Switchable series-parallel connection system of air energy heat pump machine group

Abstract

The utility model provides an air energy heat pump machine group switchable series-parallel connection system which comprises a first heat pump array and a second heat pump array which are formed by connecting air energy heat pump main machines in parallel, and the first heat pump array is communicated with a water supply main pipe through a first water supply branch pipe. The first heat pump array is communicated with the water outlet main pipe through a first water outlet branch pipe; a first valve V2 is arranged on the first water outlet branch pipe; the second heat pump array is communicated with the water supply main pipe through a second water supply branch pipe; the second heat pump array is communicated with the water outlet main pipe through a second water outlet branch pipe; a second valve V1 is arranged on the second water supply branch pipe; the heat pump has the advantages that the overall operation efficiency of the heat pump is improved, precise heat supply and demand balance is achieved, and unnecessary electric energy loss and frequent starting and stopping of a main machine are reduced.

Description

Technical Field

[0001] This utility model relates to a switchable series-parallel system for air source heat pump units, and is relevant to the field of heating, ventilation and air conditioning. Background Technology

[0002] Air source heat pump heating, due to its advantages such as energy saving, environmental protection, renewable energy, good heating effect, high efficiency, and moderate investment, has become increasingly popular in northern China and represents the future direction of heating development. In practical engineering applications, multiple, even dozens, of heat pump units are needed as heat sources, forming a heat pump array. Over 95% of these arrays are connected in parallel, with a supply / return water temperature difference of only 5°C. This is insufficient for applications requiring a temperature difference greater than 5°C—for example, underfloor heating pipes require a supply / return water temperature difference greater than 5°C (generally 7-10°C), demanding lower system water flow and resulting in wasted energy from the circulating water pump. Furthermore, in older residential areas undergoing "coal-to-electricity" heating conversions, the existing heating pipes have smaller diameters. If the heat pump units are connected in parallel, the difference between the flow rate of the main unit and the flow rate at the terminal will be significant, leading to system instability. Some projects use a series configuration, which can meet heating load requirements while solving pipe diameter issues (such as small pipe diameter due to high temperature differences). However, in combined heating and cooling systems, radiators and underfloor heating require large temperature differences in winter, but fan coil units cannot meet cooling needs in summer. The array of units must be connected in parallel to meet the cooling requirements. In this case, the series system must be switched to a parallel system to allow several heat pump arrays to be freely switched between parallel and series operation, meeting the needs of different heating and cooling application scenarios such as different outlet water temperatures, temperature differences, and water flow rates. This reduces the investment cost of heating network renovation while ensuring good heating performance. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a switchable series-parallel system for air source heat pump groups that improves the overall operating efficiency of heat pumps, achieves precise heating supply and demand balance, and reduces unnecessary power consumption and frequent start-up and shutdown of the main unit.

[0004] To achieve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0005] A switchable series-parallel air source heat pump system includes a first heat pump array and a second heat pump array, each consisting of air source heat pump units connected in parallel.

[0006] The first heat pump array is connected to the main water supply pipe through the first water supply branch pipe;

[0007] The first heat pump array is connected to the main water outlet via the first water outlet branch pipe;

[0008] A first valve V2 is installed on the first outlet branch pipe;

[0009] The second heat pump array is connected to the main water supply pipe via the second water supply branch pipe;

[0010] The second heat pump array is connected to the main water outlet pipe via the second water outlet branch pipe;

[0011] A second valve V1 is installed on the second water supply branch pipe;

[0012] A series-parallel switching pipeline is installed between the first water outlet branch pipe and the second water supply branch pipe.

[0013] Furthermore, the first valve V2 and the second valve V1 are three-way valves, and the series-parallel switching pipeline connects the first valve V2 and the second valve V1.

[0014] Furthermore, the three-way valves of the first valve V2 and the second valve V1 are either electric three-way valves or manual three-way valves.

