Multi-energy cooperative operation method for photovoltaic-photo-thermal-electric heater

Abstract

The invention discloses a multi-energy cooperative operation method for a photovoltaic-photo-thermal-electric heater. The method comprises the specific steps that a cooperative operation framework of a photovoltaic-photo-thermal-electric heater multi-energy system is constructed; establishing a photovoltaic power model and a power abandoning constraint, a photo-thermal power generation model and a power constraint, and an electric heater operation model and a power constraint; designing a start-stop control model and equipment switching constraints of the photo-thermal power generation system; constructing an auxiliary service model and power constraint for measuring the auxiliary service participation capability of the photo-thermal power generation system; the method comprises the following steps of: constructing a collaborative optimization scheduling model by taking the annual total revenue maximization of a photovoltaic-photo-thermal-electric heater multi-energy system as a target, and setting a plurality of constraint conditions; and solving the collaborative optimization scheduling model to obtain a multi-energy collaborative optimal scheduling scheme throughout the year. According to the method, the economical efficiency, flexibility and controllability of the multi-energy system are remarkably improved, the technical bottlenecks that an existing model is single in target, insufficient in physical coupling and the like are effectively broken through, and the method has wide engineering application prospects and industrial popularization value.

Description

Technical Field

[0001] This invention relates to the field of energy collaborative optimization scheduling technology, and in particular to a multi-energy collaborative operation method for photovoltaic-photothermal-electric heaters. Background Technology

[0002] In recent years, with the deepening of my country's "dual carbon" goals, the scale of new energy base construction has continued to expand, and the installed capacity of renewable energy power generation such as photovoltaic and solar thermal power has grown rapidly, accelerating the transformation of the energy structure towards low-carbon and renewable energy. Photovoltaic power generation and solar thermal power generation have outstanding advantages of being clean and sustainable in large-scale base scenarios, but both have significant volatility and intermittency characteristics, posing challenges to the safe and stable operation of the power system and the high-proportion consumption of new energy.

[0003] To enhance the absorption capacity of new energy in large-scale energy bases, alleviate the problem of power curtailment, and improve the flexibility of system regulation, flexible regulation equipment such as solar thermal energy storage and electric heaters are widely integrated into the multi-energy systems of new energy bases. This enables multi-path energy flow and flexible allocation, and promotes the formation of a new energy system architecture that is complementary to multiple energy sources, such as photovoltaics, solar thermal energy, and electric heaters.

[0004] Currently, academic and engineering communities have conducted research on various models and scheduling methods to optimize the operation of multi-energy systems in large-scale new energy bases. These studies primarily focus on power generation planning and energy management for single energy types (such as photovoltaics and wind power) or single devices (such as solar thermal energy storage). However, research on the coordinated optimization of systems with multiple types of equipment, such as photovoltaics, solar thermal, and electric heaters, remains relatively weak. Especially under complex operating conditions involving multi-energy coupling, multiple temporal and spatial scales, and market ancillary services, the following major shortcomings exist: (1) The multi-energy coupling mechanism is not fully expressed: the existing models focus on single-energy systems and lack systematic modeling of energy flow and complementary regulation of multiple devices such as photovoltaic, photothermal and electric heaters, which makes it difficult to fully reflect the multi-energy complementarity and flexible regulation capabilities; (2) Insufficient utilization of flexible resources and ancillary service capabilities: The existing dispatching strategy has not fully developed the adjustment potential of flexible resources such as thermal storage and electric heaters. Ancillary service capabilities (such as peak shaving, frequency regulation, and reserve) have not been optimized in coordination with the new energy power generation plan, resulting in serious curtailment of new energy power and insufficient overall system operation flexibility. (3) Single objective and insufficient collaborative optimization capability: The optimization objectives of traditional multi-energy systems are mainly based on economic efficiency or single absorption rate, and fail to take into account multiple objectives such as new energy absorption, system flexibility, and ancillary service revenue. The space for synergistic improvement of system carbon reduction and economic benefits is limited. (4) Insufficient optimization of high spatiotemporal resolution and multiple time periods: Most studies only focus on a single time scale of day / hour, and fail to take into account the annual full-time operation optimization of 8760 hours, which makes it difficult to support the annual full-scenario optimal operation decision of the multi-energy system of the new energy base. In summary, there is currently a lack of a comprehensive multi-energy synergistic operation method and optimization system that can systematically reflect the multi-energy coupling mechanism of photovoltaic-photothermal-electric heaters, take into account multiple objectives for optimization, achieve flexible regulation and ancillary service participation, and support the all-time operation of high-proportion renewable energy in large-scale renewable energy bases. This lack of a system hinders the improvement of the economy, flexibility, and high-proportion renewable energy consumption level of multi-energy systems in large-scale renewable energy bases. Therefore, how to organically combine renewable energy output, energy storage management, and electrothermal synergy to maximize renewable energy consumption and economic benefits remains a key challenge that urgently needs to be overcome. Summary of the Invention

