Waste heat-demand two-stage optimization design method for multi-energy combined supply Carnot battery system

Abstract

The invention discloses a waste heat-demand two-stage optimization design method for a multi-energy combined supply Carnot battery system, and belongs to the field of energy storage and comprehensive energy utilization, and the method comprises the steps: determining the energy demand and waste heat source condition of a target energy supply object; constructing a multi-energy combined supply Carnot battery energy storage system model composed of a multi-energy conversion subsystem and a Carnot battery subsystem; the method comprises the following steps: performing parameter optimization on performance expressions of an energy storage loop and an energy release loop of a Carnot battery subsystem through first-layer optimization, and determining Carnot battery system performance and state parameters of each point under unit cold and heat source flow; and through second-layer optimization, multi-objective optimization is carried out on the efficiency of the first law of thermodynamics, the efficiency of the second law of thermodynamics and the economical efficiency of the system, and the optimal heat source flow input into the energy storage loop, the optimal heat storage water flow input into the multi-energy conversion subsystem, the optimal heat storage water flow input into the energy release loop and the corresponding overall performance of the Carnot battery system are determined.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage and integrated energy utilization, and more specifically, relates to a waste heat-demand dual-stage optimization design method for a multi-energy co-generation Carnot battery system. Background Art

[0002] Kanot battery energy storage technology is a large-scale physical energy storage system that uses thermal energy as a storage medium. Compared to other large-scale energy storage technologies, Kanot battery technology offers high energy storage density, low cost, high efficiency, and strong flexibility, unconstrained by geographical conditions. Furthermore, the Kanot battery system has excellent waste heat coupling, which improves its performance. Therefore, the Kanot battery system is particularly suitable for industrial scenarios with waste heat. However, industrial scenarios require multiple energy sources, including cooling, heat, and electricity. Traditional Kanot battery technology only converts "electricity-heat-electricity," providing a relatively limited energy supply and failing to meet the diverse energy needs of industrial scenarios. By combining a traditional Kanot battery system with a multi-energy conversion module, a multi-energy cogeneration Kanot battery energy storage system is created. Using stored thermal energy as a heat source, it provides energy to the multi-energy conversion subsystems, completing energy supply or conversion, achieving the cogeneration of cooling, heat, and electricity. In industrial production, high economic efficiency means high profits. In the system design process, performance and scale are factors that affect economic efficiency, and the system's performance and scale should be optimized. In the existing design of Carnot battery energy storage systems coupled with waste heat, most of them do not take into account the matching relationship between waste heat scale and energy demand. For example, if all the waste heat energy is used, the temperature of the waste heat flowing out of the system is relatively low, which restricts the system performance. At the same time, it may cause the scale to be too large, which reduces economic efficiency. If the target system is operating at optimal performance, the energy demand can be met by inputting part of the waste heat source, and the remaining waste heat can be supplied to other systems without causing energy waste. At the same time, the system scale and cost can be reduced, improving economic efficiency. How to balance the performance and cost of the system so that the system scale meets the energy supply target while achieving optimal performance is an urgent problem to be solved in the design of multi-energy combined supply Carnot battery energy storage systems. Summary of the Invention

[0003] The present invention provides a waste heat-demand dual-stage optimization design method for a multi-energy co-generation Carnot battery system. This method enables the multi-energy co-generation Carnot battery energy storage system to simultaneously achieve optimal magnitude and optimal performance, avoiding magnitude redundancy or deficiency while maximizing system performance and economy.

[0004] The technical solution of the present invention is as follows:

