Photovoltaic direct drive steam and hot water integrated device and use method

Abstract

The application relates to a photovoltaic direct-drive steam and hot water integrated device and a use method, and belongs to the technical field of new energy heating and steam heating. The photovoltaic direct-drive steam and hot water integrated device comprises a steam and hot water integrated generation unit, a direct-current heating assembly, an alternating-current heating assembly, a photovoltaic power supply unit, a commercial power conversion and heat supplement unit, a commercial power direct supply unit and a control unit. When the power generation power of the photovoltaic power supply unit is lower than a preset power threshold, the control unit judges load demand. If the control unit judges that the load demand is lower than a preset load threshold, the commercial power conversion and heat supplement unit is started to convert alternating-current commercial power into direct-current power to supply power to the direct-current heating assembly. If the control unit judges that the load demand is higher than or equal to the preset load threshold, the commercial power direct supply unit is started to supply power to the alternating-current heating assembly. The application has the effects of realizing efficiency optimization of the device under different working conditions and enhancing scene adaptability and universality.

Description

Technical Field

[0001] This application relates to the fields of new energy heating and steam heating technology, and in particular to a photovoltaic direct-drive integrated steam hot water device and its usage method. Background Technology

[0002] To reduce reliance on traditional fossil fuels, utilizing renewable energy sources such as solar power has become an important development direction for the industry. Among these, photovoltaic power generation technology, due to its advantages such as wide resource distribution and high system integration, is gradually being introduced into the fields of steam air conditioning and hot water supply.

[0003] Traditional photovoltaic (PV) power generation and consumption systems typically employ a "PV power generation + inverter + AC power distribution + terminal equipment" model. This means the direct current (DC) generated by the PV modules needs to be converted to alternating current (AC) by an inverter before being supplied to terminal equipment such as hot water systems or air conditioners. This model involves multiple energy conversion stages, resulting in significant losses and low energy utilization.

[0004] Currently, related technologies, such as the Chinese patent document with publication number CN218722255U, disclose a mode that prioritizes direct DC output from photovoltaic power to supply terminal equipment. This system also connects to the mains power grid, automatically switching to AC mains direct power supply mode when the photovoltaic power generation is below a preset threshold. However, if photovoltaic power generation is insufficient and the electrical load demand is low, the system still switches to mains power at high power, which can easily generate excess heat, causing thermal inertia overshoot and frequent start-stop cycles, leading to reduced overall energy efficiency and making it difficult to meet the diverse load demands of application scenarios such as residential homes, factories, hotels, and high-altitude pastoral areas. Summary of the Invention

[0005] To help optimize the efficiency of the device under different operating conditions and enhance its adaptability and versatility, this application provides a photovoltaic direct-drive integrated steam and hot water device and its usage method.

[0006] Firstly, this application provides a photovoltaic direct-drive integrated steam and hot water device, which adopts the following technical solution: A photovoltaic direct-drive integrated steam and hot water device includes: The integrated steam and hot water generating unit is used to connect to external steam air conditioning and heating pipes and domestic water pipes respectively; A DC heating element is installed in the integrated steam and hot water generation unit; An AC heating component is installed in the integrated steam and hot water generation unit; A photovoltaic power supply unit is electrically connected to the DC heating component. The photovoltaic power supply unit is used to convert solar energy into DC power and supply power to the DC heating component. The AC power conversion and heating unit is electrically connected to the DC heating component. The AC power conversion and heating unit is used to convert AC mains power into DC power and supply it to the DC heating component. A mains power supply unit is electrically connected to the AC heating component, and the mains power supply unit is used to supply power to the AC heating component. The control unit is electrically connected to the DC heating component, AC heating component, photovoltaic power supply unit, mains power conversion and supplementary heating unit, and mains power direct supply unit, respectively. When the power generation of the photovoltaic power supply unit is lower than the preset power threshold, the control unit determines the load demand. If the control unit determines that the load demand is lower than the preset load threshold, it starts the mains power conversion and supplementary heating unit to convert AC mains power into DC power to supply power to the DC heating component. If the control unit determines that the load demand is higher than or equal to the preset load threshold, it starts the mains power direct supply unit to supply power to the AC heating component.

[0007] Preferably, the integrated steam and hot water generating unit includes an integrated water storage and steam housing, a water inlet pipe, a hot water output pipe, and a steam output pipe. The water inlet pipe, hot water output pipe, and steam output pipe are all connected to the integrated water storage and steam housing. The water inlet pipe is used to connect to an external water supply pipe, the hot water output pipe is used to connect to a domestic water supply pipe, and the steam output pipe is used to connect to an external steam air conditioning and heating pipe. The DC heating component and the AC heating component are both installed inside the integrated water storage and steam housing.

[0008] Preferably, the integrated water and steam storage box includes an outer shell, an insulation layer, and an inner liner arranged sequentially from the outside to the inside. Both the DC heating component and the AC heating component are installed in the inner liner. A drain pipe is connected to the integrated water and steam storage box, and a safety valve is installed on the top of the integrated water and steam storage box.

[0009] Preferably, the DC heating component includes a DC low-voltage heating tube, and a 48V low-voltage resistance wire is disposed inside the DC low-voltage heating tube.

[0010] Preferably, the AC heating assembly includes an insulated heating tube, and a leakage protection current-limiting resistor is connected in series at the inlet terminal of the insulated heating tube.

[0011] Preferably, the photovoltaic power supply unit includes a photovoltaic panel and an MPPT voltage regulator module, wherein the MPPT voltage regulator module is electrically connected to the photovoltaic panel and the DC heating component, respectively.

[0012] Preferably, the mains power conversion and heating unit includes a step-down and voltage-stabilizing module, which is electrically connected to the AC mains power and is connected in parallel with the DC heating component.

[0013] Preferably, the integrated water and steam storage box is equipped with a partition, which divides the integrated water and steam storage box into a heating chamber and an evaporation chamber. The water inlet pipe and the hot water output pipe are both connected to the heating chamber, and the steam output pipe is connected to the evaporation chamber. The DC heating component and the AC heating component both extend through both ends of the partition into the heating chamber and the evaporation chamber, respectively. The partition has multiple connecting holes, and the partition is equipped with an adjustment component for adjusting the opening and closing degree of the connecting holes.

