the inner and outer surface temperatures of the energy storage device, and / or the temperature change rate between the inner and outer surface temperatures of the energy storage device, etc.

[0124] Furthermore, in this embodiment, the volume of the energy storage device used to store the energy storage material is obtained; the rated energy demand is determined based on the volume. The volume and the rated energy demand are positively correlated.

[0125] For example, the volume and rated energy requirement can be shown in Table 2 below:

[0126] Volume / L Rated energy demand (Hw / kW) 150 2.8 200 3.6

[0127] Table 2

[0128] In this embodiment, the rated energy demand is determined by the volume of the energy storage device, which helps to accurately reflect the energy demand required by the energy storage device itself during the energy storage process. This helps to further improve the accuracy of compressor frequency operation control and improve the energy storage efficiency of the energy storage device.

[0129] In other embodiments, the rated energy requirement can also be determined based on factors such as the casing thickness and material type of the energy storage device.

[0130] Furthermore, based on any of the above embodiments, another embodiment of the control method for the heat pump system of this application is proposed. In this embodiment, reference is made to... Figure 6 Step S40 includes:

[0131] Step S41: Control the operating frequency of the compressor according to the system pressure and the target pressure of the heat pump system; wherein the target pressure is determined according to the energy storage temperature of the energy storage device.

[0132] Determine the magnitude or quantitative relationship (e.g., ratio or difference) between the system pressure and the target pressure. Based on this relationship, determine the compressor frequency adjustment value. Adjust the compressor's operating frequency according to the frequency adjustment value to obtain the compressor's target operating frequency, and control the compressor to operate at the target frequency.

[0133] Different energy storage temperatures correspond to different target pressures. In this embodiment, the energy storage temperature and the target pressure are positively correlated. A correspondence between energy storage temperature and target pressure is established in advance. This correspondence may include quantitative relationships, mapping relationships, etc. Based on this correspondence, the target pressure corresponding to the current energy storage temperature can be determined.

[0134] In this embodiment, the target pressure is defined as Tm and the energy storage temperature as Tw. The target pressure and the energy storage temperature satisfy the following quantitative relationship: T m =a*T w 2 +b*T w+c, where a, b, and c are constants. The value of a ranges from [0.001, 0.003], the value of b ranges from [0.5, 0.8], and the value of c ranges from [18, 22]. Based on this, the target pressure can be calculated by substituting the energy storage temperature into the above quantitative relationship.

[0135] In other embodiments, a mapping table between the target pressure and the energy storage temperature can be established in advance, and the target pressure can be obtained by querying the mapping table based on the energy storage temperature.

[0136] In this embodiment, adjusting the compressor's operating frequency based on the target pressure and system pressure determined by the energy storage temperature helps improve the accuracy of the target pressure. This ensures that adjusting the compressor's operating frequency based on the target pressure and system pressure effectively improves the timeliness and accuracy of the frequency control, guaranteeing that the compressor's output capacity precisely matches the energy storage requirements of the energy storage device, thereby further improving the energy storage effect. Specifically, when the target pressure and energy storage temperature satisfy the aforementioned quantitative relationship, it further enhances the accuracy of the target pressure, thus improving the energy storage effect. Furthermore, when a, b, and c are set according to the above parameter range, as the energy storage temperature increases, the increase in the target pressure corresponding to the preset range of energy storage temperature change tends to decrease. That is, when the energy storage temperature is low, the increase in target pressure is larger when the energy storage temperature increases by the preset range, and when the energy storage temperature is high, the increase in target pressure is smaller when the energy storage temperature increases by the preset range. Based on this, it is beneficial to ensure that the system high pressure can be rapidly increased in the initial stage of the preset mode to effectively ensure that there is enough heat for the energy storage device to store heat. After the temperature of the energy storage device has increased to a certain extent, the system high pressure can be increased slowly, which is beneficial to the rapid heat storage efficiency while further improving the operational stability of the heat pump system.

[0137] Furthermore, in this embodiment, the step of controlling the operating frequency of the compressor based on the system pressure and the target pressure of the heat pump system includes: determining the pressure difference between the target pressure and the system pressure; when the pressure difference is greater than a first threshold, controlling the compressor to increase its operating frequency; when the pressure difference is less than or equal to a second threshold, controlling the compressor to decrease its operating frequency; wherein the second threshold is less than or equal to the first threshold.

[0138] In this embodiment, the second threshold is less than the first threshold. The first threshold is greater than 0, and the second threshold is less than 0.

[0139] The pressure difference is the result of subtracting the system pressure from the target pressure. When the target pressure is greater than the system pressure, the pressure difference is greater than 0; when the target pressure is less than the system pressure, the pressure difference is less than 0.

[0140] When the compressor increases or decreases its operating frequency, the compressor's frequency adjustment value can be a preset fixed value or a value determined based on the actual operating state of the heat pump system. For example, the frequency adjustment value can be determined based on the opening degree of the first control valve and / or the temperature of the refrigerant heat dissipation module set between the first control valve and the throttling device and / or the temperature difference between the outdoor heat exchanger temperature and the outdoor ambient temperature. The refrigerant heat dissipation module is used to dissipate heat from the heat-generating components. The frequency adjustment value determined based on this is beneficial to further improve the accuracy of the compressor's operating frequency adjustment, thereby improving the energy storage effect while preventing condensation on the cooling module.

[0141] In this embodiment, adjusting the compressor's operating frequency according to the pressure difference between the target pressure and the system pressure helps ensure that the system pressure can accurately reach the target pressure after the compressor's operating frequency is adjusted, thereby further improving the energy storage effect.

