阅读说明：本技术 一种定变频耦合的新型变容量热泵系统 (Decide novel varactor heat pump system of variable frequency coupling ) 是由 梁士民 林春文 林均钊 于 2019-12-24 设计创作，主要内容包括：本发明公开了一种定变频耦合的新型变容量热泵系统,包括包括定频压缩机、变频压缩机、四通换向阀、壳管式换热器、节流装置、室外侧换热器和以及集成了数据处理程序的机组控制器,所述定频压缩机和变频压缩机并联连接,所述四通换向阀连接至壳管式换热器的第一接口,壳管式换热器的第二接口连接至节流装置,所述节流装置连接至室外侧换热器的第一接口。本发明中,该定变频耦合的新型变容量热泵系统,采用定频和变频压缩机并联,相对于传统的定频热泵系统提高了容量调节的范围,相对于传统的变频泵系统降低了成本,实用性强。(The invention discloses a fixed-frequency and variable-frequency coupled novel variable-capacity heat pump system which comprises a fixed-frequency compressor, a variable-frequency compressor, a four-way reversing valve, a shell-and-tube heat exchanger, a throttling device, an outdoor heat exchanger and a unit controller integrated with a data processing program, wherein the fixed-frequency compressor and the variable-frequency compressor are connected in parallel, the four-way reversing valve is connected to a first interface of the shell-and-tube heat exchanger, a second interface of the shell-and-tube heat exchanger is connected to the throttling device, and the throttling device is connected to a first interface of the outdoor heat exchanger. According to the novel constant-frequency and variable-frequency coupled variable-capacity heat pump system, the constant-frequency compressor and the variable-frequency compressor are connected in parallel, the capacity adjusting range is enlarged compared with that of a traditional constant-frequency heat pump system, the cost is reduced compared with that of a traditional variable-frequency pump system, and the practicability is high.)

1. A novel fixed-frequency and variable-frequency coupled variable-capacity heat pump system is characterized by comprising a fixed-frequency compressor (1), a variable-frequency compressor (11), a four-way reversing valve (6), a shell-and-tube heat exchanger (5), a throttling device (4), an outdoor heat exchanger (2) and a unit controller (7) integrated with a data processing program;

the constant-frequency compressor (1) and the variable-frequency compressor (11) are connected in parallel, the four-way reversing valve (6) is connected to a first interface of the shell-and-tube heat exchanger (5), a second interface of the shell-and-tube heat exchanger (5) is connected to the throttling device (4), the throttling device (4) is connected to a first interface of the outdoor side heat exchanger (2), a second interface of the outdoor side heat exchanger (2) is connected to the four-way reversing valve (6), and the four-way reversing valve (6) is connected to a total compressor air inlet (8);

and the air inlet of the four-way reversing valve (6) is connected with the main exhaust port, and the four-way reversing valve (6) is connected to the main air inlet of the compressor.

2. The constant-variable frequency coupled novel variable-capacity heat pump system according to claim 1, wherein the output end of the unit controller (7) is electrically connected with the input ends of the constant-frequency compressor (1), the variable-frequency compressor (11), the four-way reversing valve (6) and the throttling device (4), respectively.

3. The constant-variable frequency coupled novel variable capacitance heat pump system according to claim 1, characterized in that the unit controller (7) is composed of three components of an instruction register, a program counter and an operation controller.

4. The novel variable capacitance heat pump system of fixed variable frequency coupling according to claim 1, further comprising an outdoor side fan (3), wherein the outdoor side fan (3) is disposed outside the outdoor side heat exchanger (2), the outdoor side fan (3) can be selected from a fixed frequency fan or a direct current variable frequency fan, the fan blades are made of metal or plastic, and the output end of the unit controller (7) is electrically connected with the input end of the outdoor side fan (3).

5. The constant-frequency and variable-frequency coupled novel variable-capacity heat pump system as claimed in claim 1, wherein the shell-and-tube heat exchanger (5) comprises a shell, a heat transfer tube bundle, a tube plate, a baffle plate and a tube box, the shell is cylindrical, the tube bundle is arranged in the shell, two ends of the tube bundle are fixed on the tube plate, a refrigerant flows in the tube, water flows outside the tube, two fluids of cold and hot for heat exchange are used, and the baffle plate is arranged in the shell.

6. The novel fixed-variable-frequency-variable-coupling variable-capacity heat pump system as claimed in claim 1, wherein the outdoor heat exchanger (2) is composed of tubes and fins, the fins are mounted on a base tube, the base tube can adopt copper light tubes or internal thread copper tubes, the fins adopt copper, aluminum flat fins or corrugated fins with hydrophilic coatings, and temperature sensors are arranged on the fin heat exchanger and are electrically connected with the input end of the unit controller (7).

Technical Field

The invention relates to the technical field of heat pumps, in particular to a novel constant-frequency and variable-frequency coupled variable-capacity heat pump system.