[0014] Preferably, the adjustment assembly includes a sealing body, a support spring, and a shape memory metal adjusting plate. Each sealing body corresponds to a connecting hole and is slidably mounted on the partition. The sealing body is used to move towards or away from the corresponding connecting hole. The support spring is mounted on the partition. When the support spring is in its natural state, it blocks one side of the corresponding connecting hole. The shape memory metal adjusting plate corresponds to the sealing body and is positioned between the partition and the corresponding sealing body. When the shape memory metal adjusting plate is in its initial bent state, the sealing body blocks one side of the corresponding connecting hole. When the shape memory metal adjusting plate extends to a straight state after the temperature rises, it pushes the corresponding sealing body to move away from the connecting hole.

[0015] Secondly, the method of using the photovoltaic direct-drive integrated steam and hot water device provided in this application adopts the following technical solution: A method of using a photovoltaic direct-drive integrated steam and hot water device, which utilizes the integrated device, includes the following steps: The power generation of the photovoltaic power supply unit is collected by the power acquisition module and fed back to the control unit; The control unit receives the power generation of the photovoltaic power supply unit from the power acquisition module and compares it with a preset power threshold. If the power generation of the photovoltaic power supply unit is greater than or equal to the preset power threshold, the photovoltaic power supply unit is connected to the DC heating component, allowing the photovoltaic power supply unit to directly drive the DC heating component to heat the water in the integrated steam and hot water generation unit. The water in the integrated steam and hot water generation unit is heated to produce hot water and steam. If the power generation of the photovoltaic power supply unit is lower than the preset power threshold, the control unit continues to determine the load demand. If the control unit determines that the load demand is lower than the preset load threshold, it activates the AC power conversion and heating unit to convert AC AC power into DC power to supply the DC heating component. If the control unit determines that the load demand is greater than or equal to the preset load threshold, it activates the AC power direct supply unit to supply power to the AC heating component. A temperature sensor is used to detect the water temperature in the integrated steam and hot water generating unit and feed it back to the control unit. When the control unit receives the water temperature in the integrated steam and hot water generating unit and it reaches the preset temperature threshold, the control unit cuts off the power supply circuits of the photovoltaic power supply unit, the mains power conversion and heating unit and the mains power direct supply unit. The high-temperature steam output from the integrated steam and hot water generator is delivered to the steam air conditioning terminal to achieve heating, while the output hot water is directly supplied to domestic water use.

[0016] In summary, this application includes the following beneficial technical effects: This application prioritizes photovoltaic DC direct-drive heating when photovoltaic power supply is sufficient, eliminating the need for inverters and helping to reduce power loss. When photovoltaic power is insufficient, it intelligently selects the supplementary heating path according to load demand. Under low load demand conditions, the mains power conversion supplementary heating unit is activated as an auxiliary supplementary heating method. At this time, the load demand is small, and the conduction loss and switching loss of the rectification and step-down stage are within a controllable range, resulting in high supplementary power supply efficiency. Under high load demand conditions, the mains power direct supply unit directly supplies power to the AC heating components, which helps to achieve a smooth transition and optimization of the device's efficiency under different operating conditions. This makes the device adaptable to various scenarios such as residential guesthouses, factories, hotels, and off-grid areas in high-altitude pastoral regions, enhancing the device's scenario adaptability and versatility. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the integrated device in Embodiment 1 of this application.

[0018] Figure 2 This is a partial structural cross-sectional view of the integrated device in Embodiment 1 of this application.

[0019] Figure 3 This is a structural cross-sectional view of the integrated water and steam storage box in Embodiment 2 of this application.

[0020] Figure 4 This is a partial structural schematic diagram of Embodiment 2 of this application.

[0021] Figure 5 This is a partial structural cross-sectional view of Embodiment 2 of this application.

[0022] Explanation of reference numerals in the attached drawings: 1. Integrated steam and hot water generating unit; 11. Integrated water and steam storage box; 111. Outer shell; 112. Insulation layer; 113. Inner tank; 12. Water inlet pipe; 13. Hot water output pipe; 14. Steam output pipe; 2. Photovoltaic power supply unit; 21. Photovoltaic panel; 22. MPPT voltage regulator module; 3. Mains power conversion and supplementary heating unit; 4. Mains direct power supply unit; 5. DC low-voltage heating tube; 6. Insulated heating tube; 7. Leakage protection current limiting resistor; 8. Partition plate; 9. Heating chamber; 10. Evaporation chamber; 15. Connecting hole; 16. Sealing body; 17. Support spring; 18. Memory metal adjusting plate; 19. Support; 20. Drain hole; 23. Conical sealing plug; 24. Limiting strip; 25. Mounting base; 26. Mounting piece; 27. Sliding piece; 28. Connecting rope; 29. ​​Drain pipe; 30. Safety valve. Detailed Implementation

[0023] The following combination Figures 1-5 This application will be described in further detail.

[0024] Example 1:

[0025] This application discloses a photovoltaic direct-drive integrated steam and hot water device. (Refer to...) Figure 1 and Figure 2 The photovoltaic direct-drive integrated steam and hot water system includes a steam and hot water generation unit 1, a DC heating component, an AC heating component, a photovoltaic power supply unit 2, a mains power conversion and supplementary heating unit 3, a mains power direct supply unit 4, and a control unit. The steam and hot water generation unit 1 is connected to both external steam air conditioning heating pipes and domestic water pipes. The unit contains water to be heated and simultaneously outputs high-temperature steam and hot water. The high-temperature steam is delivered to the steam air conditioning terminal for heating, while the hot water is directly supplied to bathrooms, kitchens, and other domestic water uses.

[0026] Reference Figure 2 Specifically, a DC heating component is installed within the integrated steam and hot water generation unit 1 to receive DC electrical energy and convert it into heat energy to heat the water within the integrated steam and hot water generation unit 1. Similarly, an AC heating component is installed within the integrated steam and hot water generation unit 1 to receive AC electrical energy and convert it into heat energy to heat the water.

