Air conditioning unit and control method thereof

Abstract

The present invention discloses an air conditioning unit and a control method thereof, wherein the air conditioning unit comprises: a compressor, a four-way valve, a hot water heat exchanger and a cold water heat exchanger connected in sequence; an intermediate heat exchanger, wherein the first inlet is connected to the refrigerant outlet of the hot water heat exchanger, the first outlet is connected to the refrigerant inlet of the cold water heat exchanger, the second inlet is respectively connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the second outlet is respectively connected to the first connection point and the second connection point; a valve assembly is located on the pipeline between the intermediate heat exchanger and the hot water heat exchanger, and on the pipeline between the intermediate heat exchanger and the cold water heat exchanger, and is used to control the intermediate heat exchanger to be connected to the hot water heat exchanger, or the intermediate heat exchanger to be connected to the cold water heat exchanger. The present invention solves the problem of unbalanced cold and heat demand in the four-pipe air conditioning unit in the prior art, resulting in energy waste, improves energy utilization, and simultaneously realizes the improvement of energy output on the hot water side or the cold water side.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning, and in particular to an air conditioning unit and a control method thereof. Background Art

[0002] Air conditioning units are essential temperature control equipment for hotels and other buildings. Four-pipe units are popular because they can provide both cold and hot water. Conventional four-pipe air-cooled chillers are equipped with three heat exchangers, namely the fin heat exchanger on the air side, the hot water heat exchanger and the cold water heat exchanger on the water side. When the simultaneous cold and hot water mode is turned on, the heat exchangers involved in the circulation are the hot water heat exchanger and the cold water heat exchanger.

[0003] In actual applications, the hot water demand and cold water demand of actual applications deviate greatly from the design value of the unit, resulting in a state of excess cooling or heat. In the prior art, the solution to the above problem is to bypass hot (cold) water or refrigerant. Although this method solves the final output of the state of cold and heat balance, it is at the expense of the amount of hot (cold) water or refrigerant, and still cannot solve the problem of energy waste.

[0004] There is no effective solution to the problem of unbalanced cooling and heating demands in four-pipe air-conditioning units in related technologies, which causes energy waste. Summary of the invention

[0005] The present invention provides an air conditioning unit and a control method thereof, so as to at least solve the problem of unbalanced cooling and heating demand in a four-pipe air conditioning unit in the prior art, resulting in energy waste.

[0006] To solve the above technical problems, according to one aspect of an embodiment of the present invention, an air conditioning unit is provided, comprising:

[0007] A compressor, a four-way valve, a hot water heat exchanger and a cold water heat exchanger connected in sequence;

[0008] The intermediate heat exchanger comprises a first inlet, a first outlet, a second inlet and a second outlet; wherein the first inlet is connected to the refrigerant outlet of the hot water heat exchanger, the first outlet is connected to the refrigerant inlet of the cold water heat exchanger, the second inlet is respectively connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the second outlet is respectively connected to the first connection point and the second connection point; wherein the first connection point is located on the pipeline between the second inlet and the hot water inlet, and the second connection point is located on the pipeline between the second inlet and the chilled water inlet;

[0009] The valve assembly is located on the pipeline between the intermediate heat exchanger and the hot water heat exchanger, and on the pipeline between the intermediate heat exchanger and the cold water heat exchanger, and is used to control the communication between the intermediate heat exchanger and the hot water heat exchanger, or the communication between the intermediate heat exchanger and the cold water heat exchanger.

[0010] Further, the valve assembly comprises:

[0011] A first switch valve is located on the pipeline between the second inlet and the chilled water inlet;

[0012] A second switch valve is located on the pipeline between the second outlet and the second connection point;

[0013] A third switch valve is located on the pipeline between the second inlet and the hot water inlet;

[0014] The fourth switch valve is located on the pipeline between the second outlet and the first connection point.

[0015] Further, the D port of the four-way valve is connected to the exhaust port of the compressor, the S port of the four-way valve is connected to the suction port of the compressor, the E port of the four-way valve is connected to the refrigerant inlet of the hot water heat exchanger, and the C port of the four-way valve is connected to the refrigerant inlet of the cold water heat exchanger; the air conditioning unit also includes:

[0016] The third heat exchanger has one end connected to the C port of the four-way valve, and the other end connected to a third connection point arranged between the refrigerant inlet and the first outlet of the cold water heat exchanger.

