Geothermal energy supply heat balance control device and method

Abstract

The invention belongs to the technical field of ground source heat pump control, and discloses a geothermal energy supply heat balance control device and method.The method comprises the steps that collected local annual climate data, building energy consumption data and soil thermal characteristic data are processed and analyzed, and the annual cooling and heating load demand of a building is predicted; based on the soil thermal characteristic data, analyzing the soil temperature change when the ground source heat pump operates in winter and summer, and predicting the risk of soil thermal imbalance; based on the annual cooling and heating load demand and the soil heat imbalance risk, an annual operation plan of the ground source heat pump is made, heat taking and releasing balance in winter and summer is ensured, operation parameters of the ground source heat pump system are adjusted in real time, and intelligent control over heat taking and releasing balance is achieved. The energy efficiency and the stability of the system are improved, the operation cost and the environmental influence are reduced, and powerful support is provided for further popularization and application of the ground source heat pump technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of geothermal heat pump control, and relates to a geothermal energy supply heat balance control device and method. Background Art

[0002] The ground source heat pump system is a renewable energy utilization technology that utilizes the nearly infinite low-enthalpy thermal energy in the shallow layer of the earth's surface. It extracts and releases heat energy through geothermal heat exchangers, and diffuses the heat source and heat sink to the surrounding surface through the heat pump unit. However, due to the difference between the ground source heat pump releasing heat to the soil in summer and absorbing heat from the soil in winter, the soil temperature often changes continuously, affecting the long-term stable operation of the heat pump system. In the prior art, there are some solutions to the thermal balance problem of ground source heat pumps, such as adjusting the depth and length of buried pipes, installing auxiliary cold and heat source equipment, etc. However, most of these solutions lack systematic consideration of load changes throughout the year and fail to fundamentally solve the thermal balance problem. Summary of the invention

[0003] The purpose of the present invention is to solve the problem in the prior art that it is impossible to systematically consider the annual load changes from a year-round perspective, and to provide a geothermal energy supply heat balance control device and method.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A geothermal energy supply heat balance control device, comprising: a geothermal heat pump unit, a geothermal cooling tower, a cooling water pump on the cooling tower side, a geothermal side cooling water pump and an underground pipe;

[0006] The water outlet of the geothermal heat pump unit is connected to the water inlet of the geothermal cooling tower and the water inlet of the buried pipe respectively; the water outlet of the geothermal cooling tower is connected to the cooling water pump on the cooling tower side; the cooling water pump on the cooling tower side is connected to the water inlet of the geothermal heat pump unit; the water outlet of the buried pipe is connected to the cooling water pump on the geothermal side; the cooling water pump on the geothermal side is connected to the water inlet of the geothermal heat pump unit.

[0007] A further improvement of the present invention is:

[0008] Furthermore, a first ground source heat pump condensate switching electric valve is arranged between the water outlet of the ground source heat pump unit and the ground source cooling tower; a third ground source heat pump condensate switching electric valve is arranged between the cooling water pump on the cooling tower side and the water inlet of the ground source heat pump unit; a fourth ground source heat pump condensate switching electric valve and a flow meter are arranged between the ground source side cooling water pump and the water inlet of the ground source heat pump unit; and a second ground source heat pump condensate switching electric valve is arranged between the buried pipe and the ground source heat pump unit.

[0009] Furthermore, a ground source field temperature monitoring device is provided near the buried pipe to monitor the soil temperature at different depths near the buried pipe.

[0010] Furthermore, the geothermal heat pump unit, the geothermal cooling tower, the cooling water pump on the cooling tower side, the first geothermal heat pump condensate water switching electric valve and the third geothermal heat pump condensate water switching electric valve constitute a first cooling water circulation loop; the geothermal heat pump unit, the buried pipe, the geothermal side cooling water pump, the second geothermal heat pump condensate water switching electric valve and the fourth geothermal heat pump condensate water switching electric valve constitute a second cooling water circulation loop.

[0011] A geothermal energy supply heat balance control method, comprising:

[0012] S101, collects local annual climate data, building energy consumption data, and soil thermal characteristics data;

[0013] S102, processing and analyzing the collected data to predict the cooling and heating load demand of the building throughout the year;

[0014] S103, based on the collected soil thermal characteristic data, analyze the soil temperature changes when the ground source heat pump unit is running in winter and summer, and predict the risk of soil thermal imbalance;

[0015] S104, based on the annual cooling and heating load demand and the risk of soil thermal imbalance, formulate a year-round operation plan for the ground source heat pump unit to achieve intelligent control of heat extraction and release balance.