[0005] On the one hand, an embodiment of the present invention provides a waste heat-demand two-level optimization design method for a multi-energy co-supply Carnot battery system, including: determining the specific cold energy, heat energy and electric energy requirements of the target energy supply object, quantifying the above energy requirements into temperature, pressure, flow and power parameters respectively, and determining the waste heat level and quality of the target energy supply object; constructing a Carnot battery subsystem model, and multiple models can be constructed according to different configurations; establishing a corresponding multi-energy conversion subsystem model according to the energy demand of the target energy supply object; setting the boundary condition parameters of the Carnot battery subsystem based on the energy demand of the target energy supply object, and combining the multi-energy conversion subsystem to form a multi-energy co-supply Carnot battery. Energy storage system simulation model; through the first-level optimization, the parameters of the energy storage circuit and energy release circuit of the Carnot battery subsystem are optimized to determine the performance of the Carnot battery subsystem under unit cold and heat source flow; through the second-level optimization, the first law of thermodynamics efficiency, second law of thermodynamics efficiency and economy of the multi-energy combined supply Carnot battery energy storage system are multi-objective optimized to determine the optimal heat source flow input to the heat pump system, the hot water storage flow input to the multi-energy conversion subsystem and the hot water storage flow input to the energy release circuit, as well as the corresponding overall performance of the multi-energy combined supply Carnot battery energy storage system; based on the above optimization calculation results, the target multi-energy combined supply Carnot battery energy storage system design parameters are determined.

[0006] According to one embodiment of the present invention, a Carnot battery subsystem of a multi-energy cogeneration Carnot battery energy storage system includes: a heat storage device, at least one energy storage circuit, and at least one energy release circuit, each circuit including at least two pressure regulating devices and two heat exchange devices;

[0007] The heat storage device includes a high-temperature heat storage tank and a low-temperature heat storage tank; the pressure regulating devices in the energy storage circuit and the energy release circuit include: two of a pump, a compressor, an expander, and a throttle valve; the heat exchange devices in the energy storage circuit and the energy release circuit include but are not limited to: an evaporator, a condenser, a preheater, a regenerator, etc.;

[0008] According to one embodiment of the present invention, the first-level optimization is divided into two parts: energy storage circuit optimization and energy release circuit optimization. The variables for energy storage circuit optimization are: evaporation pressure, condensation pressure, evaporator working fluid outlet superheat, condenser working fluid outlet temperature; the variables for energy release circuit optimization are: evaporation pressure, condensation pressure, evaporator working fluid outlet superheat, condenser working fluid outlet temperature and the ratio of waste heat to working fluid flow rate; the goal of energy storage circuit optimization is the ratio of heat released by the condenser to the electrical energy input into the energy storage circuit; the optimization goal of the energy release circuit is the ratio of the net output electrical energy of the energy release circuit to the heat energy absorbed in the evaporator.

[0009] Through the first-level optimization, the state parameters of each point of the Carnot battery system under unit flow when the performance is optimal, the flow ratio of the heat source to the working fluid, and the flow ratio of the cold source to the working fluid can be obtained, and the results can be stored.

[0010] The second level of optimization involves overall system optimization. Specifically, the results of the first level optimization are input and then subjected to magnitude optimization. The optimization variables are: the heat source flow rate of the energy storage circuit, the hot water storage flow rate of the multi-energy module, and the hot water storage flow rate of the energy release circuit. The optimization objectives are: the first law of thermodynamics efficiency, the second law of thermodynamics efficiency, and the levelized cost of energy for the multi-energy Carnot battery energy storage system.

[0011] Through the second-level optimization, we can obtain the heat source flow input to the energy storage loop, the hot water storage flow input to the multi-energy conversion subsystem, and the hot water storage flow input to the energy release loop when the first law of thermodynamics efficiency, the second law of thermodynamics efficiency, and the levelized energy cost of the multi-energy combined supply Carnot battery energy storage system are all optimized.

[0012] Based on the specific flow rates obtained from the second-level optimization and the flow ratios obtained from the first-level optimization, all the flow parameters required for system design are obtained. Based on the flow parameters and the state parameters obtained from the first-level optimization, the system magnitude can be calculated. The system magnitude includes: the heat exchange capacity of the heat exchangers in the Carnot battery subsystem, the electrical energy input to the pressure regulating device, the electrical energy output from the pressure regulating device, the required cold and heat source magnitudes for the system, the heat input to the multi-energy conversion subsystem, and the magnitudes of the corresponding energy conversion equipment. Based on these optimization calculation results, the design parameters of the target multi-energy cogeneration Carnot battery energy storage system are determined.