[0017] Furthermore, it also includes:

[0018] A first one-way valve is located on the pipeline between the S port of the four-way valve and the air intake port of the compressor, and is used to prevent the refrigerant at the air intake port of the compressor from flowing back to the S port of the four-way valve; wherein a fourth connection point is provided on the pipeline between the first one-way valve and the air intake port of the compressor, and the fourth connection point is connected to the refrigerant outlet of the cold water heat exchanger;

[0019] The second one-way valve is located on the pipeline between the fourth connection point and the refrigerant outlet of the cold water heat exchanger, and is used to prevent the refrigerant at the fourth connection point from flowing back to the refrigerant outlet of the cold water heat exchanger.

[0020] Furthermore, it also includes:

[0021] The first electronic expansion valve is located on the pipeline between the third connection point and the refrigerant inlet of the cold water heat exchanger.

[0022] Furthermore, the valve assembly further includes: a fifth switch valve, located on the pipeline between the first inlet and the refrigerant outlet of the hot water heat exchanger; wherein a fifth connection point is also provided on the pipeline between the fifth switch valve and the refrigerant outlet of the hot water heat exchanger, and a sixth connection point is also provided on the pipeline between the third connection point and the first electronic expansion valve;

[0023] The air conditioning unit further includes: a second electronic expansion valve, one end of which is connected to the fifth connection point, and the other end of which is connected to the sixth connection point.

[0024] According to another aspect of an embodiment of the present invention, there is provided an air conditioning unit control method, which is applied to the air conditioning unit as described above, and the method comprises:

[0025] Detect the operating load parameters of the air-conditioning unit;

[0026] Determine the operation mode of the air conditioning unit according to the operation load parameter; wherein the operation mode includes at least: cooling mode, heating mode, forced cooling mode and forced heating mode;

[0027] Control the operation of the air conditioning unit according to the operation mode.

[0028] Furthermore, the operation mode at least includes: a simultaneous cooling and heating mode; before detecting the operation load parameter of the air-conditioning unit, it also includes:

[0029] The current operation mode of the air-conditioning unit is detected, and when the current operation mode is the simultaneous cooling and heating mode, the operation load parameter of the air-conditioning unit is triggered to be detected.

[0030] Furthermore, the operating load parameters include a hot water temperature change rate and a cold water temperature change rate; determining the operating mode of the air conditioning unit according to the operating load parameters includes:

[0031] If the cold water temperature change rate is greater than the preset maximum cold water temperature change rate and the cold water temperature change rate is greater than the hot water temperature change rate within the first preset time, the operation mode is determined to be the forced cooling mode;

[0032] If the hot water temperature change rate is greater than the preset maximum hot water temperature change rate for a second consecutive preset time, and the hot water temperature change rate is greater than the cold water temperature change rate, then the operation mode is determined to be the forced heating mode;

[0033] If the operation mode is not the forced cooling mode or the forced heating mode, it is determined that the operation mode is the cooling mode or the heating mode.

[0034] Further, after determining that the operation mode is the forced cooling mode, the method further includes: if the cold water temperature change rate is less than or equal to a preset minimum cold water temperature change rate within a first continuous preset time, exiting the forced cooling mode;

[0035] After determining that the operation mode is the forced heating mode, the method further includes: if the hot water temperature change rate is less than or equal to a preset minimum hot water temperature change rate within a second consecutive preset time, exiting the forced heating mode.

[0036] Further, controlling the operation of the air conditioning unit according to the operation mode includes:

[0037] When the operation mode is the forced cooling mode, the first solenoid valve and the second solenoid valve are controlled to be closed, the third solenoid valve and the fourth solenoid valve are opened, the fifth solenoid valve is opened, the first electronic expansion valve is opened, and the second electronic expansion valve is closed;

[0038] When the operation mode is the forced heating mode, the first solenoid valve and the second solenoid valve are controlled to be opened, the third solenoid valve and the fourth solenoid valve are closed, the fifth solenoid valve is opened, the first electronic expansion valve is opened, and the second electronic expansion valve is closed;

[0039] When the operation mode is the cooling mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is opened, and the second electronic expansion valve is closed;

[0040] When the operation mode is the heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is closed, and the second electronic expansion valve is opened;

[0041] When the operation mode is the simultaneous cooling and heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is opened, and the second electronic expansion valve is opened.

