Control method of heat pump system, heat pump system and storage medium

Abstract

The invention discloses a control method of a heat pump system, the heat pump system and a storage medium. The heat pump system comprises a refrigerant main path and a refrigerant branch path connected with the refrigerant main path, the refrigerant main path comprises an indoor heat exchanger and a compressor, the refrigerant branch path comprises an energy storage device, and the method comprises the steps that when the heat pump system starts a preset mode, energy demand parameters of the energy storage device are obtained; controlling the operation frequency of the compressor according to the energy demand parameters; when the operation of the heat pump system reaches a preset condition, the system pressure of the heat pump system is obtained; controlling the operation frequency of the compressor according to the system pressure; wherein in the preset mode, the indoor heat exchanger is not in a heat exchange state, and the energy storage device is in an energy storage state. The invention aims to improve the frequency regulation timeliness of the compressor while realizing quick energy storage so as to improve the energy storage effect.

Description

Technical Field

[0001] The present invention relates to the technical field of heat pumps, and in particular to a control method for a heat pump system, a heat pump system and a storage medium. Background Art

[0002] In addition to using energy to regulate the indoor environment, the heat pump system also has energy storage devices such as water tanks to provide the required energy for other needs. Among them, the heat pump system is generally equipped with a separate energy storage mode, in which the indoor air conditioning is stopped and the energy is stored in the energy storage device alone.

[0003] In the single energy storage mode, the heat pump system generally adjusts the operating frequency of the compressor according to the outdoor ambient temperature and the temperature of the energy storage device to achieve rapid energy storage. However, the temperature regulation has a lag, which can easily lead to untimely adjustment of the compressor frequency and affect the energy storage effect of the energy storage device. Summary of the invention

[0004] The main purpose of the present 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 to improve the energy storage effect.

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

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

[0007] controlling the operating frequency of the compressor according to the energy demand parameter;

[0008] When the operation of the heat pump system reaches a preset condition, obtaining the system pressure of the heat pump system;

[0009] controlling the operating frequency of the compressor according to the system pressure;

[0010] Wherein, in the preset mode, the indoor heat exchanger is not in a heat exchanging state, and the energy storage device is in an energy storage state.

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

[0012] Correcting the energy demand parameter according to the target correction value to obtain the initial frequency of the compressor;

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

[0014] Wherein, the target correction value is determined according to the exhaust parameter of the compressor.

[0015] Optionally, the step of obtaining the energy requirement parameter of the energy storage device includes:

[0016] Obtaining an actual energy requirement value of the energy storage device under current working conditions and a rated energy requirement value of the energy storage device;

[0017] The energy demand parameter is determined according to the actual energy demand value and the rated energy demand value.

[0018] Optionally, the step of obtaining the actual energy requirement value of the energy storage device under the current working condition includes:

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

[0020] The actual energy requirement value is determined according to the energy storage temperature and the outdoor ambient temperature.

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

[0022] Obtaining the volume of the energy storage device for storing energy storage material;

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

[0024] Optionally, the step of controlling the operating frequency of the compressor according to the system pressure comprises:

[0025] controlling the operating frequency of the compressor according to the system pressure and the target pressure of the heat pump system;

[0026] Wherein, the target pressure is determined according to the energy storage temperature of the energy storage device.

[0027] Optionally, the target pressure is defined as Tm and the energy storage temperature is defined as Tw, and 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 according to the system pressure and the target pressure of the heat pump system includes:

[0030] determining a pressure difference between the target pressure and the system pressure;

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

[0032] When the pressure difference is less than or equal to a second threshold, controlling the compressor to reduce the operating frequency;

[0033] 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 comprises:

[0035] Determining a target duration according to a deviation between a target pressure of the heat pump system and the system pressure, wherein the target duration is negatively correlated with the deviation;

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

[0037] In addition, in order to achieve the above-mentioned purpose, the present application also proposes a heat pump system, the heat pump system includes a control device, a refrigerant main circuit and a refrigerant branch circuit, 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, the steps of the control method for the heat pump system as described in any one of the above items are implemented.