[0015] Furthermore, the diameters of the first valve V2 and the second valve V1 are the same as the diameter of the circulation pipeline.

[0016] Furthermore, the first valve V2 and the second valve V1 are two-way on / off valves, and a third valve V3 is provided on the series-parallel switching pipeline, the third valve V3 being a two-way on / off valve.

[0017] The beneficial effects of adopting the above technical solution are as follows:

[0018] The series-parallel switching of the heat pump array in the heat pump group of this utility model can not only improve the overall operating efficiency of the heat pump, but also reduce the power consumption of the water pump, achieving more economical operation and energy saving and environmental protection. It makes the supplied energy close to the demand energy, achieving precise heating and supply-demand balance, and reducing unnecessary power loss and frequent start-up and shutdown of the main unit.

[0019] This invention groups several air source heat pump units into two heat pump arrays. For example, multiple units are connected in parallel to form heat pump array 1, and several other units are connected in parallel to form heat pump array 2. The parallel connection of heat pump arrays 1 and 2 is essentially equivalent to two larger heat pump units. The two heat pump arrays are connected via pipes and three-way valves. Within the same piping system, the two heat pump arrays can operate in parallel mode or freely switch to series mode to meet the needs of different application scenarios. The series-parallel switching of the heat pump arrays can meet the needs of different heating and cooling stages with varying water flow rates, heat exchange temperature differences, and supply / return water temperature differences. While meeting the requirements, the series-parallel switching of the unit group achieves maximum energy-saving operation, reduces pipeline renovation costs, saves investment, improves system operating efficiency, minimizes overall system costs over its lifespan, and enhances the cost-effectiveness of air source heat pumps. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model;

[0021] Figure 2 This utility model employs a three-way valve in parallel operation flow diagram;

[0022] Figure 3 This utility model employs a three-way valve in series operation flow diagram;

[0023] Figure 4 This is a schematic diagram of the two-way valve structure used in this utility model;

[0024] Figure 5 This is a schematic diagram showing the flow direction of the two-way valves operating in parallel in this utility model;

[0025] Figure 6 This is a schematic diagram showing the flow direction of the two-way valves in series operation in this utility model;

[0026] 1. First heat pump array; 2. Second heat pump array; 3. Main water supply pipe; 301. First water supply branch pipe; 302. Second water supply branch pipe; 4. Main water outlet pipe; 401. First water outlet branch pipe; 402. Second water outlet branch pipe; 5. Series-parallel switching pipeline. Detailed Implementation

[0027] The present invention will be further described below with reference to the accompanying drawings.

[0028] As attached Figure 1-5As shown, this embodiment provides a switchable series-parallel air source heat pump system, which includes a first heat pump array 1 and a second heat pump array 2 composed of air source heat pump units connected in parallel. The first heat pump array 1 is connected to the main water supply pipe 3 via a first water supply branch pipe 301; the first heat pump array 1 is connected to the main water supply pipe 4 via a first water outlet branch pipe 401; a first valve V2 is installed on the first water outlet branch pipe 401; the second heat pump array 2 is connected to the main water supply pipe 3 via a second water supply branch pipe 302; the second heat pump array 2 is connected to the main water supply pipe 4 via a second water outlet branch pipe 402; the water supply pipe branches of the main water supply pipe 3 branch out into two water supply branch pipes, namely the first water supply branch pipe 301 and the second water supply branch pipe 302, from the common point A of the water supply pipe branches. The first water supply branch pipe 301 is connected to the inlet of the first heat pump array 1, and the second water supply branch pipe 302 is connected to the inlet of the second heat pump array 2, forming a water supply pipeline system. This utility model adopts the series-parallel switching of the heat pump array in the heat pump group, which can not only improve the overall operating efficiency of the heat pump, but also reduce the power consumption of the water pump, achieving more economical operation and energy saving and environmental protection. It makes the supplied energy close to the demand energy, achieving precise heating and supply-demand balance, and reducing unnecessary power loss and frequent start-up and shutdown of the main unit.

