Phase change direct heating type bathroom heat recovery heat pump water heater and AI intelligent control method

Abstract

The application discloses a phase change direct heating type bathroom heat recovery heat pump water heater and an AI intelligent control method, and belongs to the technical field of household bathroom phase change heat pump water heaters; the water heater comprises a phase change heat pump host, an evaporation heat exchange module and a double heat recovery device; the phase change heat pump host is an ultra-thin wall hanging structure, and is internally provided with a compressor, a four-way valve, a phase change heat storage water tank, a plate heat exchanger, a throttle valve and a flow regulating valve 1; the evaporation heat exchange module is installed at a bathroom air outlet, and is internally provided with a heating mode and a ventilation mode; the double heat recovery device is a two-layer structure, the upper layer is a water side heat recovery device, the lower layer is a fluorine side heat recovery device, and is used for reducing the temperature of waste water to a near freezing state of 3 DEG C to 5 DEG C; the application also provides a corresponding AI intelligent control method, the environmental temperature curve and user water use habits are obtained through networking and big data analysis, intelligent start and stop and variable frequency control are realized, and the water heater has the advantages of high heat recovery efficiency, instant heating, convenient installation and significant energy saving.

Description

Technical Field

[0001] This invention relates to the field of phase change heat pump water heater technology for household bathrooms, and more specifically, to a phase change direct heating bathroom heat recovery heat pump water heater and an AI intelligent control method. Background Technology

[0002] Currently, domestic hot water supply mainly uses electric or gas water heaters, which have high energy consumption. Moreover, both electricity and gas are high-grade energy sources, and directly using them to produce domestic hot water results in low energy utilization efficiency. Although air source heat pump water heaters have higher energy efficiency, they are bulky and inconvenient to install in ordinary family bathrooms. At the same time, their water tanks are usually far away from the water point, resulting in long hot water delivery distances, slow water output, and long waiting times for users. To solve the problem of slow water output, some solutions use the addition of a return water system. However, the return water system not only increases heat loss in the pipeline but also requires additional energy consumption from the water pump, further reducing the overall energy efficiency of the system.

[0003] In addition, the wastewater generated during the bathing process is usually around 35°C and is discharged directly after bathing, resulting in a large waste of low-grade heat energy. According to statistics, the annual discharge of urban bathing wastewater in China is about 12 billion cubic meters. The heat contained in this wastewater has the value of large-scale recovery. Although there are some waste heat recovery solutions in the existing technology, they are mostly limited to single water-to-water heat exchange or refrigerant-to-water heat exchange, with limited heat recovery efficiency and unable to make full use of the heat in the wastewater.

[0004] Therefore, how to efficiently recover low-grade waste heat from bathing wastewater and achieve rapid hot water output while ensuring the miniaturization of heat pump water heaters and their suitability for bathroom installation is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] To overcome the problems existing in the above technologies, this invention provides a phase change direct heating bathroom heat recovery heat pump water heater, which consists of three modules: a phase change heat pump main unit, a dual heat recovery unit, and an evaporative heat exchange module; specifically including: The phase change heat pump unit features an ultra-thin wall-mounted design, installed in indoor bathrooms or balconies, similar to the installation method of traditional electric or gas water heaters. The internal structure of the phase change heat pump unit includes a compressor, a four-way valve, a phase change hot water storage tank, a plate heat exchanger, a throttling valve, and a flow regulating valve 1. Following the reverse Carnot cycle principle, the phase change heat pump unit absorbs heat from the evaporative heat exchange module and the dual heat recovery unit, and transfers this heat to the phase change hot water storage tank and plate heat exchanger through refrigerant circulation. The external components of the phase change heat pump unit are connected to the evaporative heat exchange module and the dual heat recovery unit via refrigerant pipes for refrigerant heating circulation. Simultaneously, the external components are connected to the dual heat recovery unit via water pipes for preheating and recovering cold water, and connecting hot water to the user's hot water pipe. Specifically, the phase change heat pump unit also includes a heat pump system installation area, refrigerant system piping, an electrical control box, a wired controller, and an insulation shell. The heat pump system installation area is located in the upper part of the phase change heat pump unit and is used to install the compressor, The system includes a plate heat exchanger, an electrical control box, various valves, and bends. The refrigerant system connector connects the phase change heat pump unit to the evaporative heat exchange module and the dual heat recovery unit, enabling the refrigerant to circulate heat. In hot water mode, the plate heat exchanger directly heats the inlet water, which has been preheated by the initial water recovery in the dual heat recovery unit, and delivers it to the user's hot water point after reaching the target outlet temperature. The electrical control box collects parameters such as ambient temperature, plate heat exchanger condensing temperature, upper and lower water tank temperatures, flow meter and flow regulating valve parameters, as well as the evaporation temperature 1 of the evaporative heat exchange module and the evaporation temperature 2 of the dual heat recovery unit. Based on the collected parameters, it adjusts the compressor operating frequency, fan speed, throttle valve opening, and the opening of each flow regulating valve. The wired controller provides feedback and operates the overall operating status, target water temperature, operating mode, and automatic operation phase of the phase change direct-heating bathroom heat recovery heat pump water heater. The insulation shell provides structural protection and support for the phase change heat pump unit and also serves as sound insulation and heat preservation.