[0039] In addition, in order to achieve the above-mentioned purpose, the present application also proposes a storage medium, on which a control program of a heat pump system is stored. When the control program of the heat pump system is executed by a processor, the steps of the control method of the heat pump system as described in any of the above items are implemented.

[0040] A control method for a heat pump system proposed in the present invention is based on a heat pump system including a refrigerant main circuit and a refrigerant branch circuit, wherein an energy storage device is arranged in the refrigerant branch circuit. After the heat pump system starts a preset mode, the method no longer adjusts the operating frequency of the compressor in a fixed manner according to the outdoor ambient temperature and the temperature of the energy storage device. First, 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 operation of the heat pump system reaches a preset condition, 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, the operating frequency of the compressor is controlled according to the system pressure, which can achieve rapid energy storage while improving the timeliness of the compressor frequency adjustment to improve the energy storage effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of the refrigerant flow path structure in an embodiment of the heat pump system of the present invention;

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

[0043] Figure 3 A schematic flow chart of an embodiment of a control method for a heat pump system of the present invention;

[0044] Figure 4 A schematic flow chart of another embodiment of a control method for a heat pump system of the present invention;

[0045] Figure 5 A schematic flow chart of another embodiment of a control method for a heat pump system of the present invention;

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

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

[0048] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0049] An embodiment of the present invention provides a heat pump system.

[0050] In the embodiment of the present invention, refer to Figure 1 and Figure 2 The heat pump system includes a control device 100, a refrigerant main circuit and a refrigerant branch circuit 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 component 5, and the refrigerant branch circuit includes an energy storage device 7 and a first control valve 8. The indoor unit, the reversing component 5, the compressor 1, the throttling device 4 and the first control valve 8 are all connected to the control device 100. The throttling device 4 and the first control valve 8 can both be electronic expansion valves.

[0051] In this embodiment, the energy storage device 7 includes a water tank (e.g., a water heater), and an external water-using device can be connected to the water tank to utilize the water with 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 an 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 provided with a flow direction regulating member, the pipeline between the indoor unit and the outdoor heat exchanger 3 is connected to the second end of the refrigerant branch, the return air 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 member, and the refrigerant branch is switched between being connected to the return air port of the compressor 1 and being connected to the exhaust port of the compressor 1 through the flow direction regulating member. The refrigerant branch is connected to the exhaust port of the compressor 1 through one end of the refrigerant branch.

[0054] In this embodiment, the number of indoor units is more than one, and more than one indoor units can be connected in parallel. In other embodiments, the number of indoor units can also be one.

[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 the control device 100, and the control device 100 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, the throttling device 4 and the outdoor heat exchanger 3 are connected in sequence, and the pipeline between the throttling device 4 and the indoor unit is connected to one end of the refrigerant branch. The indoor unit, the outdoor heat exchanger 3, the exhaust port of the compressor 1 and the return air port of the compressor 1 are all connected to the reversing component 5. The reversing component 5 can be used to switch the connection state between the indoor unit and the outdoor heat exchanger 3 and the exhaust port of the compressor 1 and the return air port of the 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 air 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 air 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 air 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 air 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 air 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 air 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), and the reversing assembly 5 (switching valve) may be used to switch the connection state between the energy storage device 7 and the exhaust port of the compressor 1 and the return port of the compressor 1. The switching valve may 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 exhaust port of the compressor 1 is connected to the energy storage device 7.

[0061] Through the regulation of the first reversing valve 51, the second reversing valve 52, the first control valve 8 and the second control valve 22, the operation 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 at the first valve position, the second reversing valve 52 operates at the fourth valve position, the second control valve 22 is closed, the first control valve 8 is opened, the refrigerant branch is connected to the exhaust port of the compressor 1 (when the reversing component 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, and the heat of the refrigerant flowing into the refrigerant branch is stored in the energy storage device 7 when flowing through the energy storage device 7, and the refrigerant flowing out of the refrigerant branch flows through the throttling device 4 and the outdoor heat exchanger 3 in turn and then flows back to the compressor 1. In the first mode, the indoor heat exchanger 21 stops heat exchange, the outdoor heat exchanger 3 is in an evaporating state, the energy storage device 7 is in a condensing state, and 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 separately.