[0042] According to another aspect of an embodiment of the present invention, there is provided a storage medium comprising computer executable instructions, wherein the computer executable instructions are used to execute the air conditioning unit control method as described above when executed by a computer processor.

[0043] In the present invention, an air conditioning unit is provided, which is provided with an intermediate heat exchanger, connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the intermediate heat exchanger is connected to the hot water heat exchanger or the intermediate heat exchanger is connected to the cold water heat exchanger through a valve assembly. Through the intermediate heat exchanger, the surplus energy on the hot water side (cold water side) is transferred to the cold water side (hot water side), the surplus energy is fully utilized, thereby improving the energy utilization rate, and at the same time achieving the improvement of the energy output on the hot water side or the cold water side. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic diagram of an optional structure of an air conditioning unit according to an embodiment of the present invention;

[0045] Figure 2 is an optional flow chart of an air conditioning unit control method according to an embodiment of the present invention;

[0046] Figure 3 is another optional flow chart of the air conditioning unit control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0048] Example 1

[0049] In a preferred embodiment 1 of the present invention, an air conditioning unit is provided. Specifically, Figure 1 An optional structural diagram of the air conditioning unit is shown, such as Figure 1 As shown, the air conditioning unit includes:

[0050] A compressor 1, a four-way valve 2, a hot water heat exchanger 7 and a cold water heat exchanger 6 connected in sequence;

[0051] The intermediate heat exchanger 11 comprises a first inlet 111, a first outlet 112, a second inlet 113 and a second outlet 114; wherein the first inlet 111 is connected to the refrigerant outlet of the hot water heat exchanger 7, the first outlet 112 is connected to the refrigerant inlet of the cold water heat exchanger 6, the second inlet 113 is respectively connected to the hot water inlet of the hot water heat exchanger 7 and the chilled water inlet of the cold water heat exchanger 6, and the second outlet 114 is respectively connected to the first connection point and the second connection point; wherein the first connection point is located on the pipeline between the second inlet 113 and the hot water inlet, and the second connection point is located on the pipeline between the second inlet 113 and the chilled water inlet;

[0052] The valve assembly is located on the pipeline between the intermediate heat exchanger 11 and the hot water heat exchanger 7, and on the pipeline between the intermediate heat exchanger 11 and the cold water heat exchanger 6, and is used to control the communication between the intermediate heat exchanger 11 and the hot water heat exchanger 7, or the communication between the intermediate heat exchanger 11 and the cold water heat exchanger 6.

[0053] In the above embodiment, an air conditioning unit is provided, which is provided with an intermediate heat exchanger, connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the intermediate heat exchanger is connected to the hot water heat exchanger or the intermediate heat exchanger is connected to the cold water heat exchanger through a valve assembly. Through the intermediate heat exchanger, the surplus energy on the hot water side (cold water side) is transferred to the cold water side (hot water side), the surplus energy is fully utilized, thereby improving the energy utilization rate, and at the same time achieving the improvement of the energy output on the hot water side or the cold water side.

[0054] like Figure 1As shown, the valve assembly includes: a first switch valve 14, located on the pipeline between the second inlet 113 and the chilled water inlet; a second switch valve 12, located on the pipeline between the second outlet 114 and the second connection point; a third switch valve 15, located on the pipeline between the second inlet 113 and the hot water inlet; a fourth switch valve 13, located on the pipeline between the second outlet 114 and the first connection point. The above-mentioned switch valves can be solenoid valves, butterfly valves, or other forms of switch valves.

[0055] In addition, the valve assembly further includes: a fifth switch valve 10, which is located on the pipeline between the first inlet 111 and the refrigerant outlet of the hot water heat exchanger 7. The fifth switch valve 10 can control the state of the intermediate heat exchanger 11 and determine whether to start the intermediate heat exchanger 11.