[0029] The first outlet branch pipe 401 is connected to the outlet of the first heat pump array 1, and the second outlet branch pipe 402 is connected to the outlet of the second heat pump array 2. They converge at the common point B of the outlet pipe branches and are connected to the main outlet pipe 4, forming the outlet piping system. A second valve V1 is installed on the second supply branch pipe 302; a series-parallel switching pipe 5 is installed between the first outlet branch pipe 401 and the second supply branch pipe 302. This utility model groups several air source heat pump units into two heat pump arrays. For example, in one heat pump array, multiple units are connected in parallel to form heat pump array 1, and several other units are connected in parallel to form heat pump array 2. The parallel connection forms heat pump arrays 1 and 2, which are essentially equivalent to two larger heat pump units. By reasonably connecting the two heat pump arrays through pipes and three-way valves, the two heat pump arrays can operate in parallel mode or freely switch to series mode within the same piping system to meet the needs of different application scenarios. The heat pump array enables series-parallel mode switching, which can meet the needs of different heating and cooling stages with varying water flow, heat exchange temperature difference, and supply / return water temperature difference. At the same time, by switching between series and parallel operation of the array, it can achieve the goal of maximizing energy saving, reducing pipeline renovation costs, saving investment, improving system operating efficiency, minimizing the overall cost of the system over its life cycle, and improving the cost-effectiveness of air source heat pumps.

[0030] The first valve V2 and the second valve V1 are three-way valves. These three-way valves can be electric or manual, and their diameter is the same as that of the circulation pipeline. The series-parallel switching pipeline 5 connects the first valve V2 and the second valve V1. Specifically, if the first valve V2 and the second valve V1 are three-way valves, end a of the first valve V2 is connected to the first heat pump array 1 via the first outlet branch pipe 401, and end b of the first valve V2 is connected to the common point B of the outlet pipe branch via the first outlet branch pipe 401, and then connected to the main outlet pipe 4.

[0031] The a-end of the second valve V1 is connected to the common point A of the water supply pipe branch through a pipeline, and is connected to the main water supply pipe 3. The b-end of the second valve V1 is connected to the inlet of the second heat pump array 2 through the second water supply branch pipe 302, forming a water supply pipeline system. The c-end of the first valve V2 is connected to the c-end of the second valve V1 through a series-parallel switching pipeline 5.

[0032] The first valve V2 and the second valve V1 are two-way on / off valves, and a third valve V3 is provided on the series-parallel switching pipeline 5, which is also a two-way on / off valve. That is, the use of a three-way valve or a conventional two-way valve to achieve the switching of the flow direction of the heat exchange medium in the series-parallel connection is within the scope of protection of this utility model.

[0033] Process flow description using a three-way valve structure for series / parallel switching

[0034] ① Parallel operation process flow description: such as Figure 2 As shown, the circulating medium branches off at point A, the common point of convergence of the three main water supply pipes, and enters the inlets (inlet pipes) of the first heat pump array 1 and the second heat pump array 2 respectively through the first water supply branch pipe 301 and the second water supply branch pipe 302. After being heated (or cooled), the fluid flows through the first outlet branch pipe 401 and the second outlet branch pipe 402 respectively, and then converges at point B, the common point of convergence of the outlet pipe branches, before flowing out through the main outlet pipe 4, thus achieving parallel operation. In the parallel operation process, the a-b ends of the three-way valves V1 and V2 are respectively in the on state, while the a-c ends of the three-way valve V1 are closed, and the b-c ends of the three-way valve V2 are closed.

[0035] 1. First heat pump array; 2. Second heat pump array; 3. Main water supply pipe; 301. First water supply branch pipe; 302. Second water supply branch pipe; 4. Main water outlet pipe; 401. First water outlet branch pipe; 402. Second water outlet branch pipe; 5. Series-parallel switching pipeline.