[0006] The phase change hot water storage tank stores the heat provided by the heat pump in the phase change material. It incorporates a water-side heat exchange coil and a refrigerant-side heat exchange microchannel. The water-side heat exchange coil is a single copper tube, arranged in an S-shape from top to bottom, and flows counter-currently with the refrigerant-side heat exchange microchannel. The refrigerant-side heat exchange microchannel heats the phase change material in the storage tank with the heat provided by the phase change heat pump. The refrigerant-side heat exchange microchannel is divided into three groups of parallel microchannels, with the number of parallel microchannels decreasing progressively in each group. The heating method is as follows: first, four parallel microchannels form the upper part of the first group of heating from left to right; then, three parallel microchannels form the middle part of the second group of heating from right to left; and finally, two parallel microchannels form the lower part of the third group of heating from left to right. The phase change hot water storage tank is also equipped with fluorine inlet, fluorine outlet, upper temperature sensor, lower temperature sensor, hot water inlet, and hot water outlet. A flow regulating valve 3 is installed on the hot water inlet pipe to control the water flow rate through the water-side heat exchange coil of the phase change hot water storage tank.

[0007] The evaporative heat exchange module is installed at the bathroom exhaust vent and has a built-in ventilation recognition mode, including Mode 1 and Mode 2. Mode 1 is the heating mode, which activates when the heat pump is heating, absorbing heat through the evaporative heat exchanger and exhausting cool air outdoors. Mode 2 is the ventilation mode, which activates the fan via a wireless switch when the heat pump is not heating but bathroom ventilation is required. In this mode, only the fan is activated, while the flow regulating valve 2 is closed. The flow regulating valve 2 is located on the refrigerant inlet pipe of the evaporative heat exchange module. Specifically, the evaporative heat exchange module includes an evaporative heat exchanger and a fan. The system includes a fan blade and a flow regulating valve 2. The flow regulating valve 2 is installed on the refrigerant inlet pipe of the evaporative heat exchange module to control the refrigerant flow rate into the evaporative heat exchange module. The evaporative heat exchange module is used in conjunction with a wireless switch: in the phase change heat pump main unit heating mode, regardless of whether the wireless switch is turned on or off, the fan automatically adjusts its speed according to the heating demand to absorb heat through the evaporative heat exchanger and exhaust the cold air to the outside; in the heat pump non-heating mode, when the wireless switch is turned on, the fan starts directly for ventilation, but the flow regulating valve 2 is in the closed state.

[0008] The dual heat recovery unit has a two-layer structure: the upper layer is a water-side heat recovery unit, which is formed by a single S-shaped pipe and is used to preheat the inlet water entering the phase change heat pump host before heating it to the target outlet water temperature in the plate heat exchanger or phase change hot water storage tank; the lower layer is a refrigerant-side heat recovery unit, which is composed of a lower layer microchannel heat exchange plate and is used to perform phase change enthalpy increase on the refrigerant entering the phase change heat pump host to improve the refrigerant system circulation efficiency and reduce the water temperature in the lower layer to a near-freezing state of 3°C to 5°C. Specifically, the dual heat recovery unit is also equipped with a tap water inlet, a water-side heat recovery pipe port, a lower layer refrigerant inlet and outlet, and a temperature sensor for detecting the evaporation temperature 2; a flow regulating valve 4 is installed on the cold water supply pipe of the plate heat exchanger of the phase change heat pump host to control the flow rate of cold water entering the plate heat exchanger.

[0009] In addition, this invention also provides an AI intelligent control method for a phase change direct heating bathroom heat recovery heat pump water heater. This method is based on the aforementioned phase change direct heating bathroom heat recovery heat pump water heater and includes the following steps: Step 1: The water heater is powered on and it is determined whether the upper and lower temperatures of the phase change heat storage tank are not less than the user-set temperature T0. If so, the heating system is not started; otherwise, the phase change heat pump host is started for heating. At this time, the ambient temperature curve of the day is obtained online, and it is confirmed whether the future heating period is more than 1 / 3 of the highest temperature period of the ambient temperature curve of the day. If so, it is directly heated to the user-set temperature T0+10℃ for high ambient temperature heat storage. Otherwise, it is heated only to the basic heating temperature T1, where ℃ is degrees Celsius; Step 2: After the water heater determines that the phase change heat storage tank is heating, the compressor frequency is PID-regulated according to the difference between the upper and lower temperatures of the phase change heat storage tank and T0, respectively. The fan speed of the evaporation heat exchange module is regulated according to the difference between the evaporation temperature 1 and the ambient temperature. The throttling valve is regulated according to the system superheat. The flow regulating valve 2 is regulated according to the evaporation temperature 2, controlling the target evaporation temperature of evaporation temperature 2 to be 3℃ to 5℃. During the heat pump heating process, the high-temperature refrigerant, after being compressed and heated by the compressor, is sent to the phase change heat storage tank to heat the phase change material for heat storage. The refrigerant is throttled and then passes through the evaporation heat exchange module. The heat is absorbed by the block and the dual heat recovery module and returned to the compressor for the next round of heat exchange. Step 3: When the upper and lower temperatures of the phase change heat storage tank meet the temperature threshold for shutdown, and when a water flow signal is detected by the flow meter (i.e., when the user starts using hot water), the water heater first opens the flow regulating valve 3, allowing water to flow through the water-side heat exchange coil of the phase change heat storage tank for heating. Meanwhile, the flow regulating valve 1 is fully open, allowing the high-temperature refrigerant to preferentially pass through the plate heat exchanger. When the condensing temperature of the plate heat exchanger is not less than T0 + T2, the flow regulating valve 4 is gradually opened and the flow regulating valve 3 is simultaneously closed until the flow regulating valve 3 is completely closed, allowing the water flow to be completely switched to direct heating through the plate heat exchanger. If the heat pump's heating is insufficient during the process, causing fluctuations in the hot water outlet temperature, the flow regulating valve 3 will be dynamically supplemented with heat based on the difference between the real-time outlet temperature and the target temperature. Step 4: Intelligent operation of the water heater for heating the phase change hot water storage tank: After the phase change hot water storage tank stops heating for the first time, when a reading is detected on the flow meter, the 24-hour flow curve with Z as a recording period is started to be recorded. At the same time, data is recorded and processed using three factors: Factor 1 is the normal working hours; Factor 2 is the weekend and holiday periods; Factor 3 is the four seasonal periods. The processing yields eight daily water consumption curves, including daily water consumption curves for the normal working hours and daily water consumption curves for non-working hours under different seasons.After completing the daily water usage curve for the first Z-cycle, a real-time linkage mechanism is activated. The ambient temperature obtained via the internet is used as factor 4, and the heating capacity, which varies with the ambient temperature, is used as factor 5 to intelligently predict the user's hot water demand. The prediction calculation big data model integrates five factors (factors 1 to 5), where factors 1 to 3 are demand factors, and factors 4 and 5 are supply factors. Based on the predicted demand model, a corresponding heating capacity calculation model is generated to determine an appropriate operating strategy for different time periods, thereby determining the combination of water heater start / stop and frequency converter operation.

