Ground source heat pump system and control method thereof

Abstract

The application provides a ground source heat pump system and a control method thereof. Annual historical operation data of the ground source heat pump system are acquired, and the annual historical operation data include cooling season parameters and heating season parameters. A first predicted heat and a predicted heat discharge are calculated according to the cooling season parameters, wherein the sum of the first predicted heat and the predicted heat discharge is equal to a preset heat value. A second predicted heat is calculated according to the heating season parameters. The predicted heat discharge is adjusted so as to make the first predicted heat consistent with the second predicted heat. The technical scheme of the application collects the annual historical operation data of the ground source heat pump system, and combines meteorological characteristics to predict soil heat release and soil heat absorption. The first predicted heat and the second predicted heat of the prediction result are compared to realize accurate control of soil heat balance. When the prediction is inconsistent, the prediction result is adjusted and intervened in time to realize full use of soil constant temperature characteristics of a heat exchange region and improve operation efficiency of the ground source heat pump system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heating, ventilation and air conditioning technology, and particularly relates to a ground source heat pump system and a control method thereof. BACKGROUND

[0002] A heat pump is a device that can obtain low-grade heat from nature, such as air, water or soil, and output usable high-grade heat energy through electric power work. It can convert the consumed high-grade electric energy into 3 times or even more than 3 times of heat energy, and is a high-efficiency energy supply technology. The application of heat pump technology in the field of air conditioning can be divided into three categories: air source heat pump, water source heat pump and ground source heat pump.

[0003] A ground source heat pump utilizes the constant temperature characteristics of the soil at a depth of 5-10 m, and uses the constant temperature layer of the soil as a carrier for heat storage and cold storage. In summer, the heat is released to the underground soil through the circulating working medium (i.e., the soil acts as a cooling source), and in winter, the heat is absorbed from the underground soil (i.e., the soil acts as a low-temperature heat source). Due to good heat exchange conditions, the operating efficiency (i.e., COP) of the ground source heat pump can reach 3.5-4.5, which can save about 60% of electric energy compared to the air source heat pump. This is of great significance for reducing building operation carbon emissions and for air conditioning systems to participate in demand response as flexible loads.

[0004] Data shows that the fluctuation of underground soil temperature decreases with the increase of depth, and at a depth of 7 m, the annual fluctuation of soil temperature can be almost ignored, and it can be considered as a constant temperature state. In an air conditioning system with auxiliary heat dissipation or auxiliary heating, the operating efficiency of the system can be improved by optimizing energy management and fully utilizing the constant temperature characteristics of the soil layer in the heat exchange area, so as to achieve the goal of energy saving and carbon reduction.

[0005] In hot summer and warm winter regions and cool summer and cold winter regions, the heat discharged by the air conditioning system in summer is not equal to the heating heat required in winter, which requires that the heat balance of the soil in the heat exchange area be ensured during the operation of the ground source heat pump, i.e., the heat released to the underground soil in summer is equal to the heat absorbed from the underground soil in winter. This is crucial for the stable and efficient operation of the ground source heat pump, otherwise it will result in a decrease in the operating efficiency of the ground source heat pump, or even the failure of normal operation.

[0006] In the prior art, the common control method for soil heat balance is to control through the number of operating hours or through the outlet water temperature of the ground heat exchanger. This control method is relatively extensive and cannot meet the requirements of soil heat balance in the heat exchange area. Moreover, the cooperation strategy for cooling tower heat dissipation and soil heat dissipation is unreasonable, and the utilization of the constant temperature characteristics of the soil is also unreasonable, which cannot fully utilize the advantage of high operating efficiency of the ground source heat pump. SUMMARY

[0007] The main purpose of the present application is to provide a ground source heat pump system and a control method thereof, aiming at solving the technical problems in the prior art that the control mode by operating hours or by outlet water temperature of the ground heat exchanger is difficult to meet the requirement of soil heat balance in the heat exchange area, and the cooperation strategy of cooling tower heat dissipation and soil heat dissipation is unreasonable, the characteristics of soil constant temperature are not reasonably utilized, and the operation efficiency of the ground source heat pump cannot be fully utilized.