[0005] This invention provides a multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters to overcome the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: A method for multi-energy coordinated operation of photovoltaic-photothermal-electric heaters, comprising the following steps: S1. Construct a collaborative operation framework for a photovoltaic-photothermal-electric heater multi-energy system, wherein the photovoltaic-photothermal-electric heater multi-energy system includes: a photovoltaic power generation system, a solar thermal power generation system, and an electric heater; S2. Based on the aforementioned collaborative operation framework, establish a photovoltaic power model and curtailment constraints, a solar thermal power generation model and power constraints, and an electric heater operation model and power constraints; S3. Design the start-up and shutdown control model and equipment switching constraints for the concentrated solar power (CSP) system; S4. Construct an ancillary service model and power constraints to measure the ancillary service capabilities of a concentrated solar power (CSP) system; S5. To maximize the total annual revenue of the photovoltaic-solar-electric heater multi-energy system, a collaborative optimization scheduling model is constructed, and several constraints are set. The total revenue is determined based on electricity sales revenue, revenue from participating in the ancillary services market, and costs. The constraints include photovoltaic power model and curtailment constraints, solar thermal power generation model and power constraints, electric heater operation model and power constraints, solar thermal power generation system start-up and shutdown control model and equipment switching constraints, and ancillary service model and power constraints. S6. Solve the cooperative optimization scheduling model to obtain the multi-energy cooperative optimal scheduling scheme for the whole year. Furthermore, the photovoltaic power model and curtailment constraints established based on the aforementioned collaborative operation framework include: Set the output of the photovoltaic power generation system to anyt The time frame includes three parts: directly connected grid-connected power for sale. Power supplied via electric heater and abandoned power Furthermore, since all three satisfy the law of conservation of energy, the photovoltaic power model can be expressed as follows: (1) in, express t The actual available photovoltaic output at any given time; The power output of a photovoltaic power generation system is determined by the installed capacity of the photovoltaic system. Constraints are represented as: (2) The requirement that photovoltaic power generation must meet grid dispatch constraints, i.e., curtailment constraints, is expressed as follows: (3) in, This is the set proportional constant.

[0007] Furthermore, the concentrated solar power generation model and power constraints established based on the aforementioned collaborative operation framework include: The solar thermal power generation model is represented as follows: (4) in, This indicates the heat power transferred from the collector to the heat transfer fluid. This represents the heat power transferred from the heat storage unit to the heat transfer fluid. This represents the heat power transferred by the heat transfer fluid to the heat storage unit. This represents the heat power transferred by the heat transfer fluid to the power generation unit for power generation. This is the start-up signal for the solar thermal power unit at time t. The amount of heat required for each startup of a concentrated solar power (CSP) system. Energy efficiency of electric heaters; All power variables are assumed to be non-negative, and the heat collection power cannot exceed the predicted maximum available value. , represented as: (5) (6) (7) in, Indicates the heat rejection capacity of the solar collector; Setting the power output of the solar thermal power generation system for: (8) in, For the thermoelectric conversion efficiency of solar thermal power generation; express t The heat power of the heat transfer fluid is constantly transferred to the power generation unit for power generation. The power output of a concentrated solar power (CSP) system is constrained by the installed capacity and the minimum stable output, expressed as: (9) in, Indicates the installed capacity of a solar thermal power plant. Indicates the minimum output power of photothermal energy; It is a binary variable; Setting the state transition relationship of the thermal storage unit includes the initial time. and regular times The two cases are represented as follows: (10) , (11) in, This represents the thermal energy stored in the thermal storage unit at the initial moment; express t The thermal energy stored in the thermal storage unit at all times; This represents the initial value of the solar thermal storage state transition relationship; express t The thermal energy stored in the thermal storage unit at time -1; This represents the heat power transferred by the heat transfer fluid to the heat storage unit at the initial moment; This represents the heat power transferred from the heat storage unit to the heat transfer fluid at the initial moment; Indicates the heat storage and charging efficiency of solar thermal energy; express t The heat power transferred by the heat transfer fluid to the heat storage unit at all times; express t The heat power that the heat storage unit transfers to the heat transfer fluid at all times; Indicates the scheduling time interval; The charge / discharge heat power and state transition relationship of the thermal storage unit are set to be limited by the maximum / minimum capacity, expressed as: (12) (13) in, This indicates the maximum heat release power of solar thermal storage. This indicates the maximum charging power of the solar thermal storage. Thermal storage level of thermal storage unit Limited by the capacity of solar thermal energy storage, it can be expressed as: (14) in, This indicates the upper limit of solar thermal storage capacity. This indicates the lower limit of solar thermal storage capacity.

