Heat preservation water tank liquid level control method and system of energy storage coupling heat pump

Abstract

The invention relates to the technical field of energy utilization and energy storage, and discloses a heat preservation water tank liquid level control method and system of an energy storage coupling heat pump, and the method comprises the steps that water is heated to a target temperature through a heat pump, and the water at the target temperature is stored through a heat preservation water tank; related data of the heat pump and the heat preservation water tank are monitored through a sensor; in combination with related data collected in real time and historical related data, a regression analysis algorithm and a time sequence analysis algorithm are used for data analysis, and predicted water flow at the first moment in the future is obtained through prediction; according to the predicted water flow and the heat supply capacity of the heat pump, the minimum heat storage water amount at least needing to be stored in the heat preservation water tank at the first moment is calculated; on the basis of the minimum heat storage water amount, the liquid level of the heat preservation water tank is controlled in a liquid level and temperature combined control mode; therefore, the water demand of the user is met.

Description

Technical Field

[0001] The present application relates to the field of energy utilization and energy storage technology, and in particular to a method and system for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump. Background Art

[0002] In the field of industrial heating technology, traditional combustion boilers are being replaced by technologies such as electric boilers that use clean energy due to their low efficiency and high carbon emissions. Among them, the utilization of energy storage systems has been greatly developed, especially the heating device of energy storage coupled heat pump, which combines the advantages of energy storage devices and heat pumps, so that the floor space and energy efficiency of the heating device are optimized. However, in the prior art, the control of the energy storage coupled heat pump heating device is still relatively simple, and there is room for optimization in terms of the coupling degree between the energy storage device and the heat pump device, the full utilization of valley electricity, and the capacity setting of the energy storage device. This is mainly reflected in the following aspects: First, in terms of the coupling control between the energy storage device and the heat pump device, the existing control technology has not been able to give full play to the synergistic effect of the two, resulting in the need to improve the operating efficiency of the overall system. Secondly, the current technology has not been able to fully tap the low-cost electricity resources during the valley electricity period, and cannot maximize the use of valley electricity to reduce the heating cost. Finally, in terms of the capacity setting of the energy storage device, the prior art generally ignores the control of the water storage capacity of the insulation water tank. If the water tank is in high liquid level operation for a long time, this may lead to excessive storage and waste of water resources. Or during peak water usage, if the water tank does not hold enough water, users may experience insufficient water pressure or water supply interruption, affecting their daily life and production. Summary of the invention

[0003] In order to solve the above technical problems, the present application discloses a method and system for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump, which calculates the minimum amount of hot water to be stored in the insulated water tank at the first moment according to the predicted water flow and the heating capacity of the heat pump; based on the minimum amount of hot water, the liquid level of the insulated water tank is controlled by a combined control method of liquid level and temperature to meet the water needs of users. Specifically, the technical solution of the present application is as follows:

[0004] In a first aspect, the present application discloses a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump, comprising the following steps:

[0005] The water is heated to a target temperature by a heat pump, and the water at the target temperature is stored in an insulated water tank; the relevant data of the heat pump and the insulated water tank are monitored by a sensor; the relevant data specifically include: temperature sensing data of the heat pump and the insulated water tank; flow sensing data and liquid level sensing data of the insulated water tank;

[0006] Combining the relevant data collected in real time with the historical relevant data, using regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future;

[0007] Calculating the minimum amount of hot water to be stored in the thermal insulation water tank at the first moment according to the predicted water flow rate and the heating capacity of the heat pump;

[0008] On the basis of the minimum hot water storage capacity, the liquid level of the thermal insulation water tank is controlled by a liquid level and temperature combined control method to meet the water demand of the user.

[0009] In some embodiments, the minimum amount of hot water to be stored in the thermal insulation water tank at the first moment is calculated by the following formula: Emin=F·T·(1+r);

[0010] Where: F is the predicted water flow of the system at the first moment, unit: m 3 / h; T is the time required for the heat pump to heat the water with flow rate F from the initial temperature to the target temperature, unit: h; r is the safety redundancy ratio, which is 10% to 20%.

[0011] In some embodiments, the heat pump includes at least a first heat pump and a second heat pump;

[0012] Also includes:

[0013] Using the first heat pump and / or the second heat pump to provide heat to the water in the thermal insulation water tank;

[0014] Based on the heating capacity of the heat pump, the preset priority and the heat demand of the thermal insulation water tank, the heating mode of the first heat pump and / or the second heat pump is controlled.

[0015] In some embodiments, the method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump further includes: calculating the heat demand of the insulated water tank at a first moment in combination with the predicted water flow rate and the predicted ambient temperature;

[0016] Specifically include:

[0017] Obtain weather forecast information for a specified time period in the future, including but not limited to temperature, humidity, and wind speed;

[0018] Use the pre-built thermal model, combined with the predicted ambient temperature conditions and the historical ambient temperature conditions, to predict the initial temperature of the water at the first moment;

[0019] The predicted water flow rate and the initial temperature are combined to calculate the heat demand of the thermal insulation water tank at the first moment.

[0020] In some embodiments, heat demand Q = F·ρ·c·Δt;

[0021] Where: F is the flow rate of water, unit: m 3 / h; ρ is the density of water, in kg / m 3 ; c is the specific heat capacity of water, in J / (kg·K); Δt is the temperature change, in °C;

[0022] Δt = target temperature - initial temperature.

[0023] In some embodiments, the controlling the heating mode of the first heat pump and / or the second heat pump further comprises:

[0024] calculating heating capacities of the first heat pump and the second heat pump respectively;

[0025] Determine whether the heating capacity of the first heat pump and / or the second heat pump can meet the heat demand.

[0026] In some embodiments, the target temperature is a value lower than the saturation temperature by a first set temperature difference;

[0027] The saturation temperature is affected by the pressure in the insulated water tank; when the heating temperature of the heat pump exceeds the boiling point of water, the pressure in the insulated water tank is adjusted to control the value of the saturation temperature; within a specified range, the higher the pressure, the higher the saturation temperature;

[0028] The first set temperature difference is 2-10°C.

[0029] In some embodiments, the first heat pump is a waste heat heat pump; and the second heat pump is an air source heat pump.

[0030] In some embodiments, based on the minimum amount of hot water stored, the liquid level of the thermal insulation water tank is controlled by a combined liquid level and temperature control method; further comprising:

[0031] Obtaining a current first water storage capacity of the thermal insulation water tank and a first temperature in the thermal insulation water tank;

[0032] When the first water storage capacity is less than the minimum hot water storage capacity, and the first temperature is not less than the water replenishment temperature set by the system, the heat pump water replenishment function is automatically started to replenish the thermal insulation water tank; and the operation is automatically stopped after the liquid level in the thermal insulation water tank reaches the upper limit of the liquid level set by the system;

[0033] The second temperature in the insulated water tank after water replenishment is obtained. When the second temperature is lower than the upper limit of the water temperature set by the system, a heating start signal is output to the heat pump so that the heat pump automatically starts to perform cyclic heating until the second temperature reaches the upper limit of the water temperature and stops.