[0036] Serial operation process flow description: such as Figure 3As shown, the circulating medium branches off at point A, the common point of the system's main water supply pipe 3. One branch flows through the first water supply branch pipe 301, is heated (or cooled) once by the first heat pump array 1, and then flows through the first valve V2 (a-c ends connected, b end disconnected). It is then connected to the second valve V1 (c-b ends connected, a end disconnected) via a series-parallel switching pipeline 5, entering the inlet of the second heat pump array 2 for secondary heating (or cooling). Afterward, it flows out through point B to the main water outlet pipe 4, achieving series operation of secondary heating (or cooling) of the heat exchange fluid. In the series operation process, the c-c ends of the second valve V1 and the first valve V2 of the three-way valve are connected, while the a-b ends of the second valve V1 and the first valve V2 are closed.

[0037] Process flow description of series / parallel switching using two-way on / off valve structure

[0038] ③ Parallel operation process flow description:

[0039] like Figure 5 As shown, the circulating medium branches off at point A, the common point of convergence of the branches of the main water supply pipe 3, and the two fluids respectively enter the inlets (inlet pipes) of the first heat pump array 1 and the second heat pump array 2 through the first water supply branch pipe 301 and the second water supply branch pipe 302. After being heated (or cooled), the fluids flow through the first outlet branch pipe 401 and the second outlet branch pipe 402, respectively, and converge at point B, the common point of convergence of the outlet pipe branches, before flowing out through the main outlet pipe 4, thus achieving parallel operation. In the parallel operation process flow, the first valve V2 and the second valve V1, which are two-way on / off valves, are in the open state, while the third valve V3 is in the closed state.

[0040] ④ Description of the series operation process:

[0041] like Figure 6 As shown, the circulating medium branches off at point A, the common point of the system's main water supply pipe 3. One branch flows through the first water supply branch pipe 301, where it is heated (or cooled) once by the first heat pump array 1. Then, it flows through the third valve V3 of the series-parallel switching pipeline 5 to the inlet of the second heat pump array 2 for secondary heating (or cooling). Finally, it flows out through point B to the main water outlet pipe 4, achieving series operation of secondary heating (or cooling) of the heat exchange fluid. In this series operation process, the first valve V2 and the second valve V1, which are two-way on / off valves, are closed, while the third valve V3 is open.

[0042] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A switchable series-parallel air source heat pump system, characterized in that, It includes a first heat pump array (1) composed of air source heat pump units connected in parallel and a second heat pump array (2); The first heat pump array (1) is connected to the main water supply pipe (3) through the first water supply branch pipe (301); The first heat pump array (1) is connected to the main water outlet pipe (4) through the first water outlet branch pipe (401); A first valve V2 is installed on the first outlet branch pipe (401); The second heat pump array (2) is connected to the main water supply pipe (3) through the second water supply branch pipe (302); The second heat pump array (2) is connected to the main water outlet pipe (4) through the second water outlet branch pipe (402); A second valve V1 is installed on the second water supply branch pipe (302); A series-parallel switching pipeline (5) is provided between the first water outlet branch pipe (401) and the second water supply branch pipe (302).

2. The switchable series-parallel air source heat pump system according to claim 1, characterized in that, The first valve V2 and the second valve V1 are three-way valves, and the series-parallel switching pipeline (5) connects the first valve V2 and the second valve V1.

3. The switchable series-parallel air source heat pump system according to claim 2, characterized in that, The three-way valves of the first valve V2 and the second valve V1 are either electric three-way valves or manual three-way valves.

4. The switchable series-parallel air source heat pump system according to claim 3, characterized in that, The diameter of the first valve V2 and the second valve V1 is the same as the diameter of the circulation pipeline.

5. A switchable series-parallel air source heat pump system according to claim 1, characterized in that, The first valve V2 and the second valve V1 are two-way on / off valves. A third valve V3 is provided on the series-parallel switching pipeline (5). The third valve V3 is a two-way on / off valve.

Images