[0008] Furthermore, the electric heater operation model and power constraints established based on the aforementioned collaborative operation framework include: The electric heater is configured to only absorb surplus electricity from the photovoltaic power generation system. The operating model of the electric heater is represented as follows: (15) in, Energy efficiency of electric heaters; express t The heat power that the electric heater transfers to the heat transfer fluid at any given moment; The power constraint for the electric heater is set as follows: (16) in, This indicates the installed capacity of the electric heater.

[0009] Furthermore, the start-up and shutdown control model and equipment switching constraints of the designed concentrated solar power (CSP) system include: Assuming the solar thermal unit is in t Start signal at time ,right After linearization, it is represented as: (17) Set a constraint on the number of device switching times per day, expressed as follows: (18) in, For binary decision variables, defined as: (19) in, express t Real-time operating status of the solar thermal power unit; express t -1 is the operating status of the solar thermal power unit; when When, it indicates that the status of the solar thermal power unit has changed during that period. When the time is specified, it indicates that the state of the solar thermal power unit remains unchanged during that period.

[0010] Furthermore, in S4, the ancillary service model and power constraints constructed to measure the ancillary service capabilities of a concentrated solar power (CSP) system include: S41. The ancillary services model used to measure the ability of a concentrated solar power (CSP) system to participate in ancillary services is defined as follows: (20) The power constraint is expressed as: (twenty one) (twenty two) in, Indicates the power sold. Indicates the power purchased by the power grid; This indicates the conversion factor for plant power consumption; S42. The conditions for measuring the ability to upgrade ancillary services are expressed as follows: (twenty three) in, This indicates an increase in power.

[0011] S43. The conditions for measuring the ability to downgrade ancillary services are expressed as follows: (twenty four) S44. Constraining auxiliary service variables to be non-negative is expressed as follows: (25).

