阅读说明：本技术 一种多联机冷热水系统及其控制方法 (Multi-split cold and hot water system and control method thereof ) 是由 陈卫星 赵永亮 牛世波 银松 于 2019-09-03 设计创作，主要内容包括：本发明公开一种多联机冷热水系统及其控制方法,涉及多联机技术领域,用于解决现有技术中多联机系统结构复杂、功能单一的问题。本发明一种多联机冷热水系统,包括室外机、以及至少两个制冷热水装置,室外机包括压缩机、室外换热器以及控制阀,制冷热水装置包括依次连接在压缩机的排气口和压缩机的吸气口之间的第一换热器、第一节流装置、第二节流装置以及第二换热器,室外换热器的第一端连接在第一节流装置和第二节流装置之间,室外换热器的第二端通过控制阀控制与压缩机的吸气口连通、或与压缩机的排气口连通；制冷热水装置还包括供水组件,供水组件能够与第一换热器、第二换热器换热。本发明的多联机冷热水系统用于供热或供冷。(The invention discloses a multi-split cold and hot water system and a control method thereof, relates to the technical field of multi-split machines, and is used for solving the problems of complex structure and single function of the multi-split machine system in the prior art. The invention relates to a multi-online cold and hot water system, which comprises an outdoor unit and at least two refrigerating and hot water devices, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger and a control valve, each refrigerating and hot water device comprises a first heat exchanger, a first throttling device, a second throttling device and a second heat exchanger which are sequentially connected between an exhaust port of the compressor and an air suction port of the compressor, the first end of the outdoor heat exchanger is connected between the first throttling device and the second throttling device, and the second end of the outdoor heat exchanger is communicated with the air suction port of the compressor or the exhaust port of the compressor through the control valve; the refrigeration hot water device also comprises a water supply assembly, and the water supply assembly can exchange heat with the first heat exchanger and the second heat exchanger. The multi-online cold and hot water system is used for supplying heat or cold.)

1. A multi-split air-conditioning system is characterized by comprising an outdoor unit and at least two refrigerating and water-heating devices, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger and a control valve, each refrigerating and water-heating device comprises a first heat exchanger, a first throttling device, a second throttling device and a second heat exchanger which are sequentially connected between an exhaust port of the compressor and an air suction port of the compressor, a first end of the outdoor heat exchanger is connected between the first throttling device and the second throttling device, and a second end of the outdoor heat exchanger is communicated with the air suction port of the compressor or the exhaust port of the compressor through the control valve; the refrigeration hot water device also comprises a water supply assembly, and the water supply assembly can exchange heat with the first heat exchanger and the second heat exchanger.

2. A multi-split cold and hot water system as claimed in claim 1, further comprising a third throttling device installed on a pipe on a side of the outdoor heat exchanger away from a discharge port of the compressor.

3. A multi-split cold and hot water system as claimed in claim 1 or 2, wherein the first heat exchanger includes a first heat exchange flow path and a second heat exchange flow path that exchange heat with each other, the first heat exchange flow path is connected in series between the exhaust port of the compressor and the first throttling device, the water supply assembly includes a first water inlet pipe and a hot water drain pipe, the first water inlet pipe is communicated with an inlet of the second heat exchange flow path, and the hot water drain pipe is communicated with an outlet of the second heat exchange flow path.

4. A multi-split cold and hot water system as claimed in claim 3, wherein the second heat exchanger includes a third heat exchange flow path and a fourth heat exchange flow path that exchange heat with each other, the third heat exchange flow path is connected in series between the second throttling device and the suction port of the compressor, the water supply assembly includes a second water inlet pipe and a cold water drain pipe, the second water inlet pipe is communicated with an inlet of the fourth heat exchange flow path, and the cold water drain pipe is communicated with an outlet of the fourth heat exchange flow path.

5. A multi-split cold and hot water system as claimed in claim 4, further comprising at least one water utilization device, the water utilization device comprising a water utilization device and a control water valve, the control water valve controlling the water utilization device to communicate with the hot water drain pipe and/or the cold water drain pipe.

6. A multi-split cold and hot water system as claimed in claim 5, wherein the water utilization device comprises one or more of a fan coil, a floor heating and a hot water supply tank.

7. A multi-split cold and hot water system as claimed in claim 1, wherein the control valve includes a housing and a valve core installed in the housing, the housing is opened with a first opening for communicating with an end of the outdoor heat exchanger, a second opening for communicating with a suction port of the compressor, and a third opening for communicating with a discharge port of the compressor, and the valve core is opened with a communication hole through which the second opening communicates with the third opening.