[0027] Reference Figure 2Specifically, the photovoltaic power supply unit 2 is located outside the integrated steam and hot water generation unit 1. The photovoltaic power supply unit 2 is electrically connected to the DC heating component and is used to convert solar energy into DC power and supply it to the DC heating component. The photovoltaic power supply unit 2 serves as the primary energy input for the entire device, and its power generation varies in real time with light intensity and ambient temperature. In this embodiment, a voltage sensor and a current sensor are installed on the output line of the photovoltaic power supply unit 2 as a power acquisition module to help detect the power generation of the photovoltaic power supply unit 2. In other embodiments, a light sensor can also be installed on the photovoltaic power supply unit 2 to detect the light intensity and provide feedback on the power generation of the photovoltaic power supply unit 2.

[0028] Reference Figure 2 The AC mains power conversion and heating unit 3 is electrically connected to the DC heating component, used to convert AC mains power to DC power and provide DC supplementary power to the DC heating component; the AC mains power direct supply unit 4 is electrically connected to the AC heating component, used to directly provide AC mains power to the AC heating component. The control unit is the intelligent control center of the entire device and can be a PLC controller. Specifically, the control unit is electrically connected to the DC heating component, AC heating component, photovoltaic power supply unit 2, AC mains power conversion and heating unit 3, and AC mains power direct supply unit 4. When the power generation of photovoltaic power supply unit 2 is lower than the preset power threshold, the control unit judges the load demand. If the load demand is lower than the preset load threshold, the AC mains power conversion and heating unit 3 is activated to convert AC mains power to DC power to supply power to the DC heating component; if the load demand is higher than or equal to the preset load threshold, the AC mains power direct supply unit 4 is activated to supply power to the AC heating component.

[0029] During operation, the control unit collects the power generation of the photovoltaic power supply unit 2 through the power acquisition module. When the power generation is greater than or equal to the preset power threshold, it is determined that the photovoltaic power supply is sufficient and the photovoltaic power supply unit 2 is directly connected to the DC heating component. When the power generation is less than the preset power threshold, the control unit further judges the load demand. If the load demand is lower than the preset load threshold, the mains power conversion and heating unit 3 is activated to convert the AC mains power into DC power to supply the DC heating component. If the load demand is higher than or equal to the preset load threshold, the mains power direct supply unit 4 is activated to supply power to the AC heating component.

[0030] This application prioritizes direct-drive photovoltaic heating when photovoltaic power is sufficient, eliminating the need for inverters and reducing energy loss. When photovoltaic power is insufficient, it intelligently selects the supplementary heating path based on load demand. In low-load conditions, such as residential and guesthouse scenarios, the mains power conversion supplementary heating unit 3 is activated as an auxiliary supplementary heating method. At this time, the load demand is small, and the conduction and switching losses of the rectification and step-down stages are within a controllable range, resulting in high supplementary power supply efficiency. In high-load conditions, such as factories and hotels with rapid heating under heavy loads, the mains power direct supply unit 4 bypasses the rectification stage and directly supplies power to the AC heating components. This helps to achieve a smooth transition and optimization of the device's efficiency under different operating conditions, making it adaptable to residential, guesthouse, factory, hotel, and off-grid scenarios in high-altitude pastoral areas, thus enhancing the device's scenario adaptability and versatility.

[0031] Reference Figure 2 Specifically, to facilitate the simultaneous generation of high-temperature steam and hot water after heating the water, the integrated steam and hot water generating unit 1 includes an integrated water storage and steam tank 11, a water inlet pipe 12, a hot water output pipe 13, and a steam output pipe 14. The integrated water storage and steam tank 11 serves as the main container for water storage, and its shape and size can be set as needed. Both the DC heating component and the AC heating component are installed inside the integrated water storage and steam tank 11. The water inside the tank is heated to boiling or near boiling state by the DC heating component or the AC heating component, thereby generating high-temperature steam and hot water simultaneously.

[0032] Reference Figure 2 The water inlet pipe 12 is connected to one end of the integrated water storage and steam tank 11 and is used to connect with the external water supply pipe, so that tap water or other water sources can be introduced into the tank through the water inlet pipe 12. Furthermore, in order to control the water inlet flow rate and improve the quality of the water entering the integrated water storage and steam tank 11, a filter and a water inlet valve can be installed on the water inlet pipe 12.

[0033] Reference Figure 2 The hot water output pipe 13 is connected to the bottom of the integrated water storage and steam tank 11, and is used to connect with the domestic water pipe. The heated hot water in the tank is output to domestic water terminals such as bathrooms and kitchens through the hot water output pipe. Furthermore, in other embodiments, a hot water pump and a mixing valve can be installed on the hot water output pipe 13 to adjust the output water temperature and flow rate.

[0034] Reference Figure 2The steam output pipe 14 is connected to the top of the integrated water storage and steam tank 11, and is used to connect to the external steam air conditioning and heating pipes. The high-temperature steam generated inside the tank is transported to the steam air conditioning terminal through the steam output pipe 14 to achieve winter heating. In other embodiments, a steam valve and a pressure reducing valve can also be installed on the steam output pipe 14 to regulate steam pressure and output. To improve safety, a steam pressure protection safety valve 30 is installed on the top of the integrated water storage and steam tank 11.

[0035] By cooperating with the water inlet pipe 12, hot water output pipe 13, and steam output pipe 14, and the integrated water storage and steam unit 11, the integrated water storage and steam unit 11 can simultaneously output steam and hot water, replacing two separate sets of equipment, namely a separate steam boiler and a water heater, thus reducing the equipment footprint and installation costs.

[0036] Reference Figure 2 Furthermore, in order to facilitate the regular removal of scale, silt and other impurities deposited at the bottom of the integrated water and steam storage box 11, and to maintain the cleanliness of the integrated water and steam storage box 11 and the efficient operation of the heating components, the lower end of the integrated water and steam storage box 11 is also connected to a drain pipe 29 with a valve. The valve on the drain pipe 29 is opened for drainage during maintenance and closed during normal operation.