[0056] Among them, the D port of the four-way valve 2 is connected to the exhaust port of the compressor 1, the S port of the four-way valve 2 is connected to the suction port of the compressor 1, the E port of the four-way valve 2 is connected to the refrigerant inlet of the hot water heat exchanger 7, and the C port of the four-way valve 2 is connected to the refrigerant inlet of the cold water heat exchanger 6; based on the above connection relationship, the air conditioning unit also includes: a third heat exchanger 3, one end of which is connected to the C port of the four-way valve 2, and the other end is connected to the third connection point arranged between the refrigerant inlet of the cold water heat exchanger 6 and the first outlet 112. The third heat exchanger 3 is a fin heat exchanger or other forms of heat exchanger, which is used to cooperate with the hot water heat exchanger 7 or the cold water heat exchanger 6 to perform a complete refrigerant cycle in the conventional cooling or heating mode.

[0057] In addition, the air-conditioning unit also includes: a first one-way valve 8, which is located on the pipeline between the S port of the four-way valve 2 and the suction port of the compressor 1, and is used to prevent the refrigerant at the suction port of the compressor 1 from flowing back to the S port of the four-way valve 2; wherein a fourth connection point is provided on the pipeline between the first one-way valve 8 and the suction port of the compressor 1, and the fourth connection point is connected to the refrigerant outlet of the cold water heat exchanger 6; a second one-way valve 9, which is located on the pipeline between the fourth connection point and the refrigerant outlet of the cold water heat exchanger 6, and is used to prevent the refrigerant at the fourth connection point from flowing back to the refrigerant outlet of the cold water heat exchanger 6.

[0058] In order to control the flow direction of the refrigerant and realize different operation modes, the air conditioning unit further includes: a first electronic expansion valve 4 , which is located on the pipeline between the third connection point and the refrigerant inlet of the cold water heat exchanger 6 .

[0059] A fifth connection point is also arranged on the pipeline between the fifth switch valve 10 and the refrigerant outlet of the hot water heat exchanger 7, and a sixth connection point is also arranged on the pipeline between the third connection point and the first electronic expansion valve 4; the air-conditioning unit also includes: a second electronic expansion valve 5, one end of which is connected to the fifth connection point and the other end is connected to the sixth connection point.

[0060] The first electronic expansion valve 4 and the second electronic expansion valve 5 can realize control of different operation modes in combination with the fifth switch valve 10. The operation modes of the air conditioning unit include: simultaneous cooling and heating mode, cooling mode, heating mode, forced cooling mode and forced heating mode.

[0061] In the forced cooling mode, the cooling load is greater than the heating load. At this time, the third switch valve 15 and the fourth switch valve 13 are opened, and part of the hot water is taken from the hot water inlet side to exchange heat with the medium-temperature refrigerant condensed from the hot water heat exchanger 7. Since this part of the hot water is the water after heat exchange from the user side, its temperature is lower than the temperature of the refrigerant condensed from the hot water heat exchanger 7, so the heat of the refrigerant is partially released to this part of the hot water to be supercooled. From the refrigeration principle, it can be known that increasing the supercooling degree can increase the refrigeration capacity of the unit mass of the refrigerant; at the same time, the temperature of this part of the hot water is increased and mixed with the chilled water inlet, so that the inlet temperature is increased, and the evaporation temperature of the refrigerant in the chilled water heat exchanger is increased, and the refrigeration capacity is also increased. In the whole process, the supercooling degree and evaporation temperature of the system refrigerant are increased to provide refrigeration capacity, which is equivalent to transferring the excess heat on the hot water side to the cold water side, and the surplus energy is fully utilized to improve the energy utilization rate.

[0062] In the forced heating mode, the heating load is greater than the cooling load. At this time, the first switch valve 14 and the second switch valve 12 are opened, and part of the chilled water is taken from the chilled water inlet side to exchange heat with the medium-temperature refrigerant condensed from the hot water heat exchanger 7. Therefore, part of the heat of the refrigerant is released to this part of the hot water to obtain supercooling. From the refrigeration principle, it can be known that increasing the supercooling degree can increase the cooling capacity of the unit mass of the refrigerant; according to the reverse refrigerant cycle principle, the heating capacity ≈ cooling capacity + compressor 1 power. Since this process increases the supercooling degree, the cooling capacity of the unit mass of the refrigerant is provided, which can indirectly increase the heating capacity. It is equivalent to transferring the surplus heat on the chilled water side to the hot water side, and the surplus energy is fully utilized, thereby improving the energy utilization rate.

