A cascade heat pump triple-generation unit

Abstract

The utility model discloses a kind of cascade heat pump triple combination unit, including composite heat exchanger, first condenser and evaporator, composite heat exchanger is equipped with the first working medium passage for first refrigerant to flow through heat absorption, and the second working medium passage for second refrigerant to flow through heat release;First condenser is equipped with the third working medium passage for first refrigerant to flow through heat release, and the first medium passage for industrial water to flow through heat absorption;The outlet of first working medium passage is communicated with the inlet of third working medium passage, and the outlet of third working medium passage is communicated with the inlet of first working medium passage, and first compressor is equipped with first expansion valve between;Evaporator is equipped with the fourth working medium passage for second refrigerant to flow through heat absorption, and the second medium passage for air conditioning water to flow through heat release;The outlet of fourth working medium passage is communicated with the inlet of second working medium passage, and the outlet of second working medium passage is communicated with the inlet of fourth working medium passage, and second compressor is equipped with second expansion valve between, the utility model can improve energy efficiency.

Description

Technical Field

[0001] This utility model relates to the technical field of cooling and heating equipment, specifically to a cascade heat pump tri-generation unit. Background Technology

[0002] Cascade high-temperature heat pump systems are an innovative heat pump technology that can provide high-quality heat energy. They are widely used in industrial applications that require high-temperature hot water, steam, or process heat energy, such as coating ovens, food processing, and chemical and pharmaceutical industries.

[0003] Traditional cascade high-temperature heat pump systems, such as Figure 1 As shown, the system includes a first heat exchanger 01, a second heat exchanger 02, and a third heat exchanger 03. The first heat exchanger 01 has a first working fluid channel and a second working fluid channel. The second heat exchanger 02 has a third working fluid channel and a medium channel. The third heat exchanger 03 has a fourth working fluid channel. The first and third working fluid channels are used for the flow of a first refrigerant. A first compressor 04 and a first four-way valve 05 are sequentially connected between one end of the first working fluid channel and one end of the third working fluid channel. A first expansion valve 06 is connected between the other ends of the first and third working fluid channels. The second and fourth working fluid channels are used for the flow of a second refrigerant. A second four-way valve 07 and a second compressor 08 are sequentially connected between one end of the second and one end of the fourth working fluid channel. A second expansion valve 09 is connected between the other ends of the second and fourth working fluid channels. The medium channel is used for the flow of industrial water. When the cascade high-temperature heat pump system is in heating operation, the second refrigerant, which is in a low-temperature, low-pressure gaseous state and flows through the fourth working fluid channel, first absorbs heat from the air and is compressed into a high-temperature, high-pressure gaseous state by the second compressor 08. Then, it flows through the second working fluid channel, releases heat, and becomes a high-temperature, high-pressure liquid. It then passes through the second expansion valve 09, which throttles and reduces the pressure, returning it to a low-temperature, low-pressure liquid state. Finally, it passes through the third heat exchanger 03 and evaporates back into a low-temperature, low-pressure gaseous state. At the same time, the first refrigerant, which is in a low-temperature, low-pressure liquid state, flows through the first working fluid channel, absorbs heat released by the second refrigerant, and evaporates into a low-temperature, low-pressure gaseous state. Then, it passes through the first compressor 04, which compresses it into a high-temperature, high-pressure gaseous state. It then flows through the third working fluid channel, releases heat, and becomes a high-temperature, high-pressure liquid state. Finally, it passes through the first expansion valve 06, which throttles and reduces the pressure, returning it to a low-temperature, low-pressure liquid state. Finally, it flows through the first heat exchanger 01. This causes the industrial water flowing through the medium channel to absorb heat released by the first refrigerant and continuously heat up to form the high-temperature hot water required for industry.

[0004] However, the aforementioned cascade high-temperature heat pump system has limited effective utilization of the generated energy and low energy efficiency. Utility Model Content

[0005] This invention provides a cascade heat pump tri-generation unit, which solves the technical problems of limited effective utilization of generated energy and low energy efficiency in existing cascade high-temperature heat pump systems.