[0013] Another aspect of the present invention provides a multi-energy combined supply Kanot battery energy storage system based on the above-mentioned multi-energy combined supply Kanot battery energy storage system optimization design method, comprising: a Kanot battery subsystem including: a heat storage device; an energy storage circuit including: a plurality of heat exchangers, at least one of which performs heat exchange with an external heat source to absorb heat, and at least one heat exchanger performs heat exchange with the above-mentioned energy storage device to release heat to the energy storage device; at least one compression regulating device that converts input electrical energy into thermal energy; wherein the above-mentioned energy storage circuit converts electrical energy into thermal energy and transmits the thermal energy to the above-mentioned thermal storage device; an energy release circuit. It comprises: a plurality of heat exchangers, at least one of which performs heat exchange with an external cold source to release heat, and at least one heat exchanger performs heat exchange with the above-mentioned energy storage device to absorb heat from the energy storage device; at least one compression regulating device that outputs electrical energy; wherein the above-mentioned energy release circuit converts thermal energy into electrical energy output and provides it to a target energy supply object. The multi-energy conversion subsystem includes an energy supply device and an energy conversion device; wherein the energy supply device is used to directly supply the heat stored in the heat storage device in the Carnot battery system to the target energy supply object, and the energy conversion device is used to convert the heat stored in the heat storage device in the Carnot battery system into other forms of energy and provide it to the energy supply object.

[0014] According to the present invention, the optimization design method for a multi-energy co-supply Kanot battery energy storage system constructs simulation models for the Kanot battery subsystem and the multi-energy conversion subsystem based on the multi-energy requirements of the target energy supply object. A first-level optimization optimizes system performance while simultaneously obtaining state parameters and flow ratios at each point per unit flow rate. A second-level optimization optimizes system economics while obtaining specific flow rates. Combined with the first-level optimization results, the design parameters for the multi-energy co-supply Kanot battery are calculated to achieve optimal performance and economics.

[0015] Beneficial effects:

[0016] 1. Accurately match waste heat levels with demand: Through dual-layer optimization, waste heat input and energy demand are balanced to avoid system redundancy or insufficiency and improve energy utilization.

[0017] 2. Multi-objective collaborative optimization: Combining thermodynamic efficiency and economic indicators to ensure that the system operates efficiently while achieving the lowest cost.

[0018] 3. Flexible energy supply capability: Integrates refrigeration, carbon capture, and heating modules to meet the needs of combined cooling, heat, and electricity in industrial scenarios.

[0019] 4. Optimal solution for performance and magnitude: Through a hierarchical optimization strategy, subsystem performance and overall system magnitude are optimized separately to achieve a globally optimal design. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Flowchart of the waste heat-demand dual-stage optimization design method for a multi-energy cogeneration Carnot battery system according to the present invention.

[0021] Figure 2 It is a detailed first-level optimization flow chart of the present invention.

[0022] Figure 3 It is a detailed second-level optimization flow chart of the present invention.

[0023] Figure 4 This is a schematic multi-energy co-supply Carnot battery energy storage system provided by the present invention.

[0024] The meanings of the reference numerals are as follows:

[0025] 1-First three-way valve

[0026] 2-First evaporator

[0027] 3-Compressor unit

[0028] 4-First condenser

[0029] 5-First regenerator

[0030] 6-Throttle valve

[0031] 7-High temperature heat storage tank

[0032] 8-Low temperature heat storage tank

[0033] 9-Low-temperature hot water storage pump

[0034] 10-Second three-way valve

[0035] 11-High temperature hot water storage pump

[0036] 12-Third three-way valve

[0037] 13-Second evaporator

[0038] 14-Expansion generator set

[0039] 15-Second regenerator

[0040] 16-Preheater

[0041] 17-Second condenser

[0042] 18-Working fluid pump

[0043] 19-Target energy supply object DETAILED DESCRIPTION

[0044] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. However, the following embodiments are intended only to explain the present invention, and the scope of protection of the present invention should include the entire contents of the claims. Moreover, through the description of the following embodiments, those skilled in the art can fully implement the entire contents of the claims of the present invention.