8. A multi-split cold and hot water system as claimed in claim 7, wherein the diameter of the communication hole is 1-2 mm.

9. A control method for a multi-split cold and hot water system as set forth in claim 5, comprising the steps of:

And controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameters of the multi-online cold and hot water system, wherein the state parameters comprise the total operation heat quantity and the total operation cold quantity of the water utilization device.

10. A control method for a multi-split cold and hot water system as claimed in claim 9, wherein the state parameters further include a discharge pressure of the compressor, and a suction pressure of the compressor.

11. A control method for a multi-split air cooling and heating system as claimed in claim 10, wherein the controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameter of the multi-split air cooling and heating system further comprises:

When the total operation heat quantity H is larger than the first return difference multiple delta of the total operation cold quantity C₁The suction pressure P_sLess than the nominal suction pressure value P of said compressor_swAnd when the second end of the outdoor heat exchanger is communicated with the exhaust port of the compressor, the control valve is controlled to control the outdoor heat exchanger to discharge the airThe second end of the outdoor heat exchanger is communicated with the air suction port of the compressor;

When the total running cold quantity C is larger than the second return difference multiple delta of the total running heat quantity H₂The exhaust pressure P_dGreater than the nominal discharge pressure value P of the compressor_dwAnd when the second end of the outdoor heat exchanger is communicated with the suction port of the compressor, controlling the control valve to communicate the second end of the outdoor heat exchanger with the exhaust port of the compressor.

12. A control method for a multi-split air-cooling and water-heating system as claimed in claim 9, wherein the water utilization device includes a fan coil, a floor heating system and a water heating tank, and before the controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameter of the multi-split air-cooling and water-heating system, the method further comprises:

obtaining indoor set temperature T_sIndoor return air temperature T_iIndoor air temperature T_rSet temperature T of water tank_dhwsTemperature T of water tank_dhw；

Calculating the total operation heat H of the water utilization device, and satisfying the following conditions: h ═ Σ H_coi(m)+ΣH_fh(n)+ΣH_dh(p)，ΣH_coi(m)＝H_coi(1)+H_coi(2)+……+H_coi(i)+……+H_coi(m)，ΣH_fh(n)＝H_fh(1)+H_fh(2)+……+H_fh(j)+......+H_fh(n)，ΣH_dh(p)＝H_dh(1)+H_dh(2)+……+H_dh(k)+……+H_dh(p)，H_coi(i)＝Q_f(i)×[T_s(i)-T_i(i)]/[T_h(i)-T_i(i)]，H_fh(j)＝Q_d(j)×[T_s(j)-T_r(j)]/[T_f(j)-T_r(j)]，H_dh(k)＝Q_w(k)×[T_dhws(k)-T_dhw(k)]/[T_w(k)-T_dhw(k)](ii) a Wherein m is the total number of fan coils in heating operation, Σ H_coi(m)Total operating heat capacity, H, of m fan coils operating for heating_coi(i) operating heat capacity of fan coil for i-th heating operation, Q_f(i) Operating capacity, T, of fan coil for the ith heating operation_h(i) The preset room temperature corresponding to the ith heating operation fan coil is set, n is the total number of floor heating systems in operation, sigma H_fh(n) is the total operating heat capacity of n floor heaters, H_fh(j) Is the operating heat capacity of the jth floor heating, Q_d(j) Is the running capacity, T, of the jth floor heating_f(j) The preset room temperature corresponding to the jth floor heating system is represented by p, the total number of the running water heating tanks, sigma H_dh(p) total operating heat capacity of p water heating tanks, H_dh(k) For the operating heat capacity of the kth hot water supply tank, Q_w(k) The capacity of the kth hot water supply tank;

Calculating the total running cold quantity C of the water utilization device, and meeting the following requirements: c ═ Σ C_coi(z)，ΣC_coi(z)＝C_coi(1)+C_coi(2)+......+C_coi(t)+......+C_coi(z)，C_coi(i)＝Q_f(t)×[T_i(t)-T_s(t)]/[T_i(t)-T_h(t)](ii) a Wherein z is the total number of fan coils in cooling operation, Σ C_coi(z) Total operating Cold Capacity of the Fan coil for z refrigeration operations, C_coi(t) the operating Cold Capacity, Q, of the fan coil for the t-th refrigeration operation_f(t) is the operating capacity of the fan coil for the tth cooling operation.

Technical Field

The invention relates to the technical field of multi-split air conditioners, in particular to a multi-split air conditioner cold and hot water system and a control method thereof.