[0008] To achieve the above-mentioned purpose, the present application provides a ground source heat pump system control method, which comprises:

[0009] obtaining annual historical operation data of the ground source heat pump system, wherein the annual historical operation data comprises cooling season parameters and heating season parameters;

[0010] calculating a first predicted heat and a predicted heat discharge according to the cooling season parameters, wherein the sum of the first predicted heat and the predicted heat discharge is equal to a preset heat value;

[0011] calculating a second predicted heat according to the heating season parameters;

[0012] adjusting the predicted heat discharge so that the first predicted heat is consistent with the second predicted heat.

[0013] Optionally, the ground source heat pump system comprises a cooling tower and a condenser, and the step of adjusting the predicted heat discharge comprises:

[0014] obtaining a target time period in which the outdoor wet-bulb temperature is the lowest in the cooling season;

[0015] obtaining a first maximum heat discharge power of the condenser and a second maximum heat discharge power of the cooling tower in the target time period;

[0016] decomposing the predicted heat discharge according to the second maximum heat discharge power and the first maximum heat discharge power to obtain a cooling tower target heat discharge in the target time period;

[0017] discharging heat according to the cooling tower target heat discharge in the corresponding target time period.

[0018] Optionally, the step of decomposing the predicted heat discharge according to the second maximum heat discharge power and the first maximum heat discharge power to obtain a cooling tower target heat discharge in the target time period comprises:

[0019] judging whether the second maximum heat discharge power is greater than the first maximum heat discharge power;

[0020] decomposing the predicted heat discharge according to the judgment result to obtain a cooling tower target heat discharge in the target time period.

[0021] Optionally, the step of decomposing the predicted heat rejection according to the judgment result to obtain the cooling tower target heat rejection in the target time period comprises:

[0022] when the second maximum heat rejection power is greater than or equal to the first maximum heat rejection power, taking the first maximum heat rejection power as the cooling tower target heat rejection in the target time period;

[0023] when the second maximum heat rejection power is less than the first maximum heat rejection power, taking the second maximum heat rejection power as the cooling tower target heat rejection in the target time period.

[0024] Optionally, the ground source heat pump system comprises a ground heat exchanger and a compressor, and the steps of calculating the first predicted heat and the predicted heat rejection according to the cooling season parameter comprise:

[0025] obtaining the first flow rate, the first water inlet temperature and the first water outlet temperature of the ground heat exchanger in the cooling season according to the cooling season parameter;

[0026] calculating the first predicted heat according to the first flow rate, the first water inlet temperature and the first water outlet temperature;

[0027] obtaining the terminal cooling load in the cooling season and the operating power of the compressor according to the cooling season parameter;

[0028] calculating the predicted heat rejection according to the terminal cooling load, the operating power and the first predicted heat.

[0029] Optionally, the first flow rate q1, the first water inlet temperature T 11 , the first water outlet temperature T 12 and the first predicted heat Q1 satisfy the following relationship:

[0030]

[0031] wherein C is the specific heat capacity of water, t is the starting time of the cooling season, and n is the ending time of the cooling season.

[0032] Optionally, the terminal cooling load Q4, the operating power W1, the first predicted heat Q1 and the predicted heat rejection Q3 satisfy the following relationship:

[0033] Q4+W1=Q1+Q3.

[0034] Optionally, the step of calculating the second predicted heat according to the heating season parameter comprises:

[0035] acquire a second flow rate, a second inlet water temperature and a second outlet water temperature of the ground heat exchanger in the heating season according to the heating season parameter;

[0036] calculate the second predicted heat according to the second flow rate, the second inlet water temperature and the second outlet water temperature.

[0037] Optionally, the second flow rate q2, the first inlet water temperature T 21 , the first outlet water temperature T 22 and the first predicted heat Q2 satisfy the following relationship:

[0038]

[0039] Wherein, C is the specific heat capacity of water, t is the starting time of the heating season, and n is the ending time of the heating season.