[0016] Furthermore, the local climate data throughout the year include: temperature and humidity of the dry-bulb thermometer, wind speed, wind direction, total radiation, direct radiation and scattered radiation; building energy consumption data include: building structure, wall material, size, orientation, building use function, personnel density and equipment configuration; soil thermal properties data include soil heat capacity, thermal conductivity and thermal diffusivity.

[0017] Furthermore, based on the collected building energy consumption data, parameters such as the building envelope structure are set in the energy consumption simulation software TRNSYS, and the air-conditioning system, lighting system and energy-consuming equipment are added to establish a model corresponding to the building; then the collected local meteorological data are input into TRNSYS and used as the simulated external conditions to run the simulation and obtain the building's cooling and heating loads throughout the year.

[0018] The ground-source heat pump unit takes heat from the soil and releases heat, taking heat for heating in winter and discharging excess heat in the building into the soil in summer. Based on the soil thermal characteristic data and the calculation results of the cooling and heating loads throughout the year, combined with the need to take and release heat from the soil, the soil temperature change is evaluated and calculated. The data collected by the ground source field temperature monitoring device is collected and analyzed, the soil temperature change is observed, and compared with the historical soil temperature data and the results of the evaluation calculation to verify the effectiveness of the control method.

[0019] Furthermore, in winter, the second ground source heat pump condensate switching electric valve and the fourth ground source heat pump condensate switching electric valve are opened; the first ground source heat pump condensate switching electric valve and the third ground source heat pump condensate switching electric valve are closed; the water of the ground source heat pump unit takes heat from the soil through the buried pipe, and after heating, it returns to the ground source heat pump unit through the ground source side cooling water pump, releases the heat to the supply building, and the ground source field temperature monitoring device monitors the temperature of the soil at different depths near the buried pipe. At the same time, the flow monitoring data of the flow meter and the temperature difference between the supply and return water of the ground source heat pump unit are used to calculate the heat obtained from the soil at each time period in winter; in summer, the ground source heat pump unit continues to work, and the ground source field temperature monitoring device continues to monitor the temperature of the soil at different depths near the buried pipe. At the same time, the heat released by the ground source heat pump unit to the soil in various periods in summer is calculated based on the flow monitoring data of the flow meter and the temperature difference between the supply and return water of the ground source heat pump unit; at this time, the water of the ground source heat pump unit releases heat to the soil through the buried pipe, and returns to the ground source heat pump unit through the ground source side cooling water pump after cooling; when the difference between the cumulative heat discharge of the ground source heat pump unit in summer and the cumulative heat intake in winter exceeds the set threshold, the second ground source heat pump condensate water switching electric valve and the fourth ground source heat pump condensate water switching electric valve are closed; the first ground source heat pump condensate water switching electric valve and the third ground source heat pump condensate water switching electric valve are opened; the water of the ground source heat pump unit enters the ground source cooling tower for heat release cooling, and the cooling water pump on the cooling tower side returns the cooling water from the ground source cooling tower to the ground source heat pump unit.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention processes and analyzes the collected local climate data, building energy consumption data, and soil thermal characteristics data throughout the year to predict the building's cooling and heating load requirements throughout the year; based on the soil thermal characteristics data, analyze the soil temperature changes when the ground source heat pump is running in winter and summer, and predict the risk of soil thermal imbalance; based on the cooling and heating load requirements throughout the year and the risk of soil thermal imbalance, formulate a year-round operation plan for the ground source heat pump to ensure the balance of heat intake and release in winter and summer, adjust the operating parameters of the ground source heat pump system in real time, and realize intelligent control of heat intake and release balance. The present invention not only improves the energy efficiency and stability of the system, but also reduces the operating cost and environmental impact, providing strong support for the further promotion and application of ground source heat pump technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1It is a structural schematic diagram of the geothermal energy supply heat balance control device of the present invention;

[0024] Figure 2 It is a schematic flow chart of the geothermal energy supply heat balance control method of the present invention.