[0006] In view of this, the present invention provides a cascade heat pump tri-generation unit, comprising:

[0007] The composite heat exchanger has a first working fluid channel and a second working fluid channel. The first working fluid channel is used for the first refrigerant to flow through and absorb heat, and the second working fluid channel is used for the second refrigerant to flow through and release heat.

[0008] The first condenser has a third working fluid channel and a first medium channel. The third working fluid channel is used for the first refrigerant to flow through and release heat, and the first medium channel is used for the industrial water to flow through and absorb heat. A first compressor is connected between the outlet of the first working fluid channel and the inlet of the third working fluid channel, and a first expansion valve is connected between the outlet of the third working fluid channel and the inlet of the first working fluid channel.

[0009] The evaporator has a fourth working fluid channel and a second medium channel. The fourth working fluid channel is used for the second refrigerant to flow through and absorb heat, and the second medium channel is used for the air conditioning water to flow through and release heat. A second compressor is connected between the outlet of the fourth working fluid channel and the inlet of the second working fluid channel, and a second expansion valve is connected between the outlet of the second working fluid channel and the inlet of the fourth working fluid channel.

[0010] According to the present invention, a cascade heat pump tri-generation unit has at least the following beneficial effects:

[0011] By incorporating a fourth working fluid channel and a second medium channel within the evaporator, the second refrigerant, which is in a low-temperature, low-pressure liquid state, absorbs heat and evaporates into a low-temperature, low-pressure gaseous state as it flows through the fourth working fluid channel. Consequently, as the air conditioning water flows through the second medium channel, the heat within the air conditioning water is absorbed by the second refrigerant, causing the temperature of the air conditioning water to drop and resulting in low-temperature water. Compared to the second refrigerant directly absorbing heat from the air as it flows through the evaporator (i.e., directly diffusing the cooling capacity generated by the second refrigerant to the outside), this embodiment utilizes the cooling capacity generated by the second refrigerant as it flows through the evaporator to cool the air conditioning water, thus obtaining low-temperature water and further improving energy efficiency.

[0012] In one optional embodiment, a second condenser is provided between the outlet of the second working fluid channel and the second expansion valve. The second condenser is provided with a fifth working fluid channel and a third medium channel. The fifth working fluid channel is used for the second refrigerant to flow through and release heat, and the third medium channel is used for domestic water to flow through and absorb heat.

[0013] In one optional embodiment, the inlet of the third medium channel and the outlet of the fifth working fluid channel are located at the same end of the second condenser away from the composite heat exchanger; the outlet of the three medium channels and the inlet of the fifth working fluid channel are located at the same end of the second condenser facing the composite heat exchanger.

[0014] In one optional embodiment, the inlet of the first working fluid channel and the outlet of the second working fluid channel are located at a first end of the composite heat exchanger along its length; the outlet of the first working fluid channel and the inlet of the second working fluid channel are located at a second end of the composite heat exchanger along its length.

[0015] In one optional embodiment, the inlet of the third working fluid channel and the outlet of the first medium channel are located at the third end of the first condenser along its length; the outlet of the third working fluid channel and the inlet of the first medium channel are located at the fourth end of the first condenser along its length.

[0016] In one optional embodiment, the inlet of the fourth working fluid channel and the outlet of the second medium channel are located at the fifth end of the evaporator along its length; the outlet of the fourth working fluid channel and the inlet of the second medium channel are located at the sixth end of the evaporator along its length.

[0017] In one optional embodiment, the second expansion valve is configured as an adjustable-opening valve, having a first throttling state with partially open opening and a first fully open, fully conductive state; a first heat exchanger is connected to the second expansion valve and the evaporator via a pipe, the first heat exchanger having a sixth working fluid channel for the flow of the second refrigerant; an adjustable-opening third expansion valve is connected between the outlet of the sixth working fluid channel and the inlet of the fourth working fluid channel, the third expansion valve having a second throttling state with partially open opening and a second fully open, fully conductive state; when the second expansion valve is in the first fully conductive state and the third expansion valve is in the second throttling state, the second refrigerant flowing through the sixth working fluid channel releases heat; an air supply assembly is provided on one side of the evaporator, the air supply assembly for sequentially flowing air through the surfaces of the first heat exchanger and the evaporator.