[0045] Example

[0046] like Figure 1 As shown, the waste heat-demand two-stage optimization design method of the multi-energy combined supply Carnot battery system includes steps 1-5.

[0047] In step 1, the energy requirements of the target energy supply object are determined. This includes cooling energy requirements, heating energy requirements, and electrical energy requirements. According to an embodiment of the present invention, the energy requirements include the temperature, pressure, and flow requirements of the required heating and cooling energy, and the power or amount of electrical energy required.

[0048] In step 2, a simulation model of the Carnot battery system and the multi-energy conversion module is established.

[0049] According to an embodiment of the present invention, the Carnot battery subsystem includes at least one energy storage circuit, an energy release circuit, and a heat storage device. The energy storage circuit is based on a heat pump cycle, converting electrical energy into thermal energy; the energy release circuit can be a power cycle selected as needed to achieve the conversion of thermal energy into electrical energy. The heat storage device can be selected from one or more of sensible heat storage, latent heat storage, and thermochemical heat storage, as needed.

[0050] In step 3, the boundary conditions of the energy supply object are input to perform the first level optimization.

[0051] According to an embodiment of the present invention, the goal of the first-level optimization is the performance of the energy storage circuit and the energy release circuit.

[0052] According to an embodiment of the present invention, the performance of the energy storage circuit is expressed as COP, which specifically means the ratio of heat provided to power consumed. Its mathematical expression is:

[0053] (1)

[0054] in, is the heat storage power of the energy storage circuit, kW; Input electrical power to the energy storage circuit, kW.

[0055] According to an embodiment of the present invention, the performance of the energy release circuit is as follows: , specifically the ratio of output power to consumed thermal storage heat, and its mathematical expression is:

[0056] (2)

[0057] in, is the absorption and heat storage power of the energy release circuit, kW; The output power of the energy release circuit, kW.

[0058] According to an embodiment of the present invention, the calculation of the optimization target involves the calculation of heat and electrical power. For heat power, the power at a certain moment when the multi-energy cogeneration Carnot battery energy storage system is operating is:

[0059] (3)

[0060] For electric power, the power at a certain moment when the multi-energy combined supply Carnot battery energy storage system is working is:

[0061] (4)

[0062] in, The temperature of the waste heat input to the multi-energy combined supply Carnot battery energy storage system, K; is the temperature of waste heat flowing out of the multi-energy combined supply Carnot battery energy storage system, K; is the high temperature heat storage temperature, K; is the low temperature heat storage temperature, K; is the evaporation pressure in the energy storage or release circuit, kPa; is the condensation pressure in the energy storage or release circuit, kPa; is the flow ratio of waste heat to working fluid in the energy storage or release circuit; It is the flow ratio of stored hot water to working fluid in the energy storage or release circuit.

[0063] According to an embodiment of the present invention, Figure 1 、 Figure 2 As shown, the energy storage loop is optimized with COP as the objective, using the evaporator outlet superheat, condenser outlet temperature, evaporation pressure, and condensation pressure as optimization variables. The optimization variable range is set as required and entered into the optimization program. The evaporator outlet enthalpy is calculated based on the evaporation pressure and the evaporator outlet superheat. The condenser outlet enthalpy is calculated based on the condenser outlet temperature and condensation pressure. The compressor inlet and throttle valve inlet state parameters are calculated using the heat balance and pinch point temperature difference method. First, assuming the compressor outlet entropy is equal to the inlet entropy, the compressor outlet enthalpy is calculated based on this assumed compressor outlet entropy and the condensing pressure. The actual compressor outlet enthalpy is then calculated based on the compressor isentropic efficiency, and the actual compressor outlet state parameters are then calculated. Assuming the throttle valve outlet enthalpy is equal to the inlet enthalpy, the throttle valve outlet state parameters are calculated based on the throttle valve outlet enthalpy and evaporation pressure. This method generates the state parameters at each point in the energy storage cycle, and the COP of the energy storage loop is calculated based on these state parameters. Save the status parameters and flow ratio of each point.