Background

The multi-split central air conditioner is a type of central air conditioner for users, commonly called as 'one driving more', and refers to a primary refrigerant air conditioning system in which one outdoor unit is connected with two or more indoor units through a pipe, the outdoor side adopts an air cooling heat exchange mode, and the indoor side adopts a direct evaporation heat exchange mode. The existing multi-split central air conditioner has single function, and the system structure for realizing simultaneous refrigeration and heating is complex.

Disclosure of Invention

The invention provides a multi-split air-cooling and water-heating system and a control method thereof, which are used for solving the problems of complex structure and single function of a multi-split central air-conditioning system in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

In a first aspect, the invention provides a multi-split air-conditioning system, which comprises an outdoor unit and at least two refrigerating and hot water devices, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger and a control valve, and the refrigerating and hot water devices comprise a first heat exchanger, a first throttling device, a second throttling device and a second heat exchanger which are sequentially connected between an exhaust port of the compressor and an air suction port of the compressor; the first end of the outdoor heat exchanger is connected between the first throttling device and the second throttling device, and the second end of the outdoor heat exchanger is controlled by the control valve to be communicated with a suction port of the compressor or a discharge port of the compressor; the refrigeration hot water device also comprises a water supply assembly, and the water supply assembly can exchange heat with the first heat exchanger and the second heat exchanger.

the invention provides an outdoor unit in a multi-connected cold and hot water system, which comprises a compressor, an outdoor heat exchanger and a control valve, wherein a refrigerating and hot water device comprises a first heat exchanger, a first throttling device, a second throttling device and a second heat exchanger which are sequentially connected between an exhaust port of the compressor and an air suction port of the compressor, a first end of the outdoor heat exchanger is connected between the first throttling device and the second throttling device, when the control valve communicates a second end of the outdoor heat exchanger with the air suction port of the compressor, high-temperature and high-pressure refrigerant discharged from the exhaust port of the compressor enters the first heat exchanger and releases heat to water in a water supply assembly, the water temperature in the water supply assembly is increased, the heat supply function of the multi-connected cold and hot water system can be realized, the refrigerant discharged from the first heat exchanger is condensed into medium-temperature and high-pressure liquid, and the refrigerant fluid controlled, one path of refrigerant is throttled by the second throttling device and then enters the second heat exchanger to absorb heat from water in the water supply assembly, and the water in the water supply assembly is cooled, so that the cooling function of the multi-split cold and hot water system can be realized; after the other path of refrigerant releases heat through the outdoor heat exchanger, the refrigerant coming out of the second heat exchanger and the outdoor heat exchanger is evaporated into low-temperature and low-pressure refrigerant gas, and the low-temperature and low-pressure refrigerant gas returns to the air suction port of the compressor. When the control valve communicates the second end of the outdoor heat exchanger with the exhaust port of the compressor, the high-temperature and high-pressure refrigerant discharged from the exhaust port of the compressor is divided into two paths, one path of refrigerant enters the first heat exchanger to release heat, so that the heating function of the multi-split air-cooled and hot water system is realized, and then enters the first throttling device, the other path of refrigerant enters the outdoor heat exchanger to release heat, then joins with the refrigerant discharged from the first throttling device, and then enters the second heat exchanger to absorb heat after being throttled by the second throttling device, so that the cooling function of the multi-split air-cooled and hot water system is realized, and the low-temperature and low-pressure refrigerant discharged from the second heat exchanger returns to the compressor. Therefore, the multi-split cold and hot water system provided by the embodiment of the invention can realize simultaneous hot water supply and cold water supply by exchanging heat between the water supply assembly and the first heat exchanger and the second heat exchanger, and the refrigerant system in the multi-split cold and hot water system has a simple structure, does not need to install a refrigerant pipeline on the indoor side, and reduces the risk that the refrigerant leaks into the room and is difficult to treat.

In a second aspect, the present invention provides a control method for a multi-split air-cooling and water-heating system according to the above technical solution, including the following steps: and controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameters of the multi-online cold and hot water system, wherein the state parameters comprise the total operation heat quantity and the total operation cold quantity of the water utilization device.

According to the control method of the multi-split cold and hot water system, the current heating requirement and the refrigerating requirement are known according to the total operation heat and the total operation cold of the hot water equipment, the cold water equipment and the cold and hot water equipment, and the control valve is correspondingly controlled to communicate the second end of the outdoor heat exchanger with the air suction port of the compressor or the exhaust port of the compressor, so that the outdoor heat exchanger can refrigerate or heat the outdoor heat exchanger according to the specific working condition requirement, and the cooling or heating requirement of the multi-split cold and hot water system is met.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic connection diagram of a second end of an outdoor heat exchanger in a multi-split cold and hot water system according to an embodiment of the invention, which is communicated with an exhaust port of a compressor;

Fig. 2 is a schematic connection diagram of a second end of an outdoor heat exchanger in a multi-split cold and hot water system according to an embodiment of the invention, which is communicated with a suction port of a compressor;

Fig. 3 is a schematic flow chart illustrating a control method of a multi-split cold and hot water system according to an embodiment of the invention.