[0012] Furthermore, the constructed collaborative optimization scheduling model is expressed as: (26) in, Indicates the electricity sales price. Indicates the electricity purchase price. This indicates an increase in electricity prices. This indicates a reduction in electricity prices. This indicates the unit price of water used by the plant. Concentrated solar power generation water consumption factor Indicates the unit price of water used by the plant; Represents revenue from electricity sales; This indicates revenue generated from participation in the ancillary services market; Indicates the cost of purchasing electricity; This represents the cost of water used by the plant. Beneficial effects: This invention addresses the practical operation and optimization needs of multi-energy systems in large-scale new energy bases. It constructs a collaborative operation framework for a photovoltaic-solar thermal-electric heater multi-energy system, and establishes photovoltaic power models and curtailment constraints, solar thermal power generation models and power constraints, and electric heater operation models and power constraints based on this framework. It also designs a start-stop control model and equipment switching constraints for the solar thermal power generation system, as well as an ancillary service model and power constraints to measure the system's ability to participate in ancillary services. Finally, with the goal of maximizing the total annual revenue of the photovoltaic-solar thermal-electric heater multi-energy system, a collaborative optimization scheduling model is constructed, and several constraints are set. By solving the collaborative optimization scheduling model, the optimal multi-energy collaborative scheduling scheme for the entire year is obtained. This invention proposes a multi-energy collaborative optimization scheduling method for photovoltaic-photothermal-electric heaters based on real physical constraints, operational state logic, and market rules. This method significantly improves the economy, flexibility, and controllability of multi-energy systems and effectively overcomes the technical bottlenecks of existing models, such as single objective and insufficient physical coupling. It has broad engineering application prospects and industrial promotion value. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a flowchart of a multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to the present invention; Figure 2 This is a framework diagram of the coordinated operation of the photovoltaic-photothermal-electric heater multi-energy system in an embodiment of the present invention. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] To address the shortcomings and optimization needs of existing technologies, this embodiment provides a multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters. This method focuses on the structural optimization, energy flow modeling, dynamic operational constraints, and market responsiveness of multi-energy systems in typical scenarios of large-scale new energy bases. Figure 1 As shown, the specific steps include: S1. Construct a collaborative operation framework for a photovoltaic-photothermal-electric heater multi-energy system, wherein the photovoltaic-photothermal-electric heater multi-energy system includes: a photovoltaic power generation system, a solar thermal power generation system, and an electric heater; Specifically, this embodiment comprehensively analyzes the system structure and energy flow paths of the new energy base, clarifies the energy flow and operational interactions between various energy units, and thus constructs a system as follows: Figure 2The highly integrated, multi-energy complementary, and flexibly adjustable photovoltaic-thermal-electric heater multi-energy system collaborative operation framework shown achieves efficient energy flow and optimized configuration between electrical and thermal energy. The main energy flow paths and coupling relationships within this system include: (1) Part of the electricity output by the photovoltaic power generation system can be directly connected to the grid for sale, while the other part of the electricity is converted into heat energy through electric heaters to provide supplementary heat for the thermal storage unit or solar thermal system, further enhancing the new energy absorption capacity and flexible adjustment space; (2) The solar thermal power generation system collects solar heat through a collector. The heat energy can be time-shifted and balanced through a thermal storage unit, and then converted into electrical energy through a power generation unit, which smooths the fluctuation of photovoltaic output and achieves higher output stability. (3) The thermal storage unit in the solar thermal power generation system has the ability to regulate both heat charging and heat dissipation. It can absorb surplus solar thermal and photovoltaic power, and can also flexibly support the heat demand of the power generation unit, so as to realize the optimized utilization of energy across time periods. (4) As an external energy interaction platform, the power grid can both purchase electricity from the system to supplement the shortage and accept the system's surplus electricity to support the overall energy flow balance and economic optimization. (5) The solar thermal power generation sector supports participation in the ancillary services market, including system peak shaving (power up) and response down, to provide additional revenue and operational safety guarantees for the new energy base.

[0017] (6) The optimization method proposed in this embodiment supports the optimization modeling and simulation solution of 8760 hours of hourly operation data, covering the analysis of multi-dimensional operation characteristics such as energy flow, power balance, ancillary services and economic benefits among photovoltaic, solar thermal, electric heating, thermal storage, power grid and ancillary services.