[0037] Reference Figure 2 A temperature sensor is installed inside the integrated water and steam storage tank 11. The temperature sensor detects the water temperature inside the integrated water and steam storage tank 11 and feeds it back to the control unit. When the control unit receives the water temperature inside the integrated water and steam storage tank 11 reaching the preset temperature threshold, the control unit cuts off the photovoltaic power supply unit, the mains power conversion heating unit, and the mains direct power supply unit. In other embodiments, the DC low-voltage heating tube 5 and the insulated heating tube 6 can be equipped with independent temperature controllers. The temperature controllers are connected to the control unit and feed the temperature data back to the control unit in real time. Since the temperature controllers can independently monitor the working temperature of the corresponding heating components, they can automatically cut off the power supply to the corresponding heating components when the water temperature exceeds the set upper limit to prevent dry burning and overheating, which helps to achieve precise temperature control and multiple safety protections.

[0038] Reference Figure 2 Furthermore, a water level sensor can also be installed inside the integrated water and steam storage tank 11. The water level sensor detects the water level height of the integrated water and steam storage tank 11 and feeds it back to the control unit. When the control unit receives that the water level inside the integrated water and steam storage tank 11 has reached a preset height, the control unit controls the opening of the water inlet valve on the water inlet pipe 12 to decrease or close.

[0039] Reference Figure 2Furthermore, to improve the insulation effect of the integrated water and steam storage tank 11, the integrated water and steam storage tank 11 includes an outer shell 111, an insulation layer 112, and an inner liner 113, fixed sequentially from the outside to the inside. The outer shell 111, as the outermost structure of the tank, is typically made of metal sheet, such as stainless steel or galvanized steel, possessing sufficient mechanical strength and corrosion resistance to protect the internal structure from external environmental influences. The insulation layer 112 is located between the outer shell 111 and the inner liner 113, and is typically made of low thermal conductivity materials such as polyurethane foam, rock wool, or glass wool. Its thickness is rationally designed according to the tank volume and ambient temperature. The inner liner 113 is located inside the insulation layer 112, directly containing the water to be heated. Both the DC heating component and the AC heating component are located within the inner liner 113. The inner liner 113 is primarily made of corrosion-resistant and high-temperature-resistant materials, with a smooth surface that is not prone to scaling.

[0040] Reference Figure 2 To facilitate the reception of DC power and its conversion into heat energy, the DC heating component includes a DC low-pressure heating tube 5. To facilitate the installation of the DC low-pressure heating tube 5, a mounting base 25 is fixed at one end of the integrated water storage and steam tank 11. The DC low-pressure heating tube 5 is installed on the mounting base 25, so that the DC low-pressure heating tube 5 is located in the water in the inner tank 113. The shape of the DC low-pressure heating tube 5 can be designed as a straight line, a wave, a U-shape, or a spiral shape, etc., without any restrictions.

[0041] Reference Figure 2 Specifically, a 48V low-voltage resistance wire is installed inside the DC low-voltage heating tube 5. The 48V low-voltage resistance wire is the core heating element of DC heating, and 48V is within the safe low-voltage range. Even if leakage occurs, it will not cause electric shock to the human body, thus improving the safety of use.

[0042] When the photovoltaic power supply unit 2 or the mains power conversion and heating unit 3 supplies 48V DC power to the DC low-voltage heating tube 5, the 48V low-voltage resistance wire is energized and heats up. The heat is transferred to the water through the tube wall of the DC low-voltage heating tube 5, thus heating the water. The 48V DC power supply method is directly matched with the DC output of the photovoltaic panel 21, without the need for an inverter, resulting in high energy conversion efficiency.

[0043] Reference Figure 2To facilitate the reception of AC power and its conversion into heat energy for water heating, the AC heating assembly includes an insulated heating tube 6, which is also mounted on the mounting base 25, placing it within the water in the inner tank 113. Since the AC heating assembly is directly powered by 220V AC mains electricity, its leakage protection performance is crucial. In this application, the resistance wire inside the insulated heating tube 6 is sealed using a multi-layer insulation structure and a special process to ensure that the insulation resistance between the resistance wire and the water meets safety standards. Simultaneously, a leakage protection current-limiting resistor 7 is connected in series at the input terminal of the resistance wire in the insulated heating tube 6. This reduces the leakage voltage through voltage division in the event of insulation degradation or leakage fault, limiting the current that may leak into the water to a safe range.

[0044] Reference Figure 2 To further improve electrical safety, a grounding isolation layer can be added to the inner wall of the inner tank 113. Even if the insulation layer in the AC heating component is slightly damaged, the leakage protection current limiting resistor 7 can reduce the leakage current of the water to the safe milliampere level for the human body, effectively solving the defect of death caused by leakage from 220V high-voltage water ingress, and greatly improving safety redundancy.

[0045] Reference Figure 2 To facilitate the conversion of solar energy into DC power and supply power to the DC heating component, the photovoltaic power supply unit 2 includes a photovoltaic panel 21 and an MPPT voltage regulator module 22. The MPPT voltage regulator module 22 is electrically connected to the 48V low-voltage resistance wire in the photovoltaic panel 21 and the DC heating component, respectively. The photovoltaic panel 21 is installed in a location with sufficient sunlight, such as the roof or exterior wall of a building, to directly convert solar radiation energy into DC power. One or more photovoltaic panels 21 can be installed. The open-circuit voltage and maximum power point voltage of the photovoltaic panel 21 are designed to match the rated voltage of the DC heating component.

[0046] Reference Figure 2 The MPPT regulator module 22, short for Maximum Power Point Tracking, is a voltage regulator module whose structure and principle are existing technologies and will not be elaborated here. The MPPT regulator module 22 helps adjust the load impedance to ensure that the photovoltaic panel 21 always operates at its maximum power point, thereby maximizing photovoltaic energy capture efficiency. Simultaneously, the MPPT regulator module 22 also regulates the fluctuating DC output of the photovoltaic panel 21 to 48V DC to match the rated operating voltage of the DC low-voltage heating element 5. Since changes in light intensity and temperature can cause fluctuations in the output characteristics of the photovoltaic panel 21, the MPPT regulator module 22 continuously tracks the maximum power point through high-frequency PWM or MPPT algorithms to ensure that the output power of the photovoltaic panel 21 is optimal under various lighting conditions.

[0047] To facilitate energy storage, in other embodiments, the photovoltaic power supply unit 2 may also include a battery. The battery is electrically connected to the photovoltaic panel 21, the MPPT voltage regulator module 22, the DC heating component, and the control unit. When there is sufficient sunlight, the photovoltaic panel 21 generates electricity, and the battery stores energy and outputs electrical energy to the DC heating component. When there is insufficient sunlight, the photovoltaic panel 21 does not generate electricity, but the battery can output electrical energy to the DC heating component.