[0064] Optimization of the energy release circuit As the optimization objective, using the organic Rankine cycle as an example, the evaporator outlet superheat, evaporation pressure, condenser outlet temperature, and condensing pressure to flow ratio are used as optimization variables. The optimization variable range is set according to requirements and entered into the optimization program. The evaporator outlet enthalpy is calculated based on the evaporation pressure and the evaporator outlet superheat. First, assuming the expander outlet entropy is equal to the inlet entropy, the expander outlet enthalpy is calculated based on this assumed expander outlet entropy and the condensing pressure. The actual compressor outlet enthalpy is calculated based on the expander isentropic efficiency, and the actual expander outlet state parameters are then calculated. The condenser outlet state parameters are calculated based on the condenser outlet temperature and condensing pressure. First, assuming the working pump outlet entropy is equal to the inlet entropy, the working pump outlet enthalpy is calculated based on this assumed working pump outlet entropy and the evaporation pressure. The actual working pump outlet enthalpy is calculated based on the working pump isentropic efficiency, and the actual working pump outlet state parameters are then calculated. Based on the heat balance, the regenerator cold and hot side outlet state parameters are calculated. Save the status parameters and flow ratio of each point.

[0065] In step 4, the energy demand of the energy supply object is input and the second level optimization is performed.

[0066] According to an embodiment of the present invention, the second-level optimization objectives are: efficiency according to the first law of thermodynamics, efficiency according to the second law of thermodynamics, and economic indicators.

[0067] According to an embodiment of the present invention, the efficiency according to the first law of thermodynamics is the ratio of the total energy output by the multi-energy co-generation Carnot battery energy storage system to the total electrical energy input into the multi-energy co-generation Carnot battery energy storage system. Its mathematical expression is:

[0068] (5)

[0069] in, is the output electrical energy of the energy release circuit, kW; is the energy output by the multi-energy conversion subsystem, kW; is the electrical energy input into the energy storage circuit, kW.

[0070] According to an embodiment of the present invention, the efficiency of the second law of thermodynamics is the ratio of the system output exergy to the input exergy, which represents the degree of preservation of available work during the energy conversion process. Its mathematical expression is:

[0071] (6)

[0072] in, is the output exergy of the multi-energy conversion subsystem, kW; is the exergy of waste heat input into the energy storage circuit, kW; is the exergy of waste heat input into the energy release circuit, kW.

[0073] According to an embodiment of the present invention, the economic indicator is the levelized cost of energy, which is expressed as follows:

[0074] (7)

[0075] (8)

[0076] in, The total equipment purchase cost of the multi-energy cogeneration Kano battery energy storage system is RMB; The service life of the multi-energy cogeneration Kano battery energy storage system is years; is the discount rate; The annual cost of the multi-energy cogeneration Kano battery energy storage system, ￥; The total annual output of electricity and other energy from the multi-energy Kano battery energy storage system, in kWh; The annual operation and maintenance cost of the multi-energy cogeneration Kano battery energy storage system, ￥; The electricity price when the energy storage circuit of the multi-energy cogeneration Carnot battery energy storage system is working, ￥; The annual power input for the Kano battery energy storage system for the multi-energy cogeneration system, kWh; For the residual value.

[0077] According to an embodiment of the present invention, Figure 1 and Figure 3 As shown, the second-level optimization objective is to determine the magnitude of the multi-energy cogeneration system. After the first-level optimization, the state parameters at each point in the system are already determined, and the magnitude is determined by the flow rate. The input optimization variables are: the heat source flow rate of the energy storage circuit, the hot water storage flow rate of the multi-energy cogeneration module, and the hot water storage flow rate of the energy release circuit. Based on the heat source flow rate of the energy storage circuit and the flow rate ratio of the state parameters and each point obtained from the first-level optimization, the magnitude of the energy storage circuit, the total amount of hot water storage, and the total electrical energy input are calculated. Based on the total amount of hot water storage, the hot water storage flow rate is distributed between the multi-energy module and the energy release circuit. Based on the specific flow distribution, the magnitude of the multi-energy module, the magnitude of the energy release circuit, the energy output, and the total electrical energy output are calculated. Based on these results, the first law of thermodynamics efficiency, the second law of thermodynamics efficiency, and the levelized cost of energy of the multi-energy cogeneration Carnot battery energy storage system are calculated. Using a multi-objective optimization algorithm, these three optimization objectives are optimized to obtain the optimal values ​​and the specific values ​​of the heat source flow rate of the energy storage circuit, the hot water storage flow rate of the multi-energy conversion subsystem, and the hot water storage flow rate of the energy release circuit at the optimal values. These parameters are then saved.