[0040] In addition, to solve the above problems, the application also provides a ground source heat pump system, which comprises a compressor, an evaporator and a condenser which are in communication with each other, a cooling tower and a ground heat exchanger connected with the condenser, a memory, a processor and a ground source heat pump system control program stored in the memory and executable on the processor;

[0041] The processor is electrically connected with the memory, the compressor, the evaporator, the condenser, the cooling tower and the ground heat exchanger respectively;

[0042] The ground source heat pump system control program is executed by the processor to realize the steps of the ground source heat pump system control method as described above.

[0043] The technical scheme of the application collects the annual historical operation data of the ground source heat pump system, and predicts the heat release and absorption of the soil by combining with the meteorological characteristics, compares the first predicted heat and the second predicted heat of the prediction results, realizes the accurate control of the soil heat balance, and adjusts and intervenes in the prediction results in time when the prediction is inconsistent, so as to realize the full use of the constant temperature characteristics of the soil in the heat exchange area, and further improve the operation efficiency of the ground source heat pump system. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical scheme in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description only show some embodiments of the application, and those skilled in the art can obtain other drawings according to the structures shown in the drawings without creative labor.

[0045] Figure 1Flow chart for the first embodiment of the ground source heat pump system control method of the present application;

[0046] Figure 2 Flow chart for the second embodiment of the ground source heat pump system control method of the present application;

[0047] Figure 3 Flow chart for the third embodiment of the ground source heat pump system control method of the present application;

[0048] Figure 4 Flow chart for the fourth embodiment of the ground source heat pump system control method of the present application;

[0049] Figure 5 Flow chart for the fifth embodiment of the ground source heat pump system control method of the present application.

[0050] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0052] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0053] In addition, the description such as "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the technical features indicated or the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0054] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood broadly, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium, can be internal communication of two elements or interaction relationship between two elements, unless otherwise explicitly limited. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0055] In addition, the technical solutions among various embodiments of the present application can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the protection scope required by the present application.

[0056] The present application proposes a ground source heat pump system control method, please refer to Figure 1 , Figure 1 The flowchart of the first embodiment of the ground source heat pump system control method of the present application is shown in the figure, and the ground source heat pump system control method comprises the following steps:

[0057] Step S10: obtaining the annual historical operation data of the ground source heat pump system;

[0058] Step S20: calculating the first predicted heat and predicted heat rejection according to the cooling season parameters;

[0059] Step S30: calculating the second predicted heat according to the heating season parameters;

[0060] Step S40: adjusting the predicted heat rejection so that the first predicted heat and the second predicted heat are consistent.

[0061] The annual historical operation data of the previous years is obtained; classified according to different seasons, for example, the annual historical operation data between May 2022 and April 2023 is obtained, the parameters obtained from May 2022 to October 2022 are defined as cooling season parameters, that is, the operation data of summer; the parameters obtained from November 2022 to April 2023 are defined as heating season parameters, that is, the operation parameters of winter.

[0062] The time length of the annual historical operation data can be set to 1-3 years. The annual historical operation data should be obtained at least within one year.

[0063] In practical application, the ground source heat pump system operates in different modes in different seasons. For example, in hot summer, the ground source heat pump system absorbs heat through the evaporator to achieve the refrigeration effect. In the process of refrigeration, the heat discharged by the condenser can be partially discharged to the air through the cooling tower, and the other part can be released to the soil through the buried pipe heat exchanger. Correspondingly, in cold winter, the ground source heat pump system discharges heat through the condenser to achieve the heating effect. In the process of heating, the evaporator absorbs the heat stored in the soil for heating, thereby realizing heat circulation.

[0064] In the process of refrigeration and heating, the evaporator and the condenser can be replaced with each other, thereby realizing the refrigeration and heating effects.

[0065] In this embodiment, according to the meteorological data of different regions, summer and winter can be divided according to different months.