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, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be a mechanical connection; 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.

in the description of the present invention, "and/or" is only one kind of association relationship describing an association object, and means that there may be three kinds of relationships, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The multi-split air conditioner comprises an outdoor unit and a plurality of indoor units, and the indoor units with corresponding quantity can be installed according to actual needs. The outdoor unit is internally provided with a compressor, an outdoor heat exchanger and a throttling device which are sequentially connected end to end, the indoor unit is internally provided with an indoor heat exchanger and a fan, the indoor heat exchanger is connected in series between an air suction port of the compressor and the throttling device, and the indoor heat exchangers are connected in parallel.

referring to fig. 1 to 2, the multi-split air-cooling and water-heating system according to the embodiment of the present invention includes an outdoor unit 100, and at least two air-cooling and water-heating devices 200, where the outdoor unit 100 includes a compressor 1, an outdoor heat exchanger 2, and a control valve 3, where the air-cooling and water-heating device 200 includes a first heat exchanger 4, a first throttling device 5, a second throttling device 6, and a second heat exchanger 7, which are sequentially connected between an exhaust port of the compressor 1 and an intake port of the compressor 1, a first end 21 of the outdoor heat exchanger 2 is connected between the first throttling device 5 and the second throttling device 6, and the control valve 3 controls a second end 22 of the outdoor heat exchanger 2 to be communicated with the intake port of the compressor 1 or communicated with the exhaust port of the; the refrigeration and hot water device 200 further comprises a water supply assembly, and the water supply assembly can exchange heat with the first heat exchanger 4 and the second heat exchanger 7.

The outdoor unit 100 of the multi-split air-conditioning system comprises a compressor 1, an outdoor heat exchanger 2 and a control valve 3, wherein a refrigerating and water heating device 200 comprises a first heat exchanger 4, a first throttling device 5, a second throttling device 6 and a second heat exchanger 7 which are sequentially connected between an exhaust port of the compressor 1 and a suction port of the compressor 1, and a first end 21 of the outdoor heat exchanger 2 is connected between the first throttling device 5 and the second throttling device 6. When the control valve 3 communicates the second end 22 of the outdoor heat exchanger 2 with the air suction port of the compressor 1 (the multi-split cold and hot water system is in a first operation condition), the high-temperature and high-pressure refrigerant discharged from the air outlet of the compressor 1 enters the first heat exchanger 4 and releases heat to water in the water supply assembly, the water temperature in the water supply assembly rises, the heat supply function of the multi-split cold and hot water system can be realized, the refrigerant discharged from the first heat exchanger 4 is condensed into medium-temperature and high-pressure liquid, the refrigerant fluid controlled by the first throttling device 5 is divided into two paths, one path of refrigerant is throttled by the second throttling device 6 and then enters the second heat exchanger 7 and absorbs heat from the water in the water supply assembly, the water in the water supply assembly is cooled, and the cold supply function of the multi-split cold and; after the other path of refrigerant radiates heat through the outdoor heat exchanger 2, the refrigerant discharged from the second heat exchanger 7 and the outdoor heat exchanger 2 (serving as evaporators) is evaporated into low-temperature and low-pressure refrigerant gas, and the refrigerant gas returns to the suction port of the compressor 1. When the control valve 3 communicates the second end 22 of the outdoor heat exchanger 2 with the exhaust port of the compressor 1 (the multi-split air-cooled water-heated water system is in the second operation condition), the high-temperature and high-pressure refrigerant discharged from the exhaust port of the compressor 1 is divided into two paths, one path of refrigerant enters the first heat exchanger 4 to release heat, the heat supply function of the multi-split air-cooled water-heated water system is realized, the refrigerant enters the first throttling device 5, the other path of refrigerant enters the outdoor heat exchanger 2 (serving as a condenser) to release heat, then is merged with the refrigerant coming out of the first throttling device 5, is throttled by the second throttling device 6 and then enters the second heat exchanger 7 to absorb heat, the cold supply function of the multi-split air-cooled water-heated water system is realized, and the low-temperature and low-pressure refrigerant coming out of. Therefore, the multi-split cold and hot water system in the embodiment of the invention can realize simultaneous hot water supply and cold water supply by exchanging heat between the water supply assembly and the first heat exchanger 4 and the second heat exchanger 7, and the refrigerant system in the multi-split cold and hot water system has a simple structure, does not need to install a refrigerant pipeline on the indoor side, and reduces the risk that the refrigerant leaks into the room and is difficult to treat.