[0063] In the second mode, the first reversing valve 51 operates at the first valve position, the second reversing valve 52 operates at the third valve position, the first control valve 8 is opened, and the second control valve 22 is opened, and the refrigerant branch is connected to the exhaust port of the compressor 1 (when the reversing component 5 includes a switching valve, the switching valve is in the second switching state), a part of the refrigerant discharged from the compressor 1 flows through the outdoor heat exchanger 3 and the throttling device 4 in sequence, and another part of the refrigerant discharged from the compressor 1 flows into the refrigerant branch, and the heat of the refrigerant flowing into the refrigerant branch is stored in the energy storage device 7 when flowing through the energy storage device 7, and 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 and then flows back to the compressor 1. In the second mode, the indoor heat exchanger 21 is in an evaporating state, and the outdoor heat exchanger 3 is in a condensing state. In the second mode, when the indoor space regulated by the indoor unit has a heat exchange demand, 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; in the second mode, when the indoor space regulated by the indoor unit does not have a heat exchange demand, 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 the environment can be stored in the energy storage device 7. In the second mode, the indoor environment can be cooled while the energy storage device 7 stores heat or the compressor 1 oil 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 at the first valve position, the second reversing valve 52 operates at the fourth valve position, the first control valve 8 is opened, and the second control valve 22 operates in throttling mode. 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), and 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 when flowing through the energy storage device 7. A part of the refrigerant flowing out of the refrigerant branch flows through the throttling device 4 and the outdoor heat exchanger 3 in sequence and then flows back to the compressor 1. Another part of the refrigerant flowing out of the refrigerant branch flows through the second control valve 22 and the indoor heat exchanger 21 in sequence and then flows back to the compressor 1. In the third mode, the indoor heat exchanger 21 and the outdoor heat exchanger 3 are both in an evaporating state. In the third mode, when the indoor space regulated by the indoor unit has a heat exchange demand, 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; in the third mode, when the indoor space regulated by the indoor unit does not have a heat exchange demand, 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 environment 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 at the first valve position, the second reversing valve 52 operates at the third valve position, the first control valve 8 is closed, and the second control valve 22 is opened. The refrigerant discharged from the compressor 1 flows through the outdoor heat exchanger 3, the throttling device 4, the second control valve 22, and the indoor heat exchanger 21 in sequence and then flows back 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. In the fourth mode, when the indoor space regulated by the indoor unit has a heat exchange demand, 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; in the fourth mode, when the indoor space regulated by the indoor unit does not have a heat exchange demand, 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, and the exhaust port of the compressor 1, the return air port of the compressor 1, the indoor heat exchanger 21 and the outdoor heat exchanger 3 are respectively connected to different valve ports of the third four-way valve.

[0067] Further, see Figure 1 to Figure 2 The heat pump system further includes a pressure sensor 01 , which can be disposed 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] Further, see Figure 2 The heat pump system further includes a temperature detection module 02, which is connected to the control device 100. The temperature detection module 02 can be arranged inside the energy storage device 7 to detect the energy storage temperature of the energy storage device 7.

[0069] Further, see Figure 2 The heat pump system further includes an environment detection module 03, which is connected to the control device 100. The environment detection module 03 can be arranged in an outdoor environment to detect the outdoor environment temperature.

[0070] In the embodiment of the present invention, refer to Figure 2 The control device of the heat pump system includes: a processor 1001, such as a CPU, a memory 1002, and a timer 1003. Among them, these components are connected and communicated through a communication bus. The memory 1002 can be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. 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 in the figure does not constitute a limitation of the device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0072] like Figure 2 As shown, the memory 1002 as a computer storage medium may include a control program for the 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 step operations of the control method of the heat pump system in the following embodiment.