[0034] In some embodiments, the method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump further includes:

[0035] The real-time flow rate of the thermal insulation water tank is monitored by a flow sensor; when the real-time flow rate of the thermal insulation water tank is greater than the predicted water flow rate at the first moment, the thermal insulation water tank is supplementarily heated;

[0036] Specifically including: supplementary heating by electric heating method;

[0037] Or, supplementary heating is performed by heating the molten salt tank by first releasing heat;

[0038] Alternatively, supplementary heating can be provided by first releasing heat from a molten salt storage tank to supply heat to a heat pump.

[0039] In some embodiments, the maximum heating temperature of the first heat pump is the value of the lowest working temperature of the molten salt storage tank for generating steam minus the second set temperature difference, and the second set temperature difference is 10-50°C.

[0040] In a second aspect, the present application also discloses a heat storage coupled heat pump insulated water tank liquid level control system, including a heat pump, an insulated water tank, a sensor module, and a processor module;

[0041] The heat pump is connected to the thermal insulation water tank and is used to provide heat for the water in the thermal insulation water tank;

[0042] The sensor module is used to monitor the relevant data of the heat pump and the insulated water tank; the relevant data specifically includes: temperature sensing data of the heat pump and the insulated water tank; flow sensing data and liquid level sensing data of the insulated water tank;

[0043] The processor module is used to combine the relevant data collected in real time and the historical relevant data, use regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future;

[0044] The processor module is also used to calculate the minimum amount of hot water to be stored in the insulated water tank at the first moment based on the predicted water flow and the heating capacity of the heat pump; based on the minimum amount of hot water, control the liquid level of the insulated water tank by a combined level and temperature control method to meet the user's water demand.

[0045] In some embodiments, the heat pump includes at least a first heat pump and a second heat pump; the first heat pump and / or the second heat pump are used to provide heat for the water in the thermal insulation water tank;

[0046] The processor module is further used to calculate the heat demand of the thermal insulation water tank at the first moment by combining the predicted water flow rate and the predicted ambient temperature;

[0047] The processor module is also used to control the heating mode of the first heat pump and / or the second heat pump based on the heating capacity of the heat pump, the preset priority and the heat demand of the insulated water tank.

[0048] In some embodiments, the energy storage coupled heat pump insulated water tank level control system further includes: a water replenishment module connected to the sensor module;

[0049] The sensor module includes a liquid level sensor for obtaining the current first water storage volume of the thermal insulation water tank; and a temperature sensor for obtaining the current first temperature in the thermal insulation water tank;

[0050] The water replenishment module is further used to automatically start the heat pump water replenishment function to replenish the thermal insulation water tank when the first water storage capacity is less than the minimum hot water storage capacity and the first temperature is not less than the water replenishment temperature set by the system; and automatically stop after detecting that the liquid level in the thermal insulation water tank reaches the liquid level upper limit set by the system;

[0051] The temperature sensor is also used to obtain the second temperature in the thermal insulation water tank after water replenishment;

[0052] The sensor module further includes a signal transceiver submodule, which is used to output a heating start signal to the heat pump when the second temperature is lower than the upper limit of the water temperature set by the system;

[0053] The heat pump is also used to automatically start cyclic heating after receiving the heating start signal and stop after the second temperature reaches the water temperature upper limit.

[0054] In some embodiments, the energy storage coupled heat pump insulated water tank level control system further includes: a supplementary heating module;

[0055] The sensor module also includes a flow sensor for monitoring the real-time flow of the thermal insulation water tank;

[0056] The supplementary heating module supplements heating of the thermal insulation water tank when the real-time flow of the thermal insulation water tank at the first moment is greater than the predicted water flow;

[0057] The supplementary heating module specifically includes: an electric heating module and / or a molten salt storage tank heating module.

[0058] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0059] 1. This application determines the minimum water storage capacity through the heating capacity of the heat pump and the user's required flow rate, reduces the water storage space, and avoids waste caused by unused water after storage. Calculating the minimum hot water storage capacity of the insulated water tank helps to rationally plan the storage and use of water resources. To ensure the stability of the water supply system, the calculation of the minimum water storage capacity provides a scientific basis for the design of the water supply system. It can also guide the size design of the water tank, the selection of the heating equipment, the layout of the piping system, etc., to ensure that the entire water supply system meets the needs, avoids the water tank being too large, and has the highest operating efficiency.

[0060] 2. Based on the minimum amount of hot water stored, this application uses a combined level and temperature control method to control the liquid level of the insulated water tank to meet the user's water demand. The liquid level control method of this application ensures that the water tank can meet the user's water demand during peak water use or emergencies, avoids water supply interruptions due to insufficient water, and ensures the user's water safety. At the same time, it can also avoid idle resources due to excessive water. The combined level and temperature control also reduces the waste of thermal energy, energy consumption and operating costs.

[0061] 3. This application gives priority to heating water to the target temperature through a heat pump, storing the water at the target temperature in an insulated water tank, and supplementing it with electric heating or molten salt heating when there is a peak demand for water consumption that deviates from the predicted value. The heat pump system efficiently utilizes waste heat sources or air sources, reducing dependence on electricity or molten salt energy, thereby reducing carbon emissions. Make full use of the high energy efficiency of the heat pump and expand the heating range of the heat pump, thereby further improving the overall energy efficiency ratio (COP, Coefficient of Performance) of the system. The heat pump is coupled with an electric heating or molten salt storage tank system to absorb excess steam heat from the molten salt storage tank system or waste heat from renewable energy, thereby improving energy efficiency and further reducing energy costs.

[0062] 4. This application combines the advantages of energy storage devices and heat pumps, and realizes the energy storage coupling of the two. The heat pump system is used in combination with electric heating or molten salt system, and the heating range of the heat pump and the heating / heat release range of the molten salt are coupled (molten salt can release heat to below 100°C, molten salt waste heat can be used for water source heat pumps, and heat pump valley electricity can be used to preheat molten salt). It can be efficiently used during valley power periods or when renewable energy is in surplus, fully tapping the low-cost electricity resources during valley power periods, maximizing the use of valley electricity to reduce heating costs, improve system energy efficiency and reduce the use of molten salt. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The preferred implementation scheme will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present application.

[0064] Figure 1This is a flowchart of an embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump in the present application;

[0065] Figure 2 This is a schematic diagram of the connection structure of an embodiment of a thermal insulation water tank level control system of an energy storage coupled heat pump in the present application;

[0066] Figure 3 This is a flowchart of another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to the present application;

[0067] Figure 4 This is a flowchart of another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to the present application;

[0068] Figure 5 This is a system block diagram of an embodiment of an insulated water tank level control system of an energy storage coupled heat pump in the present application.

[0069] Figure 6 This is a schematic diagram of the connection structure of another embodiment of a thermal insulation water tank level control system of an energy storage coupled heat pump in the present application;

[0070] Figure 7 This is a schematic structural diagram of a molten salt storage tank module with an inner cylinder in another embodiment of an insulated water tank level control system of an energy storage coupled heat pump in the present application.

[0071] 10—processor module, 20—heat pump unit, 30—insulated water tank, 40—sensor module, 50—molten salt storage tank, 60—steam cylinder, 70—desuperheater. DETAILED DESCRIPTION

[0072] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0073] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or collections.