[0018] In one alternative implementation, the air supply assembly includes a fan.

[0019] In one alternative implementation, the first heat exchanger is configured as a finned heat exchanger.

[0020] In one alternative implementation, the first condenser is configured as a plate condenser. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a traditional cascade high-temperature heat pump system.

[0023] Figure 2 This is a schematic diagram of the structure of the first embodiment of the present utility model;

[0024] Figure 3 This is a schematic diagram of the structure of the second embodiment of the present utility model;

[0025] Figure 4 for Figure 3 A schematic diagram illustrating the defrosting principle.

[0026] Explanation of reference numerals in the attached figures:

[0027] 100 - Composite heat exchanger, 200 - First condenser, 210 - First compressor, 220 - First expansion valve, 300 - Evaporator, 310 - Second compressor, 320 - Second expansion valve, 400 - Second condenser, 500 - First heat exchanger, 510 - Third expansion valve, 520 - Fan, 600 - High-temperature industrial water tank, 700 - Air conditioning water tank, 800 - High-temperature domestic water tank. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] In the description of this embodiment, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this embodiment and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this embodiment. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] In the description of this embodiment, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment according to the specific circumstances.

[0031] The following is combined with Figures 2 to 4 The following describes embodiments of the present invention.

[0032] like Figure 2 As shown, according to an embodiment of this utility model, a cascade heat pump tri-generation unit is provided, including a composite heat exchanger 100, a first condenser 200, and an evaporator 300. The composite heat exchanger 100 has a first working fluid channel and a second working fluid channel. The first working fluid channel is used for the first refrigerant to flow through and absorb heat, and the second working fluid channel is used for the second refrigerant to flow through and release heat. The first condenser 200 has a third working fluid channel and a first medium channel. The third working fluid channel is used for the first refrigerant to flow through and release heat, and the first medium channel is used for industrial water to flow through and absorb heat. The first working fluid channel... A first compressor 210 is connected between the outlet of the third working fluid channel and the inlet of the third working fluid channel, and a first expansion valve 220 is connected between the outlet of the third working fluid channel and the inlet of the first working fluid channel; a fourth working fluid channel and a second medium channel are provided inside the evaporator 300, the fourth working fluid channel is used for the second refrigerant to flow through and absorb heat, and the second medium channel is used for the air conditioning water to flow through and release heat; a second compressor 310 is connected between the outlet of the fourth working fluid channel and the inlet of the second working fluid channel, and a second expansion valve 320 is connected between the outlet of the second working fluid channel and the inlet of the fourth working fluid channel.

[0033] This embodiment of the cascade heat pump tri-generation unit incorporates a fourth working fluid channel and a second medium channel within the evaporator 300. Because the second refrigerant, in a low-temperature, low-pressure liquid state, absorbs heat and evaporates into a low-temperature, low-pressure gaseous state as it flows through the fourth working fluid channel of the evaporator 300, thus generating cooling, the heat in the air conditioning water is absorbed by the second refrigerant as it flows through the second medium channel, resulting in a drop in water temperature and the production of low-temperature water. Compared to the second refrigerant directly absorbing heat from the air as it flows through the evaporator 300 (i.e., directly diffusing the cooling capacity generated by the second refrigerant to the outside), this embodiment utilizes the cooling capacity generated by the second refrigerant as it flows through the evaporator 300 to cool the air conditioning water, thereby further improving energy efficiency.