[0074] An embodiment of the present invention further provides a control method for a heat pump system, which is applied to the above-mentioned heat pump system.

[0075] Reference Figure 3 , an embodiment of a control method of a heat pump system of the present application is proposed. In this embodiment, the control method of the heat pump system includes:

[0076] Step S10, when the heat pump system starts a preset mode, obtaining energy demand parameters of the energy storage device; wherein, in the preset mode, the indoor heat exchanger is not in a heat exchange state, and the energy storage device is in an energy storage state;

[0077] In this embodiment, the exhaust port of the compressor is connected to one end of the refrigerant branch, and the preset mode is the first mode mentioned above, that is, the separate heat storage mode. In other embodiments, the return air port of the compressor is connected to one end of the refrigerant branch, and the preset mode is also the separate cold storage mode.

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

[0079] The energy demand parameter may be determined based on detection data inside the energy storage device and / or detection data of the environment where the heat pump system is located.

[0080] After the heat pump system starts the preset mode, when the heat pump system does not meet the preset conditions, the energy demand parameters can be obtained at intervals of a first time, and the operating frequency of the compressor can be controlled according to the energy demand parameters until the heat pump system operates to meet the preset conditions.

[0081] Step S20, controlling the operating frequency of the compressor according to the energy demand parameter;

[0082] In an implementation of this embodiment, a target frequency at which the compressor needs to operate is determined according to energy demand parameters, and the compressor is controlled to operate at the target frequency.

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

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

[0085] Step S30, when the operation of the heat pump system reaches a preset condition, obtaining the system pressure of the heat pump system;

[0086] The preset conditions may represent the operating parameters of the heat pump system itself and / or the environmental state parameters of the environment where the heat pump system is located when the preset mode reaches a stable operating state after being started.

[0087] In this embodiment, the preset condition includes that the running time after the preset mode is started is greater than or equal to the preset time. In other embodiments, the preset condition may also include that the temperature change value of the energy storage device is greater than or equal to the preset change value.

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

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

[0090] In an implementation of this embodiment, the target frequency at which the compressor needs to operate is determined according to the system pressure, and the compressor is controlled to operate at the target frequency.

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

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

[0093] Here, after the preset mode is started, when the operation of the heat pump system does not reach the preset conditions, the heat pump system 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 large. At this time, the frequency of the compressor is adjusted according to the energy demand, which is beneficial to quickly store energy while improving the operating stability of the heat pump system; when the operation of the heat pump system reaches the preset conditions, the heat pump system is in the normal operating stage of the preset mode. At this time, the operation of the heat pump system reaches a stable state, and the energy demand of the energy demand device decreases. At this time, the frequency of the compressor is adjusted according to the system pressure, which is beneficial to improve the timeliness and accuracy of the adjustment of the compressor operating frequency, thereby ensuring that the energy storage device can accurately and quickly reach the required storage capacity and improve the energy storage effect.

[0094] A control method for a heat pump system proposed in an embodiment of the present invention no longer regulates the operating frequency of the compressor in a fixed manner according to the outdoor ambient temperature and the temperature of an energy storage device after the heat pump system starts a preset mode. First, the operating frequency of the compressor is controlled based on the energy demand of the energy storage device in the initial stage. At this time, the energy demand of the energy storage device is relatively large, and regulating the frequency according to the energy demand is conducive to achieving rapid energy storage. After the operation of the heat pump system reaches a preset condition, 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, the operating frequency of the compressor is controlled according to the system pressure, which can achieve rapid energy storage while improving the timeliness of the compressor frequency adjustment to improve the energy storage effect.