[0048] Reference Figure 2 The AC mains power conversion and heating unit 3 includes a step-down voltage regulator module. The input of the step-down voltage regulator module is connected to the AC mains power supply, and the output terminal outputs 48V DC power to match the rated operating voltage of the DC heating component. The specific structure of the step-down voltage regulator module is existing technology and will not be described in detail here. The step-down voltage regulator module and the DC heating component are connected in parallel. When the control unit determines that the photovoltaic power supply is insufficient and the load demand is lower than the preset load threshold, it activates the step-down voltage regulator module to supplement the power supply to the DC heating component, allowing the DC heating component to continue operating. Because the load demand is low at this time, the step-down voltage regulator module operates in a low-power state, resulting in lower conduction and switching losses in its rectification stage, higher safety, and improved overall energy efficiency.

[0049] Reference Figure 2 The mains power supply unit 4 includes an AC relay, which is electrically connected to the AC mains power, the AC heating component and the control unit. The AC relay is controlled by the control unit to connect or disconnect the circuit connection between the mains power and the AC heating component.

[0050] When the control unit determines that the photovoltaic power supply is insufficient and the load demand is higher than or equal to the preset load threshold, it controls the AC relay to close and directly drives the AC heating component to work through 220V AC power, thereby avoiding power loss in the rectification stage under high load conditions.

[0051] Reference Figure 2 In this application, the load demand mainly refers to the electrical power required by the DC heating components and AC heating components. In this embodiment, the control unit determines the load demand based on the current or power of the heating components, and the electrical power consumed is the load demand. In other embodiments, the heating demand can be calculated based on the temperature difference. The control unit receives the real-time water temperature detected by the temperature sensor and compares it with the preset target temperature. When the temperature difference is large, it indicates that the water temperature in the integrated water and steam storage tank 11 is far from the target temperature, which means that more heating power is required, and the load demand is high. When the temperature difference is small, the load demand is low. Alternatively, the load demand can be determined based on the water flow rate or water consumption. Flow sensors are installed on the hot water output pipeline and / or steam output pipeline to monitor the consumption of hot water and / or steam in real time. When the user uses a large amount of hot water or steam, the flow sensor detects a high flow signal, and the control unit determines that the load demand is high; otherwise, it is determined to be low load demand.

[0052] The implementation principle of the integrated device in Embodiment 1 of this application is as follows: During operation, the water inlet pipe 12 introduces tap water or other water sources into the integrated water storage and steam tank 11. The control unit collects the power generation power of the photovoltaic power supply unit 2 through the power acquisition module. When the power generation power is greater than or equal to the preset power threshold, it is determined that the photovoltaic power supply is sufficient. The photovoltaic power supply unit 2 is directly connected to the 48V low-voltage resistance wire of the DC heating component, while the mains power conversion and supplementary heating unit 3 and the mains power direct supply unit 4 are disconnected. The water in the integrated water storage and steam tank 11 is heated through the 48V low-voltage resistance wire. The heated hot water in the tank is output to the domestic water terminals such as bathrooms and kitchens through the hot water output pipe 13. The high-temperature steam generated in the integrated water storage and steam tank 11 is transported to the steam air conditioning terminal through the steam output pipe 14, realizing the simultaneous output of hot water and steam.

[0053] When the power generation is less than the preset power threshold, the control unit further judges the load demand. Specifically, if the load demand is lower than the preset load threshold, the AC power conversion and heating unit 3 is activated to convert the AC AC power into 48V DC power through the step-down and voltage stabilization module to supply power to the DC heating component; if the load demand is higher than or equal to the preset load threshold, the AC power direct supply unit 4 is activated to directly supply AC power to the AC heating component.

[0054] This application prioritizes photovoltaic DC direct-drive heating when photovoltaic power supply is sufficient, eliminating the need for inverters and helping to reduce power loss. When photovoltaic power is insufficient, it intelligently selects the supplementary heating path according to load demand. Under conditions of low electrical load demand, the mains power conversion supplementary heating unit 3 is activated as an auxiliary supplementary heating method. At this time, the load demand is small, and the conduction loss and switching loss of the rectification and step-down stage are within a controllable range, resulting in high supplementary power supply efficiency. Under conditions of high electrical load demand, the mains power direct supply unit 4 directly supplies power to the AC heating components, which helps to achieve a smooth transition and optimization of the device's efficiency under different operating conditions. This makes the device adaptable to residential, guesthouse, factory, hotel, and off-grid scenarios in high-altitude pastoral areas, enhancing the device's scenario adaptability and versatility.

[0055] This application also discloses a method for using a photovoltaic direct-drive integrated steam and hot water device, which uses the aforementioned integrated device and includes the following steps: Step S1: Collect the power generation of photovoltaic power supply unit 2 through the power acquisition module and feed it back to the control unit.

[0056] Step S2: The control unit executes a heating strategy based on the power generation of photovoltaic power supply unit 2 and the load demand, specifically, If the control unit receives a power generation of photovoltaic power supply unit 2 that is greater than or equal to the preset power threshold, it will connect the circuit between photovoltaic power supply unit 2 and DC heating component, so that the DC power generated by photovoltaic power supply unit 2 directly drives DC heating component to work. After the DC heating component is powered on, it heats the water in the integrated water storage and steam tank 11. The water temperature gradually rises to the set temperature, producing hot water and steam.

[0057] If the control unit receives a power output from photovoltaic power supply unit 2 that is lower than the preset power threshold, the control unit further determines the current load demand. If the control unit determines that the load demand is lower than the preset load threshold, it activates the AC power conversion and heating unit 3, which converts AC AC power to 48V DC power through a step-down and voltage-stabilizing module to supplement the power supply to the DC heating component and maintain the heating process. If the control unit determines that the load demand is higher than or equal to the preset load threshold, it activates the AC power direct supply unit 4, which directly supplies 220V AC power to the AC heating component to drive the AC heating component to heat.