Background

The heat pump is an energy-saving technology which is concerned worldwide in recent years, and countries in the European Union, Japan and China successively list the heat pump in the renewable energy technology category. The heat pump is widely applied to the fields of industry, agriculture, buildings and the like in China, wherein the heat pump with variable capacity has better energy-saving effect and comfort due to the capacity adjustable characteristic, becomes the mainstream technology of the current heat pump market, and has wide application space and value.

At present, a common variable-capacity heat pump system is mainly a variable-frequency heat pump system and a fixed-frequency heat pump system with a plurality of compressors connected in parallel, wherein the variable-frequency heat pump system is generally provided with a variable-frequency compressor, which has a large dynamic adjustment capacity range, but has the problems of complex control, high cost and the like, and when the operating frequency of the variable-frequency compressor is lower than 30Hz, the operating energy efficiency is reduced, so that the energy efficiency of the variable-frequency unit in low-frequency operation is not dominant under low load rate. Compared with the variable-frequency heat pump, the fixed-frequency heat pump system with a plurality of compressors connected in parallel has relatively low cost, but the dynamic regulation capacity is relatively small.

Therefore, the advantages of the fixed-frequency and variable-frequency air source heat pump are combined, and the development of a novel fixed-frequency and variable-frequency coupling variable-capacity heat pump system is very necessary, so that the regulating capacity is ensured, the cost is reduced, and the comprehensive and rapid development of the variable-capacity heat pump is promoted.

Disclosure of Invention

The invention aims to solve the defects in the prior art and provides a novel variable capacitance heat pump system with fixed frequency and variable frequency coupling.

In order to achieve the purpose, the invention adopts the following technical scheme: a novel fixed-frequency and variable-frequency coupled variable-capacity heat pump system comprises a fixed-frequency compressor, a variable-frequency compressor, a four-way reversing valve, a shell-and-tube heat exchanger, a throttling device, an outdoor heat exchanger and a unit controller integrated with a data processing program;

the constant-frequency compressor and the variable-frequency compressor are connected in parallel, the four-way reversing valve is connected to a first interface of the shell-and-tube heat exchanger, a second interface of the shell-and-tube heat exchanger is connected to a throttling device, the throttling device is connected to a first interface of the outdoor heat exchanger, a second interface of the outdoor heat exchanger is connected to the four-way reversing valve, and the four-way reversing valve is connected to a total compressor air inlet;

and the four-way reversing valve is connected to the total air inlet of the compressor.

Preferably, the output end of the unit controller is electrically connected with the input ends of the fixed-frequency compressor, the variable-frequency compressor, the four-way reversing valve and the throttling device respectively.

Preferably, the unit controller consists of three parts, namely an instruction register, a program counter and an operation controller.

Preferably, the outdoor heat exchanger further comprises an outdoor fan, the outdoor fan is arranged at the outer side of the outdoor heat exchanger, and the output end of the unit controller is electrically connected with the input end of the outdoor fan.

Preferably, the shell-and-tube heat exchanger comprises a shell, a heat transfer tube bundle, a tube plate, a baffle plate and a tube box, wherein the shell is cylindrical, the tube bundle is arranged in the shell, two ends of the tube bundle are fixed on the tube plate, a refrigerant flows in the tube, water flows out of the tube, two fluids of cold and hot for heat exchange are carried out, and the baffle plate is arranged in the shell.

Compared with the prior art, the invention has the beneficial effects that:

1. the novel constant-frequency and variable-frequency coupled variable-capacity heat pump system adopts the parallel connection of the constant-frequency compressor and the variable-frequency compressor, improves the capacity adjustment range compared with the traditional constant-frequency heat pump system, reduces the cost compared with the traditional variable-frequency pump system, and has strong practicability;

(2) the coupling mode of the constant-variable-frequency coupled novel variable-capacity heat pump system avoids the problems of low energy efficiency of a low-load variable-frequency unit and frequent start and stop of the constant-frequency unit when the unit operates, so that the unit is always in a high-efficiency operation state, and the energy utilization rate is improved;

(3) the novel constant-frequency and variable-frequency coupled variable-capacity heat pump system can be suitable for the related fields of heat supply, cold supply, constant temperature, drying and the like, and has a wide application range.

Drawings

Fig. 1 is a schematic diagram of a novel variable capacitance heat pump system with constant frequency and variable frequency coupling according to the present invention;

fig. 2 is a regulating and controlling diagram of a compressor of a fixed-frequency and variable-frequency coupled novel variable-capacity air source heat pump system provided by the invention.