Further, the multi-split air conditioning system further comprises a third throttling device 8, and the third throttling device 8 is installed on a pipeline on the side, away from the exhaust port of the compressor 1, of the outdoor heat exchanger 2. The first throttling device 5, the second throttling device 6 and the third throttling device 8 are all electronic expansion valves; when the multi-online cold and hot water system is in the first working condition, if the second heat exchanger 7 is not needed to produce cold water, the second throttling device 6 can be closed; if there is no need to recover the heat of the outdoor heat exchanger 2, the third throttling means 8 can be turned off. When the multi-online cold and hot water system is in the second working condition, if the first heat exchanger 4 is not needed to produce hot water, the first throttling device 5 can be closed; if the cold energy of the outdoor heat exchanger 2 does not need to be recovered, the third throttling device 8 can be closed.

Optionally, the first heat exchanger 4 may exchange heat with the water supply assembly in various ways. For example, the water supply assembly comprises a first water tank, a water inlet pipe communicated with an inlet of the first water tank, and a water outlet pipe communicated with an outlet of the first water tank, the first heat exchanger 4 is placed in the first water tank, and when refrigerant flows through the first heat exchanger 4, the refrigerant can exchange heat with water in the first water tank, so that the hot water supply function of the first heat exchanger 4 is realized. For another example, the first heat exchanger 4 includes a first heat exchange flow path 41 and a second heat exchange flow path 42 that are heat-exchanged with each other, the first heat exchange flow path 41 is connected in series between the exhaust port of the compressor 1 and the first throttle device 5, the water supply assembly includes a first water inlet pipe 9 and a hot water discharge pipe 10, the first water inlet pipe 9 is communicated with an inlet of the second heat exchange flow path 42, and the hot water discharge pipe 10 is communicated with an outlet of the second heat exchange flow path 42. The latter solution does not require the first heat exchanger 4 to be immersed in water, and the outer wall of the first heat exchanger 4 is less susceptible to corrosion and is more durable.

In the same way, optionally, the water supply assembly further comprises a second water tank, a water inlet pipe communicated with an inlet of the second water tank, and a water outlet pipe communicated with an outlet of the second water tank, the second heat exchanger 7 is placed in the second water tank, and when the refrigerant flows through the second heat exchanger 7, the refrigerant can exchange heat with water in the second water tank, so that a cold water supply function of the second heat exchanger 7 is realized. Optionally, the second heat exchanger 7 includes a third heat exchange flow path 71 and a fourth heat exchange flow path 72 for exchanging heat with each other, the third heat exchange flow path 71 is connected in series between the second throttling device 6 and the suction port of the compressor 1, the water supply assembly further includes a second water inlet pipe 11 and a cold water drain pipe 12, the second water inlet pipe 11 is communicated with an inlet of the fourth heat exchange flow path 72, and the cold water drain pipe 12 is communicated with an outlet of the fourth heat exchange flow path 72. In the latter scheme, the second heat exchanger 7 does not need to be immersed in water, and the outer wall of the second heat exchanger 7 is not easy to corrode and is durable.

Fig. 1 to 2 show a specific example of a multi-split air-cooling and water-heating system according to the present invention, which includes a compressor 1, an oil separator 13 connected between an air outlet and an air inlet of the compressor 1, a three-way valve (i.e., the above-mentioned control valve is a three-way valve), an outdoor heat exchanger 2, a third throttling device 8, a first heat exchanger 4, a second heat exchanger 7, a first throttling device 5, a second throttling device 6, and a gas-liquid separator 14. When the three-way valve communicates the second end 22 of the outdoor heat exchanger 2 with the exhaust port of the compressor 1, after passing through the oil separator 13, one path of high-temperature and high-pressure refrigerant discharged from the exhaust port of the compressor 1 enters the first heat exchanger 4, after heat exchange, the medium-temperature and high-pressure refrigerant enters the first throttling device 5, after entering the three-way valve into the outdoor heat exchanger 2 for heat exchange, the other path of refrigerant enters the third throttling device 8, joins with the refrigerant discharged from the first throttling device 5, enters the second throttling device 6 for throttling, enters the second heat exchanger 7 for heat exchange, passes through the gas-liquid separator 14, and finally returns to the compressor 1. When the three-way valve communicates the second end 22 of the outdoor heat exchanger 2 with the suction port of the compressor 1, the high-temperature and high-pressure refrigerant discharged from the exhaust port of the compressor 1 passes through the oil separator 13, enters the first heat exchanger 4 for heat exchange, then enters the third throttling device 8, and is divided into two paths of refrigerants, wherein one path of refrigerant enters the outdoor heat exchanger 2 for heat exchange through the third throttling device 8, the other path of refrigerant enters the second heat exchanger 7 for heat exchange through the second throttling device 6, and the two paths of refrigerant after heat exchange are converged and then return to the suction port of the compressor 1 through the gas-liquid separator 14.