[0095] Further, based on the above embodiment, another embodiment of the control method of the heat pump system of the present application is proposed. In this embodiment, referring to Figure 4 , the step S20 comprises:

[0096] Step S21, correcting 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 parameter of the compressor;

[0097] The exhaust parameters include exhaust pressure and / or exhaust temperature, etc. The exhaust parameters can be specifically obtained by detection by a detection module disposed on the exhaust side of the compressor or calculated based on detection data of the detection module, etc.

[0098] The exhaust parameter may be the current exhaust parameter of the compressor, or may be a parameter determined based on a plurality of exhaust characteristic parameters of the compressor detected after the preset mode is started.

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

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

[0102] Step S22, controlling the compressor to operate at the initial frequency.

[0103] In this embodiment, in the initial operation stage of the preset mode, the energy requirement parameter is corrected according to the target correction value determined by the exhaust parameter of the compressor to obtain the operating frequency of the compressor in this stage, which is beneficial to quickly store energy while improving the operating reliability of the compressor.

[0104] Further, based on any of the above embodiments, another embodiment of the control method of the heat pump system of the present application is proposed. Figure 5 , the step of obtaining the energy requirement parameters of the energy storage device comprises:

[0105] Step S11, obtaining the actual energy requirement value of the energy storage device under the current working condition and the rated energy requirement value of the energy storage device;

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

[0107] The rated energy demand value is an 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: determining the energy requirement parameter according to the actual energy requirement value and the rated energy requirement value.

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

[0110] In this embodiment, the energy demand parameters of the energy storage device are determined in combination with the actual energy demand value and the rated energy demand value, which is beneficial to ensure that the determined energy demand parameters can accurately reflect the capacity requirements of the energy storage device in the initial stage, thereby facilitating further improving the accuracy of the compressor operating frequency adjustment, thereby further improving the energy storage efficiency in the initial stage of the preset mode.

[0111] In other embodiments, one of the actual energy demand value and the rated energy demand value may be used as the energy demand parameter.

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

[0113] The energy storage temperature is detected by the above-mentioned temperature sensor. The outdoor environment temperature is detected by the above-mentioned environment detection module.

[0114] Different energy storage temperatures and different outdoor ambient temperatures correspond to different actual energy demand values. The actual energy demand value is negatively correlated with the outdoor ambient temperature, and the actual energy demand value is negatively correlated with the energy storage temperature.

[0115] Specifically, a correspondence between the energy storage temperature, the outdoor ambient temperature and the actual energy requirement value can be established in advance. The correspondence may include a calculation formula, a mapping relationship, etc. Based on the correspondence, the actual energy requirement value corresponding to the current energy storage temperature and the outdoor ambient temperature can be determined.

[0116] Furthermore, more than one correspondence relationship between the energy storage temperature, the outdoor ambient temperature and the actual energy demand value can be pre-set, and the target correspondence relationship can be determined in more than one correspondence relationship 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, and the actual energy demand value corresponding to the current energy storage temperature and the outdoor ambient temperature is determined based on the target correspondence relationship.

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

[0118]

[0119]

[0120] Table 1

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

[0122] In this embodiment, the operating conditions of the preset mode can be accurately reflected by combining the outdoor ambient temperature and the energy storage temperature. Therefore, the actual energy demand value is determined according to the outdoor ambient temperature and the energy storage temperature, which is beneficial 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 facilitating further improving the accuracy of the compressor frequency operation control and improving the energy storage efficiency of the energy storage device.

[0123] In other embodiments, the actual energy requirement value may also be determined based on one of the outdoor ambient temperature and the energy storage temperature, or based on other parameters other than the outdoor ambient temperature and the energy storage temperature. The other parameters here 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 surface temperature and the outer surface temperature of the energy storage device and / or the temperature difference change rate between the inner surface temperature and the outer surface temperature of the energy storage device, and / or the temperature difference change rate between the inner surface temperature and the outer surface temperature of the energy storage device, and the like.

[0124] Furthermore, in this embodiment, the volume of the energy storage device for storing energy storage material is obtained, and the rated energy requirement is determined according to the volume. The volume is positively correlated with the rated energy requirement.