[0074] In order to simplify the drawings, only the parts related to the invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0075] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0076] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0077] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0078] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the specific implementation methods of the present application will be described below with reference to the accompanying drawings. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0079] In the field of industrial heating technology, traditional combustion boilers have relatively low energy efficiency and large carbon emissions, which makes it difficult to meet the needs of modern society for efficient and low-carbon heating, and puts great pressure on the environment. Against this background, emerging technologies such as electric boilers that use clean energy have emerged. These technologies can not only effectively reduce carbon emissions, but also improve energy efficiency. In particular, the heating device of energy storage coupled heat pump combines the advantages of energy storage device and heat pump, realizing the organic combination of the two. In this way, the heating device has been significantly optimized in terms of floor space and energy efficiency, which not only saves space resources, but also improves energy efficiency, providing a more efficient and environmentally friendly solution for industrial heating.

[0080] However, although the energy storage coupled heat pump heating device has made certain technical progress, in the existing technology, the control strategy of the energy storage coupled heat pump heating device is still relatively simple, and the capacity configuration has not been accurately performed according to the actual heating demand and operating conditions, and there are certain limitations. This is mainly reflected in the following aspects: First, in terms of the coupling control between the energy storage device and the heat pump device, the existing control technology has not been able to fully exert the synergistic effect of the two, resulting in the operating efficiency of the overall system still needs to be improved. Secondly, the current technology has not been able to fully tap the low-cost electricity resources during the valley power period, and it is impossible to maximize the use of valley power to reduce the heating cost. Finally, in terms of the capacity setting of the energy storage device, the existing technology generally ignores the control of the water storage capacity of the insulation water tank. If the water tank is in high liquid level operation for a long time, this may lead to excessive storage and waste of water resources. Or during the peak water use period, if the water tank is insufficient, users may encounter insufficient water pressure or water supply interruption, affecting daily life and production.

[0081] In order to optimize the storage capacity and temperature control of the insulated water tank and realize efficient and stable operation of the system, the present application provides an insulated water tank level control method and system for an energy storage-coupled heat pump. The control method designed in combination with heat pump heating only requires the necessary minimum amount of hot water, and cooperates with dynamic adjustment and redundant design strategies, as well as a method of joint control of the tank liquid level and temperature, to improve the system energy efficiency while ensuring that the hot water flow and temperature requirements can still be met under extreme conditions.

[0082] Reference Manual Attached Figure 1 As shown, an embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump in the present application specifically includes the following steps:

[0083] S100, heating water to a target temperature through a heat pump, and storing water at the target temperature through an insulated water tank; monitoring relevant data of the heat pump and the insulated water tank through sensors; the relevant data specifically include: temperature sensing data of the heat pump and the insulated water tank; flow sensing data and liquid level sensing data of the insulated water tank.

[0084] For details, please refer to the attached manual. Figure 2 As shown, the energy storage coupled heat pump heating device of the present application includes a heat pump and an insulated water tank, as well as pipes and valve groups, and an energy storage module coupled to the heat pump. The heat pump is used to heat water and store it in the insulated water tank. The high-temperature water stored in the insulated water tank is used to provide hot water for the molten salt module (or other energy storage module) to generate high-temperature steam during the steam demand period.

[0085] In order to give full play to the energy efficiency advantages of heat pumps, this application uses heat pumps to prepare high-temperature water slightly below the saturation temperature. The saturation temperature of water refers to the temperature when water reaches a saturated state (that is, liquid water and water vapor are in a dynamic equilibrium state) under a certain pressure. The saturation temperature is closely related to pressure. The higher the pressure, the higher the saturation temperature; the lower the pressure, the lower the saturation temperature. The high-temperature water is slightly lower than the saturation temperature, so that the water temperature is controlled at a high temperature but not boiling state, which can avoid the loss of latent heat of vaporization caused by boiling, thereby improving the transfer efficiency of thermal energy. It also avoids overheating, thereby reducing unnecessary energy waste.

[0086] The sensors include but are not limited to temperature sensors, flow sensors, liquid level sensors, time sensors, etc. They are used to collect temperature sensing data of the heat pump and the thermal insulation water tank, flow sensing data and liquid level sensing data of the thermal insulation water tank.

[0087] S200, combining the relevant data collected in real time and the historical relevant data, using regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future.

[0088] Specifically, during operation, the relevant parameters are acquired using dynamic adjustment strategies to cope with actual changes. The strategies include real-time monitoring and data collection, data analysis and prediction. Flow sensors that monitor the actual hot water usage, temperature sensors that monitor the temperature changes of the heat pump and the water tank, and level sensors that monitor the current liquid level of the water tank are required; based on this, water usage patterns and peak demands are identified. And algorithms such as regression analysis and time series analysis are used to predict future water consumption and heating needs. Then, based on real-time monitoring data and prediction models, the predicted water flow F at the first moment in the future is dynamically generated.

[0089] Better yet, establish a regression analysis model to handle the relationship between water consumption and other variables. Establish a time series analysis model to focus on the change of water consumption over time. Combine the external features in the regression analysis (such as temperature, humidity, wind direction) with the time series features (such as seasonality and trend) and input them into the time series model. Use ensemble learning methods (such as random forests and XGBoost) to combine the prediction results of multiple regression and time series models. Use convolutional neural networks to extract features and combine them with least squares support vector machines for regression prediction.

[0090] S300, calculating the minimum amount of hot water to be stored in the thermal insulation water tank at a first moment according to the predicted water flow rate and the heating capacity of the heat pump.

[0091] Specifically, in order to improve the energy efficiency and economic benefits of the system, the present application sets the minimum hot water volume (curve) of the insulated water tank at a certain moment according to the heating capacity of the heat pump and the predicted hot water usage flow (curve).

[0092] Specifically, the minimum amount of hot water to be stored in the thermal insulation water tank at the first moment is calculated by the following formula: Emin=F·T·(1+r).

[0093] Where: F is the predicted water flow of the system at the first moment, unit: m 3 / h; T is the time required for the heat pump to heat the water with flow rate F from the initial temperature to the target temperature, unit: h; r is the safety redundancy ratio, which is 10% to 20%.

[0094] Although the insulation performance of the insulated water tank is good, there will still be a certain amount of heat loss. If the water tank is too large, it means that more heat needs to be maintained, which will increase the energy consumption of the heating system. By calculating the minimum water storage capacity, it is possible to avoid the water tank being too large, reduce unnecessary heat maintenance, and reduce energy consumption and operating costs. It also helps to rationally plan the storage and use of water resources, and reduce the carbon emissions of the heating system by reducing unnecessary energy consumption.

[0095] S400, based on the minimum hot water storage amount, the liquid level of the thermal insulation water tank is controlled by a liquid level and temperature combined control method to meet the water demand of the user.

[0096] Specifically, on the basis of ensuring the minimum amount of hot water storage, the system uses a combined level and temperature control method to control the water tank level, effectively ensuring the water tank level while ensuring the water supply temperature. When the hot water level in the water tank is lower than the water replenishment level designed by the system, and the water temperature in the water tank reaches the water replenishment temperature set by the system, the system will automatically start the heat pump water replenishment function to replenish the water tank until the liquid level in the water tank reaches the upper limit of the water replenishment level set by the system and then automatically stop.