[0010] Furthermore, the user-set temperature T0 is 55℃; the basic heating temperature T1 is 45℃; the T2 is 15℃; and the cycle Z is 20 days.

[0011] Furthermore, when the heat pump water heater is not heating and bathroom ventilation is required, the fan of the evaporative heat exchange module can be turned on by a wireless switch. At this time, the flow regulating valve 2 is in the closed state, realizing a ventilation mode that only ventilates without heat exchange.

[0012] The beneficial effects of this invention are as follows: This invention provides a phase change direct heating bathroom heat recovery heat pump water heater. This system has the following advantages: 1. By setting up a dual heat recovery unit with water-side heat recovery on the upper layer and refrigerant-side heat recovery on the lower layer, two-stage heat recovery is achieved for bathing wastewater, reducing the wastewater temperature to a near-freezing state of 3°C to 5°C. Combined with the absorption of heat from the air by the evaporative heat exchange module, the energy consumption of the water heater is reduced to less than one-fifth of that of traditional water heaters, significantly improving heat recovery efficiency and energy saving effect; 2. Direct heating is achieved by setting up a plate heat exchanger, with priority given to heating from the phase change hot water storage tank during the initial use of hot water. Once the condensing temperature of the plate heat exchanger reaches the target, the flow regulating valve switches to a different temperature. 1. Direct heating via plate heat exchanger enables instant hot water, solving the problems of slow water output and increased energy consumption associated with traditional heat pump water heaters requiring additional recirculation systems; 2. The phase change heat pump unit of this invention adopts an ultra-thin wall-mounted structure design, with the evaporative heat exchange module integrated into the bathroom exhaust vent, without occupying additional indoor space, thus solving the problem of traditional air source heat pump water heaters being too bulky and inconvenient for installation in ordinary family bathrooms; 3. This invention uses AI intelligent control to obtain the ambient temperature curve online and select the period with the highest temperature on the ambient temperature curve for heat storage. At the same time, based on big data analysis of user water usage habits, it predicts hot water demand, intelligently generates operating strategies, and achieves adaptive optimization control, further reducing operating energy consumption. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the module structure of a phase change direct heating bathroom heat recovery heat pump water heater according to the present invention.

[0014] Figure 2 This is a schematic diagram of the phase change heat pump main unit.

[0015] Figure 3 This is a schematic diagram of the internal structure of a phase change hot water storage tank.

[0016] Figure 4 This is a schematic diagram illustrating the working principle of a phase change direct heating bathroom heat recovery heat pump water heater.

[0017] in, Figure 1 6 is the phase change heat pump main unit, 7 is the evaporation heat exchange module, 8 is the dual heat recovery unit, 9 is the fluorine connection pipe, 10 is the water connection pipe, and 11 is the exhaust vent. Figure 2 12 is the phase change hot water storage tank, 13 is the plate heat exchanger, 14 is the heat pump system installation area, 15 is the refrigerant system connection pipe, 16 is the electrical control box, 17 is the wired controller, 18 is the insulation shell, and 19 is the inlet and outlet water pipes. Figure 3 20 is the water-side heat exchange coil, 21 is the hot water inlet, 22 is the hot water outlet, 23 is the flow regulating valve 3, 24 is the refrigerant inlet, 25 is the refrigerant outlet, 26 is the refrigerant-side heat exchange microchannel, 27 is the upper temperature, 28 is the lower temperature, 29 is 4 parallel microchannels, 30 is 3 parallel microchannels, and 31 is 2 parallel microchannels. Detailed Implementation

[0018] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0019] like Figure 1 The diagram shows a phase change direct heating bathroom heat pump water heater module according to the present invention. The diagram illustrates that the heat pump water heater consists of three modules: a phase change heat pump main unit 6, an evaporative heat exchange module 7, and a dual heat recovery unit 8. The phase change heat pump main unit 6 is connected to the evaporative heat exchange module 7 via a refrigerant pipe 9, and the evaporative heat exchange module 7 is connected to the dual heat recovery unit 8 via a refrigerant pipe 9. The phase change heat pump main unit 6 and the dual heat recovery unit 8 are also connected via a water pipe 10. The evaporative heat exchange module 7 is installed at the bathroom exhaust vent 11, through which the cold air generated after absorbing heat from the evaporative heat exchange module 7 is discharged outdoors. The dual heat recovery unit 8 is installed on the bathroom floor or at the drain location. When a person showers above the dual heat recovery unit 8, the wastewater generated during showering flows directly through the surface of the dual heat recovery unit 8, achieving heat recovery.