In some embodiments, the multi-split cold and hot water system according to the embodiment of the present invention further includes at least one water utilization device 300, where the water utilization device 300 includes a water utilization device and a control water valve, the control water valve controls the water utilization device to communicate with the hot water discharge pipe 10, and hot water heated by the first heat exchanger 4 is guided to the water utilization device (such as a hot water supply tank, a fan coil) through the hot water discharge pipe 10 for use; or controlling the water valve control water device to be communicated with the cold water drain pipe 12, and guiding the cold water condensed by the second heat exchange device into a water device (such as industrial circulating water equipment, an injection molding machine, a cutting machine and a fan coil) for use through the cold water drain pipe 12; or the water using device is communicated with the hot water drain pipe 10 and the cold water drain pipe 12 through the control water valve, and hot water heated by the first heat exchanger 4 and cold water condensed by the second heat exchanger 7 are respectively led into the corresponding water using devices.

It should be noted that: the water utilization device 300 comprises one or more of a fan coil 15, a floor heating 16 and a hot water supply tank 17, the fan coil 15 can exchange heat with indoor air to realize heating or refrigerating regulation of the indoor air, the floor heating 16 can meet heating requirements in winter, and the hot water supply tank 17 can directly supply hot water for users.

The water utilization device 300 shown in fig. 1-2 comprises a fan coil 15, a floor heating 16 and a hot water supply tank 17, the multi-split cold and hot water system further comprises a four-way valve 18, a main water inlet pipe 19 and a main water return pipe 20, the water inlet of the fan coil 15, the water inlet of the floor heating 16 and the water inlet of the hot water supply tank 17 are all connected with the main water inlet pipe 19 through the four-way valve 18, the water return port of the fan coil 15, the water return port of the floor heating 16 and the water return port of the hot water supply tank 17 are all communicated with the main water return pipe 20 through the four-way valve 18, a plurality of water supply branches are connected between the hot water drain pipe 10 and the cold water drain pipe 12, a plurality of water return branches are connected between the first water inlet pipe 9 and the second water inlet pipe 11, a water supply three-way valve 21 is installed on each water supply branch, a water, the hot water discharge pipe 10 is provided with a first water pump 23, and the cold water discharge pipe 12 is provided with a second water pump 24. When the fan coil 15 heats, the four-way valve 18 communicates the water inlet of the fan coil 15 with the main water inlet pipe 19, the water supply three-way valve 21 controls the hot water drain pipe 10 to communicate with the main water inlet pipe 19, and the water return three-way valve 22 controls the main water return pipe 20 to communicate with the first water inlet pipe 9; when the fan coil 15 is used for refrigerating, the four-way valve 18 communicates the water inlet of the fan coil 15 with the main water inlet pipe 19, the water supply three-way valve 21 controls the main water inlet pipe 19 to be communicated with the cold water drain pipe 12, and the water return three-way valve 22 controls the main water return pipe 20 to be communicated with the second water inlet pipe 11. Similarly, when the floor heating pipe 16 needs to work, the four-way valve 18 communicates a water inlet of the floor heating pipe 16 with the main water inlet pipe 19, the water supply three-way valve 21 controls to communicate the hot water drain pipe 10 with the main water inlet pipe 19, and the water return three-way valve 22 controls to communicate the main water return pipe 20 with the first water inlet pipe 9; when the hot water supply tank 17 needs to work, the four-way valve 18 communicates the water inlet of the hot water supply tank 17 with the main water inlet pipe 19, the water supply three-way valve 21 controls to communicate the hot water drain pipe 10 with the main water inlet pipe 19, and the water return three-way valve 22 controls to communicate the main water return pipe 20 with the first water inlet pipe 9.