[0025] Among them, 1-ground source heat pump unit; 2-ground source cooling tower; 3-buried pipe; 4-cooling water pump on the cooling tower side; 5-ground source side cooling water pump; 6-first ground source heat pump condensate water switching electric valve; 7-second ground source heat pump condensate water switching electric valve; 8-third ground source heat pump condensate water switching electric valve; 9-fourth ground source heat pump condensate water switching electric valve; 10-ground source field temperature monitoring device; 11-flow meter. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0029] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0030] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0033] See also Figure 1 , the present invention discloses a geothermal energy supply heat balance control device, comprising: a geothermal heat pump unit 1, a geothermal cooling tower 2, a cooling tower side cooling water pump 4, a geothermal side cooling water pump 5 and a buried pipe 3;

[0034] The water outlet of the geothermal heat pump unit 1 is connected to the water inlet of the geothermal cooling tower 2 and the water inlet of the buried pipe 3 respectively; the water outlet of the geothermal cooling tower 2 is connected to the cooling tower side cooling water pump 4; the cooling tower side cooling water pump 4 is connected to the water inlet of the geothermal heat pump unit 1; the water outlet of the buried pipe 3 is connected to the geothermal side cooling water pump 5; the geothermal side cooling water pump 5 is connected to the water inlet of the geothermal heat pump unit 1.

[0035] A first ground source heat pump condensate switching electric valve 6 is arranged between the water outlet of the ground source heat pump unit 1 and the ground source cooling tower 2; a third ground source heat pump condensate switching electric valve 8 is arranged between the cooling tower side cooling water pump 4 and the water inlet of the ground source heat pump unit 1; a fourth ground source heat pump condensate switching electric valve 9 and a flow meter 11 are arranged between the ground source side cooling water pump 5 and the water inlet of the ground source heat pump unit 1; a second ground source heat pump condensate switching electric valve 7 is arranged between the buried pipe 3 and the ground source heat pump unit 1.

[0036] A ground source field temperature monitoring device 10 is arranged near the buried pipe 3 to monitor the soil temperature at different depths near the buried pipe 3 .

[0037] The geothermal heat pump unit 1, the geothermal cooling tower 2, the cooling tower side cooling water pump 4, the first geothermal heat pump condensate water switching electric valve 6 and the third geothermal heat pump condensate water switching electric valve 8 constitute a first cooling water circulation loop; the geothermal heat pump unit 1, the buried pipe 3, the geothermal side cooling water pump 5, the second geothermal heat pump condensate water switching electric valve 7 and the fourth geothermal heat pump condensate water switching electric valve 9 constitute a second cooling water circulation loop.

[0038] See also Figure 2 The present invention discloses a geothermal energy supply heat balance control method, comprising:

[0039] S101, collects local annual climate data, building energy consumption data, and soil thermal characteristics data;

[0040] The local climate data throughout the year include: temperature and humidity of the dry-bulb thermometer, wind speed, wind direction, total radiation, direct radiation and scattered radiation; building energy consumption data include: building structure, wall material, size, orientation, building use function, personnel density and equipment configuration; soil thermal properties data include soil heat capacity, thermal conductivity and thermal diffusivity.

[0041] S102, processing and analyzing the collected data to predict the cooling and heating load demand of the building throughout the year;

[0042] Based on the collected building energy consumption data, the building envelope and other parameters are set in the energy consumption simulation software TRNSYS, and the air-conditioning system, lighting system and energy-consuming equipment are added to establish the corresponding model of the building. The collected local meteorological data are then input into TRNSYS and used as the simulated external conditions to run the simulation and obtain the building's cooling and heating loads throughout the year.

[0043] S103, based on the collected soil thermal characteristic data, analyze the soil temperature changes when the ground source heat pump unit is running in winter and summer, and predict the risk of soil thermal imbalance;

[0044] The ground source heat pump unit 1 takes heat from the soil and releases heat, takes heat for heating in winter, and discharges excess heat in the building into the soil in summer; based on the soil thermal characteristic data and the calculation results of the cooling and heating loads throughout the year, combined with the required heat intake and release from the soil, the soil temperature change is evaluated and calculated; the data collected by the ground source field temperature monitoring device 10 is collected and analyzed, the soil temperature change is observed, and compared with the historical soil temperature data and the results of the evaluation calculation, to verify the effectiveness of the control method.

[0045] S104, based on the annual cooling and heating load demand and the risk of soil thermal imbalance, formulate a year-round operation plan for the ground source heat pump unit to achieve intelligent control of heat extraction and release balance.