[0063] In summary, the ultimate realization principle of the forced cooling mode and the forced heating mode is the same, but the difference is that in the forced cooling mode, hot water is taken into the intermediate heat exchanger 11, because the demand for hot water is small at this time, and taking a part of it does not affect the demand on the user side. In the forced heating mode, cold water is taken into the intermediate heat exchanger 11, because the demand for chilled water is small at this time, and taking a part of it does not affect the demand on the user side.

[0064] Example 2

[0065] In a preferred embodiment 2 of the present invention, a method for controlling an air conditioning unit is provided, which is applied to the air conditioning unit in the above embodiment 1. Specifically, Figure 2 An optional flow chart of the method is shown as follows: Figure 2 As shown, the method includes the following steps S202-S206:

[0066] S202: Detecting the operating load parameters of the air conditioning unit;

[0067] S204: Determine the operation mode of the air conditioning unit according to the operation load parameter; wherein the operation mode at least includes: cooling mode, heating mode, forced cooling mode and forced heating mode;

[0068] S206: Control the operation of the air conditioning unit according to the operation mode.

[0069] In the above embodiment, an air conditioning unit is provided, which is provided with an intermediate heat exchanger, connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the intermediate heat exchanger is connected to the hot water heat exchanger or the intermediate heat exchanger is connected to the cold water heat exchanger through a valve assembly. Through the intermediate heat exchanger, the surplus energy on the hot water side (cold water side) is transferred to the cold water side (hot water side), the surplus energy is fully utilized, thereby improving the energy utilization rate, and at the same time achieving the improvement of the energy output on the hot water side or the cold water side.

[0070] The operation mode at least includes: a simultaneous cooling and heating mode; before detecting the operation load parameter of the air-conditioning unit, it also includes:

[0071] Detect the current operation mode of the air-conditioning unit. When the current operation mode is the simultaneous cooling and heating mode, trigger the detection of the operation load parameters of the air-conditioning unit. In the case of simultaneous cooling and heating, there will be a demand for forced cooling or forced heating. Therefore, in the cooling and heating mode, trigger the detection of the operation load parameters of the air-conditioning unit to determine the operation mode of the air-conditioning unit according to the operation load parameters.

[0072] Specifically, the operating load parameters include the hot water temperature change rate and the cold water temperature change rate; the operating mode of the air-conditioning unit is determined according to the operating load parameters, including: if the cold water temperature change rate is greater than the preset maximum cold water temperature change rate, and the cold water temperature change rate is greater than the hot water temperature change rate within the first consecutive preset time, then the operating mode is determined to be a forced cooling mode; if the hot water temperature change rate is greater than the preset maximum hot water temperature change rate, and the hot water temperature change rate is greater than the cold water temperature change rate within the second consecutive preset time, then the operating mode is determined to be a forced heating mode; if the operating mode is not a forced cooling mode or a forced heating mode, then the operating mode is determined to be a cooling mode or a heating mode. The basic principle of the above judgment is: when the heating load demand is greater than the cooling load demand, the forced heating mode is operated; when the heating load demand is less than the cooling load demand, the forced cooling mode is operated. Only one of the forced heating and forced cooling modes can be selected and cannot coexist at the same time. When the unit is neither in the forced cooling mode nor in the forced heating mode, it is in the conventional cooling or heating mode. The conventional cooling or heating mode can be determined according to the operating mode displayed on the control panel, and the operating mode can be determined by the unit according to the operating conditions, or can be an operating mode input by the user.

[0073] After determining that the operating mode is the forced cooling mode, it also includes: if the cold water temperature change rate is less than or equal to the preset minimum cold water temperature change rate within a first consecutive preset time, then exit the forced cooling mode; after determining that the operating mode is the forced heating mode, it also includes: if the hot water temperature change rate is less than or equal to the preset minimum hot water temperature change rate within a second consecutive preset time, then exit the forced heating mode.