[0097] The system uses a heat pump directly connected to the insulated water tank. When the water tank temperature is more than 5°C lower than the upper limit of the water temperature set by the system, the heat pump unit automatically starts circulating heating through the water tank temperature sensor sensing the output of the start heating signal. After the water temperature in the water tank reaches the upper limit of the water temperature set by the system, the water tank temperature sensor outputs a stop heating signal, and the unit is instructed to automatically stop heating.

[0098] Based on the above embodiments, the present application discloses another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump, and the heat demand of the insulated water tank at a certain moment is calculated by the following formula.

[0099] Heat demand: Q = F·ρ·c·Δt.

[0100] Where: F is the flow rate of water, unit: m 3 / h; ρ is the density of water, in kg / m 3; c is the specific heat capacity of water, unit is J / (kg·K); Δt is the temperature change, unit is ℃.

[0101] Δt = target temperature - initial temperature.

[0102] Specifically, the target temperature is the temperature of high-temperature water. The target temperature is a value lower than the first set temperature difference of the saturation temperature; the saturation temperature is affected by the pressure in the thermal insulation water tank; when the heating temperature of the heat pump exceeds the boiling point of water, the pressure in the thermal insulation water tank is adjusted to control the value of the saturation temperature; within the specified range, the higher the pressure, the higher the saturation temperature.

[0103] The first set temperature difference is 2 to 10°C, preferably 4 to 8°C.

[0104] Taking the saturation temperature of water at 100°C under normal atmospheric pressure as an example, the target temperature is 90-98°C, preferably 95°C. The first set temperature difference is determined according to the process level and control capability. In order to further give full play to the energy efficiency advantages of the heat pump, when the maximum heating capacity of the heat pump is higher than 100°, the insulated water tank is pressurized, and its pressure setting corresponds to "the maximum heating capacity of the heat pump + the first set temperature difference". At this time, the heat pump still prepares high-temperature water slightly lower than the saturation temperature. For example, under pressurized conditions, the saturation temperature of water is 110°C, so the target temperature can be 105°C at this time.

[0105] The initial temperature of water is affected by external factors. For example, air temperature is one of the most direct factors affecting outdoor water temperature. An increase or decrease in air temperature will cause the water temperature to change accordingly. Altitude, humidity, wind speed, solar radiation, etc. will also affect the initial temperature.

[0106] In one implementation of this embodiment, the initial temperature defaults to a specified temperature value.

[0107] In another implementation of this embodiment, by obtaining weather forecast information within a specified time period in the future, including but not limited to temperature, humidity, and wind speed, a pre-built thermal model is used to predict the initial temperature of water at the first moment in combination with the predicted ambient temperature conditions and the historical ambient temperature conditions.

[0108] It also includes: combining the predicted water flow rate and the initial temperature to calculate the heat demand of the insulated water tank at the first moment.

[0109] Specifically, the initial temperature of the water and the time required for heating are continuously monitored through temperature sensors and time sensors. Obtain weather forecast information for the next 24 to 72 hours from a meteorological service provider, including but not limited to temperature, humidity, wind speed, etc. Input these data into a preset model that can predict the initial temperature of the water based on historical data and current environmental conditions, and can predict the heat demand of the insulated water tank at the first moment in the future (the total heat required to heat water with a flow rate of F from the initial temperature to the target temperature). Combined with the algorithm or model, predict the time T required for the heat pump to heat water with a flow rate of F from the initial temperature to the target temperature (high temperature water) at the first moment in the future, so as to reflect the heating capacity of the heat pump.

[0110] On the basis of the above-mentioned embodiments, the present application discloses another embodiment of a method for controlling a liquid level of an insulated water tank of an energy storage coupled heat pump, wherein the heat pump comprises at least a first heat pump and a second heat pump.

[0111] In this embodiment, a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump is provided. Figure 3 As shown, it also includes:

[0112] S110: Use the first heat pump and / or the second heat pump to provide heat for the water in the thermal insulation water tank.

[0113] S210: Controlling a heating mode of the first heat pump and / or the second heat pump based on the heating capacity of the heat pump, a preset priority, and a heat demand of the thermal insulation water tank.

[0114] Specifically, similar to the above embodiment, step S211 is first executed to calculate the heat demand of the insulated water tank at the first moment in combination with the predicted water flow rate and the predicted ambient temperature.

[0115] The method then further includes the step: S212, respectively calculating the heating capacity of the first heat pump and the second heat pump.

[0116] S213: Determine whether the heating capacity of the first heat pump and / or the second heat pump can meet the heat demand.

[0117] In this embodiment, the first heat pump is a waste heat heat pump; the second heat pump is an air source heat pump.

[0118] In one implementation of this embodiment, the waste heat heat pump is preset to have the highest priority. The heating capacity of the waste heat heat pump is reflected by the temperature of the waste heat heat pump.

[0119] Detect the temperature of the waste heat source. If the waste heat temperature is high enough and stable, the waste heat heat pump is used first to improve the energy efficiency ratio. If the waste heat temperature is low or unstable, it is necessary to use the waste heat heat pump in combination with the air source heat pump to maintain the stability of the water temperature in the insulated water tank. Specifically, in this embodiment, the waste heat heat pump is used for heating first. By judging whether the temperature of the waste heat heat pump exceeds the third temperature, it is judged whether the heating capacity can meet the heat demand. In this way, it is judged whether to enable the air source heat pump. Among them, the value of the third temperature represents whether the waste heat heat pump has enough heat energy to heat the water with a flow rate of F to the target temperature within a unit time. If the temperature of the waste heat heat pump exceeds the third temperature, the waste heat heat pump is used; if the temperature of the waste heat heat pump does not exceed the third temperature, the air source heat pump is enabled at the same time as the waste heat heat pump is enabled.

[0120] In another implementation of this embodiment, the waste heat heat pump is preset to have the highest priority, and the heating capacity of the waste heat heat pump is reflected by the total amount of heat that the waste heat heat pump can provide per unit time.

[0121] Determine whether the total heat provided by the waste heat heat pump per unit time can meet the heat demand. If it can, use the waste heat heat pump to improve the energy efficiency ratio. If the heating capacity of the waste heat heat pump cannot meet the heat demand, it is necessary to use the waste heat heat pump in combination with the air source heat pump to maintain the stability of the water temperature in the insulation water tank.

[0122] In another implementation of this embodiment, the air source heat pump is preset to have the highest priority, and the heating capacity of the air source heat pump is reflected by predicting the temperature.