[0058] Step S3: The temperature sensor detects the water temperature inside the integrated water storage and steam tank 11 and feeds it back to the control unit. After receiving the water temperature signal, the control unit compares it with the preset temperature threshold. When the water temperature reaches the preset temperature threshold, the control unit immediately cuts off the circuit connection between the photovoltaic power supply unit 2, the mains power conversion and supplementary heating unit 3, and the mains power direct supply unit 4 and the corresponding heating components, and stops heating.

[0059] Step S4: The high-temperature steam generated by the integrated steam and hot water generating unit 1 during the heating process is delivered to the steam air conditioning terminal through the steam output pipeline 14 to achieve winter heating or year-round constant temperature regulation; the generated hot water is directly supplied to domestic water terminals such as bathrooms and kitchens through the hot water output pipeline 13 to meet the domestic hot water needs for bathing, washing and other purposes.

[0060] Example 2:

[0061] Reference Figure 3 and Figure 4 The difference between this embodiment and embodiment 1 is that a partition 8 is fixedly installed inside the integrated water and steam storage box 11. Specifically, the partition 8 is vertically installed inside the integrated water and steam storage box 11, dividing the interior of the integrated water and steam storage box 11 into a heating chamber 9 and an evaporation chamber 10. The water inlet pipe 12 is connected to the upper end of the heating chamber 9, the hot water output pipe 13 is connected to the lower end of the heating chamber 9, the steam output pipe 14 is connected to the upper end of the evaporation chamber 10, and the safety valve 30 is installed in the evaporation chamber 10. The DC low-pressure heating pipe 5 of the DC heating component and the insulated heating pipe 6 of the AC heating component both pass through the partition 8, and their two ends extend into the heating chamber 9 and the evaporation chamber 10, respectively.

[0062] Reference Figure 3 and Figure 4 The partition 8 has multiple connecting holes 15, and is equipped with adjustment components for regulating the opening and closing degree of the connecting holes 15. Specifically, the connecting holes 15 are channels connecting the heating chamber 9 and the evaporation chamber 10, used to guide hot water and steam from the heating chamber 9 into the evaporation chamber 10. The number and distribution of the connecting holes 15 are rationally designed according to the volume and heat load of the integrated water storage and steam tank 11, and are usually evenly distributed on the partition 8. To further facilitate the full flow of steam from the heating chamber 9 into the evaporation chamber 10, steam passages can also be specially opened at the upper end of the partition 8.

[0063] Reference Figure 3 and Figure 4 To facilitate adjustment of the opening and closing degree of each connecting hole 15, the adjustment assembly includes a sealing body 16, a support spring 17, and a shape memory metal adjusting plate 18. The sealing body 16 corresponds one-to-one with the connecting hole 15. The sealing body 16 is slidably disposed on the side of the partition 8 near the evaporation chamber 10. The sliding direction of the sealing body 16 is parallel to the plane of the partition 8. The sealing body 16 is used to move towards or away from the corresponding connecting hole 15. Specifically, the sealing body 16 and the partition 8 can be guided by the cooperation of the slider and the slide groove, or by the cooperation of the slide rail and the slide seat, so that the sealing body 16 and the partition 8 will not separate, and also so that under water pressure, the sealing plate and the partition 8 will not slide relative to each other in the direction perpendicular to the plane of the partition 8.

[0064] Reference Figure 3 and Figure 4 The supporting spring 17 corresponds one-to-one with the sealing body 16. The extension direction of the supporting spring 17 is parallel to the sliding direction of the corresponding sealing body 16. One end of the supporting spring 17 is fixed to the partition plate 8, and the other end is fixed to the corresponding sealing body 16. When the supporting spring 17 is in its natural state, the partition plate 8 covers one side of the corresponding connecting hole 15, specifically covering more than three-quarters of the area of ​​the corresponding connecting hole 15. At this time, the connecting hole 15 is partially closed, reducing the flow area between the heating chamber 9 and the evaporation chamber 10, so as to ensure the steam generation effect in the evaporation chamber 10. When the sealing body 16 is away from the connecting hole 15, the connecting hole 15 is fully or partially opened, increasing the flow area, so as to improve the evaporation efficiency while ensuring the evaporation effect.

[0065] Reference Figure 3 and Figure 4The shape memory metal adjusting plate 18 corresponds to the sealing body 16. A support 19 is fixed to the side of the partition 8 near the evaporation chamber 10, with each support 19 corresponding to a shape memory metal adjusting plate 18. One end of each shape memory metal adjusting plate 18 is fixed to the support 19, and the other end abuts against the corresponding sealing body 16. The shape memory metal adjusting plate 18 is located on the side of the corresponding sealing body 16 away from the supporting spring 17. Furthermore, each sealing body 16 corresponds to two shape memory metal adjusting plates 18, located on both sides of the corresponding connecting hole 15. When the shape memory metal adjusting plate 18 is in its initial bent state, the sealing body 16 seals one side of the corresponding connecting hole 15. When the shape memory metal adjusting plate 18 extends to a straight state after the temperature rises, it pushes the corresponding sealing body 16 to move away from the connecting hole 15. The sum of the deformation thrust of the two shape memory metal adjusting plates 18 is greater than the elastic force of the supporting spring 17.

[0066] Shape memory alloys possess the characteristic of recovering a preset shape above a specific phase transition temperature and maintaining the deformed shape below the phase transition temperature. This characteristic of the shape memory metal regulating plate 18 allows it to straighten and push the sealing body 16 to move at the evaporation temperature, thereby expanding the open area of ​​each connecting hole 15 and controlling the water flow and steam flux between the heating chamber 9 and the evaporation chamber 10. In this embodiment, the shape memory metal regulating plate 18 is a two-way shape memory alloy, and its phase transition temperature is adapted to the water evaporation temperature. In this embodiment, the phase transition temperature range is 80-105°C, and near-equal atomic ratio NiTi alloys, nickel-titanium-hafnium superalloys, etc., can be used.