Illustration of the drawings:

1. a fixed-frequency compressor; 11. a variable frequency compressor; 2. an outdoor side heat exchanger; 3. an outdoor side fan; 4. a throttling device; 5. a shell and tube heat exchanger; 6. a four-way reversing valve; 7. a unit controller.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention; the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; furthermore, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, as they may be fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1, a novel constant-frequency and variable-frequency coupled variable-capacity heat pump system comprises a constant-frequency compressor 1, a variable-frequency compressor 11, a four-way reversing valve 6, a shell-and-tube heat exchanger 5, a throttling device 4, an outdoor heat exchanger 2 and a unit controller 7 integrated with a data processing program;

the constant-frequency compressor 1 and the variable-frequency compressor 11 are connected in parallel, the four-way reversing valve 6 is connected to a first interface of the shell-and-tube heat exchanger 5, a second interface of the shell-and-tube heat exchanger 5 is connected to the throttling device 4, the throttling device 4 is connected to a first interface of the outdoor heat exchanger 2, a second interface of the outdoor heat exchanger 2 is connected to the four-way reversing valve 6, and the four-way reversing valve 6 is connected to a total compressor air inlet 8;

the air inlet of the four-way reversing valve 6 is connected with the main exhaust port, and the four-way reversing valve 6 is connected to the main air inlet of the compressor.

The output of the unit controller 7 is respectively electrically connected with the input ends of the fixed-frequency compressor 1, the variable-frequency compressor 11, the four-way reversing valve 6 and the throttling device 4, the unit controller 7 is composed of an instruction register, a program counter and an operation controller, the unit controller 7 is installed in a unit control box, and the start and stop of the fixed-frequency compressor 1, the variable-frequency compressor 11, the four-way reversing valve 6, the throttling device 4, the outdoor side fan 3 and the like can be controlled.

The outdoor heat exchanger is characterized by further comprising an outdoor fan 3, the outdoor fan 3 is arranged on the outer side of the outdoor heat exchanger 2, and the output end of the unit controller 7 is electrically connected with the input end of the outdoor fan 3.

The shell-and-tube heat exchanger 5 is composed of a shell, a heat transfer tube bundle, a tube plate, a baffle plate and a tube box, wherein the shell is cylindrical, the tube bundle is arranged in the shell, two ends of the tube bundle are fixed on the tube plate, a refrigerant flows in the tube, water flows out of the tube, two fluids of cold and hot for heat exchange are carried out, and the baffle plate is arranged in the shell.

The working principle is as follows: when the novel constant-frequency and variable-frequency coupled variable-capacity heat pump system is used, high-temperature and high-pressure refrigerant gas compressed by the constant-frequency compressor 1 and the variable-frequency compressor 11 flows into the shell-and-tube heat exchanger 5 to exchange heat with a circulating medium flowing into the shell-and-tube heat exchanger 5, the refrigerant is released and condensed into high-pressure liquid, is throttled by the throttling device 4 and then enters the outdoor heat exchanger 2 to be evaporated, and the evaporated refrigerant becomes gaseous and flows into the constant-frequency compressor 1 and the variable-frequency compressor 11 through pipelines to be circularly compressed.

The fixed-frequency compressor 1 and the variable-frequency compressor 11 can be selectively matched with a piston type compressor, a rotor type compressor and a scroll type compressor, temperature sensors and pressure sensors are respectively arranged on the total suction and exhaust pipes of the fixed-frequency compressor 1 and the variable-frequency compressor 11, and the running states of the fixed-frequency compressor 1 and the variable-frequency compressor 11 are monitored to protect the fixed-frequency compressor 1 and the variable-frequency compressor 11.

The fixed-frequency compressor 1 and the variable-frequency compressor 11 are designed and matched in the following modes:

firstly, determining the total displacement Vtotal of a system compressor according to the maximum design capacity Q of a unit;

secondly, according to the Vtotal in the first step, according to the load ratios gamma and gamma of 3/7 born by the fixed-frequency and variable-frequency compressors, respectively distributing the compressor discharge capacity V_StatorAnd V_Become；

Thirdly, combining the rotation speed of the fixed-frequency compressor 1 to be 50Hz, the cylinder volume V of the fixed-frequency compressor 1 can be firstly completed_{0 is fixed}(wherein, V_{0 is fixed}＝V_Stator50), further completing the design and model selection of the fixed-frequency compressor 1 equipment;

a fourth step of determining V in the second step_BecomeAssume V0 where V is assumed_{0 is fixed}(wherein V is assumed)_{0 is fixed}When, satisfy V_{0 change}≤5V_{0 is fixed}/3) further according to V_{0 change}＝V_Become/n_BecomeCalculating the rotational speed n of the compressor_BecomeAnd further completing the design and model selection of the inverter compressor 11.

In the actual operation process, in order to realize better matched operation of the fixed-frequency compressor and the variable-frequency compressor, the operation regulation and control method comprises the following steps:

firstly, according to the actual water supply (air outlet) temperature T of the main water supply and return pipe (air duct) of the system_gReturn water (return air) temperature T_hAnd a set temperature T_{g_set}According to the formula

Calculating the load rate phi of the unit;

and a second step of performing loading and unloading control of the compressor load according to the load rate phi of the first step and by combining a loading and unloading value corresponding to a preset load rate, wherein the loading and unloading control is as follows by way of example: if phi is less than or equal to 30, preferentially operating the fixed-frequency compressor; if phi is more than 30 and less than or equal to 70, preferentially operating the variable frequency compressor; if phi is larger than 70, the fixed frequency compressor and the variable frequency compressor are operated together.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.