[0020] like Figure 2The diagram shows the structure of the phase change heat pump main unit of the present invention. The phase change heat pump main unit 6 has an ultra-thin wall-mounted structure design and is installed in the indoor bathroom or balcony area. The installation method is the same as that of traditional electric water heaters or gas water heaters. It can directly replace the existing water heater without the need for large-scale modification of the installation environment. The phase change heat pump main unit 6 includes a heat pump system installation area 14, a refrigerant system connection pipe 15, an electrical control box 16, a wired controller 17, an insulation shell 18, a phase change hot water storage tank 12, and a plate heat exchanger 13. The heat pump system installation area 14 is located in the upper part of the phase change heat pump main unit 6, which facilitates installation and maintenance. A refrigerant system connection pipe 15 is arranged on the outer left side of the heat pump system installation area 14. The refrigerant system connection pipe 15 includes two independent pipes: a refrigerant inlet pipe and a refrigerant outlet pipe. The refrigerant inlet pipe is used to transport the low-temperature refrigerant after condensation and heat release from the phase change heat pump host 6 to the evaporation heat exchange module 7 and the dual heat recovery unit 8. The refrigerant outlet pipe is used to transport the high-temperature gaseous refrigerant after heat absorption and evaporation from the evaporation heat exchange module 7 and the dual heat recovery unit 8 back to the phase change heat pump host 6. A plate heat exchanger 13 is arranged in the middle of the heat pump system installation area 14, and an electrical control box 16 is arranged on the right side. The compressor and four... The system includes a flow control valve, a throttle valve, and a flow regulating valve 1. These components are connected via pipelines to form a complete refrigerant circulation loop. Below the heat pump system installation area 14 is a phase change hot water storage tank 12. At the bottom left of the phase change hot water storage tank 12 are inlet and outlet pipes 19. Each inlet and outlet pipe 19 has two independent interfaces: an inlet and an outlet. The inlet is used to introduce preheated cold water (after passing through the dual heat recovery unit 8) into the phase change hot water storage tank 12, and the outlet is used to output heated hot water from the phase change hot water storage tank 12 to the user's hot water point. The separate arrangement of the inlet and outlet facilitates external pipeline connections. A wired controller 17 is located at... The lower part of the phase change heat pump unit 6 facilitates user operation and status monitoring. The insulation shell 18 encloses the entire phase change heat pump unit 6, filled with insulation material, providing structural protection, support, sound insulation, and heat preservation, reducing heat loss and improving overall energy efficiency. The refrigerant system connector 15 connects the phase change heat pump unit 6 to the evaporator heat exchange module 7 and the dual heat recovery unit 8, enabling refrigerant heating circulation. The refrigerant flows through the refrigerant system connector 15, transferring heat from the evaporator heat exchange module 7 and the dual heat recovery unit 8 to the phase change heat pump unit 6. The electrical control box 16 collects ambient temperature and plate heat exchanger condensing temperature data. The system collects parameters such as temperature at the top and bottom of the water tank, flow meter and flow regulating valves, as well as the evaporation temperature 1 of the evaporation heat exchange module and the evaporation temperature 2 of the dual heat recovery unit. Based on the collected parameters, it adjusts the compressor operating frequency, fan speed, throttle valve opening and the opening of each flow regulating valve to achieve intelligent operation control of the whole machine. The wired controller 17 is used to provide feedback and operate the overall operating status, target water temperature, operating mode and automatic operation period of the phase change direct heating bathroom heat recovery heat pump water heater. Users can set the outlet water temperature, view the current operating status and select manual or automatic mode through the wired controller 17.

[0021] like Figure 3 The diagram shows the internal structure of the phase change hot water storage tank 12. The phase change hot water storage tank 12 stores the heat provided by the heat pump within the phase change material, and includes a water-side heat exchange coil 20 and a refrigerant-side heat exchange microchannel 26. The phase change material fills the internal space of the phase change hot water storage tank 12, exhibiting high energy storage density and stable phase change temperature, enabling it to store a large amount of heat even under conditions of minimal temperature fluctuation. The water-side heat exchange coil 20 is a single copper tube, arranged in an S-shape from top to bottom, and flows counter-currently to the refrigerant-side heat exchange microchannel 26. This counter-current heat exchange maximizes the heat exchange temperature difference and improves heat exchange efficiency. The water-side heat exchange coil 20 extends from the lower part of the phase change hot water storage tank 12 towards... The hot water inlet 21 and hot water outlet 22 are both located at the bottom of the phase change hot water storage tank 12, forming a same-side arrangement for easy pipe connection and installation. The hot water inlet 21 is connected to the inlet of the inlet / outlet pipe 19, and the hot water outlet 22 is connected to the outlet of the inlet / outlet pipe 19. A flow regulating valve 3 (marked 23) is installed on the hot water inlet 21 to control the water flow rate through the water-side heat exchange coil 20 of the phase change hot water storage tank 12. By adjusting the opening of the flow regulating valve 3, the rate at which hot water is extracted from the phase change hot water storage tank 12 can be controlled, thereby achieving precise control of the outlet water temperature. The refrigerant-side heat exchange microchannel 26 is used to transfer the phase change heat... The heat provided by the pump unit 6 heats the phase change material in the phase change hot water storage tank 12. The fluorine-side heat exchange microchannels 26 are divided into three groups of parallel microchannels, with the number of parallel microchannels in each group decreasing progressively: first, four parallel microchannels (marked 29) heat the upper part of the phase change hot water storage tank 12 from left to right; then, three parallel microchannels (marked 30) heat the middle part from right to left; and finally, two parallel microchannels (marked 31) heat the lower part from left to right. This progressively decreasing parallel microchannel design ensures that the upper part of the phase change hot water storage tank 12 heats the fastest, followed by the middle part, and the lower part heats the slowest, achieving uniform melting of the phase change material and... The heat is evenly distributed to avoid local overheating or undercooling. The refrigerant inlet 24 and refrigerant outlet 25 are located on the upper left side of the phase change hot water storage tank 12. The high-temperature refrigerant enters the heat exchange microchannel 26 on the refrigerant side through the refrigerant inlet 24, releases heat and condenses, and then flows out through the refrigerant outlet 25 to enter the next cycle. The phase change hot water storage tank 12 is also equipped with an upper temperature sensor 27 and a lower temperature sensor 28, which are respectively located one-quarter of the distance from the upper and lower parts of the phase change hot water storage tank 12 to detect the temperature of the upper and lower parts of the tank. The electrical control box 16 determines the heat storage status of the phase change hot water storage tank 12 based on the detection values ​​of the upper temperature sensor 27 and the lower temperature sensor 28, thereby deciding whether to start or stop heating.