[0018] S2. Based on the aforementioned collaborative operation framework, establish a photovoltaic power model and curtailment constraints, a solar thermal power generation model and power constraints, and an electric heater operation model and power constraints; Specifically, this embodiment employs a hierarchical modeling and constraint integration approach to systematically express the power output, energy flow, and dynamic coupling relationships among various types of equipment, including: S21. Establishing a photovoltaic power model and curtailment constraints Set the output of the photovoltaic power generation system to any t The time can be divided into three parts: directly grid-connected power for sale. Power supplied via electric heater and abandoned power Since the three satisfy the law of conservation of energy, the photovoltaic power model is defined as follows: (1) in, expresst The actual available photovoltaic output at any given time; The power output of a photovoltaic power generation system is determined by the installed capacity of the photovoltaic system. Constraints are represented as: (2) To prevent excessive curtailment of photovoltaic (PV) power generation, PV power generation must meet grid dispatch constraints, i.e., curtailment constraints are expressed as: (3) in, The set proportionality constant is set to 0.4 in this embodiment; S22. Concentrated Solar Power Generation Model and Power Constraints In a specific embodiment, such as Figure 2 As shown, a concentrated solar power (CSP) system mainly includes a solar collector (SF), a high-temperature heat transfer fluid (HTF), a thermal energy storage unit (TES), and a power generation unit (PB). The multi-energy flow and thermal energy conservation relationships of the CSP system are established, and the CSP model is expressed as follows: (4) in, This indicates the heat power transferred from the collector to the heat transfer fluid. This represents the heat power transferred from the heat storage unit to the heat transfer fluid. This represents the heat power transferred by the heat transfer fluid to the heat storage unit. This represents the heat power transferred by the heat transfer fluid to the power generation unit for power generation. This is the start-up signal for the solar thermal power unit at time t. The amount of heat required for each startup of a concentrated solar power (CSP) system. Energy efficiency of electric heaters; All power variables are assumed to be non-negative, and the heat collection power cannot exceed the predicted maximum available value. , represented as: (5) (6) (7) in, Indicates the heat rejection capacity of the solar collector; Setting the power output of the solar thermal power generation system for: (8) in, For the thermoelectric conversion efficiency of solar thermal power generation; express t The heat power of the heat transfer fluid is constantly transferred to the power generation unit for power generation. The power output of a concentrated solar power (CSP) system is constrained by the installed capacity and the minimum stable output, expressed as: (9) in, Indicates the installed capacity of a solar thermal power plant. Indicates the minimum output power of photothermal energy; It is a binary variable used to control the start and stop of the solar thermal power unit; Setting the State of Occurrence (SOC) relationship of the thermal storage unit includes the initial time. and regular times The two cases are represented as follows: (10) , (11) in, This represents the thermal energy stored in the thermal storage unit at the initial moment; express t The thermal energy stored in the thermal storage unit at all times; This represents the initial SOC value of the solar thermal storage. express t The thermal energy stored in the thermal storage unit at time -1; This represents the heat power transferred by the heat transfer fluid to the heat storage unit at the initial moment; This represents the heat power transferred from the heat storage unit to the heat transfer fluid at the initial moment; Indicates the heat storage and charging efficiency of solar thermal energy; express t The heat power transferred by the heat transfer fluid to the heat storage unit at all times; express t The heat power that the heat storage unit transfers to the heat transfer fluid at all times; Indicates the scheduling time interval; The charge / discharge power and SOC of the thermal storage unit are limited by the maximum / minimum capacity, as follows: (12) (13) in, This indicates the maximum heat release power of solar thermal storage. This indicates the maximum charging power of the solar thermal storage. In addition, the thermal storage level of the thermal storage unit Limited by the capacity of solar thermal energy storage, it can be expressed as: (14) in, This indicates the upper limit of solar thermal storage capacity. This indicates the lower limit of solar thermal storage capacity.

[0019] S23. Electric Heater Operation Model and Power Constraints In this embodiment, the electric heater is configured to only absorb surplus power from the photovoltaic power generation system, and the operating model of the electric heater is represented as follows: (15) in, Energy efficiency of electric heaters; express t The heat power that the electric heater transfers to the heat transfer fluid at any given moment; The power constraint for the electric heater is set as follows: (16) in, This indicates the installed capacity of the electric heater.

[0020] Specifically, this embodiment proposes a power characteristic and physical modeling method for each device in a multi-energy system, including hourly power models for photovoltaic power generation, solar thermal power generation, electric heaters and thermal storage units. It also considers the actual operating characteristics of the devices, such as energy conversion efficiency, installed capacity, start-up and shutdown constraints, and thermal storage SOC, to form a unified optimized expression for multiple devices, multiple energy flows and multiple time periods.

[0021] This embodiment establishes multi-dimensional operational constraints such as photovoltaic curtailment rate, electric heater energy absorption, and ancillary service capacity: In response to the problem of absorbing a high proportion of new energy power generation, it sets an upper limit for the annual photovoltaic curtailment rate, the maximum power of the electric heater, and system ancillary service (upward and downward) capacity constraints to realize the system's flexible response and collaborative optimization to the electricity market and ancillary service market.

[0022] S3. Design the start-up and shutdown control model and equipment switching constraints for the concentrated solar power (CSP) system; In a specific embodiment, the start-up and shutdown control model and equipment switching constraints of the designed concentrated solar power (CSP) system include: Assuming the solar thermal unit is in t Start signal at time ,right After linearization, it is represented as: (17) Set a constraint on the number of device switching times per day, expressed as follows: (18) in, It is the dth working day; For binary decision variables, defined as: (19) Specifically, express t Real-time operating status of the solar thermal power unit; express t -1 is the operating status of the solar thermal power unit; when When, it indicates that the status of the solar thermal power unit changes during that period (i.e., start-up or shutdown). When the time is specified, it indicates that the state of the solar thermal power unit remains unchanged during that period.