The control valve 3 is a three-way valve, the control valve 3 includes a housing and a valve core installed in the housing, the housing is provided with a first opening, a second opening and a third opening, the first opening is used for being communicated with the end portion of the outdoor heat exchanger 2, the second opening is used for being communicated with the air suction port of the compressor 1, the third opening is used for being communicated with the air exhaust port of the compressor 1, the valve core is provided with a communication hole, and the second opening is communicated with the third opening through the communication hole. The pressure of the refrigerant in the pipeline connected with the second opening is low, the pressure of the refrigerant in the pipeline connected with the third opening is high, namely the refrigerant pressure difference on two sides of the valve core is large, the valve core is easy to damage, and the resistance received in the switching movement process of the valve core is large.

Furthermore, if the diameter of the communication hole is too small, the flow rate of the refrigerant between two sides of the valve core is too small, and the refrigerant or oil in the pipeline connected with the third opening is still easy to gather at the valve core; if the diameter of the communication hole is too large, the flow rate of the refrigerant in the control valve 3 is affected. Therefore, the diameter of the communication hole in the embodiment of the present invention is 1 to 2mm, and the refrigerant or oil in the pipe connected to the third port can be prevented from easily collecting at the valve body while the refrigerant flow rate of the control valve 3 is ensured.

Referring to fig. 3, an embodiment of the present invention further includes a control method for a multiple on-line cold and hot water system, including the following steps:

And controlling the control valve to communicate the second end of the outdoor heat exchanger with an air suction port of the compressor or with an air exhaust port of the compressor according to state parameters of the multi-online cold and hot water system, wherein the state parameters comprise the total operation heat quantity and the total operation cold quantity of the water utilization device.

The control valve is an electric control valve, and a control valve module of a controller of the multi-online cold and hot water system or a sub-controller which is independently used for the control valve controls the switching action of the control valve. According to the control method, the heat load and the cold load ratio of the multi-split cold and hot water system are known through the total operation heat and the total operation cold of the water utilization device, according to different working conditions, when the heat load of the multi-split cold and hot water system is high and the cold load is low, the outdoor heat exchanger is communicated with the air suction port of the compressor and serves as an evaporator, and the first heat exchanger recovers the heat of the outdoor heat exchanger, so that the heating capacity of the multi-split cold and hot water system is improved; when the multi-split cold and hot water system is low in heat load and high in cold load, the outdoor heat exchanger is communicated with the exhaust port of the compressor and serves as a condenser, outdoor heat dissipation capacity is increased, and therefore refrigerating capacity of the multi-split cold and hot water system is improved.

further, the state parameters further include a discharge pressure of the compressor and a suction pressure of the compressor. The multi-split air conditioning system further comprises a first pressure sensor and a second pressure sensor, the first pressure sensor is installed at an exhaust port of the compressor, the second pressure sensor is installed at an air suction port of the compressor, the controller can obtain exhaust pressure of the compressor from the first pressure sensor, and the second pressure sensor can obtain suction pressure of the compressor. According to the exhaust pressure of the compressor and the suction pressure of the compressor, the pressure condition of the current compressor is known, and whether the control valve is controlled to be switched or not is determined, so that the stable operation of the multi-split air-cooled hot water system is ensured.

Further, controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameters of the multi-split cold and hot water system specifically includes:

When the total operation heat quantity H is larger than the first return multiple delta of the total operation cold quantity C₁And an intake pressure P_sless than the nominal suction pressure value P of the compressor_swAnd when the second end of the outdoor heat exchanger is communicated with the exhaust port of the compressor, the control valve is controlled to communicate the second end of the outdoor heat exchanger with the suction port of the compressor.

when the total running cold quantity C is larger than the second return difference multiple delta of the total running heat quantity H₂Exhaust pressure P_dGreater than the rated discharge pressure value P of the compressor_dwAnd when the second end of the outdoor heat exchanger is communicated with the air suction port of the compressor, the control valve is controlled to communicate the second end of the outdoor heat exchanger with the air exhaust port of the compressor.

The first return difference multiple and the second return difference multiple are constants larger than 1, and once the total operation heat quantity H is larger than the total operation cold quantity C, the control valve needs to be controlled to switch.

Based on the above embodiments, the controlling the control valve to communicate the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameter of the multi-split cold and hot water system in the control method according to the embodiments of the present invention specifically includes:

And controlling a control valve to communicate the second end of the outdoor heat exchanger with an air suction port of the compressor or an air exhaust port of the compressor at intervals of preset time t according to the state parameters of the multi-online cold and hot water system.

The controller or sub-controller further includes a timing module for recording the time to change or maintain the state of the control valve. When the time for changing or maintaining the state of the control valve reaches the preset time t, whether the state of the control valve needs to be changed or not is verified again, so that the control valve can be adjusted in time, and the current working condition is adapted.