[0034] In this embodiment, during operation in heating mode, the second refrigerant, initially in a low-temperature, low-pressure liquid state, first flows through the fourth working fluid channel, absorbing heat from the air conditioning water flowing through the second medium channel to form a low-temperature, low-pressure gaseous state, thus cooling the air conditioning water to form low-temperature water. Subsequently, the second refrigerant, still in a low-temperature, low-pressure gaseous state, is compressed into a high-temperature, high-pressure gaseous state by the second compressor 310. It then flows through the second working fluid channel of the composite heat exchanger 100, releasing heat and becoming a high-temperature, high-pressure liquid state. It then passes through the second expansion valve 320, where its pressure is reduced, becoming a low-temperature, low-pressure liquid state again, before re-entering the fourth working fluid channel of the evaporator 300 for circulation. Simultaneously, the first refrigerant, still in a low-temperature, low-pressure liquid state, flows through the first working fluid channel of the composite heat exchanger 100. The first working medium channel absorbs the heat released by the second refrigerant and evaporates into a low-temperature, low-pressure gaseous state. It is then compressed into a high-temperature, high-pressure gaseous state by the first compressor 210, and then flows through the third working medium channel to release heat and become a high-temperature, high-pressure liquid state. This allows the industrial water flowing through the first medium channel of the first condenser 200 to absorb the heat released by the first refrigerant and become high-temperature industrial water. Subsequently, the first refrigerant, which is in a high-temperature, high-pressure liquid state, is throttled and depressurized by the first expansion valve 220 to become a low-temperature, low-pressure liquid state, and then re-enters the first working medium channel of the composite heat exchanger 100 for circulation. This achieves the goal of both using the heating capacity to heat industrial water to obtain high-temperature industrial water and using the cooling capacity to cool air conditioning water to obtain low-temperature water, thereby improving energy efficiency.

[0035] It should be noted that, relative to, Figure 1 Traditional cascade high-temperature heat pump systems only utilize heating capacity to heat industrial water to obtain high-temperature industrial water; the cascade heat pump tri-generation unit in this embodiment can not only utilize heating capacity to heat industrial water to obtain high-temperature industrial water, but also utilize cooling capacity to cool air conditioning water to obtain low-temperature water, thus improving energy efficiency.

[0036] It is understandable that in the circulation loop formed by the sequential connection of the composite heat exchanger 100, the first compressor 210, the first condenser 200, and the first expansion valve 220, the composite heat exchanger 100 plays a role similar to an "evaporator"; in the circulation loop formed by the sequential connection of the composite heat exchanger 100, the second expansion valve 320, the evaporator 300, and the second compressor 310, the composite heat exchanger 100 plays a role similar to a "condenser".

[0037] In specific applications, the high-temperature industrial water generated in this embodiment can be used in production processes such as coating ovens and food processing.

[0038] In specific applications, a high-temperature industrial water tank 600 is connected between the inlet and outlet of the first medium channel to store the produced high-temperature industrial water.

[0039] In specific applications, an air conditioning water tank 700 is connected between the inlet and outlet of the second medium channel to store the produced low-temperature air conditioning water.

[0040] like Figure 2 As shown, in some embodiments, a second condenser 400 is connected between the outlet of the second working fluid channel and the second expansion valve 320. The second condenser 400 contains a fifth working fluid channel and a third medium channel. The fifth working fluid channel is used for the second refrigerant to flow through and release heat, while the third medium channel is used for domestic water to flow through and absorb heat. This arrangement ensures that the second refrigerant, in its high-temperature, high-pressure liquid state, first flows through the fifth working fluid channel of the second condenser 400 to release heat before passing through the second expansion valve 320. This allows the domestic water flowing through the third medium channel to absorb the heat released by the second refrigerant and form hot water. This achieves the ability to heat industrial water using its heating capacity to obtain high-temperature industrial water, cool air conditioning water using its cooling capacity to obtain low-temperature water, and heat domestic water using the heating capacity of the high-temperature, high-pressure liquid second refrigerant to form hot water, thus further improving energy efficiency.

[0041] In practical applications, a high-temperature domestic water tank 800 is connected between the inlet and outlet of the third medium channel to store domestic water heated to hot water.