[0023] Specifically, this embodiment innovatively designs the start-up and shutdown logic and equipment switching constraints for solar thermal power generation. By introducing binary decision variables for the start-up and shutdown of solar thermal units, setting the maximum number of start-ups and shutdowns per day and the start-up heat consumption constraints, the safety and economy of equipment operation are ensured, and the overall adjustment flexibility of the multi-energy system is improved.

[0024] S4. Construct an ancillary service model and power constraints to measure the ancillary service capabilities of a concentrated solar power (CSP) system; To achieve flexible adjustment and enhanced revenue generation for multi-energy systems, this embodiment models the ancillary service capabilities of concentrated solar power (CSP) plants, including: S41. The ancillary services model used to measure the ability of a concentrated solar power (CSP) system to participate in ancillary services is defined as follows: (20) The power constraint is expressed as: (twenty one) (twenty two) in, Indicates the power sold. Indicates the power purchased by the power grid; This indicates the conversion factor for plant power consumption; S42. The conditions for measuring the ability to increase auxiliary services (increase output) are expressed as follows: (twenty three) in, This indicates an increase in power.

[0025] S43. The conditions for measuring the reduction in ancillary service capacity (reduced output) are expressed as follows: (twenty four) S44. Constraining auxiliary service variables to be non-negative is expressed as follows: (25).

[0026] S5. To maximize the total annual revenue of the photovoltaic-solar-electric heater multi-energy system, a collaborative optimization scheduling model is constructed, and several constraints are set. The total revenue is determined based on electricity sales revenue, revenue from participating in the ancillary services market, and costs. The constraints include photovoltaic power model and curtailment constraints, solar thermal power generation model and power constraints, electric heater operation model and power constraints, solar thermal power generation system start-up and shutdown control model and equipment switching constraints, and ancillary service model and power constraints. S6. Solve the cooperative optimization scheduling model to obtain the optimal multi-energy cooperative scheduling scheme for the whole year. In a specific embodiment, the constructed collaborative optimization scheduling model is represented as follows: (26) in, Indicates the electricity sales price. Indicates the electricity purchase price. This indicates an increase in electricity prices. This indicates a reduction in electricity prices. This indicates the unit price of water used by the plant. Concentrated solar power generation water consumption factor Indicates the unit price of water used by the plant; Represents revenue from electricity sales; This indicates revenue generated from participation in the ancillary services market; Indicates the cost of purchasing electricity; This indicates the cost of water used by the plant.

[0027] Specifically, this embodiment takes maximizing total annual revenue as its core objective and comprehensively considers various economic factors such as electricity sales revenue, electricity purchase cost, ancillary service market revenue, and operation and maintenance costs to construct a collaborative optimization scheduling model.

[0028] Specifically, this embodiment uses the mixed-integer linear programming (MILP) method to model and solve the above-mentioned multi-energy synergistic optimization problem, achieving optimal scheduling throughout the year. This provides theoretical and methodological support for the actual operation and engineering promotion of multi-energy systems in large-scale new energy bases. The specific output results after solving include: (1) Output, energy flow and heat storage levels of all equipment in each time period; (2) Detailed breakdown of total annual profit, costs, and revenues; (3) Support service capabilities and market participation in different time periods; (4) Statistics on operating characteristics such as start-up and shutdown times, start-up heat consumption, power curtailment rate, and thermal storage liquid level to support engineering applications and subsequent decision analysis.

[0029] In summary, this embodiment addresses the operational realities and optimization needs of multi-energy systems in large-scale new energy bases. It proposes a multi-energy collaborative optimization scheduling method for photovoltaic-photothermal-electric heaters based on the coupling of real physical constraints, operational state logic, and market rules. This method significantly improves the economy, flexibility, and controllability of multi-energy systems, effectively overcoming the technical bottlenecks of existing models such as single objectives and insufficient physical coupling. It has broad engineering application prospects and industrial promotion value.

[0030] Specifically, in terms of theoretical research, this invention systematically constructs a collaborative optimization operation framework for a photovoltaic-solar thermal-electric heater multi-energy system oriented towards large-scale new energy bases. It innovatively integrates energy flow modeling, power characteristic expression, and dynamic operation constraints of photovoltaic power generation, solar thermal power generation, electric heaters, and thermal storage units, providing a rigorous mathematical foundation and modeling paradigm for the optimal scheduling of multi-energy complementary systems. The proposed all-time economic optimization method for multi-energy systems not only balances the efficient absorption of new energy with the maximization of system economic benefits, but also provides a systematic approach and empirical model for academic and engineering research on the optimal scheduling, flexibility improvement, and ancillary service market response of large-scale multi-energy systems, filling a gap in the theory and methodology of related fields.