[0125] For example, the volume and rated energy demand values ​​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 requirement is determined according to the volume of the energy storage device, which is conducive to accurately reflecting the energy requirement required by the energy storage device's own properties during the energy storage process, thereby facilitating further improving the accuracy of the compressor frequency operation control and improving the energy storage efficiency of the energy storage device.

[0129] In other embodiments, the rated energy requirement value here may also be determined according to the shell thickness and material type of the energy storage device.

[0130] Further, based on any of the above embodiments, another embodiment of the control method of the heat pump system of the present application is proposed. In this embodiment, referring to Figure 6 , step S40 comprises:

[0131] Step S41, controlling 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 relationship or quantitative relationship (such as ratio or difference, etc.) between the system pressure and the target pressure, determine the frequency adjustment value of the compressor based on the magnitude relationship or quantitative relationship, adjust the operating frequency of the compressor according to the frequency adjustment value to obtain the target frequency of the compressor, 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 is positively correlated with the target pressure. A correspondence between the energy storage temperature and the target pressure is established in advance, and the correspondence may include a quantitative relationship, a mapping relationship, etc. Based on the 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 is defined as Tw, then 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 range of a is [0.001, 0.003], the value range of b is [0.5, 0.8], and the value range of c is [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 of target pressure and energy storage temperature may be pre-established, and the target pressure may be obtained by querying the mapping table based on the energy storage temperature.

[0136] In this embodiment, the target pressure and system pressure determined according to the energy storage temperature are used to regulate the operating frequency of the compressor, which is conducive to further improving the accuracy of the target pressure, and ensuring that when the operating frequency of the compressor is regulated based on the target pressure and the system pressure, the timeliness and accuracy of the compressor operating frequency regulation can be effectively improved to ensure that the output capacity of the compressor can be accurately matched with the energy storage demand of the energy storage device, thereby further improving the energy storage effect. Among them, when the target pressure and the energy storage temperature meet the above-mentioned quantitative relationship, it is conducive to further improving the accuracy of the target pressure to improve the energy storage effect. Furthermore, when a, b, and c are set according to the above parameter ranges, as the energy storage temperature increases, the increase in the target pressure corresponding to the preset amplitude of the energy storage temperature change tends to decrease, that is, when the energy storage temperature is low, the increase in the target pressure is large when the energy storage temperature increases by the preset amplitude, and when the energy storage temperature is high, the increase in the target pressure is small when the energy storage temperature increases by the preset amplitude. Based on this, it is beneficial to ensure that the system high pressure can be quickly 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 smoothly increased, which is beneficial to the rapid heat storage efficiency while further improving the operating stability of the heat pump system.

[0137] Furthermore, in this embodiment, the step of controlling the operating frequency of the compressor according to 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 the operating frequency; when the pressure difference is less than or equal to a second threshold, controlling the compressor to reduce the operating frequency; wherein the second threshold is less than or equal to the first threshold.

[0138] In this embodiment, the second threshold is smaller 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, and 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 frequency adjustment value of the compressor can be a pre-set fixed value or a value determined according to the actual operating state of the heat pump system. For example, the frequency adjustment value here can be determined based on the opening of the above-mentioned 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, etc., wherein the refrigerant heat dissipation module is used to dissipate heat from heat-generating components. The frequency adjustment value determined based on this is conducive to further improving the accuracy of the compressor operating frequency adjustment, thereby improving the energy storage effect while preventing condensation on the cooling module.

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

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

[0143] Step S50, determining a target duration according to a deviation between a 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 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] It can be seen from Table 3 that the positive and negative values ​​of the pressure difference can represent the size relationship between the target pressure and the system pressure. When the target pressure is greater than the system pressure or the target pressure is less than the preset pressure, the larger the deviation, the smaller the target time, and the smaller the deviation, the larger the target time.

[0148] Step S60, after the target time period, returning to the step of obtaining the system pressure of the heat pump system.