[0042] In some embodiments, the inlet of the third medium channel and the outlet of the fifth working fluid channel are located at the same end of the second condenser 400 away from the composite heat exchanger 100; the outlet of the three medium channels and the inlet of the fifth working fluid channel are located at the same end of the second condenser 400 facing the composite heat exchanger 100. This arrangement ensures that the flow direction of domestic water in the third medium channel is opposite to the flow direction of the second refrigerant in the fifth working fluid channel. The counter-flowing domestic water and the second refrigerant in a high-temperature, high-pressure liquid state can improve heat exchange efficiency. Simultaneously, the counter-current heat exchange also ensures that the temperature of the domestic water at the outlet of the fifth working fluid channel is higher than the temperature of the second refrigerant at the outlet of the third medium channel. This ensures that even if the temperature of the high-temperature, high-pressure liquid second refrigerant is low, the domestic water temperature can still be effectively increased when the amount of the high-temperature, high-pressure liquid second refrigerant is sufficiently large.

[0043] In some embodiments, the inlet of the first working fluid channel and the outlet of the second working fluid channel are located at the first end of the composite heat exchanger 100 along its length; the outlet of the first working fluid channel and the inlet of the second working fluid channel are located at the second end of the composite heat exchanger 100 along its length. This arrangement ensures that the flow direction of the first refrigerant in the low-temperature, low-pressure liquid state within the first working fluid channel is opposite to the flow direction of the second refrigerant in the high-temperature, high-pressure gaseous state within the second working fluid channel. The counter-flowing first refrigerant in the low-temperature, low-pressure liquid state and the second refrigerant in the high-temperature, high-pressure gaseous state can improve heat exchange efficiency.

[0044] It should be noted that the two ends of the composite heat exchanger 100 along its length are respectively designated as the first end and the second end. The first refrigerant flows from the inlet end to the outlet end of the first working fluid channel along the length of the composite heat exchanger 100 in the first working fluid channel; the second refrigerant flows from the inlet end to the outlet end of the second working fluid channel along the length of the composite heat exchanger 100 in the second working fluid channel.

[0045] In some embodiments, the inlet of the third working fluid channel and the outlet of the first medium channel are located at the third end of the first condenser 200 along its length; the outlet of the third working fluid channel and the inlet of the first medium channel are located at the fourth end of the first condenser 200 along its length. This arrangement ensures that the flow direction of the first refrigerant in its high-temperature, high-pressure gaseous state within the third working fluid channel is opposite to the flow direction of the industrial water within the first medium channel. This counter-current flow of the high-temperature, high-pressure gaseous first refrigerant and industrial water can improve heat exchange efficiency.

[0046] It should be noted that the first condenser 200 has a third end and a fourth end at its two ends along its length, respectively. The first refrigerant flows from the inlet end to the outlet end of the third working fluid channel along the length of the first condenser 200 in the third working fluid channel. Industrial water flows from the inlet end to the outlet end of the first medium channel along the length of the first condenser 200 in the first medium channel.

[0047] In some embodiments, the inlet of the fourth working fluid channel and the outlet of the second medium channel are located at the fifth end of the evaporator 300 along its length; the outlet of the fourth working fluid channel and the inlet of the second medium channel are located at the sixth end of the evaporator 300 along its length. This arrangement ensures that the flow direction of the second refrigerant in the low-temperature, low-pressure liquid state within the fourth working fluid channel is opposite to the flow direction of the air conditioning water within the second medium channel. This counter-current flow of the low-temperature, low-pressure liquid second refrigerant and air conditioning water can improve heat exchange efficiency.

[0048] It should be noted that the two ends of the evaporator 300 along its length are respectively set as the fifth end and the sixth end. The second refrigerant flows from the inlet end to the outlet end of the fourth working fluid channel along the length of the evaporator 300 in the fourth working fluid channel. The air conditioning water flows from the inlet end to the outlet end of the second medium channel along the length of the evaporator 300 in the second medium channel.