[0074] Specifically, controlling the operation of the air conditioning unit according to the operation mode includes:

[0075] When the operation mode is the forced cooling mode, the first solenoid valve and the second solenoid valve are controlled to be closed, the third solenoid valve and the fourth solenoid valve are opened, the fifth solenoid valve is opened, the first electronic expansion valve is opened, and the second electronic expansion valve is closed; at this time, the refrigerant flows as follows: compressor 1 → port D of four-way valve 2 (no electricity) → port E of four-way valve 2 → hot water heat exchanger 7 → solenoid valve 10 → heat exchanger 11 → electronic expansion valve 4 → chilled water heat exchanger 6 → check valve 9 → compressor 1;

[0076] When the operation mode is the forced heating mode, the first solenoid valve and the second solenoid valve are controlled to be opened, the third solenoid valve and the fourth solenoid valve are closed, the fifth solenoid valve is opened, the first electronic expansion valve is opened, and the second electronic expansion valve is closed; at this time, the refrigerant flow direction is: compressor 1 → D port of four-way valve 2 (electric reversing) → E port of four-way valve 2 → hot water heat exchanger 7 → solenoid valve 10 → heat exchanger 11 → electronic expansion valve 4 → chilled water heat exchanger 6 → check valve 9 → compressor 1;

[0077] When the operation mode is cooling mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is opened, and the second electronic expansion valve is closed; at this time, the refrigerant flows as follows: compressor 1 → port D of four-way valve 2 (no electricity) → port C of four-way valve 2 → fin heat exchanger 3 → electronic expansion valve 4 → chilled water heat exchanger 6 → check valve 9 → compressor 1;

[0078] When the operation mode is heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is closed, and the second electronic expansion valve is opened; at this time, the refrigerant flows as follows: compressor 1 → port D of four-way valve 2 (electric reversing) → port E of four-way valve 2 → hot water heat exchanger 7 → electronic expansion valve 5 → fin heat exchanger 3 → four-way valve 2 → check valve 8 → compressor 1;

[0079] When the operation mode is the simultaneous cooling and heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is opened, and the second electronic expansion valve is opened. At this time, the refrigerant flows as follows: compressor 1 → port D of four-way valve 2 (powered) → port E of four-way valve 2 → hot water heat exchanger 7 → electronic expansion valve 4 → chilled water heat exchanger 6 → check valve 9 → compressor 1. The simultaneous cooling and heating mode can be a simultaneous cooling and heating mode before the forced cooling mode or the forced heating mode, or a simultaneous cooling and heating mode selected according to user needs.

[0080] Another air conditioning unit control method is provided in a preferred embodiment 2 of the present invention. Specifically, Figure 3 An optional flow chart of the method is shown as follows: Figure 3 As shown, the method includes the following steps S301-S310:

[0081] S301: running in simultaneous cooling and heating mode;

[0082] S302: Detect the cold water temperature change rate △TC for a continuous tc time (first preset time), △TC = TCout t -TCout (t-60) ;

[0083] S303: Determine whether △TC>TC1 and △TC>△TH are established; wherein TC1 is the upper limit of the cold water temperature change rate, △TH is the hot water temperature change rate, △TH=THout t -THout (t-60) ; If yes, execute step S304, if not, execute step S305;

[0084] S304: If yes, enter the forced cooling mode, open SV0 (fifth switch valve), SV3 (third switch valve), SV4 (fourth switch valve), close SV1 (first switch valve), SV2 (first switch valve); the process ends;

[0085] S305: If no, close SV3 (third switch valve), SV4 (fourth switch valve), close SV1 (first switch valve), SV2 (second switch valve); then, enter step S310;

[0086] S306: Detecting the hot water temperature change rate ΔTH for th time (second preset time);

[0087] S307: Determine whether △TH>TH1 and △TH>△TC are established; wherein TH1 is the upper limit of the rate of change of the hot water temperature; if yes, execute step S308; if not, execute step S309;

[0088] S308: If yes, enter the forced heating mode, open SV0 (fifth switch valve), SV1 (first switch valve), SV2 (second switch valve), close SV3 (third switch valve), SV4 (fourth switch valve); the process ends;

[0089] S309: If not, close SV1 (first switch valve), SV2 (second switch valve), close SV3 (third switch valve), SV4 (fourth switch valve); then execute step S310;

[0090] S310: Close SV0 (fifth switch valve); when the hot water temperature change rate △TH for th consecutive time ≤ the lower limit of the hot water change rate TH2, exit the forced heating mode; when the cold water temperature change rate △TC for tc consecutive time ≤ the upper limit of the chilled water change rate TC2, exit the forced cooling mode; exit the forced cooling or forced heating mode, and only run the conventional cooling or heating mode, at this time control to close SV0 (fifth switch valve).