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

[0150] In addition, an embodiment of the present invention further proposes a storage medium, on which a control program of a heat pump system is stored. When the control program of the heat pump system is executed by a processor, the relevant steps of any embodiment of the control method of the heat pump system are implemented.

[0151] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0152] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0153] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, including a number of instructions for a terminal device (which can be a mobile phone, computer, server, heat pump system, or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0154] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A control method for a heat pump system, characterized in that: The heat pump system comprises a refrigerant main circuit and a refrigerant branch circuit connected to the refrigerant main circuit, the refrigerant main circuit comprises an indoor heat exchanger and a compressor, the refrigerant branch circuit comprises an energy storage device, and the control method of the heat pump system comprises the following steps: When the heat pump system starts a preset mode, obtaining energy demand parameters of the energy storage device; controlling the operating frequency of the compressor according to the energy demand parameter; When the operation of the heat pump system reaches a preset condition, obtaining the system pressure of the heat pump system; controlling the operating frequency of the compressor according to the system pressure; Wherein, in the preset mode, the indoor heat exchanger is not in a heat exchanging state, and the energy storage device is in an energy storage state.

2. The control method of the heat pump system according to claim 1, characterized in that: The step of controlling the operating frequency of the compressor according to the energy demand parameter comprises: Correcting the energy demand parameter according to the target correction value to obtain the initial frequency of the compressor; controlling the compressor to operate at the initial frequency; Wherein, the target correction value is determined according to the exhaust parameter of the compressor.

3. The control method of the heat pump system according to claim 1, characterized in that: The step of obtaining the energy requirement parameter of the energy storage device comprises: Obtaining an actual energy requirement value of the energy storage device under current working conditions and a rated energy requirement value of the energy storage device; The energy demand parameter is determined according to the actual energy demand value and the rated energy demand value.

4. The control method of the heat pump system according to claim 3, characterized in that: The step of obtaining the actual energy demand value of the energy storage device under the current working condition comprises: Acquire the energy storage temperature of the energy storage device and the outdoor ambient temperature corresponding to the heat pump system; The actual energy requirement value is determined according to the energy storage temperature and the outdoor ambient temperature.

5. The control method of the heat pump system according to claim 3, characterized in that: The steps of obtaining the rated energy demand value include: Obtaining the volume of the energy storage device for storing energy storage material; The rated energy demand is determined based on the volume.

6. The control method of the heat pump system according to any one of claims 1 to 5, characterized in that: The step of controlling the operating frequency of the compressor according to the system pressure comprises: controlling 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.

7. The control method of the heat pump system according to claim 6, characterized in that: Define the target pressure as Tm and the energy storage temperature as Tw, then 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.

8. The control method of the heat pump system according to claim 6, characterized in that: The step of controlling the operating frequency of the compressor according to the system pressure and the target pressure of the heat pump system comprises: determining a 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 the operating frequency; When the pressure difference is less than or equal to a second threshold, controlling the compressor to reduce the operating frequency; The second threshold is less than or equal to the first threshold.

9. The control method of the heat pump system according to claim 6, characterized in that: After the step of controlling the operating frequency of the compressor according to the system pressure, the method further includes: Determining a target duration according to a deviation between a target pressure of the heat pump system and the system pressure, wherein the target duration is negatively correlated with the deviation; After the target time period, return to the step of obtaining the system pressure of the heat pump system.

10. A heat pump system, characterized in that: The heat pump system comprises a control device, a refrigerant main circuit and a refrigerant branch circuit, the refrigerant main circuit comprises an indoor heat exchanger and a compressor, and the refrigerant branch circuit comprises 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, wherein the control program for the heat pump system, when executed by the processor, implements the steps of the control method for the heat pump system as described in any one of claims 1 to 9.

11. A storage medium, characterized in that: The storage medium stores a control program of the heat pump system, and when the control program of the heat pump system is executed by the processor, the steps of the control method of the heat pump system according to any one of claims 1 to 9 are implemented.

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