[0066] For example, according to the meteorological data of a certain place, May 2022-October 2022 is divided into summer, and November 2022-April 2023 is divided into winter. Then, the first predicted heat is calculated according to the cooling season parameters between May 2022 and October 2022; the second predicted heat is calculated according to the heating season parameters between November 2022 and April 2023.

[0067] The first predicted heat refers to the total heat released to the soil by the ground source heat pump system when refrigerating within May 2022-October 2022; the first predicted heat is taken as the predicted value of the total heat released to the soil by the heat pump system when refrigerating between May 2023 and October 2023.

[0068] The second predicted heat refers to the total heat absorbed from the soil by the ground source heat pump system when heating within November 2022-April 2023. The second predicted heat is taken as the predicted value of the total heat absorbed from the soil by the ground source heat pump system when heating between November 2023 and April 2024.

[0069] In addition, when the annual historical operation data within three years is collected, the total heat in each year is calculated according to the cooling season in different years, i.e., May 2020 to October 2020, May 2021 to October 2021, and May 2022 to October 2022, respectively, and the first predicted heat is the annual average of the total heat released into the soil by the ground source heat pump system during refrigeration in the three years; similarly, the heating season in different years is obtained according to the historical meteorological data, i.e., November 2020 to April 2021, November 2021 to April 2022, and November 2022 to April 2023, and the second predicted heat is the annual average of the three years.

[0070] The first predicted heat and the second predicted heat are compared, and when they are consistent, it means that the prediction is accurate; when the first predicted heat and the second predicted heat are significantly different, for example, the difference is greater than a preset value, it is considered that they are inconsistent. Therefore, the operation data of the ground source heat pump system in the next year (2023) needs to be debugged to make the final prediction result consistent.

[0071] In the present application, a rolling prediction method can be used to update the values of the first predicted heat and the second predicted heat in real time during the use of the ground source heat pump.

[0072] The technical scheme of the present application collects the annual historical operation data of the ground source heat pump system, and combines the historical meteorological data to predict the heat released by the soil and the heat absorbed by the soil. By comparing the first predicted heat and the second predicted heat of the prediction result, the accurate control of the soil heat balance is realized. When the prediction is inconsistent, the prediction result is adjusted in time, so as to realize the full use of the constant temperature characteristics of the soil in the heat exchange area, and further improve the operation efficiency of the ground source heat pump system.

[0073] Further, please refer to Figure 2 , Figure 2 is a flowchart of the second embodiment of the ground source heat pump system control method of the present application, and step S40 comprises:

[0074] Step S41: obtaining the priority of the outdoor wet-bulb temperature in each target time period in the cooling season;

[0075] Step S42: obtaining the first maximum heat rejection power of the condenser and the second maximum heat rejection power of the cooling tower in each target time period in the order of the priority;

[0076] Step S43: decomposing the predicted heat exhaust according to the second maximum heat exhaust power and the first maximum heat exhaust power to obtain a cooling tower target heat exhaust corresponding to the target time period;

[0077] Step S44: performing heat exhaust cooling tower target heat exhaust according to the cooling tower target heat exhaust in each corresponding target time period.

[0078] In the cooling season, the outdoor environment parameters between May and October are obtained, including, for example, the outdoor temperature, the relative humidity, etc., and the average outdoor wet-bulb temperature of each month is calculated according to the outdoor environment parameters. The months are sorted in order from low to high, and the heat is discharged as much as possible in the month with the lowest outdoor wet-bulb temperature. For example, the month with the lowest outdoor wet-bulb temperature in the cooling season (May to October) is obtained, and the heat is discharged as much as possible through the cooling tower in this month.

[0079] In actual application, since the cooling tower has a power upper limit, the second maximum heat exhaust power is the heat discharged by the cooling tower running at the maximum power in a month.