[0091] Example 3

[0092] Based on the air conditioning unit control method provided in the above-mentioned embodiment 2, a storage medium containing computer executable instructions is also provided in a preferred embodiment 3 of the present invention. When the computer executable instructions are executed by a computer processor, they are used to execute the air conditioning unit control method as described above.

[0093] In the above embodiment, an air conditioning unit is provided, which is provided with an intermediate heat exchanger, connected to the hot water inlet of the hot water heat exchanger and the chilled water inlet of the cold water heat exchanger, and the intermediate heat exchanger is connected to the hot water heat exchanger or the intermediate heat exchanger is connected to the cold water heat exchanger through a valve assembly. Through the intermediate heat exchanger, the surplus energy on the hot water side (cold water side) is transferred to the cold water side (hot water side), the surplus energy is fully utilized, thereby improving the energy utilization rate, and at the same time achieving the improvement of the energy output on the hot water side or the cold water side.

[0094] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not invented by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0095] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An air conditioning unit, characterized in that: include: A compressor (1), a four-way valve (2), a hot water heat exchanger (7) and a cold water heat exchanger (6) are connected in sequence; and further comprises: The intermediate heat exchanger (11) comprises a first inlet (111), a first outlet (112), a second inlet (113) and a second outlet (114); wherein the first inlet (111) is connected to the refrigerant outlet of the hot water heat exchanger (7), the first outlet (112) is connected to the refrigerant inlet of the cold water heat exchanger (6), the second inlet (113) is respectively connected to the hot water inlet of the hot water heat exchanger (7) and the chilled water inlet of the cold water heat exchanger (6), and the second outlet (114) is respectively connected to a first connection point and a second connection point; wherein the first connection point is located on the pipeline between the second inlet (113) and the hot water inlet, and the second connection point is located on the pipeline between the second inlet (113) and the chilled water inlet; a valve assembly, located on the pipeline between the intermediate heat exchanger (11) and the hot water heat exchanger (7), and on the pipeline between the intermediate heat exchanger (11) and the cold water heat exchanger (6), and used to control the communication between the intermediate heat exchanger (11) and the hot water heat exchanger (7), or the communication between the intermediate heat exchanger (11) and the cold water heat exchanger (6); The valve assembly comprises: A first switch valve (14) is located on the pipeline between the second inlet (113) and the chilled water inlet; a second switch valve (12), located on the pipeline between the second outlet (114) and the second connection point; A third switch valve (15) is located on the pipeline between the second inlet (113) and the hot water inlet; The fourth switch valve (13) is located on the pipeline between the second outlet (114) and the first connection point.

2. The air conditioning unit according to claim 1, characterized in that: The D port of the four-way valve (2) is connected to the exhaust port of the compressor (1), the S port of the four-way valve (2) is connected to the intake port of the compressor (1), the E port of the four-way valve (2) is connected to the refrigerant inlet of the hot water heat exchanger (7), and the C port of the four-way valve (2) is connected to the refrigerant inlet of the cold water heat exchanger (6); The air conditioning unit further comprises: a third heat exchanger (3), one end of which is connected to the C port of the four-way valve (2), and the other end of which is connected to a third connection point arranged between the refrigerant inlet of the cold water heat exchanger (6) and the first outlet (112).

3. The air conditioning unit according to claim 2, characterized in that: Also includes: A first one-way valve (8) is located on the pipeline between the S port of the four-way valve (2) and the air intake port of the compressor (1), and is used to prevent the refrigerant at the air intake port of the compressor (1) from flowing back to the S port of the four-way valve (2); wherein a fourth connection point is provided on the pipeline between the first one-way valve (8) and the air intake port of the compressor (1), and the fourth connection point is connected to the refrigerant outlet of the cold water heat exchanger (6); The second one-way valve (9) is located on the pipeline between the fourth connection point and the refrigerant outlet of the cold water heat exchanger (6), and is used to prevent the refrigerant at the fourth connection point from flowing back to the refrigerant outlet of the cold water heat exchanger (6).