[0142] Furthermore, based on any of the above embodiments, another optional embodiment of the control method for the heat pump system of this application is proposed. In this embodiment, after step S40, the method further includes:

[0143] Step S50: Determine the target duration based on the deviation between the target pressure of the heat pump system and the system pressure, wherein the target duration is negatively correlated with the deviation.

[0144] The target pressure here is the same concept as the target pressure mentioned above. The deviation here is the absolute value of the pressure difference mentioned above. For example, the relationship between the target duration and the pressure difference X is shown in Table 3 below:

[0145] Pressure difference (Pa) X＜-3 -3≤X＜-2 -2≤X＜-1 -1≤X＜1 1≤X＜2 2≤X＜3 X≥3 Target duration (seconds) 30 60 120 180 120 90 60

[0146] Table 3

[0147] As shown in Table 3, the positive and negative values ​​of the pressure difference can indicate the relationship between the target pressure and the system pressure. When the target pressure is greater than the system pressure or less than the preset pressure, the larger the deviation, the shorter the target duration, and the smaller the deviation, the longer the target duration.

[0148] Step S60: After the target time interval, return to the step of obtaining the system pressure of the heat pump system.

[0149] In this embodiment, the interval adjustment cycle of the compressor operating frequency is determined based on the deviation between the target pressure and the system pressure. This helps to ensure that the system pressure accurately reaches the target pressure while reducing unnecessary adjustments to the compressor frequency, thereby improving the energy storage effect of the heat pump system and enhancing the operating stability of the compressor.

[0150] Furthermore, embodiments of the present invention also propose a storage medium storing a control program for a heat pump system. When the control program for the heat pump system is executed by a processor, it implements the relevant steps of any embodiment of the control method for the heat pump system described above.

[0151] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0152] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0153] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, heat pump system, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0154] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A control method for a heat pump system, characterized in that, The heat pump system includes a refrigerant main circuit and refrigerant branch circuits connected to the refrigerant main circuit. The refrigerant main circuit includes an indoor heat exchanger and a compressor. The refrigerant branch circuits include an energy storage device. The control method of the heat pump system includes the following steps: When the heat pump system starts the preset mode, the energy demand parameters of the energy storage device are obtained. The energy demand parameters are state parameters that characterize the energy storage device’s demand for compressor output capacity in the preset mode. The operating frequency of the compressor is controlled according to the energy demand parameters; When the heat pump system reaches the preset conditions, the system pressure of the heat pump system is obtained. The preset conditions represent the heat pump system's own operating parameters and / or the environmental state parameters of the environment where the heat pump system is located when it reaches a stable operating state after the preset mode is started. The operating frequency of the compressor is controlled based on the system pressure and the target pressure of the heat pump system; In the preset mode, the indoor heat exchanger is not in heat exchange state and the energy storage device is in energy storage state. The target pressure is defined as Tm and the energy storage temperature as Tw. The target pressure and the energy storage temperature satisfy the following quantitative relationship: T m =a*T w 2 +b*T w +c, where a, b, and c are constants.

2. The control method for a heat pump system as described in claim 1, characterized in that, The step of controlling the operating frequency of the compressor according to the energy demand parameters includes: The energy requirement parameters are adjusted according to the target correction value to obtain the initial frequency of the compressor; Control the compressor to operate at the initial frequency; The target correction value is determined based on the exhaust parameters of the compressor.

3. The control method for a heat pump system as described in claim 1, characterized in that, The step of obtaining the energy demand parameters of the energy storage device includes: Obtain the actual energy demand of the energy storage device under the current operating conditions and the rated energy demand of the energy storage device; The energy demand parameter is determined based on the actual energy demand and the rated energy demand.

4. The control method for a heat pump system as described in claim 3, characterized in that, The step of obtaining the actual energy demand of the energy storage device under the current operating conditions includes: Obtain the energy storage temperature of the energy storage device and the corresponding outdoor ambient temperature of the heat pump system; The actual energy demand is determined based on the energy storage temperature and the outdoor ambient temperature.

5. The control method for a heat pump system as described in claim 3, characterized in that, The steps for obtaining the rated energy demand include: Obtain the volume of the energy storage device used to store the energy storage material; The rated energy requirement is determined based on the volume.

6. The control method for the heat pump system as described in any one of claims 1 to 5, characterized in that, The step of controlling the operating frequency of the compressor based on the system pressure and the target pressure of the heat pump system includes: Determine the pressure difference between the target pressure and the system pressure; When the pressure difference is greater than the first threshold, the compressor is controlled to increase its operating frequency; When the pressure difference is less than or equal to the second threshold, the compressor is controlled to reduce its operating frequency. Wherein, the second threshold is less than or equal to the first threshold.

7. The control method for a heat pump system as described in any one of claims 1 to 5, characterized in that, Following the step of controlling the operating frequency of the compressor based on the system pressure and the target pressure of the heat pump system, the method further includes: The target duration is determined based on the deviation between the target pressure of the heat pump system and the system pressure, and the target duration is negatively correlated with the deviation. After the target time interval, return to the step of obtaining the system pressure of the heat pump system.

8. A heat pump system, characterized in that, The heat pump system includes a control device, a refrigerant main circuit and refrigerant branch circuits. The refrigerant main circuit includes an indoor heat exchanger and a compressor, and the refrigerant branch circuits include an energy storage device. The compressor is connected to the control device, which includes a memory, a processor, and a control program for the heat pump system stored in the memory and executable on the processor. When the control program for the heat pump system is executed by the processor, it implements the steps of the control method for the heat pump system as described in any one of claims 1 to 7.

9. A storage medium, characterized in that, The storage medium stores a control program for a heat pump system, which, when executed by a processor, implements the steps of the control method for a heat pump system as described in any one of claims 1 to 7.

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