[0022] In the above embodiment, specifically, the evaporative heat exchange module 7 is installed at the bathroom exhaust vent 11, and includes an evaporative heat exchanger, a fan, fan blades, and a flow regulating valve 2; the flow regulating valve 2 is located on the refrigerant inlet pipe of the evaporative heat exchange module 7, and is used to control the refrigerant flow rate entering the evaporative heat exchange module 7. This refrigerant inlet pipe is part of the refrigerant inlet pipe in the refrigerant connector 9; the evaporative heat exchange module 7 has a built-in ventilation recognition mode, including mode 1 and mode 2; mode 1 is the heating mode, which is turned on when the heat pump is heating, and the fan automatically adjusts according to the heating demand. When the fan speed is controlled, the heat is absorbed from the bathroom exhaust air through the evaporative heat exchanger and the cold air is discharged outdoors. At this time, the flow regulating valve 2 is in the open state, and the low-temperature refrigerant enters the evaporative heat exchanger to absorb the heat from the air and then turns into a gaseous state and returns to the compressor. Mode 2 is the ventilation mode. When the heat pump is not heating but the bathroom exhaust air needs to be used, the fan is turned on by the wireless switch. At this time, only the fan is turned on for ventilation, but the flow regulating valve 2 is in the closed state. There is no refrigerant flowing in the evaporative heat exchanger, and no heat absorption is performed. It only plays the role of exhaust and ventilation.

[0023] Specifically, the dual heat recovery unit 8 has a two-layer structure. The upper layer is a water-side heat recovery unit, consisting of a single S-shaped pipe with a tap water inlet and a water-side heat recovery port. It is used to preheat the incoming water entering the phase change heat pump unit 6, and then heat it to the target outlet temperature in the plate heat exchanger 13 or the phase change hot water storage tank 12. The tap water enters the upper water-side heat recovery pipe from the inlet and exchanges heat with the bath wastewater flowing over the surface of the dual heat recovery unit 8 in the S-shaped pipe. After the temperature rises, it enters the phase change heat pump unit 6 through the water connecting pipe 10. The lower layer is a refrigerant-side heat recovery unit, consisting of a lower microchannel heat exchange plate. It has a lower refrigerant inlet and outlet and a temperature sensor for detecting the evaporation temperature 2. It is used to perform phase change enthalpy increase on the refrigerant entering the phase change heat pump unit 6. To improve the energy efficiency of the fluorine system circulation and reduce the water temperature in the lower layer to a near-freezing state of 3°C to 5°C, the heat in the wastewater is fully recovered. The bathing wastewater first flows through the surface of the lower fluorine-side heat recovery, where it exchanges heat with the low-temperature refrigerant in the microchannel, reducing its temperature to 3°C to 5°C. Then it flows through the surface of the upper water-side heat recovery, where it exchanges heat with tap water for a second time, achieving staged heat recovery of wastewater. A flow regulating valve 4 is installed on the cold water supply pipeline of the plate heat exchanger 13 of the phase change heat pump host 6 to control the flow rate of cold water entering the plate heat exchanger 13. In the direct heating mode, the water, after being preheated by the dual heat recovery unit 8, enters the plate heat exchanger 13, exchanges heat with the high-temperature refrigerant, and is heated to the target outlet water temperature before being directly delivered to the user's hot water point.

[0024] The working principle of the present invention will be described in detail below: Figure 4The diagram illustrates the working principle of a phase change direct heating bathroom heat recovery heat pump water heater according to the present invention. In this diagram, after the water heater is powered on, it first performs a heat storage mode judgment. The control box 16 detects the upper and lower temperatures of the phase change hot water storage tank 12 via the upper temperature sensor 27 and the lower temperature sensor 28, determining whether both are not less than the user-set temperature T0, where T0 is the target outlet water temperature set by the user through the wired controller 17, with a default value of 55℃. If both are not less than T0, it indicates that the heat in the phase change hot water storage tank 12 is sufficient to meet the user's water demand, and the heating system is not activated, with the unit in standby mode. If either temperature is less than T0, it indicates that the heat in the phase change hot water storage tank 12 is insufficient, and activation is required. When heating begins, the control box 16 starts the phase change heat pump host 6 to heat the system. Upon startup, the control box 16 obtains the ambient temperature curve for the day via the network module and determines whether the future heating period falls within one-third of the day's highest temperature period, i.e., whether the current time is within the hottest part of the day. If so, the control box 16 directly heats the system to the user-set temperature T0+10℃ for high ambient temperature heat storage, utilizing the high energy efficiency of the heat pump at high ambient temperatures to store excess heat in the phase change material for later use. If not, the system only heats to the basic heating temperature T1, which is 45℃ by default, to meet only basic water usage needs and reduce energy consumption increases during periods of low ambient temperature.