[0123] The air source heat pump consumes a small amount of electricity to drive the compressor to compress the low-temperature and low-pressure refrigerant into a high-temperature and high-pressure gas. Then, the refrigerant releases heat in the condenser and transfers the heat to water or other media to achieve heating. After that, the refrigerant is reduced in pressure and temperature through the expansion valve, becomes a low-temperature and low-pressure liquid, and then enters the evaporator to absorb heat from the air to complete a cycle. The performance of the air source heat pump is closely related to the temperature. Changes in temperature will directly affect its heating or cooling efficiency, energy consumption and operational stability. At higher ambient temperatures (such as above 10°C), the air source heat pump can absorb heat from the air more efficiently, with higher heating efficiency and higher energy efficiency ratio (Coefficient of Performance, COP) value. When the temperature drops, the heat in the air decreases, the evaporation temperature drops, and the suction pressure of the compressor decreases, resulting in a decrease in heating capacity. In this embodiment, the heating capacity of the air source heat pump is reflected by predicting the temperature. Weather forecast data can be used to adjust the heating power of the air source heat pump in real time through the control system. Different modes of operation of the air source heat pump are set according to different external temperature ranges. For example:

[0124] When the outside temperature is above 10°C, the air source heat pump runs at full power.

[0125] When the outside temperature is between 5℃ and 10℃, the air source heat pump runs at 70% power.

[0126] When the outside temperature is below 5°C, the air source heat pump operates at the lowest efficiency or stops operating, relying more on molten salt heat storage.

[0127] In some other implementations of this embodiment, the time T required for the heat pump (the first heat pump or the second heat pump) to heat water with a flow rate F from an initial temperature to a target temperature reflects the heating capacity of the heat pump.

[0128] Among them, it is judged whether the heating capacity of the heat pump can meet the heat demand, that is, whether the heating time T exceeds the unit time. The water flow rate is in cubic meters per hour (m 3 / h) refers to the volume of water passing through a certain cross section per unit time. Specifically, flow rate F indicates how many cubic meters of water pass through the outlet pipe per hour. If the heating time does not exceed 1 hour per unit time, it means that its heating capacity meets the heat demand, and the first heat pump is used first to improve the energy efficiency ratio; if the heating time exceeds 1 hour per unit time, it means that the heating capacity of the first heat pump cannot meet the heat demand, and the second heat pump is activated while the first heat pump is activated.

[0129] In some other implementations of this embodiment, the heating power or COP of the heat pump (the first heat pump or the second heat pump) reflects the heating capacity of the heat pump. It is judged whether the heating capacity of the heat pump can meet the heat demand, that is, whether the real-time heating power exceeds the expected power; or whether the COP exceeds the expected COP.

[0130] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. For example, other types of related parameters can be used as the embodiment of the heating capacity of the heat pump, or other types of heat pumps can be used as the first / second heat pump; or a third heat pump can be added on the basis of the first / second heat pump, and the connection mode of the heat pump is series coupling or parallel coupling; and on this basis, the priority of the first, second or third heat pump can be selected and set. In this way, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

[0131] The present application discloses another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump. On the basis of the above embodiment, after judging whether the heating capacity of the heat pump can meet the heat demand, it also includes S214, which controls the heating mode of the first heat pump and / or the second heat pump in combination with the judgment result of step S213.

[0132] For example, the use priority of the first heat pump is set to be higher than the use priority of the second heat pump. When the heat demand = 80% of the heating capacity of the first heat pump, the first heat pump operates at 80% of the power.

[0133] When heat demand = 100% heating capacity of the first heat pump + 50% heating capacity of the second heat pump, the first heat pump operates at 100% power and the second heat pump operates at 50% power.

[0134] The present application provides another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump. Based on any one of the embodiments of the above method, the step S400 controls the liquid level of the insulated water tank by a combined liquid level and temperature control method based on the minimum amount of stored hot water; and further includes:

[0135] S410, obtaining a current first water storage capacity of the thermal insulation water tank and a first temperature inside the thermal insulation water tank.

[0136] S420, when the first water storage capacity is less than the minimum hot water storage capacity and the first temperature is not less than the water replenishment temperature set by the system, the heat pump water replenishment function is automatically started to replenish the insulated water tank; and the heat pump automatically stops after detecting that the liquid level in the insulated water tank reaches the upper limit of the liquid level set by the system.

[0137] S430, obtaining the second temperature in the insulated water tank after water replenishment, and when the second temperature is lower than the upper limit of the water temperature set by the system, outputting a heating start signal to the heat pump so that the heat pump automatically starts to perform cyclic heating until the second temperature reaches the upper limit of the water temperature and stops.

[0138] Specifically, the system uses a combined level and temperature control method to control the water tank level, effectively ensuring the water tank level while ensuring the water supply temperature. When the hot water level in the water tank is lower than the water replenishment level designed by the system, and the water temperature in the water tank reaches the water replenishment temperature set by the system, the system will automatically start the heat pump water replenishment function to replenish the water tank until the liquid level in the water tank reaches the upper limit of the water replenishment level set by the system and then automatically stop.

[0139] The system uses a heat pump directly connected to the insulated water tank. When the water tank temperature is more than 5°C lower than the upper limit of the water temperature set by the system, the heat pump unit automatically starts the heating cycle through the water tank temperature sensor. When the water temperature in the water tank reaches the upper limit of the water temperature set by the system, the water tank temperature sensor outputs a stop heating signal, and the unit is instructed to automatically stop heating. Preferably, the upper limit of the water temperature is the target temperature to which the heat pump heats the water;

[0140] The present application provides another embodiment of a method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump. Based on any one of the above embodiments, refer to the attached specification. Figure 4 Also shown is: Supplemental heating.

[0141] S500, monitoring the real-time flow of the insulated water tank through a flow sensor; when the real-time flow of the insulated water tank at the first moment is greater than the predicted water flow, supplementary heating is performed on the insulated water tank.

[0142] Specifically including: S510, performing supplementary heating by an electric heating method.

[0143] Or, S520, supplementary heating is performed by a molten salt storage tank heating method that first releases heat.

[0144] Or, S530, supplementary heating is performed by first releasing heat from the molten salt storage tank to provide heat for the heat pump.

[0145] Specifically, when there is a peak demand that deviates from the predicted value, the insulated water tank can be supplemented with electric heating, or supplemented with molten salt heating, or when a waste heat heat pump is used, the molten salt module can be used to supply heat to the waste heat heat pump, thereby improving the heating capacity of the waste heat heat pump and shortening the heating time T. Specifically, the molten salt module includes a plurality of molten salt storage tanks, some of which release heat first, and the remaining molten salt storage tanks release heat in sequence. The molten salt storage tank that releases heat first can provide preheating for the molten salt storage tank that releases heat later, and can also provide heating function for the insulated water tank, and even provide preheating for the waste heat heat pump, so that the molten salt storage tank can achieve deep heat release.

[0146] At the peak of water demand, the real-time flow rate of the insulated water tank may be greater than the predicted water flow rate. At this time, since the actual flow rate F' exceeds the predicted value F, the minimum hot water storage capacity Emin = F·T·(1+r) will not be able to continuously meet the demand. At this time, electric heating or the molten salt storage tank that releases heat first can be used to provide heating for the waste heat heat pump.

[0147] In order to simplify the device and achieve the above-mentioned temperature rise capacity, the system adopts open heating of transcritical carbon dioxide heat pump, and cyclic heating is performed only as needed. The maximum heating temperature of the waste heat heat pump is the lowest working temperature of the molten salt module for generating steam minus the value of the second set temperature difference. Specifically, in order to better couple the heat pump and the molten salt module, the maximum heating capacity of the heat pump is selected according to the lowest working temperature of the molten salt module for generating steam minus the second set temperature difference. The second set temperature difference is 10 to 50°C, and the second set temperature difference is preferably 20 to 40°C.