[0031] From the perspective of technology promotion and application, this embodiment establishes a complete model of the physical constraints, energy flow balance, and equipment operation status of a photovoltaic-photothermal-electric heater multi-energy system, significantly improving the feasibility of multi-energy system collaborative optimization and practical engineering applications. It can meticulously characterize the operating characteristics, power balance, and start-up and shutdown strategies of various types of equipment throughout the year and at multiple time periods. Driven by economic objectives, it comprehensively considers multiple factors such as power generation revenue, ancillary service revenue, and operation and maintenance costs to achieve optimal improvement in the operating efficiency of the multi-energy system. The optimization results can provide scientific decision-making support for practical scenarios such as large-scale new energy base engineering demonstrations, regional energy management, and market-oriented operation, facilitating industry promotion, experience replication, and large-scale application.

[0032] Furthermore, the multi-energy coordinated operation and optimization method in this embodiment has good compatibility and scalability, and can flexibly introduce new energy sources or loads such as wind power, energy storage, and demand-side response according to actual scenarios, realizing dynamic expansion and functional upgrades of the system. By establishing a standardized multi-energy system optimization framework, it will help promote the formulation of industry standards and the dissemination of advanced experiences in new energy multi-energy complementary systems, providing solid theoretical and technical support for the healthy development of my country's large-scale new energy bases and multi-energy coordinated demonstration projects.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for multi-energy coordinated operation of photovoltaic-photothermal-electric heaters, characterized in that, The specific steps include: S1. Construct a collaborative operation framework for a photovoltaic-photothermal-electric heater multi-energy system, wherein the photovoltaic-photothermal-electric heater multi-energy system includes: a photovoltaic power generation system, a solar thermal power generation system, and an electric heater; S2. Based on the aforementioned collaborative operation framework, establish a photovoltaic power model and curtailment constraints, a solar thermal power generation model and power constraints, and an electric heater operation model and power constraints; S3. Design the start-up and shutdown control model and equipment switching constraints for the concentrated solar power (CSP) system; S4. Construct an ancillary service model and power constraints to measure the ancillary service capabilities of a concentrated solar power (CSP) system; S5. To maximize the total annual revenue of the photovoltaic-solar-electric heater multi-energy system, a collaborative optimization scheduling model is constructed, and several constraints are set. The total revenue is determined based on electricity sales revenue, revenue from participating in the ancillary services market, and costs. The constraints include photovoltaic power model and curtailment constraints, solar thermal power generation model and power constraints, electric heater operation model and power constraints, solar thermal power generation system start-up and shutdown control model and equipment switching constraints, and ancillary service model and power constraints. S6. Solve the cooperative optimization scheduling model to obtain the multi-energy cooperative optimal scheduling scheme for the whole year.

2. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 1, characterized in that, The photovoltaic power model and curtailment constraints established based on the aforementioned collaborative operation framework include: Set the output of the photovoltaic power generation system to any t The time frame includes three parts: directly connected grid-connected power for sale. Power supplied via electric heater and abandoned power Furthermore, since all three satisfy the law of conservation of energy, the photovoltaic power model can be expressed as follows: (1) in, express t The actual available photovoltaic output at any given time; The power output of a photovoltaic power generation system is determined by the installed capacity of the photovoltaic system. Constraints are represented as: (2) The requirement that photovoltaic power generation must meet grid dispatch constraints, i.e., curtailment constraints, is expressed as follows: (3) in, This is the set proportional constant.

3. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 2, characterized in that, The concentrated solar power generation model and power constraints established based on the aforementioned collaborative operation framework include: The solar thermal power generation model is represented as follows: (4) in, This indicates the heat power transferred from the collector to the heat transfer fluid. This represents the heat power transferred from the heat storage unit to the heat transfer fluid. This represents the heat power transferred by the heat transfer fluid to the heat storage unit. This represents the heat power transferred by the heat transfer fluid to the power generation unit for power generation. This is the start-up signal for the solar thermal power unit at time t. The amount of heat required for each startup of a concentrated solar power (CSP) system. Energy efficiency of electric heaters; All power variables are assumed to be non-negative, and the heat collection power cannot exceed the predicted maximum available value. , represented as: (5) (6) (7) in, Indicates the heat rejection capacity of the solar collector; Setting the power output of the solar thermal power generation system for: (8) in, For the thermoelectric conversion efficiency of solar thermal power generation; express t The heat power of the heat transfer fluid is constantly transferred to the power generation unit for power generation. The power output of a concentrated solar power (CSP) system is constrained by the installed capacity and the minimum stable output, expressed as: (9) in, Indicates the installed capacity of a solar thermal power plant. Indicates the minimum output power of photothermal energy; It is a binary variable; Setting the state transition relationship of the thermal storage unit includes the initial time. and regular times The two cases are represented as follows: (10) ， (11) in, This represents the thermal energy stored in the thermal storage unit at the initial moment; express t The thermal energy stored in the thermal storage unit at all times; This represents the initial value of the solar thermal storage state transition relationship; express t The thermal energy stored in the thermal storage unit at time -1; This represents the heat power transferred by the heat transfer fluid to the heat storage unit at the initial moment; This represents the heat power transferred from the heat storage unit to the heat transfer fluid at the initial moment; Indicates the heat storage and charging efficiency of solar thermal energy; express t The heat power transferred by the heat transfer fluid to the heat storage unit at all times; express t The heat power that the heat storage unit transfers to the heat transfer fluid at all times; Indicates the scheduling time interval; The charge / discharge heat power and state transition relationship of the thermal storage unit are set to be limited by the maximum / minimum capacity, expressed as: (12) (13) in, This indicates the maximum heat release power of solar thermal storage. This indicates the maximum charging power of the solar thermal storage. Thermal storage level of thermal storage unit Limited by the capacity of solar thermal energy storage, it can be expressed as: (14) in, Indicates the upper limit of solar thermal storage capacity. This indicates the lower limit of solar thermal storage capacity.

4. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 3, characterized in that, The electric heater operation model and power constraints established based on the aforementioned collaborative operation framework include: The electric heater is configured to only absorb surplus electricity from the photovoltaic power generation system. The operating model of the electric heater is represented as follows: (15) in, Energy efficiency of electric heaters; express t The heat power that the electric heater transfers to the heat transfer fluid at any given moment; The power constraint for the electric heater is set as follows: (16) in, This indicates the installed capacity of the electric heater.

5. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 4, characterized in that, The start-stop control model and equipment switching constraints of the designed concentrated solar power (CSP) system include: Assuming the solar thermal unit is in t Start signal at time ,right After linearization, it is represented as: (17) Set a constraint on the number of device switching times per day, expressed as follows: (18) in, For binary decision variables, defined as: (19) in, express t Real-time operating status of the solar thermal power unit; express t -1 is the operating status of the solar thermal power unit; when When, it indicates that the status of the solar thermal power unit has changed during that period. When the time is specified, it indicates that the state of the solar thermal power unit remains unchanged during that period.

6. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 1, characterized in that, In S4, the ancillary service model and power constraints constructed to measure the ancillary service capabilities of a concentrated solar power (CSP) system include: S41. The ancillary services model used to measure the ability of a concentrated solar power (CSP) system to participate in ancillary services is defined as follows: (20) The power constraint is expressed as: (21) (22) in, Indicates the power sold. Indicates the power purchased by the power grid; This indicates the conversion factor for plant power consumption; S42. The conditions for measuring the ability to upgrade ancillary services are expressed as follows: (23) in, This indicates an increase in power. 7.S43. The conditions for measuring the ability to downgrade ancillary services are expressed as follows: (24) S44. Constraining auxiliary service variables to be non-negative is expressed as follows: (25)。 8. The multi-energy coordinated operation method for photovoltaic-photothermal-electric heaters according to claim 1, characterized in that, The constructed collaborative optimization scheduling model is represented as follows: (26) in, Indicates the electricity sales price. Indicates the electricity purchase price. This indicates an increase in electricity prices. This indicates a reduction in electricity prices. This indicates the unit price of water used by the plant. Concentrated solar power generation water consumption factor Indicates the unit price of water used by the plant; Represents revenue from electricity sales; This indicates revenue generated from participation in the ancillary services market; Indicates the cost of purchasing electricity; This indicates the cost of water used by the plant.

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