[0025] During heating, the electrical control box 16 performs multi-parameter coordinated control; the compressor frequency is PID-regulated based on the difference between the upper and lower temperatures of the phase change hot water storage tank 12 and T0, respectively. The larger the difference, the higher the compressor frequency and the faster the heating speed; as the temperature gradually approaches T0, the compressor frequency gradually decreases to avoid overshoot and energy waste; the fan speed of the evaporation heat exchange module 7 is regulated based on the difference between the evaporation temperature 1 and the ambient temperature. The larger the difference, the higher the fan speed to enhance the heat absorption capacity of the evaporation heat exchanger; as the difference decreases, the fan speed decreases accordingly to reduce fan power consumption; the throttling valve adjusts its opening based on the system superheat, which is the difference between the evaporator outlet temperature and the evaporation temperature. The difference is controlled by adjusting the opening of the throttle valve to regulate the refrigerant flow into the evaporator, keeping the superheat within a reasonable range to prevent liquid slugging in the compressor and ensuring the evaporator's heat exchange efficiency. The flow regulating valve 2 adjusts its opening according to the evaporation temperature 2, controlling the target value of the evaporation temperature 2 to 3°C to 5°C to prevent the lower refrigerant recovery temperature of the dual heat recovery unit 8 from freezing when there is no shower. When the evaporation temperature 2 is below 3°C, the opening of the flow regulating valve 2 decreases, reducing the refrigerant flow into the lower refrigerant side of the dual heat recovery unit 8, causing the evaporation temperature 2 to rise. When the evaporation temperature 2 is above 5°C, the opening of the flow regulating valve 2 increases, increasing the refrigerant flow and enhancing the heat recovery effect.

[0026] The refrigerant circulation process is as follows: The high-temperature and high-pressure gaseous refrigerant, after being compressed by the compressor, is sent to the phase change hot water storage tank 12 through the fluorine inlet pipe in the fluorine system connector 15. It flows through the fluorine-side heat exchange microchannel 26, where it condenses and releases heat, transferring the heat to the phase change material for heat storage. During the condensation process, the refrigerant gradually becomes liquid. After being throttled and depressurized by the throttling valve, it becomes a low-temperature and low-pressure gas-liquid two-phase state. Then, it absorbs heat through the evaporative heat exchanger of the evaporative heat exchange module 7 and the lower fluorine-side heat recovery microchannel of the dual heat recovery unit 8. After absorbing heat from the air and bath wastewater, it becomes gaseous and returns to the compressor through the fluorine outlet pipe in the fluorine system connector 15 for the next heat exchange cycle.

[0027] When the upper and lower temperatures of the phase change hot water storage tank 12 meet the temperature-reaching shutdown conditions, that is, when both the upper and lower temperatures reach the target value T1, the compressor stops running and heating ends; thereafter, when a water flow signal is detected by the flow meter, that is, when the user turns on the hot water tap to start using hot water, the water heater enters the hot water usage mode.

[0028] In hot water usage mode, the water heater first opens the flow regulating valve 3, allowing water to flow through the inlet of the inlet / outlet pipe 19 into the water-side heat exchange coil 20 of the phase change hot water storage tank 12 for heating. At this time, cold water, after being preheated by the upper water-side heat recovery pipe of the dual heat recovery unit 8, enters the water-side heat exchange coil 20 through the inlet of the inlet / outlet pipe 19, exchanging heat with the phase change material and absorbing the heat stored in the material. After its temperature rises, it is output to the user's hot water point through the outlet of the inlet / outlet pipe 19. Simultaneously, the flow regulating valve 1 is fully open, allowing the high-temperature refrigerant to preferentially pass through the plate heat exchanger 13. The plate heat exchanger 13 is in a preheating state when there is no cold water or a small amount of cold water passing through, awaiting switching. When the condensing temperature of the plate heat exchanger 13 is not less than T0+T2, where T2 is assumed to be 15℃, it indicates that the plate heat exchanger 13 has reached the capability to heat the water to the target temperature. At this point, the flow regulating valve 1 opens fully. The flow regulating valve 4 is opened and the flow regulating valve 3 is closed simultaneously until the flow regulating valve 3 is completely closed, so that the water flow is completely switched to flow through the plate heat exchanger 13 for direct heating. During the switching process, the step adjustment of the flow regulating valves 3 and 4 is carried out step by step. Every time the flow regulating valve 4 is opened to a certain degree, the flow regulating valve 3 is closed to the same degree to ensure a smooth transition of water flow and avoid drastic fluctuations in the outlet water temperature. If the heat pump heating is insufficient during the process, causing fluctuations in the hot water outlet temperature, the flow regulating valve 3 is dynamically supplemented with heat by the difference between the real-time outlet water temperature and the target temperature. That is, when the outlet water temperature is lower than the target temperature, the flow regulating valve 3 is opened appropriately to allow some water to flow through the water-side heat exchange coil 20 of the phase change hot water storage tank 12 to supplement heat. When the outlet water temperature returns to normal, the flow regulating valve 3 is closed again to restore the direct heating of the plate heat exchanger 13.

[0029] After the initial heating shutdown of the phase change hot water storage tank 12, when a reading is detected on the flow meter, the control box 16 begins recording a 24-hour flow curve with a recording cycle of Z, where Z is defaulted to 20 days, meaning each 20-day period is a learning cycle. Simultaneously, data is recorded and processed using three factors: Factor 1 represents the normal working hours (Monday to Friday), Factor 2 represents weekends and holidays, and Factor 3 represents the four seasonal periods (spring, summer, autumn, and winter). By combining these three factors, eight daily water usage curves are obtained, including daily water usage curves for the normal working hours and non-working hours under different seasons. These curves reflect the user's water usage habits under different seasons and date types (working days or rest days). After completing the first Z-cycle of daily water usage curves, the control box 16 initiates real-time linkage, using the ambient temperature obtained via the internet as Factor 4 and the ambient temperature... The heating capacity due to temperature changes is used as factor 5 to intelligently predict the user's hot water demand. The prediction calculation big data model integrates five factors, from factors 1 to 5. Factors 1 to 3 are demand factors, reflecting the user's water usage habits and water demand; factors 4 to 5 are supply factors, reflecting the heat pump's heating capacity and energy efficiency level under different ambient temperatures. Based on the predicted demand model, a corresponding heating capacity calculation model is generated to formulate a reasonable operating strategy for different time periods. That is, under the premise of meeting the user's water demand, heat storage and heating are carried out during periods with higher ambient temperatures and better heat pump heating efficiency, avoiding periods with low ambient temperatures and poor heating efficiency to achieve economical operation. Furthermore, the combination scheme of water heater start-up and shutdown and variable frequency operation is determined, that is, based on the prediction results, the combination of control parameters such as when to start heating, when to stop heating, the frequency of compressor operation, and the speed of fan operation are determined.