[0148] Based on the same concept, the present application also discloses a heat storage coupled heat pump insulated water tank liquid level control system. The system is used to implement the steps described in any of the above method embodiments. Figure 5 As shown, an embodiment of a liquid level control system of an insulated water tank of an energy storage coupled heat pump in the present application specifically includes:

[0149] Processor module 10 , heat pump 20 , thermal insulation water tank 30 , sensor module 40 .

[0150] The heat pump is connected to the thermal insulation water tank and is used to provide heat for the water in the thermal insulation water tank.

[0151] The sensor module is used to monitor the relevant data of the heat pump and the insulated water tank. The sensor module specifically includes: a temperature sensor, a flow sensor and a liquid level sensor. The relevant data specifically includes: temperature sensing data of the heat pump and the insulated water tank, flow sensing data of the insulated water tank and liquid level sensing data.

[0152] The processor module is used to combine the relevant data collected in real time and the historical relevant data, use regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future.

[0153] The processor module is further configured to calculate the minimum amount of hot water to be stored in the thermal insulation water tank at the first moment according to the predicted water flow rate and the heating capacity of the heat pump. Based on the minimum amount of hot water, the liquid level of the thermal insulation water tank is controlled by a combined liquid level and temperature control method to meet the user's water demand.

[0154] like Figure 2 As shown, the device of the present application includes the heat pump unit 20 and the insulated water tank 30 in the system, as well as related pipes and valve groups. In order to optimize the storage capacity and temperature control of the insulated water tank and realize efficient and stable operation of the system, a control method combining heat pump heating is designed, which only requires the minimum amount of hot water, and cooperates with dynamic adjustment and redundant design strategies, as well as a method of joint control of the tank liquid level and temperature, to improve the energy efficiency of the system while ensuring that the hot water flow and temperature requirements can still be met under extreme conditions.

[0155] During operation, the relevant parameters are acquired using dynamic adjustment strategies to cope with actual changes. The strategies include real-time monitoring and data collection, data analysis and prediction. Flow sensors that monitor the actual hot water usage, temperature sensors that monitor the temperature changes of the heat pump and water tank, and level sensors that monitor the current liquid level of the water tank are required; based on this, water usage patterns and peak demands are identified. And algorithms such as regression analysis and time series analysis are used to predict future water consumption and heating needs. Then, based on real-time monitoring data and prediction models, the predicted water flow F at the first moment in the future is dynamically generated.

[0156] The minimum amount of hot water to be stored in the thermal insulation water tank at the first moment is calculated by the following formula: Emin=F·T·(1+r).

[0157] Where: F is the predicted water flow of the system at the first moment, unit: m 3 / h; T is the time required for the heat pump to heat the water with flow rate F from the initial temperature to the target temperature, unit: h; r is the safety redundancy ratio, which is 10% to 20%.

[0158] Preferably, the processor module uses a combined level and temperature control method to control the water tank liquid level, effectively ensuring the water tank liquid level while ensuring the water supply temperature. When the hot water level in the water tank is lower than the system-designed water replenishment level or the aforementioned minimum hot water storage, and the water temperature in the water tank reaches the system-set water replenishment temperature, the system will automatically start the heat pump water replenishment function to replenish the water tank until the liquid level in the water tank reaches the system-set upper limit of the water replenishment level and then automatically stops. The system uses a heat pump directly connected to the insulated water tank. When the water tank temperature is more than 5°C lower than the system-set water temperature, the heat pump unit automatically starts circulating heating through the water tank temperature sensor to sense and output a start heating signal until the water temperature in the water tank reaches or slightly exceeds the system-set water tank temperature. The water tank temperature sensor outputs a stop heating signal, and the unit is instructed to automatically stop heating.

[0159] Based on the above embodiments, the present application discloses another embodiment of an insulated water tank level control system for an energy storage coupled heat pump. In the steam generation system, the molten salt storage tank module utilizes the high specific heat capacity and high thermal stability of molten salt to convert thermal energy or electrical energy into thermal energy and store it. During the energy storage process, the molten salt absorbs heat to increase its temperature, thereby achieving efficient storage of energy. For example, during off-peak hours or when renewable energy is in surplus, molten salt can be heated and stored by an electric heat pump or a waste heat heat pump. The insulated water tank is used to store hot water generated by a heat pump or high-temperature water generated by a steam generator to ensure the continuity and stability of the steam generation process.

[0160] Reference Manual Attached Figure 6 , Figure 6The specific embodiment includes three molten salt storage tanks 50 connected in parallel, and the operating temperature is between 150° and 400°. In other embodiments, the molten salt storage tank 50 can also be replaced by heat storage modules such as solid heat storage, phase change heat storage, and thermochemical heat storage, and the various heat storage modules can be the same or different, and the operating temperatures can be the same or different. During the valley period, the molten salt storage tank 50 is electrically heated to 400°; when steam needs to be generated, the molten salt storage tank 50 releases heat, heats the high-temperature water to a second temperature of 150°, and transports it to the sub-cylinder 60. The steam output by the sub-cylinder 60 enters the desuperheater 70, and the desuperheated water from the insulated water tank 30 also enters the desuperheater 70, so that the desuperheater outputs steam at a third temperature of 130° for user use.

[0161] Assume that the predicted hot water flow F of the system at a certain moment is 1 ton / hour, and according to the temperature or waste heat conditions at that time, the time required for the heat pump to heat one ton of cold water to 95° is 3 hours, then the minimum hot water storage Emin is 1×3=3 tons. If multiple such heat pumps are set up, for example 3, the minimum hot water storage Emin is 1 ton. If there are both waste heat heat pumps and air source heat pumps, the heat pump heating capacity is calculated based on the waste heat conditions and temperature conditions. F is the predicted water consumption obtained based on monitoring and historical data, which is actually a dynamic curve, so Emin is also a dynamic curve. For example, at the end of the heating period, F tends to 0, and Emin also tends to zero.

[0162] This embodiment determines the minimum water storage capacity of the thermal insulation water tank according to the predicted value of the factory's heat demand and the heat pump heating capacity obtained according to the weather (temperature) or waste heat conditions, thereby ensuring the heating capacity and avoiding waste.

[0163] Based on the above embodiments, the present application discloses another embodiment of a liquid level control system for an insulated water tank coupled with an energy storage heat pump, wherein the heat pump comprises at least a first heat pump and a second heat pump. The first heat pump and / or the second heat pump are used to provide heat for the water in the insulated water tank.

[0164] The processor module is further configured to calculate the heat demand of the thermal insulation water tank at the first moment by combining the predicted water flow rate with the predicted ambient temperature. Based on the heating capacity of the heat pump, the preset priority and the heat demand of the thermal insulation water tank, the heating mode of the first heat pump and / or the second heat pump is controlled.

[0165] Specifically, in this embodiment, the first heat pump is a waste heat heat pump; the second heat pump is an air source heat pump.