[0078] In step 5, based on the above optimization results, the optimal system parameters are calculated.

[0079] like Figure 4 As shown, this embodiment provides a schematic multi-energy co-generation Carnot battery energy storage system. Specifically, it includes the following components and operation process:

[0080] 1. Energy storage stage (electrical energy → thermal energy storage)

[0081] Waste heat source input: The external waste heat source is divided into two paths through the first three-way valve 1: one path enters the first evaporator 2 to exchange heat with the working fluid of the energy storage circuit, and the other path is directly supplied to other systems.

[0082] Energy storage circuit operation:

[0083] After absorbing the waste heat in the first evaporator 2, the working fluid enters the first regenerator 5 to absorb the heat of the working fluid at the outlet of the first condenser 4, and then enters the compressor unit 3 to increase the pressure and temperature;

[0084] The high-temperature and high-pressure working fluid enters the first condenser 4, releases heat to the high-temperature heat storage tank 7, and is then pre-cooled by the first regenerator 5;

[0085] After the working medium is depressurized by the throttle valve 6, it returns to the first evaporator 2 to complete the cycle;

[0086] The low-temperature hot water pump 9 drives the low-temperature hot water to flow from the low-temperature heat storage tank 8 into the first condenser 4 to absorb heat, and then is stored in the high-temperature heat storage tank 7 after being heated.

[0087] 2. Energy release stage (heat energy → electrical energy output)

[0088] Hot water distribution: The high-temperature hot water pump 11 delivers the high-temperature hot water to the third three-way valve 12, which is divided into two routes:

[0089] All the way into the second evaporator 13, providing heat source for the energy release circuit;

[0090] The other path passes through the multi-energy conversion subsystem, releases heat energy, and then returns to the high-temperature heat storage tank 7.

[0091] Energy release circuit operation:

[0092] After absorbing heat in the second evaporator 13, the working fluid enters the expansion generator set 14 to generate electricity;

[0093] After the exhaust steam is cooled by the second regenerator 15 and the second condenser 17, it is pressurized by the working fluid pump 18 and sent back to the preheater 16 for preheating, completing the cycle.

[0094] The cold source of the second condenser 17 is provided by external cooling water or ambient air.

[0095] 3. Combined energy generation (heat energy → cooling / heat / electricity)

[0096] Hot water storage distribution: The second three-way valve 10 and the third three-way valve 12 distribute part of the high-temperature hot water storage to the target energy supply object 19, including but not limited to:

[0097] Direct heating: providing high-temperature steam to industrial equipment through heat exchangers;

[0098] Combined cooling and supply: drives absorption chillers to generate cooling energy;

[0099] Carbon capture and cogeneration: desorbing carbon dioxide through a flash tank and a carbon capture device.

[0100] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A dual-stage optimization design method for waste heat and demand in a multi-energy cogeneration Carnot battery system, characterized in that: The following steps are involved: Step 1: Determine the cooling, heating, and electrical energy requirements of the target energy supply object, quantify them into temperature, pressure, flow, and power parameters, and obtain waste heat level and quality data; Step 2: Construct a Carnot battery subsystem model and a multi-energy conversion subsystem model. The Carnot battery subsystem includes a heat storage device, an energy storage circuit, and an energy release circuit. The multi-energy conversion subsystem includes an energy conversion device and an energy supply object. Step 3: Based on the waste heat conditions and energy requirements, set the system boundary conditions and perform the first-level optimization. Taking the energy storage circuit performance coefficient and energy release circuit efficiency as the optimization targets, optimize the evaporation pressure, condensing pressure, working fluid superheat, and flow ratio to obtain the system state parameters under unit flow. Step 4: Perform the second-level optimization, taking the efficiency of the first law of thermodynamics, the efficiency of the second law of thermodynamics, and the levelized cost of energy as multiple objectives, to optimize the heat source flow rate input to the energy storage loop, the hot water storage flow rate input to the multi-energy conversion subsystem, and the hot water storage flow rate input to the energy release loop; Step 5: Determine the system design parameters based on the optimization results, including the heat transfer capacity of the heat exchanger, the power of the pressure regulating device, the magnitude of the cold and heat sources, the magnitude of the multi-energy conversion subsystem, and the magnitude of the heat storage device.