[0067] Reference Figure 3 and Figure 4 The drain pipe 29 is connected to the heating chamber 9 or the evaporation chamber 10. In this embodiment, the drain pipe 29 is connected to the heating chamber 9. The lower end of the partition 8 is provided with a drain hole 20 so that the sewage in the evaporation chamber 10 can flow to the heating chamber 9. A conical sealing plug 23 is slidably inserted on the partition 8. The diameter of the conical sealing plug 23 decreases from the heating chamber 9 toward the direction closer to the evaporation chamber 10. The maximum diameter of the conical sealing plug 23 is greater than the diameter of the drain hole 20, and the minimum diameter of the conical sealing plug 23 is less than the diameter of the drain hole 20.

[0068] Reference Figure 3 and Figure 4To prevent the conical sealing plug 23 from falling off the partition 8, two limiting strips 24 are fixed to the end face of the conical sealing plug 23 near the evaporation chamber 10. The distance between the two limiting strips 24 and their ends is greater than the diameter of the drain hole 20. When the limiting strips 24 abut against the side of the partition 8 near the evaporation chamber 10, the conical sealing plug 23 opens the drain hole 20; when the conical sealing plug 23 seals the drain hole 20, the limiting strips 24 disengage from the partition 8. Furthermore, to ensure that the conical sealing plug 23 is normally positioned to seal the drain hole 20, a push spring is provided between the limiting strips 24 and the partition 8. The push spring pushes the limiting strips 24, causing the conical sealing plug 23 to move towards the evaporation chamber 10. Furthermore, to facilitate the sliding of the conical sealing plug 23 and the limiting strips 24, a guide rod can also be fixed on the partition 8, with the limiting strips 24 slidably fitted onto the guide rod.

[0069] Reference Figure 3 , Figure 4 and Figure 5 During sewage discharge, the conical sealing plug 23 will be subject to water pressure difference and tend to move towards the direction closer to the heating chamber 9. To ensure that the conical sealing plug 23 can open the sewage discharge hole 20, a pulling component is provided in the sewage discharge pipe 29. The pulling component is located upstream of the valve body on the sewage discharge pipe 29. The pulling component is used to pull the conical sealing plug 23 to slide towards the direction closer to the heating chamber 9. Specifically, the pulling component includes mounting plate 26, sliding plate 27 and connecting rope 28. The mounting plate 26 is fixed to the inner walls of opposite sides of the sewage discharge pipe 29. The sliding plate 27 is slidably connected between the two mounting plates 26 through a guide rail. The sliding direction of the sliding plate 27 is parallel to the length direction of the sewage discharge pipe 29. The cross-sectional area of ​​the sliding plate 27 is much smaller than the cross-sectional area of ​​the sewage discharge pipe 29 and will not affect the sewage discharge. The connecting rope 28 is fixed on the side of the sliding plate 27 and the conical sealing plug 23 that is close to the heating chamber 9. The connecting rope 28 is made of steel wire rope. In other embodiments, the pulling assembly may also employ an impeller and a pull rope. The impeller is rotatably disposed inside the drain pipe 29. When the water flows in the drain pipe 29, it drives the impeller to rotate. One end of the pull rope is wound around the impeller shaft, and the other end is connected to the side of the conical sealing plug 23 near the heating chamber 9. By rotating the impeller, the pull rope is wound up, so that during sewage discharge, the pull rope can also pull the conical sealing plug 23 to slide towards the heating chamber 9, opening the drain hole 20.

[0070] The implementation principle of Embodiment 2 of this application is as follows: When the water temperature in the evaporation chamber 10 reaches the evaporation temperature, it also reaches the phase change temperature of the shape memory metal regulating plate 18. At this time, the shape memory metal regulating plate 18 extends from a bent state to a straight state, generating a large restoring force to push the sealing body 16 to move away from the corresponding connecting hole 15, compressing the support spring 17, increasing the opening of the connecting hole 15, and allowing a large amount of hot water in the heating chamber 9 to flow into the evaporation chamber 10, generating more steam to meet the heating demand while ensuring the evaporation effect.

[0071] When the water temperature in the evaporation chamber 10 is lower than the evaporation temperature, the steam generation effect is poor. At this time, the shape memory metal regulating plate 18 is in its initial bent state, and the sealing body 16, under the action of the supporting spring 17, blocks three-quarters or more of the corresponding connecting hole 15, reducing the amount of water entering the evaporation chamber 10. This ensures that the water in the evaporation chamber 10 quickly rises to a higher temperature to continuously generate steam, without easily affecting the continuous supply of steam. This application achieves automatic temperature control by utilizing the thermotropic deformation characteristics of the shape memory metal regulating plate 18. It can automatically adjust the opening and closing degree of the connecting hole 15 according to the water temperature change without the need for an external power source and control signal.

[0072] When the valve on the drain pipe 29 is closed and tap water is continuously supplied to the heating chamber 9 by the inlet pipe 12, the conical sealing plug 23, under the action of the water pressure in the heating chamber 9 and the action of the push spring, maintains the state of blocking the drain hole 20, and only relies on the connecting hole 15 to regulate the water volume in the heating chamber 9 and the evaporation chamber 10. When the valve on the drain pipe 29 is open and the draining operation is carried out, the water flowing through the drain pipe 29 impacts the sliding plate 27 and moves it a certain distance along the drain pipe 29. At this time, the impact force of the water on the sliding plate 27 is greater than the elastic force of the push spring and the water resistance encountered by the conical sealing plug 23. The conical sealing plug 23 is pulled towards the direction closer to the heating chamber 9 by the connecting rope 28, opening the drain hole 20, thereby realizing the synchronous draining of the heating chamber 9 and the evaporation chamber 10, without the need to set up two drain pipes 29 and valves.

[0073] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A photovoltaic direct-drive integrated steam and hot water device, characterized in that, include: The integrated steam and hot water generating unit (1) is used to connect to the external steam air conditioning and heating pipeline and the domestic water pipeline respectively; A DC heating component is installed in the integrated steam and hot water generation unit (1); An AC heating component is installed in the integrated steam and hot water generating unit (1); A photovoltaic power supply unit (2) is electrically connected to the DC heating component. The photovoltaic power supply unit (2) is used to convert solar energy into DC power and supply power to the DC heating component. The AC power conversion and heating unit (3) is electrically connected to the DC heating component. The AC power conversion and heating unit (3) is used to convert AC AC power into DC power and supply it to the DC heating component. The mains power supply unit (4) is electrically connected to the AC heating component, and the mains power supply unit (4) is used to supply power to the AC heating component; The control unit is electrically connected to the DC heating component, AC heating component, photovoltaic power supply unit (2), mains power conversion and heating unit (3), and mains power direct supply unit (4), respectively. When the power generation of the photovoltaic power supply unit (2) is lower than the preset power threshold, the control unit determines the load demand. If the control unit determines that the load demand is lower than the preset load threshold, it starts the mains power conversion and heating unit (3) to convert AC mains power into DC power to supply power to the DC heating component. If the control unit determines that the load demand is higher than or equal to the preset load threshold, it starts the mains power direct supply unit (4) to supply power to the AC heating component.