[0166] Preferably, the processor module is specifically used to: calculate the heat demand of the thermal insulation water tank at the first moment in combination with the predicted water flow rate and the predicted ambient temperature. Calculate the heating capacity of the first heat pump and the second heat pump respectively. Determine whether the heating capacity of the first heat pump and / or the second heat pump can meet the heat demand. Control the heating mode of the first heat pump and / or the second heat pump in combination with the judgment result.

[0167] The present application provides another embodiment of an insulated water tank liquid level control system for an energy storage coupled heat pump. Based on any one of the embodiments of the above-mentioned system, the insulated water tank liquid level control system for an energy storage coupled heat pump further includes: a water replenishment module connected to the sensor module.

[0168] The sensor module includes a liquid level sensor for obtaining the current first water storage volume of the thermal insulation water tank and a temperature sensor for obtaining the current first temperature in the thermal insulation water tank.

[0169] The water replenishment module is further configured to automatically start the heat pump water replenishment function to replenish the thermal insulation water tank when the first water storage capacity is less than the minimum hot water storage capacity and the first temperature is not less than the water replenishment temperature set by the system, and automatically stop after detecting that the liquid level in the thermal insulation water tank reaches the upper limit of the liquid level set by the system.

[0170] The temperature sensor is also used to obtain the second temperature in the thermal insulation water tank after water replenishment.

[0171] The sensor module also includes a signal transceiver submodule, which is used to output a heating start signal to the heat pump when the second temperature is lower than the upper limit of the water temperature set by the system.

[0172] The heat pump is also used to automatically start cyclic heating after receiving the heating start signal and stop after the second temperature reaches the water temperature upper limit.

[0173] Specifically, when there is a peak demand that deviates from the predicted value, the insulated water tank can be supplemented with electric heating, or the molten salt storage tank can be supplemented with heating, or when a waste heat heat pump is used, the molten salt module can be used to heat the waste heat heat pump, thereby improving the heating capacity of the waste heat heat pump and shortening the heating time T. Specifically, the molten salt module includes a plurality of molten salt storage tanks, some of which release heat first, and the remaining molten salt storage tanks release heat in sequence. The molten salt storage tank that releases heat first can provide preheating for the molten salt storage tank that releases heat later, and can also provide heating function for the insulated water tank, and even provide preheating for the waste heat heat pump, so that the molten salt storage tank can achieve deep heat release.

[0174] Another benefit of staggered heat release from multiple molten salt storage tanks is that the heating capacity of the molten salt modules can be flexibly called upon. They can all be used for external heating of the system to obtain the maximum heating capacity, or they can be used in sequence for external heating to obtain a greater heat release depth. Some molten salt storage tanks can also be used for internal heating, such as providing emergency hot water for insulated water tanks, or providing waste heat for waste heat heat pumps.

[0175] During peak demand, since the actual flow rate F' exceeds the predicted value F, the minimum hot water volume according to Emin = F × T × (1 + r) will not be able to continuously meet the demand. At this time, supplementary heating can be used by electric heating or by using a molten salt storage tank that releases heat first to provide heat for the waste heat heat pump.

[0176] The present application provides another embodiment of an insulated water tank liquid level control system for an energy storage coupled heat pump. Based on any one of the embodiments of the above-mentioned system, the insulated water tank liquid level control system for an energy storage coupled heat pump further includes: a supplementary heating module.

[0177] The sensor module also includes a flow sensor for monitoring the real-time flow of the thermal insulation water tank.

[0178] The supplementary heating module supplements heating of the thermal insulation water tank when the real-time flow of the thermal insulation water tank at the first moment is greater than the predicted water flow.

[0179] The supplementary heating module specifically includes: an electric heating module and / or a molten salt storage tank heating module.

[0180] Specifically, if the real-time water flow rate continues to exceed the forecast, the water needs to be supplementally heated by a supplementary heating module including electric heating or molten salt storage tank heating.

[0181] In one implementation of this embodiment, while using a heat pump for heating, electric heating is used for supplementary heating. The heat pump uses an open heat pump, such as a transcritical carbon dioxide heat pump; during emergency heating, if the predicted short-term flow exceeds the prediction, the hot water output of the heat pump is directly connected in parallel with the output of the insulation water tank and provided to the molten salt module. This embodiment can use the flow directly output by the heat pump and superimpose it on the output of the insulation water tank to temporarily increase the heating capacity of the system.

[0182] In another embodiment of this embodiment, while using the heat pump for heating, the molten salt storage tank is used for supplementary heating. The molten salt storage tank adopts a deep heat release cycle and adopts a structure with an inner cylinder. Figure 7As shown. There can be one or more inner cylinders, and multiple inner cylinders can be concentrically arranged or independently distributed; the inner cylinder can be hollow (for radiation heat exchange) or filled with solid heat storage materials or molten salt; the inner cylinder is provided with a heat exchange coil, which can improve the heat release power of the molten salt module and facilitate the deep heat release of the molten salt. The heat exchange coil can still be retained on the outer cylinder. The structure and heat release cycle of the above-mentioned molten salt storage tank are conducive to the realization of emergency water replenishment heating in the above-mentioned embodiment.

[0183] In another implementation of this embodiment, when a waste heat heat pump is used, the waste heat heat pump is heated by a molten salt module, thereby improving the heating capacity of the waste heat heat pump. The heat pump is a waste heat heat pump, and the waste heat of the waste heat heat pump can be provided by a molten salt storage tank. After the supplementary heating, the waste heat of the waste heat heat pump increases, and the heating capacity increases accordingly, and the heating time for heating the same flow of water is shortened. In combination with the minimum water storage capacity calculated in this application, this embodiment utilizes the high energy efficiency of the heat pump, and improves the energy efficiency of the molten salt heat stored in the valley electricity through the heat pump, and has the flexibility to make full use of multiple molten salt storage tanks. In specific implementation, it is preferred to use a molten salt module and a waste heat heat pump to store hot water with a minimum water storage capacity, and then start the heating process.

[0184] The insulated water tank liquid level control method and system of an energy storage coupled heat pump of the present application have the same technical concept, and the technical details of the two embodiments are applicable to each other. In order to reduce repetition, they will not be repeated here.

[0185] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, only the division of the above-mentioned program modules is used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different program modules as needed, that is, the internal structure of the device can be divided into different program units or modules to complete all or part of the functions described above. The program modules in the embodiment can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into a processing unit, and the above-mentioned integrated unit can be implemented in the form of hardware or in the form of software program units. In addition, the specific names of the program modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application.

[0186] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

Claims

1. A method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump, characterized in that: The steps include: Heating water to a target temperature by a heat pump, and storing the water at the target temperature by a heat-insulating water tank; and monitoring relevant data of the heat pump and the heat-insulating water tank by a sensor; Combining the relevant data collected in real time with the historical relevant data, using regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future; Calculating the minimum amount of hot water to be stored in the thermal insulation water tank at the first moment according to the predicted water flow rate and the heating capacity of the heat pump; On the basis of the minimum hot water storage capacity, the liquid level of the thermal insulation water tank is controlled by a liquid level and temperature combined control method to meet the water demand of the user.