[0030] Finally, when the heat pump water heater is not heating and bathroom ventilation is required, the fan of the evaporative heat exchange module 7 is turned on by controlling it with a wireless switch. At this time, the flow regulating valve 2 is in the closed state, the refrigerant does not flow through the evaporative heat exchange module 7, and the fan is only used to exhaust the moisture and odors in the bathroom to the outside, realizing a ventilation mode of ventilation without heat exchange, meeting the daily ventilation needs of the bathroom, and avoiding energy loss caused by refrigerant circulation when the fan is running.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention; any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A phase change direct heating bathroom heat recovery heat pump water heater, characterized in that, It includes three modules: a phase change heat pump unit, an evaporative heat exchange module, and a dual heat recovery unit; The phase change heat pump unit features an ultra-thin wall-mounted design, installed in indoor bathrooms or balconies, similar to the installation method of traditional electric or gas water heaters. The internal structure of the phase change heat pump unit includes a compressor, a four-way valve, a phase change hot water storage tank, a plate heat exchanger, a throttling valve, and a flow regulating valve 1. Following the reverse Carnot cycle principle, the phase change heat pump unit absorbs heat from the evaporative heat exchange module and the dual heat recovery unit, and transfers this heat to the phase change hot water storage tank and the plate heat exchanger through refrigerant circulation. Externally, the phase change heat pump unit is connected to the evaporative heat exchange module and the dual heat recovery unit via a refrigerant pipe for refrigerant heating circulation. Simultaneously, externally, it is connected to the dual heat recovery unit via a water pipe for preheating and recovering cold water, and then connects the hot water to the user's hot water pipe. The evaporative heat exchange module is installed at the bathroom exhaust vent and has a built-in ventilation recognition mode, including mode 1 and mode 2. Mode 1 is the heating mode, which is activated when the heat pump is heating to absorb heat through the evaporative heat exchanger and exhaust the cold air to the outside. Mode 2 is the ventilation mode, which is activated when the heat pump is not heating but bathroom ventilation is required. The fan is controlled by a wireless switch, and only the fan is activated while the flow regulating valve 2 is closed. The flow regulating valve 2 is located on the refrigerant inlet pipe of the evaporative heat exchange module. The dual heat recovery unit has a two-layer structure: the upper layer is water-side heat recovery, which is formed by a single tube in an S-shape. It is used to preheat the inlet water entering the phase change heat pump host, and then heat it to the target outlet water temperature in the plate heat exchanger or phase change hot water storage tank. The lower layer is for fluorine-side heat recovery, consisting of a lower layer microchannel heat exchange plate. It is used to perform phase change enthalpy increase on the fluorine refrigerant entering the phase change heat pump host to improve the circulation efficiency of the fluorine system, and to reduce the water temperature in the lower layer to a near-freezing state of 3°C to 5°C.

2. The phase change direct heating bathroom heat recovery heat pump water heater according to claim 1, characterized in that, The phase change heat pump unit also includes a heat pump system installation area, a refrigerant system connector, an electrical control box, a wired controller, and an insulation shell. The heat pump system installation area is located in the upper part of the phase change heat pump unit and is used to install the compressor, plate heat exchanger, electrical control box, various valves, and pipe bends. The refrigerant system connector connects the phase change heat pump unit to the evaporative heat exchange module and the dual heat recovery unit to achieve refrigerant heating circulation. In hot water usage mode, the plate heat exchanger directly heats the inlet water that has been preheated by the initial water recovery in the dual heat recovery unit, and delivers it to the user's hot water point after reaching the target outlet temperature. The electrical control box is used for... The system collects parameters such as ambient temperature, plate heat exchanger condensing temperature, upper and lower water tank temperatures, flow meter and flow regulating valve parameters, as well as the evaporation temperature 1 of the evaporation heat exchange module and the evaporation temperature 2 of the dual heat recovery unit. Based on the collected parameters, it adjusts the compressor operating frequency, fan speed, throttle valve opening, and the opening of each flow regulating valve. The wired controller is used to provide feedback and operate the overall operating status, target water temperature, operating mode, and automatic operation phase of the phase change direct heating bathroom heat recovery heat pump water heater. The insulation shell is used for structural protection and support of the phase change heat pump main unit, and also serves as sound insulation and heat preservation.

3. A phase change direct heating bathroom heat recovery heat pump water heater according to claim 1, characterized in that, The phase change hot water storage tank stores the heat provided by the heat pump in the phase change material, and has built-in water-side heat exchange coils and fluorine-side heat exchange microchannels. The water-side heat exchange coils are single copper tubes, arranged in an S-shape from top to bottom, and flow counter-currently with the fluorine-side heat exchange microchannels. The fluorine-side heat exchange microchannels are used to heat the phase change material in the phase change hot water storage tank with the heat provided by the phase change heat pump unit. The fluorine-side heat exchange microchannels are divided into three groups of parallel microchannels, with the number of parallel microchannels in each group decreasing progressively. The heating method is as follows: first, four parallel microchannels form the upper part of the first group of heating from left to right; then, three parallel microchannels form the middle part of the second group of heating from right to left; and finally, two parallel microchannels form the lower part of the third group of heating from left to right. The phase change hot water storage tank is also equipped with fluorine inlet, fluorine outlet, upper temperature sensor, lower temperature sensor, hot water inlet, and hot water outlet. A flow regulating valve 3 is installed on the hot water inlet pipe to control the water flow rate through the water-side heat exchange coil of the phase change hot water storage tank.