[0046] In winter, the second ground source heat pump condensate switching electric valve 7 and the fourth ground source heat pump condensate switching electric valve 9 are opened; the first ground source heat pump condensate switching electric valve 6 and the third ground source heat pump condensate switching electric valve 8 are closed; the water of the ground source heat pump unit 1 takes heat from the soil through the buried pipe 3, and after heating, it returns to the ground source heat pump unit 1 through the ground source side cooling water pump 5, and releases the heat to the supply building, and the ground source field temperature monitoring device 10 monitors the temperature of the soil at different depths near the buried pipe 3. At the same time, the flow monitoring data of the flow meter 11 and the supply and return water temperature difference of the ground source heat pump unit 1 are used to calculate the heat obtained from the soil in each period of winter by the ground source heat pump unit 1; in summer, the ground source heat pump unit 1 continues to work, and the ground source field temperature monitoring device 10 continues to monitor the temperature of the soil at different depths near the buried pipe 3. At the same time, the heat released by the ground source heat pump unit 1 to the soil in each period of summer is calculated by the flow monitoring data of the flow meter 11 and the supply and return water temperature difference of the ground source heat pump unit 1; at this time, the water of the ground source heat pump unit 1 releases heat to the soil through the buried pipe 3, and returns to the ground source heat pump unit 1 through the ground source side cooling water pump 5 after cooling; when the cumulative heat discharge of the ground source heat pump unit 1 in summer and the cumulative heat intake in winter differ by more than the set threshold, the second ground source heat pump condensate water switching electric valve 7 and the fourth ground source heat pump condensate water switching electric valve 9 are closed; the first ground source heat pump condensate water switching electric valve 6 and the third ground source heat pump condensate water switching electric valve 8 are opened; the water of the ground source heat pump unit 1 enters the ground source cooling tower 2 for heat release cooling, and the cooling tower side cooling water pump 4 returns the cooling water from the ground source cooling tower 2 to the ground source heat pump unit 1.

[0047] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the specific implementation modes of the present invention can still be modified or replaced by equivalents, and any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A geothermal energy supply heat balance control device, characterized in that: include: A ground source heat pump unit (1), a ground source cooling tower (2), a cooling water pump on the cooling tower side (4), a ground source side cooling water pump (5) and an underground pipe (3); The water outlet of the ground-source heat pump unit (1) is respectively connected to the water inlet of the ground-source cooling tower (2) and the water inlet of the buried pipe (3); the water outlet of the ground-source cooling tower (2) is connected to the cooling tower side cooling water pump (4); the cooling tower side cooling water pump (4) is connected to the water inlet of the ground-source heat pump unit (1); the water outlet of the buried pipe (3) is connected to the ground-source side cooling water pump (5); the ground-source side cooling water pump (5) is connected to the water inlet of the ground-source heat pump unit (1).

2. The geothermal energy supply heat balance control device according to claim 1, characterized in that: A first ground-source heat pump condensate switching electric valve (6) is arranged between the water outlet of the ground-source heat pump unit (1) and the ground-source cooling tower (2); a third ground-source heat pump condensate switching electric valve (8) is arranged between the cooling tower side cooling water pump (4) and the water inlet of the ground-source heat pump unit (1); a fourth ground-source heat pump condensate switching electric valve (9) and a flow meter (11) are arranged between the ground-source side cooling water pump (5) and the water inlet of the ground-source heat pump unit (1); and a second ground-source heat pump condensate switching electric valve (7) is arranged between the buried pipe (3) and the ground-source heat pump unit (1).

3. The geothermal energy supply heat balance control device according to claim 2, characterized in that: A ground source field temperature monitoring device (10) is arranged near the buried pipe (3) and is used to monitor the soil temperature at different depths near the buried pipe (3).

4. The geothermal energy supply heat balance control device according to claim 3, characterized in that: The geothermal heat pump unit (1), the geothermal cooling tower (2), the cooling tower side cooling water pump (4), the first geothermal heat pump condensate water switching electric valve (6) and the third geothermal heat pump condensate water switching electric valve (8) constitute a first cooling water circulation loop; the geothermal heat pump unit (1), the buried pipe (3), the geothermal side cooling water pump (5), the second geothermal heat pump condensate water switching electric valve (7) and the fourth geothermal heat pump condensate water switching electric valve (9) constitute a second cooling water circulation loop.