[0080] At the same time, the first maximum heat exhaust power is the heat that the condenser needs to discharge in a month due to different heat requirements of the work task in each month. For example, the work task is heavier in the month, and the refrigeration demand is higher, so the heat exhaust of the condenser is larger, and the first maximum heat exhaust power is larger. Conversely, the work task is lighter in the month, and the heat exhaust of the condenser is smaller, so the first maximum heat exhaust power is smaller.

[0081] Finally, the outdoor wet-bulb temperature, the first maximum heat exhaust power, and the second maximum heat exhaust power of the cooling tower are dynamically matched to discharge the heat as much as possible in the target time period.

[0082] For example, the outdoor wet-bulb temperature in May is the lowest in the cooling season, so the heat is discharged according to the maximum heat exhaust in the month; the month with the lowest outdoor wet-bulb temperature other than May is October, so the heat is also discharged according to the maximum heat exhaust in the month; and so on, until the total heat exhaust in the cooling season is discharged.

[0083] It should be noted that the target time period can be one month, two months, or three months, which can be adjusted according to the outdoor wet-bulb temperature. In order to further improve the flexibility of adjustment, the target time period can also be a specific number of days in a month, for example, the target time period can be May 1st or July 1st, etc., and the heat is reasonably discharged in the corresponding month to improve work efficiency.

[0084] Further, please refer to Figure 3 , Figure 3For the flowchart of the third embodiment of the ground source heat pump system control method of the present application, step S43 comprises:

[0085] Step S431: determining whether the second maximum heat rejection power is greater than the first maximum heat rejection power;

[0086] Step S432: decomposing the predicted heat rejection according to the determination result to obtain the cooling tower target heat rejection in the target time period.

[0087] In actual application, since the cooling tower has a power upper limit, i.e., the second maximum heat rejection power that can be achieved by operating the cooling tower at maximum power within a month.

[0088] At the same time, due to different heat requirements of work tasks every month, in months with heavy work tasks and high cooling demand, the heat to be discharged is large; in contrast, in months with light work tasks and low cooling demand, the heat to be discharged is small.

[0089] Specifically, step S432 comprises:

[0090] Step S4321: when the second maximum heat rejection power is greater than or equal to the first maximum heat rejection power, taking the first maximum heat rejection power as the cooling tower target heat rejection in the target time period;

[0091] Step S4322: when the second maximum heat rejection power is less than the first maximum heat rejection power, taking the second maximum heat rejection power as the cooling tower target heat rejection in the target time period.

[0092] By comparing the sizes of the first maximum heat rejection power and the second maximum heat rejection power. For example, the second maximum heat rejection power of the cooling tower in the target time period is converted to 100000 kilojoules, and the first maximum heat rejection power generated by the condenser due to work tasks in the target time period is 5000 kilojoules, so at most only 5000 kilojoules of the first maximum heat rejection power can be discharged in the target time period; when the second maximum heat rejection power of the cooling tower in the target time period is 100000 kilojoules, and the first maximum heat rejection power generated by work tasks in the target time period is 15000 kilojoules, at most only 100000 kilojoules of the second maximum heat rejection power can be discharged in the target time period.

[0093] In other time periods of the target time period in the cooling season, different heat rejections can be executed by the cooling tower according to the calculation, thereby improving the flexibility of the ground source heat pump system control method of the present application.

[0094] Further, the ground source heat pump system comprises a ground heat exchanger and a compressor, please refer to Figure 4 , Figure 4 The flowchart of the fourth embodiment of the ground source heat pump system control method of the present application is shown in Figure 20, and step S20 comprises:

[0095] Step S21: obtaining the first flow rate, the first inlet water temperature and the first outlet water temperature of the ground heat exchanger in the cooling season according to the cooling season parameters;

[0096] Step S22: calculating the first predicted heat according to the first flow rate, the first inlet water temperature and the first outlet water temperature;

[0097] Step S23: obtaining the terminal cooling load in the cooling season and the operating power of the compressor according to the cooling season parameters;

[0098] Step S24: calculating the predicted heat rejection according to the terminal cooling load, the operating power and the first predicted heat.