The water utilization device 300 includes a fan coil 15, a floor heating system 16 and a hot water supply tank 17, and further includes a control valve for communicating the second end of the outdoor heat exchanger with the suction port of the compressor or with the exhaust port of the compressor according to the state parameters of the multi-split cold and hot water system:

Obtaining indoor set temperature T_sIndoor return air temperature T_iIndoor air temperature T_rSet temperature T of water tank_dhwsTemperature T of water tank_dhw。

The controller or sub-controller further comprises a storage module for setting indoor set temperature T by user_sAnd/or the set temperature T of the water tank_dhwsThen, the storage module stores indoor set temperature T_sAnd the set temperature T of the water tank_dhws(ii) a A first temperature sensor is installed at an air return opening of a fan coil of the water utilization device and can detect indoor air return temperature T_i(ii) a An electronic indoor thermometer or a second temperature sensor is arranged indoors and used for detecting the indoor air temperature T_r(ii) a A third temperature sensor is arranged in the water tank and used for detecting the temperature T of the water tank_dhw。

calculating the total operation heat H of the water utilization device, and satisfying the following conditions: h ═ Σ H_coi(m)+ΣH_fh(n)+ΣH_dh(p)，ΣH_coi(m)＝H_coi(1)+H_coi(2)+......+H_coi(i)+......+H_coi(m)，ΣH_fh(n)＝H_fh(1)+H_fh(2)+......+H_fh(j)+......+H_fh(n)，ΣH_dh(p)＝H_dh(1)+H_dh(2)+......+H_dh(k)+......+H_dh(p)，H_coi(i)＝Q_f(i)×[T_s(i)-T_i(i)]/[T_h(i)-T_i(i)]，H_fh(j)＝Q_d(j)×[T_s(j)-T_r(j)]/[T_f(j)-T_r(j)]，H_dh(k)＝Q_w(k)×[T_dhws(k)-T_dhw(k)]/[T_w(k)-T_dhw(k)](ii) a Wherein m is the total number of fan coils in heating operation, Σ H_coi(m) Total operating Heat Capacity, H, of m Fan coils operating for heating_coi(i) Operating heat capacity of fan coil for i-th heating operation, Q_f(i) Operating capacity, T, of fan coil for the ith heating operation_h(i) The preset room temperature corresponding to the ith fan coil for heating operation is n, wherein n is the total number of floor heating systems in operation, sigma H_fh(n) is the total operating heat capacity of n floor heaters, H_fh(j) Is the operating heat capacity of the jth floor heating, Q_d(j) Is the running capacity, T, of the jth floor heating_f(j) The preset room temperature corresponding to the jth floor heating system is represented by p, the total number of the running water heating tanks, sigma H_dh(p) total operating heat capacity of p water heating tanks, H_dh(k) For the operating heat capacity of the kth hot water supply tank, Q_w(k) The capacity of the kth hot water supply tank.

Wherein the operating capacity Q_f(i) Rated capacity of fan coil for i heating operation, operation heat capacity H_fh(j) Rated capacity of jth floor heating, capacity Q_w(k) For the rated capacity of the kth hot water supply tank, the total number m of fan coils in heating operation can be obtained from the number of fan coils communicated with the hot water drain pipe, the total number n of floor heating in operation can be obtained from the number of floor heating in communication with the hot water drain pipe, and the total number p of hot water supply tanks in operation can be obtained from the number of hot water supply tanks communicated with the hot water drain pipe. The controller or sub-controller further includes a calculation module for calculating the total operating heat H of the water utilizing device 300.

Calculating the total running cold quantity C of the water utilization device, and satisfying the following conditions: c ═ Σ C_coi(z)，ΣC_coi(z)＝C_coi(1)+C_coi(2)+......+C_coi(t)+......+C_coi(z)，C_coi(i)＝Q_f(t)×[T_i(t)-T_s(t)]/[T_i(t)-T_h(t)](ii) a Wherein z is the total number of fan coils in cooling operation, Σ C_coi(z) Total operating Cold Capacity of the Fan coil for z refrigeration operations, C_coi(t) the operating Cold Capacity, Q, of the fan coil for the t-th refrigeration operation_f(t) is the operating capacity of the fan coil for the tth cooling operation.

Similarly, the operating capacity Q_f(t) is the rated capacity of the fan coil in the t-th refrigerating operation, the total number z of the fan coils in the refrigerating operation can be obtained from the number of the fan coils communicated with the cold water drainage pipe, and the calculating module of the controller or the sub-controller is used for calculating the total operation cold quantity C of the water utilization device.

In the description herein, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.