[0049] Considering such Figure 1 Traditional cascade high-temperature heat pump systems, after prolonged use, experience frost formation on the surface of the third heat exchanger (03) as the second refrigerant absorbs heat and evaporates into a low-temperature, low-pressure gaseous state. This frost layer, reaching a certain thickness, affects the heat exchange capacity of the third heat exchanger. Therefore, to ensure normal operation, defrosting is necessary to remove the frost and restore normal operation. Traditional defrosting methods involve switching the first four-way valve (05) and the second four-way valve (07) to change the flow direction of the first and second refrigerants. This allows the high-temperature, high-pressure gaseous second refrigerant to flow through the third heat exchanger (03), releasing heat and melting the frost. However, this method requires stopping the heating mode for industrial water and switching back to heating mode after defrosting, affecting continuous heating and increasing energy consumption. To address these technical issues, a new method is needed. Figure 3 and Figure 4As shown, in some embodiments, the second expansion valve 320 is configured as an adjustable valve, having a first throttling state with partially open opening and a first fully open, fully conductive state. A first heat exchanger 500 is connected to the second expansion valve 320 and the evaporator 300 via a pipe. A sixth working fluid channel is provided within the first heat exchanger 500 for the flow of the second refrigerant. A third expansion valve 510 with adjustable opening is connected between the outlet of the sixth working fluid channel and the inlet of the fourth working fluid channel. The third expansion valve 510 has a second throttling state with partially open opening and a second fully open, fully conductive state. When the second expansion valve 320 is in the first fully conductive state and the third expansion valve 510 is in the second throttling state, the second refrigerant flowing through the sixth working fluid channel releases heat. An air supply assembly is provided on one side of the evaporator 300, which sequentially directs airflow across the surfaces of the first heat exchanger 500 and the evaporator 300.

[0050] In this embodiment, during operation in heating mode without defrosting, the second expansion valve 320 is switched to the first throttling state, and the third expansion valve 510 is switched to the second fully open state. First, the second refrigerant, in a low-temperature, low-pressure liquid state, flows through the fourth working fluid channel, absorbing heat from the air conditioning water flowing through the second medium channel to form a low-temperature, low-pressure gaseous state, thus cooling the air conditioning water to form low-temperature water. Then, the second refrigerant, still in a low-temperature, low-pressure gaseous state, is compressed into a high-temperature, high-pressure gaseous state by the second compressor 310. It then flows through the second working fluid channel of the composite heat exchanger 100, releasing heat and becoming a high-temperature, high-pressure liquid state. Next, it is throttled and depressurized by the second expansion valve 320 in the first throttling state, becoming a low-temperature, low-pressure liquid state. It then flows through the sixth working fluid channel of the first heat exchanger 500, absorbing heat and evaporating, before flowing back into the evaporator through the third expansion valve 510 in the second fully open state. The first refrigerant, in a low-temperature, low-pressure liquid state, circulates through the fourth working fluid channel of the heat exchanger 300. Simultaneously, the first refrigerant, in a low-temperature, low-pressure liquid state, flows through the first working fluid channel of the composite heat exchanger 100, absorbs the heat released by the second refrigerant, evaporates into a low-temperature, low-pressure gaseous state, and is then compressed into a high-temperature, high-pressure gaseous state by the first compressor 210. It then flows through the third working fluid channel, releases heat, and becomes a high-temperature, high-pressure liquid state. This causes the industrial water flowing through the first medium channel of the first condenser 200 to absorb the heat released by the first refrigerant and become high-temperature industrial water. Subsequently, the first refrigerant, in a high-temperature, high-pressure liquid state, is throttled and depressurized by the first expansion valve 220 to become a low-temperature, low-pressure liquid state, and then re-enters the first working fluid channel of the composite heat exchanger 100 for circulation. This achieves both the ability to use the heating capacity to heat industrial water to obtain high-temperature industrial water and the ability to use the cooling capacity to cool air conditioning water to obtain low-temperature water, thereby improving energy efficiency.