4. A phase change direct heating bathroom heat recovery heat pump water heater according to claim 1, characterized in that, The evaporative heat exchange module includes an evaporative heat exchanger, a fan, fan blades, and a flow regulating valve 2. The flow regulating valve 2 is installed on the refrigerant inlet pipe of the evaporative heat exchange module and is used to control the refrigerant flow rate entering the evaporative heat exchange module. The evaporative heat exchange module is used in conjunction with a wireless switch: in the phase change heat pump main unit's heating mode, regardless of whether the wireless switch is turned on or off, the fan automatically adjusts its speed according to the heating demand to absorb heat through the evaporative heat exchanger and exhaust the cold air to the outside; in the heat pump's non-heating mode, when the wireless switch is turned on, the fan starts directly for ventilation, but the flow regulating valve 2 is in the closed state.

5. A phase change direct heating bathroom heat recovery heat pump water heater according to claim 1, characterized in that, The dual heat recovery unit is also equipped with a tap water inlet, a water-side heat recovery pipe, a lower-level fluorine inlet and outlet, and a temperature sensor for detecting the evaporation temperature 2; the plate heat exchanger cold water supply pipeline of the phase change heat pump host is equipped with a flow regulating valve 4 to control the flow rate of cold water entering the plate heat exchanger.

6. An AI intelligent control method for a phase change direct heating bathroom heat recovery heat pump water heater, said method being implemented based on a phase change direct heating bathroom heat recovery heat pump water heater as described in any one of claims 1 to 5, characterized in that, The method includes the following steps: Step 1: The water heater is powered on and it is determined whether the upper and lower temperatures of the phase change heat storage tank are not less than the user-set temperature T0. If so, the heating system is not started; otherwise, the phase change heat pump unit is started for heating. At this time, the ambient temperature curve of the day is obtained online, and it is confirmed whether the future heating period is more than 1 / 3 of the highest temperature period of the ambient temperature curve of the day. If so, it is directly heated to the user-set temperature T0 + 10℃ for high ambient temperature heat storage; otherwise, it is only heated to the basic heating temperature T1, where ℃ is degrees Celsius. Step 2: After the water heater determines that the phase change heat storage tank is heating, the compressor frequency is adjusted by PID according to the difference between the upper and lower temperatures of the phase change heat storage tank and T0, respectively. The fan speed of the heat exchange module is adjusted according to the difference between the evaporation temperature 1 and the ambient temperature, and the opening of the throttling valve is adjusted according to the system superheat. The opening of the flow regulating valve 2 is adjusted according to the evaporation temperature 2, controlling the target evaporation temperature of evaporation temperature 2 to be 3℃ to 5℃. During the heat pump heating process, the high-temperature refrigerant, after being compressed and heated by the compressor, is sent to the phase change heat storage tank to heat the phase change material for heat storage. After throttling, the refrigerant passes through the evaporation heat exchange module and the dual heat recovery module to absorb heat, and then returns to the compressor for the next round of heat exchange. Step 3: When the upper and lower temperatures of the phase change heat storage tank meet the temperature-reaching shutdown requirements, and when a water flow signal is detected by the flow meter, i.e., when the user starts using hot water, the water heater first opens the flow regulating valve. Regulating valve 3 allows water to flow through the water-side heat exchange coils of the phase change heat storage tank for heating, and flow regulating valve 1 is fully open, allowing the high-temperature refrigerant to preferentially pass through the plate heat exchanger; when the condensing temperature of the plate heat exchanger is not less than T0 + T2, flow regulating valve 4 is gradually opened and flow regulating valve 3 is closed synchronously until flow regulating valve 3 is completely closed, so that the water flow is completely switched to flow through the plate heat exchanger for direct heating; if the heat pump heating is insufficient during the process, causing the hot water outlet temperature to fluctuate, the flow regulating valve 3 is dynamically supplemented with heat by the difference between the real-time outlet temperature and the target temperature; Step 4, the intelligent operation of the water heater for heating the phase change hot water storage tank: after the phase change hot water storage tank stops heating for the first time, when a reading is detected on the flow meter... The system begins recording 24-hour flow curves with Z as a recording period, while simultaneously recording and processing data based on three factors: Factor 1 represents the normal working hours; Factor 2 represents weekends and public holidays; and Factor 3 represents the four seasonal periods. This process yields eight different daily water consumption curves, including those for the normal working hours and those for non-working hours under different seasons. After completing the first Z-cycle of daily water consumption curves, the system initiates real-time linkage, using the ambient temperature obtained via the internet as Factor 4 and the heating capacity varying with ambient temperature as Factor 5, to intelligently predict user hot water demand. The prediction calculation big data model integrates five factors from Factor 1 to Factor 5, where Factors 1 to 3 represent demand factors, and Factors 4 to 5 represent supply factors.Based on the predicted demand model, a corresponding heating capacity calculation model is generated to formulate an operating strategy for appropriate time periods, thereby determining the combination of water heater start-up / shutdown and frequency converter operation.

7. The AI ​​intelligent control method for a phase change direct heating bathroom heat recovery heat pump water heater according to claim 6, characterized in that, The user-set temperature T0 is 55℃; the basic heating temperature T1 is 45℃; the temperature T2 is 15℃; and the cycle Z is 20 days.

8. The AI ​​intelligent control method for a phase change direct heating bathroom heat recovery heat pump water heater according to claim 6, characterized in that, When the heat pump water heater is not heating and bathroom ventilation is required, the fan of the evaporative heat exchange module can be turned on by wireless switch. At this time, the flow regulating valve 2 is in the closed state, realizing a ventilation mode of ventilation only without heat exchange.

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