2. The method according to claim 1, characterized in that The Carnot battery subsystem includes: Energy storage circuit: comprising a first evaporator (2), a compressor unit (3), a first condenser (4), a first regenerator (5) and a throttle valve (6), for converting electrical energy into thermal energy and storing the energy; Energy release circuit: comprising a preheater (16), a second evaporator (13), an expansion generator set (14), a second regenerator (15) and a working fluid pump (18), for converting thermal energy into electrical energy output; The heat storage device comprises a high-temperature heat storage tank (7) and a low-temperature heat storage tank (8), and the energy storage medium is driven to circulate through a pump group.

3. The method according to claim 1, characterized in that The multifunctional conversion subsystem includes but is not limited to the following functional modules: Refrigeration module: converts stored heat into cold energy through absorption refrigeration unit; Carbon capture module: uses heat storage to desorb carbon dioxide through a flash tank and carbon capture device; Heating module: Directly supplies heat energy through a heat exchanger.

4. The method according to claim 1, wherein In the first-level optimization, the goal of the energy storage loop optimization is the ratio of heat released by the condenser to the electrical energy input to the energy storage loop, and the optimization variables include evaporation pressure, condensing pressure, evaporator working fluid outlet superheat, and condenser working fluid outlet temperature; the goal of the energy release loop optimization is the ratio of net output electrical energy to the thermal energy absorbed by the stored water, and the optimization variables include evaporation pressure, condensing pressure, evaporator working fluid outlet superheat, condenser working fluid outlet temperature, and the ratio of waste heat to working fluid flow.

5. The method according to claim 1, wherein The three goals of the second-level optimization are: First Law of Thermodynamics Efficiency: The ratio of a system's total output energy to its input electrical energy; The Second Law of Thermodynamics Efficiency: The ratio of a system's output exergy to its input exergy; Levelized cost of energy: A comprehensive economic indicator based on equipment purchase cost, operation and maintenance expenses, and energy output.

6. The method according to claim 1, wherein The calculation of the efficiency of the second law of thermodynamics includes: Input exergy is the available energy of waste heat source and electricity; Output exergy is the usable energy of electricity, cooling and heat.

7. The method according to claim 1, characterized in that The system design parameters include: The heat exchanger heat transfer capacity, compressor power and hot water storage flow rate of the energy storage circuit; The expander power generation power, working fluid pump power, heat exchanger heat transfer and cold source flow rate of the energy release circuit; Capacity of heat storage device and magnitude of heat storage pump The input heat of the multi-energy conversion subsystem and the corresponding energy conversion equipment level.

8. A multi-energy co-supply Carnot battery energy storage system designed based on the method according to any one of claims 1 to 7, characterized in that: include: Carnot battery subsystem: includes energy storage circuit, energy release circuit and heat storage device. The energy storage circuit converts electrical energy into thermal energy storage through heat pump cycle, and the energy release circuit converts thermal energy into electrical energy through power cycle. Multi-energy conversion subsystem: The hot water storage flow is distributed through a three-way valve to drive modules including but not limited to the refrigeration module, carbon capture module and heating module.

9. The system according to claim 8, characterized in that The working medium of the energy storage circuit and the energy release circuit is an organic working medium, water or carbon dioxide, and the working medium of the multi-energy conversion subsystem is water.

10. The system according to claim 8, wherein: The heat storage device realizes the storage and release of thermal energy through a high-temperature hot water storage pump and a low-temperature hot water storage pump, and the energy release circuit improves the circulation efficiency by inputting the waste heat source into the preheater.

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