[0051] When it is necessary to remove the frost layer adhering to the surfaces of the first heat exchanger 500 and the evaporator 300, the second expansion valve 320 is switched to the first fully open state, and the third expansion valve 510 is switched to the second throttling state. First, the second refrigerant, which is in a low-temperature, low-pressure liquid state, flows through the fourth working fluid channel and absorbs the heat of the air conditioning water flowing through the second medium channel to form a low-temperature, low-pressure gaseous state, thereby cooling the air conditioning water to form low-temperature water. Then, the second refrigerant, which is in a low-temperature, low-pressure gaseous state, is compressed into a high-temperature, high-pressure gaseous state by the second compressor 310, and then flows through the second working fluid channel of the composite heat exchanger 100 to release heat and become high-temperature gaseous. The high-pressure liquid refrigerant, after passing through the second expansion valve 320 in its first fully open state, remains at a high temperature and pressure. It then flows through the sixth working fluid channel of the first heat exchanger 500, releasing heat and raising the surface temperature of the first heat exchanger 500 to remove the frost layer adhering to its surface. Furthermore, under the action of the air supply assembly, airflow passes over the surface of the first heat exchanger 500, absorbing heat and forming hot air, which is then blown onto the surface of the evaporator 300, melting the frost layer on the evaporator 300 surface. Subsequently, the high-temperature, high-pressure liquid refrigerant is throttled and depressurized through the third expansion valve 510 in its second throttling state, becoming a low-temperature, low-pressure liquid. The refrigerant then re-enters the fourth working fluid channel of the evaporator 300 for circulation; simultaneously, the first refrigerant, in a low-temperature, low-pressure liquid state, flows through the first working fluid channel of the composite heat exchanger 100, absorbing the heat released by the second refrigerant and evaporating into a low-temperature, low-pressure gaseous state. It is then compressed into a high-temperature, high-pressure gaseous state by the first compressor 210, and then flows through the third working fluid channel, releasing heat and becoming a high-temperature, high-pressure liquid state. This causes the industrial water flowing through the first medium channel of the first condenser 200 to absorb the heat released by the first refrigerant and become high-temperature industrial water. Subsequently, the first refrigerant, in its high-temperature, high-pressure liquid state, is throttled and depressurized by the first expansion valve 220. The liquid is converted into a low-temperature, low-pressure liquid state and then re-enters the first working fluid channel of the composite heat exchanger 100 for circulation; this removes the frost layer adhering to the surface of the first heat exchanger 500 and evaporator 300 while preparing high-temperature industrial water and low-temperature air conditioning water normally; this allows for seamless switching between heating mode and "heating + defrosting" mode in this embodiment without the need for a four-way valve to switch the direction, simplifying control, improving reliability, and featuring a simple and compact structure, small equipment size, and small footprint, while ensuring that the defrosting process neither occupies additional time for producing high-temperature industrial water nor affects the water temperature of the high-temperature industrial water.

[0052] Specifically, temperature sensors are provided on the surfaces of the first heat exchanger 500 and the evaporator 300. The temperature sensors are electrically connected to the controller. When the surface temperature of the first heat exchanger 500 and the evaporator 300 is lower than the air dew point for a period of time, that is, when the temperature sensor detects that the surface temperature of the first heat exchanger 500 and the evaporator 300 is lower than the set value, it transmits a signal to the controller. The controller adjusts the opening of the second expansion valve 320 and the third expansion valve 510 to switch the heating mode to the "heating + defrosting" mode.

[0053] In specific applications, the air supply component includes the fan 520.

[0054] Specifically, the first heat exchanger 500 is configured as a finned heat exchanger, which can complete evaporation or condensation without relying on a secondary heat exchange loop, significantly reducing complexity.

[0055] Specifically, the first condenser 200 is configured as a plate condenser to improve the heat exchange effect when industrial water and the second refrigerant flow through the first condenser 200.