2. The photovoltaic direct-drive integrated steam and hot water device according to claim 1, characterized in that, The integrated steam and hot water generating unit (1) includes an integrated steam and water storage box (11), an inlet pipe (12), a hot water output pipe (13), and a steam output pipe (14). The inlet pipe (12), the hot water output pipe (13), and the steam output pipe (14) are all connected to the integrated steam and water storage box (11). The inlet pipe (12) is used to connect with an external water supply pipe, the hot water output pipe (13) is used to connect with a domestic water supply pipe, and the steam output pipe (14) is used to connect with an external steam air conditioning and heating pipe. The DC heating component and the AC heating component are both installed inside the integrated steam and water storage box (11).

3. The photovoltaic direct-drive integrated steam and hot water device according to claim 2, characterized in that, The integrated water and steam storage box (11) includes an outer shell (111), an insulation layer (112), and an inner liner (113) arranged sequentially from the outside to the inside. The DC heating component and the AC heating component are both installed in the inner liner (113). A drain pipe (29) is connected to the integrated water and steam storage box (11). A safety valve (30) is installed on the top of the integrated water and steam storage box (11).

4. The photovoltaic direct-drive integrated steam and hot water device according to claim 1, characterized in that, The DC heating assembly includes a DC low-voltage heating tube (5), and a 48V low-voltage resistance wire is installed inside the DC low-voltage heating tube (5).

5. The photovoltaic direct-drive integrated steam and hot water device according to claim 4, characterized in that, The AC heating assembly includes an insulated heating tube (6), and a leakage protection current limiting resistor (7) is connected in series at the inlet end of the insulated heating tube (6).

6. The photovoltaic direct-drive integrated steam and hot water device according to claim 1, characterized in that, The photovoltaic power supply unit (2) includes a photovoltaic panel (21) and an MPPT voltage regulator module (22), which is electrically connected to the photovoltaic panel (21) and the DC heating component respectively.

7. The photovoltaic direct-drive integrated steam and hot water device according to claim 1, characterized in that, The mains power conversion and heating unit (3) includes a step-down and voltage-stabilizing module, which is electrically connected to the AC mains power and is connected in parallel with the DC heating component.

8. The photovoltaic direct-drive integrated steam and hot water device according to claim 2, characterized in that, The integrated water and steam storage box (11) is equipped with a partition (8), which divides the integrated water and steam storage box (11) into a heating chamber (9) and an evaporation chamber (10). The water inlet pipe (12) and the hot water output pipe (13) are both connected to the heating chamber (9), and the steam output pipe (14) is connected to the evaporation chamber (10). The DC heating component and the AC heating component both extend through both ends of the partition (8) into the heating chamber (9) and the evaporation chamber (10) respectively. The partition (8) is provided with multiple connecting holes (15), and the partition (8) is provided with an adjustment component for adjusting the opening and closing degree of the connecting holes (15).

9. A photovoltaic direct-drive integrated steam and hot water device according to claim 8, characterized in that, The adjustment assembly includes a sealing body (16), a support spring (17), and a shape memory metal adjustment plate (18). The sealing body (16) corresponds one-to-one with the connecting hole (15). The sealing body (16) is slidably disposed on the partition plate (8). The sealing body (16) is used to move toward or away from the corresponding connecting hole (15). The support spring (17) is disposed on the partition plate (8). When the support spring (17) is in its natural state, the sealing body (16) blocks one side of the corresponding connecting hole (15). The shape memory metal adjusting piece (18) corresponds to the sealing body (16). The shape memory metal adjusting piece (18) is disposed between the partition (8) and the corresponding sealing body (16). When the shape memory metal adjusting piece (18) is in the initial bent state, the sealing body (16) blocks one side of the corresponding connecting hole (15). When the shape memory metal adjusting piece (18) stretches into a straight state after the temperature rises, the shape memory metal adjusting piece (18) pushes the corresponding sealing body (16) to move away from the connecting hole (15).

10. A method of using a photovoltaic direct-drive integrated steam and hot water device, comprising the integrated device as described in any one of claims 1-9, characterized in that, Includes the following steps: The power generation of the photovoltaic power supply unit (2) is collected by the power acquisition module and fed back to the control unit; The control unit receives the power generation power of the photovoltaic power supply unit (2) collected by the power acquisition module and compares it with the preset power threshold. If the power generation power of the photovoltaic power supply unit (2) is greater than or equal to the preset power threshold, the photovoltaic power supply unit (2) and the DC heating component are connected, so that the photovoltaic power supply unit (2) directly drives the DC heating component to heat the water in the integrated steam and hot water generation unit (1). The water in the integrated steam and hot water generation unit (1) generates hot water and steam after heating. If the power generation power of the photovoltaic power supply unit (2) is lower than the preset power threshold, the control unit continues to judge the load demand. If the control unit judges that the load demand is lower than the preset load threshold, the mains power conversion and heating unit (3) is started to convert AC mains power into DC power to supply DC heating component. If the control unit judges that the load demand is higher than or equal to the preset load threshold, the mains power direct supply unit (4) is started to supply AC heating component. A temperature sensor is used to detect the water temperature in the integrated steam and hot water generating unit (1) and feed it back to the control unit. When the control unit receives that the water temperature in the integrated steam and hot water generating unit (1) has reached the preset temperature threshold, the control unit cuts off the power supply circuit of the photovoltaic power supply unit (2), the mains power conversion and heating unit (3) and the mains power direct supply unit (4). The steam output from the integrated steam and hot water generating unit (1) is delivered to the steam air conditioning terminal to achieve heating, and the output hot water is directly supplied to domestic water use.

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