[0099] Temperature sensors with remote transmission function are installed at the inlet and outlet of the ground heat exchanger, and flow meters with remote transmission function are installed, so as to collect the inlet water temperature, outlet water temperature and flow rate of the ground heat exchanger.

[0100] The annual historical operation data within one year is taken as an example for illustration.

[0101] The collection frequency of the temperature sensor and the flow meter is set to 1 minute, and the data collected between May 2022 and October 2022 is taken as the cooling season parameters, and the average values of the temperature and flow rate in the cooling season parameters are calculated, so as to be taken as the first flow rate q1, the first inlet water temperature T 11 , and the first outlet water temperature T 12 , respectively.

[0102] The first predicted heat released to the soil can be calculated according to the following formula:

[0103] Formula 1: Wherein, C is the specific heat capacity of water, which is 4.18 kJ / (kg*℃); t is the starting time of the cooling season, i.e. 0:00 on May 1, 2022; n is the end time of the cooling season, i.e. 24:00 on October 31, 2022.

[0104] The predicted heat rejection is the heat rejected to the air through the cooling tower in the cooling season. According to the demand of different terminals, i.e. the work task demand, the terminal cooling load Q4 is determined, for example, the greater the terminal cooling load Q4 in the months with heavy work tasks. The operating power W1 of the compressor is recorded by an electric energy meter.

[0105] In the experimental environment, the sum of the terminal cold load and the operating power is equal to the first predicted heat and the predicted heat discharge Q3. Specifically, the following formula is used for calculation:

[0106] Formula 3: Q4+W1=Q1+Q3.

[0107] It should be noted that the operating power W1 is in degree, and the heat is in kilojoule. In the calculation process, unit conversion can be used to calculate the predicted heat discharge.

[0108] When the first predicted heat and the second predicted heat are inconsistent, the predicted value of the next year should be adjusted. According to formula 3, the sum of the first predicted heat and the predicted heat discharge is equal to the preset heat value. In the case that the terminal cold load Q4 and the operating power W1 are unchanged, adjusting the predicted heat discharge Q3 can indirectly adjust the size of the first predicted heat Q1.

[0109] Further, please refer to Figure 5 , Figure 5 is a flowchart of the fifth embodiment of the ground source heat pump system control method of the present application. Step S30 comprises:

[0110] Step S31: acquiring the second flow rate, the second inlet water temperature and the second outlet water temperature of the ground heat exchanger in the heating season according to the heating season parameters;

[0111] Step S32: calculating the second predicted heat according to the second flow rate, the second inlet water temperature and the second outlet water temperature.

[0112] The collection frequency of the temperature sensor and the flow meter is set to 1 time per minute. The data collected between November 2022 and April 2023 is acquired as the heating season parameters, and the average values of the temperature and the flow rate in the heating season parameters are calculated, so as to be respectively taken as the second flow rate q2, the first inlet water temperature T 21 , and the first outlet water temperature T 22 .

[0113] The second predicted heat absorbed from the soil can be calculated according to the following formula:

[0114] Formula 2: Wherein, C is the specific heat capacity of water, which is 4.18 kJ / (kg*℃); t is the starting time, i.e. November 1, 2022, 0:00; n is the end time, i.e. April 30, 2023, 24:00.

[0115] In addition, to solve the above problems, the application further provides a ground source heat pump system, which comprises a compressor, an evaporator and a condenser that are in communication with each other, a cooling tower and a ground heat exchanger connected with the condenser, a storage, a processor and a ground source heat pump system control program stored in the storage and executable on the processor; the ground source heat pump system control program is executed by the processor to realize the steps of the ground source heat pump system control method described above.

[0116] The annual historical operation data of previous years is obtained; the annual historical operation data between May 2022 and April 2023 is obtained, the parameters obtained between May 2022 and October 2022 are defined as cooling season parameters, i.e. summer operation data; and the parameters obtained between November 2022 and April 2023 are defined as heating season parameters, i.e. winter operation parameters.