2. A method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 1, characterized in that: Also includes: The minimum amount of hot water to be stored in the thermal insulation water tank at the first moment is calculated by the following formula: Emin=F·T·(1+r); Where: F is the predicted water flow of the system at the first moment, unit: m 3 / h; T is the time required for the heat pump to heat the water with flow rate F from the initial temperature to the target temperature, unit: h; r is the safety redundancy ratio, which is 10% to 20%.

3. A method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump as claimed in claim 1 or 2, characterized in that: The heat pump comprises at least a first heat pump and a second heat pump; Also includes: Using the first heat pump and / or the second heat pump to provide heat to the water in the thermal insulation water tank; Based on the heating capacity of the heat pump, the preset priority and the heat demand of the thermal insulation water tank, the heating mode of the first heat pump and / or the second heat pump is controlled.

4. A method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump as claimed in claim 3, characterized in that: Also includes: Calculate the heat demand of the thermal insulation water tank at the first moment by combining the predicted water flow and the predicted ambient temperature; Specifically include: Obtain weather forecast information for a specified time period in the future, including but not limited to temperature, humidity, and wind speed; Use the pre-built thermal model, combined with the predicted ambient temperature conditions and the historical ambient temperature conditions, to predict the initial temperature of the water at the first moment; The predicted water flow rate and the initial temperature are combined to calculate the heat demand of the thermal insulation water tank at the first moment.

5. The method for controlling the liquid level of the heat preservation water tank of the energy storage coupled heat pump according to claim 4, characterized in that: Heat demand Q = F·ρ·c·Δt; Where: F is the water flow rate, unit: m 3 / h; ρ is the density of water, in kg / m 3 ; c is the specific heat capacity of water, in J / (kg·K); Δt is the temperature change, in °C; Δt = target temperature - initial temperature.

6. A method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump as claimed in claim 4 or 5, characterized in that: The controlling of the heating mode of the first heat pump and / or the second heat pump also includes: calculating heating capacities of the first heat pump and the second heat pump respectively; Determine whether the heating capacity of the first heat pump and / or the second heat pump can meet the heat demand.

7. The method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 5, characterized in that: The target temperature is lower than the saturation temperature by a first set temperature difference. The saturation temperature is affected by the pressure in the insulated water tank; when the heating temperature of the heat pump exceeds the boiling point of water, the pressure in the insulated water tank is adjusted to control the value of the saturation temperature; within a specified range, the higher the pressure, the higher the saturation temperature; The first set temperature difference is 2-10°C.

8. The method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 6, characterized in that: The first heat pump is a waste heat heat pump; the second heat pump is an air source heat pump.

9. The method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 1, characterized in that: Based on the minimum amount of hot water stored, the liquid level of the thermal insulation water tank is controlled by a combined liquid level and temperature control method; further comprising: Obtaining a current first water storage capacity of the thermal insulation water tank and a first temperature in the thermal insulation water tank; When the first water storage capacity is less than the minimum hot water storage capacity, and the first temperature is not less than the water replenishment temperature set by the system, the heat pump water replenishment function is automatically started to replenish the thermal insulation water tank; and the operation is automatically stopped after the liquid level in the thermal insulation water tank reaches the upper limit of the liquid level set by the system; The second temperature in the insulated water tank after water replenishment is obtained. When the second temperature is lower than the upper limit of the water temperature set by the system, a heating start signal is output to the heat pump so that the heat pump automatically starts to perform cyclic heating until the second temperature reaches the upper limit of the water temperature and stops.

10. The method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 1, characterized in that: Also includes: The real-time flow rate of the thermal insulation water tank is monitored by a flow sensor; when the real-time flow rate of the thermal insulation water tank is greater than the predicted water flow rate at the first moment, the thermal insulation water tank is supplementarily heated; Specifically including: supplementary heating by electric heating method; Or, supplementary heating is performed by heating the molten salt tank by first releasing heat; Alternatively, supplementary heating can be provided by first releasing heat from a molten salt storage tank to supply heat to a heat pump.

11. The method for controlling the liquid level of an insulated water tank of an energy storage coupled heat pump according to claim 10, characterized in that: The maximum heating temperature of the first heat pump is the value of the lowest working temperature of the molten salt storage tank for generating steam minus the second set temperature difference, and the second set temperature difference is 10-50°C.

12. A thermal insulation water tank level control system for an energy storage coupled heat pump, characterized in that: Including heat pump, thermal water tank, sensor module, processor module; The heat pump is connected to the thermal insulation water tank and is used to provide heat for the water in the thermal insulation water tank; The sensor module is used to monitor the relevant data of the heat pump and the insulated water tank; the relevant data specifically includes: temperature sensing data of the heat pump and the insulated water tank; flow sensing data and liquid level sensing data of the insulated water tank; The processor module is used to combine the relevant data collected in real time and the historical relevant data, use regression analysis algorithm and time series analysis algorithm to perform data analysis and predict the predicted water flow at the first moment in the future; The processor module is also used to calculate the minimum amount of hot water to be stored in the insulated water tank at the first moment based on the predicted water flow and the heating capacity of the heat pump; based on the minimum amount of hot water, control the liquid level of the insulated water tank by a combined level and temperature control method to meet the user's water demand.

13. The insulated water tank liquid level control system of the energy storage coupled heat pump according to claim 12, characterized in that: The heat pump comprises at least a first heat pump and a second heat pump; the first heat pump and / or the second heat pump are used to provide heat for the water in the thermal insulation water tank; The processor module is further used to calculate the heat demand of the thermal insulation water tank at the first moment by combining the predicted water flow rate and the predicted ambient temperature; The processor module is also used to control the heating mode of the first heat pump and / or the second heat pump based on the heating capacity of the heat pump, the preset priority and the heat demand of the insulated water tank.

14. The insulated water tank liquid level control system of the energy storage coupled heat pump according to claim 12, characterized in that: Also includes: A water replenishment module connected to the sensor module; The sensor module includes a liquid level sensor for obtaining the current first water storage volume of the thermal insulation water tank; and a temperature sensor for obtaining the current first temperature in the thermal insulation water tank; The water replenishment module is further used to automatically start the heat pump water replenishment function to replenish the thermal insulation water tank when the first water storage capacity is less than the minimum hot water storage capacity and the first temperature is not less than the water replenishment temperature set by the system; and automatically stop after detecting that the liquid level in the thermal insulation water tank reaches the liquid level upper limit set by the system; The temperature sensor is also used to obtain the second temperature in the thermal insulation water tank after water replenishment; The sensor module further includes a signal transceiver submodule, which is used to output a heating start signal to the heat pump when the second temperature is lower than the upper limit of the water temperature set by the system; The heat pump is also used to automatically start cyclic heating after receiving the heating start signal and stop after the second temperature reaches the water temperature upper limit.

15. The insulated water tank liquid level control system of the energy storage coupled heat pump according to claim 12, characterized in that: Also includes: Supplementary heating module; The sensor module also includes a flow sensor for monitoring the real-time flow of the thermal insulation water tank; The supplementary heating module supplements heating of the thermal insulation water tank when the real-time flow of the thermal insulation water tank at the first moment is greater than the predicted water flow; The supplementary heating module specifically includes: an electric heating module and / or a molten salt storage tank heating module.

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