[0056] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A cascade heat pump tri-generation unit, characterized in that, include: The composite heat exchanger (100) is provided with a first working fluid channel and a second working fluid channel. The first working fluid channel is used for the first refrigerant to flow through and absorb heat, and the second working fluid channel is used for the second refrigerant to flow through and release heat. The first condenser (200) is provided with a third working fluid channel and a first medium channel. The third working fluid channel is used for the first refrigerant to flow through and release heat, and the first medium channel is used for the industrial water to flow through and absorb heat. A first compressor (210) is provided between the outlet of the first working fluid channel and the inlet of the third working fluid channel, and a first expansion valve (220) is provided between the outlet of the third working fluid channel and the inlet of the first working fluid channel. An evaporator (300) is provided with a fourth working fluid channel and a second medium channel. The fourth working fluid channel is used for the second refrigerant to flow through and absorb heat, and the second medium channel is used for the air conditioning water to flow through and release heat. A second compressor (310) is provided between the outlet of the fourth working fluid channel and the inlet of the second working fluid channel, and a second expansion valve (320) is provided between the outlet of the second working fluid channel and the inlet of the fourth working fluid channel.

2. The cascade heat pump tri-generation unit according to claim 1, characterized in that, A second condenser (400) is provided between the outlet of the second working fluid channel and the second expansion valve (320). The second condenser (400) is provided with a fifth working fluid channel and a third medium channel. The fifth working fluid channel is used for the second refrigerant to flow through and release heat, and the third medium channel is used for domestic water to flow through and absorb heat.

3. A cascade heat pump tri-generation unit according to claim 2, characterized in that, The inlet of the third medium channel and the outlet of the fifth working medium channel are located at the same end of the second condenser (400) away from the composite heat exchanger (100); the outlet of the three medium channels and the inlet of the fifth working medium channel are located at the same end of the second condenser (400) facing the composite heat exchanger (100).

4. A cascade heat pump tri-generation unit according to claim 1, characterized in that, The inlet of the first working fluid channel and the outlet of the second working fluid channel are located at the first end of the composite heat exchanger (100) along its length direction; the outlet of the first working fluid channel and the inlet of the second working fluid channel are located at the second end of the composite heat exchanger (100) along its length direction.

5. A cascade heat pump tri-generation unit according to claim 1, characterized in that, The inlet of the third working fluid channel and the outlet of the first medium channel are located at the third end of the first condenser (200) along its length; the outlet of the third working fluid channel and the inlet of the first medium channel are located at the fourth end of the first condenser (200) along its length.

6. A cascade heat pump tri-generation unit according to claim 1, characterized in that, The inlet of the fourth working fluid channel and the outlet of the second medium channel are located at the fifth end of the evaporator (300) along its length; the outlet of the fourth working fluid channel and the inlet of the second medium channel are located at the sixth end of the evaporator (300) along its length.

7. A cascade heat pump tri-generation unit according to any one of claims 1 to 6, characterized in that, The second expansion valve (320) is configured as an adjustable valve, having a first throttling state with partial opening and a first fully open, fully conductive state. A first heat exchanger (500) is connected to the evaporator (300) via a pipe. A sixth working fluid channel is provided within the first heat exchanger (500) for the flow of the second refrigerant. An adjustable opening is provided between the outlet of the sixth working fluid channel and the inlet of the fourth working fluid channel. The third expansion valve (510) is adjusted, and the third expansion valve (510) has a second throttling state with a partially open opening and a second fully open state with a fully open opening; when the second expansion valve (320) is in the first fully open state and the third expansion valve (510) is in the second throttling state, the second refrigerant flowing through the sixth working fluid channel releases heat; an air supply assembly is provided on one side of the evaporator (300), and the air supply assembly is used to sequentially flow air through the surfaces of the first heat exchanger (500) and the evaporator (300).

8. A cascade heat pump tri-generation unit according to claim 7, characterized in that, The air supply assembly includes a fan (520).

9. A cascade heat pump tri-generation unit according to claim 7, characterized in that, The first heat exchanger (500) is configured as a finned heat exchanger.

10. A cascade heat pump tri-generation unit according to claim 1, characterized in that, The first condenser (200) is configured as a plate condenser.

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