[0117] The time length of the annual historical operation data can be set to 1-3 years. The annual historical operation data should be obtained at least within one year.

[0118] In actual application, the ground source heat pump system operates in different ways in different time seasons. For example, in hot summer, the ground source heat pump system absorbs heat through the evaporator to achieve refrigeration effect. In the refrigeration process, the heat discharged from the condenser can be partially discharged to the air through the cooling tower, and the other part can be released to the soil through the ground heat exchanger. Correspondingly, in cold winter, the ground source heat pump system discharges heat through the condenser to achieve heating effect. In the heating process, the evaporator absorbs the heat stored in the soil for heating, thereby realizing heat circulation.

[0119] In the process of refrigeration and heating, the evaporator and the condenser can be replaced with each other, thereby realizing refrigeration and heating effect.

[0120] In this embodiment, according to the meteorological data of different regions, summer and winter can be divided according to different months.

[0121] For example, according to the meteorological data of a certain place, May 2022-October 2022 is divided into summer, and November 2022-April 2023 is divided into winter. Then the first predicted heat is calculated according to the cooling season parameters between May 2022 and October 2022; and the second predicted heat is calculated according to the heating season parameters between November 2022 and April 2023.

[0122] The first predicted heat refers to the total heat released into the soil by the ground source heat pump system during cooling from May 2022 to October 2022; the first predicted heat is taken as the predicted value of the total heat released into the soil by the heat pump system during cooling from May 2023 to October 2023.

[0123] The second predicted heat refers to the total heat absorbed from the soil by the ground source heat pump system during cooling from November 2022 to April 2023; the second predicted heat is taken as the predicted value of the total heat absorbed from the soil by the ground source heat pump system during cooling from November 2023 to April 2024.

[0124] In addition, when the annual historical operation data within three years is collected, the total heat in each year is calculated according to the historical meteorological data of the cooling season in different years, i.e., May 2020 to October 2020, May 2021 to October 2021, and May 2022 to October 2022, respectively; the first predicted heat is the annual average of the total heat released into the soil by the ground source heat pump system during cooling in the three years; similarly, the total heat in each year is calculated according to the historical meteorological data of the heating season in different years, i.e., November 2020 to April 2021, November 2021 to April 2022, and November 2022 to April 2023, respectively; and the annual average of the three years is taken as the second predicted heat.

[0125] The first predicted heat and the second predicted heat are compared, and when they are consistent, it means that the prediction is accurate; when the first predicted heat and the second predicted heat are significantly different, for example, the difference is greater than a preset value, it is considered that they are inconsistent. Therefore, the operation data of the ground source heat pump system in the next year (2023) needs to be debugged to make the final prediction result consistent.

[0126] In the present application, a rolling prediction method can be used to update the values of the first predicted heat and the second predicted heat in real time during the use of the ground source heat pump.

[0127] The technical scheme of the present application collects the annual historical operation data of the ground source heat pump system, and combines the historical meteorological data to predict the heat released by the soil and the heat absorbed by the soil, and compares the first predicted heat and the second predicted heat of the prediction result to realize accurate control of the soil heat balance. When the prediction is inconsistent, the prediction result is adjusted in time to realize full use of the constant temperature characteristics of the soil in the heat exchange area, thereby improving the operation efficiency of the ground source heat pump system.

[0128] The above merely describes the preferred embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structural changes made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields, are included in the patent protection scope of the present application.

Claims

1. A ground source heat pump system control method characterized by, The ground source heat pump system control method comprises: obtaining annual historical operation data of a ground source heat pump system, wherein the annual historical operation data comprises cooling season parameters and heating season parameters; calculating a first predicted heat and a predicted heat discharge according to the cooling season parameters, wherein the sum of the first predicted heat and the predicted heat discharge is equal to a preset heat value; calculating a second predicted heat according to the heating season parameters; adjusting the predicted heat discharge so that the first predicted heat is consistent with the second predicted heat; the ground source heat pump system comprises a cooling tower and a condenser, and the step of adjusting the predicted heat discharge comprises: obtaining a priority of outdoor wet-bulb temperature in each target time period in the cooling season, wherein the priority is arranged from low to high according to the outdoor wet-bulb temperature, and the target time period corresponding to the lowest outdoor wet-bulb temperature has the highest priority; obtaining a first maximum heat discharge power of the condenser and a second maximum heat discharge power of the cooling tower in each target time period according to the priority; decomposing the predicted heat discharge according to the second maximum heat discharge power and the first maximum heat discharge power to obtain a cooling tower target heat discharge in the corresponding target time period; discharging heat according to the cooling tower target heat discharge in each corresponding target time period.