5. A geothermal energy supply heat balance control method, characterized in that: The geothermal energy supply heat balance control device according to claim 4 comprises: Collect local annual climate data, building energy consumption data, and soil thermal characteristics data; Process and analyze the collected data to predict the building's cooling and heating load demand throughout the year; Based on the collected soil thermal characteristics data, the soil temperature changes when the ground source heat pump unit (1) is running in winter and summer are analyzed to predict the risk of soil thermal imbalance; Based on the annual cooling and heating load demand and the risk of soil thermal imbalance, a year-round operation plan for the ground-source heat pump unit (1) is formulated to achieve intelligent control of heat extraction and release balance.

6. The geothermal energy supply heat balance control method according to claim 5, characterized in that: The local annual climate data include: temperature and humidity of the dry-bulb thermometer, wind speed, wind direction, total radiation, direct radiation and scattered radiation; building energy consumption data include: building structure, wall material, size, orientation, building use function, personnel density and equipment configuration; soil thermal property data include soil heat capacity, thermal conductivity and thermal diffusivity.

7. The geothermal energy supply heat balance control method according to claim 6, characterized in that: The annual heating and cooling load demand of the building is specifically as follows: based on the collected building energy consumption data, the building envelope and other parameters are set in the energy consumption simulation software TRNSYS, and the air-conditioning system, lighting system and energy-consuming equipment are added to establish a model corresponding to the building; the collected local meteorological data is then input into TRNSYS, and the simulation is run as the simulated external conditions to obtain the annual heating and cooling load of the building.

8. The geothermal energy supply heat balance control method according to claim 7, characterized in that: The method analyzes the soil temperature changes when the ground source heat pump unit (1) is running in winter and summer, and predicts the risk of soil thermal imbalance. Specifically, the ground source heat pump unit (1) takes heat from the soil and releases heat, takes heat for heating in winter, and discharges excess heat in the building into the soil in summer; based on the soil thermal characteristic data and the calculation results of the cooling and heating loads throughout the year, combined with the required soil heat intake and release, the soil temperature changes are evaluated and calculated; the data collected by the ground source field temperature monitoring device (10) are collected and analyzed, the soil temperature changes are observed, and compared with the historical soil temperature data and the results of the evaluation calculation to verify the effectiveness of the control method.

9. The geothermal energy supply heat balance control method according to claim 8, characterized in that: Based on the annual cooling and heating load demand and the soil thermal imbalance risk, the annual operation plan of the ground source heat pump unit (1) is formulated to achieve intelligent control of heat extraction and release balance, specifically: In winter, the second ground source heat pump condensate switching electric valve (7) and the fourth ground source heat pump condensate switching electric valve (9) are opened; the first ground source heat pump condensate switching electric valve (6) and the third ground source heat pump condensate switching electric valve (8) are closed; the water of the ground source heat pump unit (1) takes heat from the soil through the buried pipe (3), and after the temperature is increased, it returns to the ground source heat pump unit (1) through the ground source side cooling water pump (5), and releases the heat to the supply building, and the ground source field temperature monitoring device (10) monitors the temperature of the soil at different depths near the buried pipe (3); at the same time, the heat taken by the ground source heat pump unit (1) in each time period is calculated based on the flow monitoring data of the flow meter (11) and the supply and return water temperature difference of the ground source heat pump unit (1); In summer, the ground source heat pump unit (1) continues to work, and the ground source field temperature monitoring device (10) continues to monitor the temperature of the soil at different depths near the buried pipe (3); at the same time, the heat released to the soil by the ground source heat pump unit (1) at various time periods in summer is calculated based on the flow monitoring data of the flow meter (11) and the supply and return water temperature difference of the ground source heat pump unit (1); at this time, the water of the ground source heat pump unit (1) releases heat to the soil through the buried pipe (3), and after cooling, returns to the ground source heat pump unit (1) through the ground source side cooling water pump (5); when the ground source heat pump unit ( 1) When the difference between the accumulated heat rejection in summer and the accumulated heat intake in winter exceeds a set threshold, the second ground source heat pump condensate water switching electric valve (7) and the fourth ground source heat pump condensate water switching electric valve (9) are closed; the first ground source heat pump condensate water switching electric valve (6) and the third ground source heat pump condensate water switching electric valve (8) are opened; the water of the ground source heat pump unit (1) enters the ground source cooling tower (2) for heat release and cooling, and the cooling tower side cooling water pump (4) returns the cooling water from the ground source cooling tower (2) to the ground source heat pump unit (1).

Images