4. The air conditioning unit according to claim 2, characterized in that: Also includes: The first electronic expansion valve (4) is located on the pipeline between the third connection point and the refrigerant inlet of the cold water heat exchanger (6).

5. The air conditioning unit according to claim 4, characterized in that: The valve assembly further comprises: a fifth switch valve (10), which is located on the pipeline between the first inlet (111) and the refrigerant outlet of the hot water heat exchanger (7); wherein a fifth connection point is also provided on the pipeline between the fifth switch valve (10) and the refrigerant outlet of the hot water heat exchanger (7), and a sixth connection point is also provided on the pipeline between the third connection point and the first electronic expansion valve (4); The air conditioning unit further comprises: a second electronic expansion valve (5), one end of which is connected to the fifth connection point, and the other end of which is connected to the sixth connection point.

6. A method for controlling an air conditioning unit, applied to the air conditioning unit according to any one of claims 1 to 5, characterized in that: The method comprises: Detect the operating load parameters of the air-conditioning unit; Determining the operating mode of the air conditioning unit according to the operating load parameter; wherein the operating mode includes at least: cooling mode, heating mode, forced cooling mode and forced heating mode; The operation of the air conditioning unit is controlled according to the operation mode.

7. The method according to claim 6, characterized in that The operation mode at least includes: a simultaneous cooling and heating mode; before detecting the operation load parameter of the air-conditioning unit, it also includes: The current operation mode of the air-conditioning unit is detected, and when the current operation mode is the simultaneous cooling and heating mode, the operation load parameter of the air-conditioning unit is triggered.

8. The method according to claim 6, characterized in that The operating load parameters include the hot water temperature change rate and the cold water temperature change rate; Determining the operating mode of the air conditioning unit according to the operating load parameter includes: If the cold water temperature change rate is greater than the preset maximum cold water temperature change rate and the cold water temperature change rate is greater than the hot water temperature change rate within a first preset continuous time, then the operation mode is determined to be a forced cooling mode; If the hot water temperature change rate is greater than the preset maximum hot water temperature change rate for a second consecutive preset time, and the hot water temperature change rate is greater than the cold water temperature change rate, then the operation mode is determined to be the forced heating mode; If the operation mode is not the forced cooling mode or the forced heating mode, it is determined that the operation mode is the cooling mode or the heating mode.

9. The method according to claim 8, characterized in that After determining that the operation mode is the forced cooling mode, the method further includes: if the cold water temperature change rate is less than or equal to a preset minimum cold water temperature change rate within the first preset time, exiting the forced cooling mode; After determining that the operation mode is the forced heating mode, the method further includes: if the hot water temperature change rate is less than or equal to a preset minimum hot water temperature change rate within the second preset time, exiting the forced heating mode.

10. The method according to claim 7, characterized in that Controlling the operation of the air conditioning unit according to the operation mode includes: When the operation mode is the forced cooling mode, the first solenoid valve and the second solenoid valve are controlled to be closed, the third solenoid valve and the fourth solenoid valve are opened, the fifth solenoid valve is opened, the first electronic expansion valve is opened, and the second electronic expansion valve is closed; When the operation mode is the forced heating mode, the first solenoid valve and the second solenoid valve are controlled to be opened, the third solenoid valve and the fourth solenoid valve are controlled to be closed, the fifth solenoid valve is controlled to be opened, the first electronic expansion valve is controlled to be opened, and the second electronic expansion valve is controlled to be closed; When the operation mode is the cooling mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is opened, and the second electronic expansion valve is closed; When the operation mode is the heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, and the fifth solenoid valve are controlled to be closed, the first electronic expansion valve is closed, and the second electronic expansion valve is opened; When the operation mode is the simultaneous cooling and heating mode, the first solenoid valve, the second solenoid valve, the third solenoid valve, the fourth solenoid valve, and the fifth solenoid valve are controlled to be closed, and the first electronic expansion valve and the second electronic expansion valve are controlled to be opened.

11. A storage medium containing computer executable instructions, characterized in that: The computer executable instructions are used to execute the air conditioning unit control method according to any one of claims 6 to 10 when executed by a computer processor.

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