2. The ground source heat pump system control method according to claim 1, characterized by, The step of decomposing the predicted heat discharge according to the second maximum heat discharge power and the first maximum heat discharge power to obtain a cooling tower target heat discharge in the target time period comprises: determining whether the second maximum heat discharge power is greater than the first maximum heat discharge power; decomposing the predicted heat discharge according to the determination result to obtain the cooling tower target heat discharge in the target time period.

3. The ground source heat pump system control method according to claim 2, characterized by, The step of decomposing the predicted heat discharge according to the determination result to obtain the cooling tower target heat discharge in the target time period comprises: when the second maximum heat discharge power is greater than or equal to the first maximum heat discharge power, taking the first maximum heat discharge power as the cooling tower target heat discharge in the target time period; when the second maximum heat discharge power is less than the first maximum heat discharge power, taking the second maximum heat discharge power as the cooling tower target heat discharge in the target time period.

4. The ground source heat pump system control method according to claim 1, characterized by, The ground source heat pump system comprises a ground heat exchanger and a compressor, and the step of calculating a first predicted heat and a predicted heat discharge according to the cooling season parameters comprises: obtaining a first flow rate, a first inlet water temperature and a first outlet water temperature of the ground heat exchanger in the cooling season according to the cooling season parameters; calculating the first predicted heat according to the first flow rate, the first inlet water temperature and the first outlet water temperature; obtaining a terminal cooling load in the cooling season and an operating power of the compressor according to the cooling season parameters; calculating the predicted heat discharge according to the terminal cooling load, the operating power and the first predicted heat.

5. The ground source heat pump system control method according to claim 4, characterized by, The first flow rate q1, the first inlet water temperature T 11 , the first outlet water temperature T 12 , and the first predicted heat Q1 satisfy the following relationship: wherein C is the specific heat capacity of water, t is the starting time of the cooling season, and n is the end time of the cooling season.

6. The ground source heat pump system control method according to claim 4, characterized by, The terminal cooling load Q4, the operating power W1, the first predicted heat Q1 and the predicted heat discharge Q3 satisfy the following relationship: Q4 + W1 = Q1 + Q3.

7. The ground source heat pump system control method according to claim 4, characterized by, The step of calculating the second predicted heat according to the heating season parameter comprises: According to the heating season parameter, the second flow rate, the second inlet water temperature and the second outlet water temperature of the ground heat exchanger in the heating season are obtained; The second predicted heat is calculated according to the second flow rate, the second inlet water temperature and the second outlet water temperature.

8. The ground source heat pump system control method according to claim 7, characterized by, The second flow rate q2, the second inlet water temperature T 21 , the second outlet water temperature T 22 and the second predicted heat Q2 satisfy the following relationship: Wherein, C is the specific heat capacity of water, t is the starting time of the heating season, and n is the end time of the heating season.

9. A ground source heat pump system characterised in that, The ground source heat pump system comprises a compressor, an evaporator and a condenser which are mutually connected, a cooling tower and a ground heat exchanger which are connected with the condenser, a memory, a processor and a ground source heat pump system control program stored in the memory and capable of running on the processor; The processor is electrically connected with the memory, the compressor, the evaporator, the condenser, the cooling tower and the ground heat exchanger respectively; The ground source heat pump system control program is executed by the processor to realize the steps of the ground source heat pump system control method according to any one of claims 1 to 8.

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