Source-grid-load-storage optimal operation method and device considering conversion efficiency and attenuation cost

Abstract

A source-grid-load-storage optimization operation method and device considering conversion efficiency and attenuation cost, the method comprising: constructing a storage system model, the storage system model including a conversion efficiency segmented function of a bidirectional converter and a storage attenuation cost function including comprehensive cycle aging cost and calendar aging cost; constructing a source-grid-load-storage power grid optimization operation model with the minimum total operation cost of the source-grid-load-storage power grid as the target, the total operation cost of the source-grid-load-storage power grid including transaction cost of the source-grid-load-storage power grid and a superior external power grid and a heat grid, operation and maintenance cost of each device in the source-grid-load-storage power grid, and storage cost, carbon emission transaction cost and abandoned wind and light cost of the source-grid-load-storage power grid; and solving the source-grid-load-storage power grid optimization operation model to obtain the optimization operation result of the source-grid-load-storage power grid. The optimization operation result of the source-grid-load-storage power grid formed by the application can truly reflect the utilization of the storage system, and is helpful to improve the utilization rate of the storage system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power system planning and operation, and in particular to a source-grid-load-storage optimal operation method and device considering conversion efficiency and attenuation cost. BACKGROUND

[0002] The source-load mismatch problem caused by the volatility and uncertainty of new energy output brings great difficulty to the operation of the power grid. Energy storage devices provide a powerful tool for maintaining supply and demand balance and improving the flexibility of power grid operation.

[0003] For the optimal operation of the source-grid-load-storage power grid, one of the current research focuses is to realize the collaborative optimal operation of multiple energy forms such as electricity, heat and cold. The existing methods mostly use simplified energy storage models, ignoring the nonlinear relationship between the conversion efficiency of the bidirectional converter of the energy storage device and the charging and discharging power of the energy storage device, and ignoring the energy storage attenuation factor, which leads to an overestimation of the benefits of energy storage in the optimal operation of the source-grid-load-storage power grid, and the resulting energy storage utilization rate does not match the actual low-efficiency utilization of energy storage. The existing method cannot meet the needs of the optimal operation of the source-grid-load-storage power grid. And the existing detailed energy storage model is biased towards electrochemical equations and cannot be applied to the source-grid-load-storage power grid optimization equation.

[0004] With the rapid development of new energy, how to form a more detailed energy storage model and integrate it into the optimal operation of the source-grid-load-storage power grid is a problem that needs to be considered. SUMMARY

[0005] The purpose of the present application is to overcome the above-mentioned defects and problems in the prior art, and to provide a source-grid-load-storage optimal operation method and device considering conversion efficiency and attenuation cost. The source-grid-load-storage optimal operation result formed by the method can truly reflect the utilization of the energy storage system, and is helpful to improve the utilization rate of the energy storage system.

[0006] To achieve the above purpose, the technical solution of the present application is:

[0007] In a first aspect, the present application provides a source-grid-load-storage optimal operation method considering conversion efficiency and attenuation cost, comprising:

[0008] constructing an energy storage system model, the energy storage system model including a conversion efficiency piecewise function of a bidirectional converter and an energy storage attenuation cost function including a comprehensive cycle aging cost and a calendar aging cost;

[0009] An optimized operation model for the source-grid-load-storage grid is constructed with the goal of minimizing the total operating cost of the source-grid-load-storage grid. The total operating cost of the source-grid-load-storage grid includes the transaction costs between the source-grid-load-storage grid and the upper-level external power grid and heat network, the operation and maintenance costs of each device within the source-grid-load-storage grid, the energy storage cost of the source-grid-load-storage grid, the carbon emission trading cost, and the cost of wind and solar power curtailment.

[0010] Solve the source-grid-load-storage power grid optimization operation model to obtain the source-grid-load-storage power grid optimization operation results.

[0011] Preferably, the conversion efficiency piecewise function of the bidirectional converter is:

[0012] ;

[0013] Where, For the Energy storage systems in Charging power during the time period; For the Energy storage systems in AC power for charging during the time period; For the The efficiency of the bidirectional converter of the energy storage system; For the Energy storage systems in AC power discharged during the time period; For the Energy storage systems in The discharge power of the time period.

[0014] Preferably, a piecewise linearization method is used to approximate the relationship between the energy absorption capacity and energy state of the energy storage system, as shown below:

[0015] ;

[0016] Where, For the Energy storage systems in The amount of change in energy state within a time period; is the time step; For the Energy storage systems in Conversion efficiency of time period; For the Energy storage systems in Maximum discharge efficiency during a period of time;

[0017] In each time step, the impact of the charging and discharging behavior of the energy storage system on its energy state is:

[0018] ;

[0019] wherein, is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; is the efficiency of the bidirectional converter of the nth energy storage system in the discharge direction; and are the upper and lower energy state limits of the nth energy storage system, respectively; is the energy state of the nth energy storage system at the initial time period; is the initial energy state of the nth energy storage system. is the energy state of the nth energy storage system at the initial time period; is the initial energy state of the nth energy storage system.

[0020] Preferably, the calendar aging cost is:

[0021] ;

[0022] ;

[0023] ;

[0024] wherein, is the calendar aging cost of the nth energy storage system at the tth time period; is the replacement cost of the nth energy storage system; is the expected lifetime of the nth energy storage system; is the initial coefficient of calendar aging; is the incremental coefficient of calendar aging; is the energy state of the nth energy storage system at the tth time period; is the energy state of the nth energy storage system at the tth time period; and are the capacity cost coefficient and the power cost coefficient of the energy storage system, respectively; is the total duration of charging or discharging at the rated power at the rated energy storage level of the nth energy storage system; is the rated energy storage level of the nth energy storage system; is the rated power of the bidirectional converter. is the total duration of charging or discharging at the rated power at the rated energy storage level of the nth energy storage system; is the rated energy storage level of the nth energy storage system; is the rated power of the bidirectional converter.

[0025] ​​​​​​​​​Preferably, the comprehensive cycle aging cost is:

[0026] ;

[0027] ;

[0028] Where, For the The energy storage system is Degradation costs caused by cyclic charge and discharge of each segment; For the Replacement cost of an energy storage system; is the number of segments of the energy storage system cycle aging degradation model; The degradation stress function is proportional to the cycle depth. No. The value at the end point of each segment; The degradation stress function is proportional to the cycle depth. No. The value at the starting point of each segment; For the Energy storage systems in Aging costs caused by cyclic charge and discharge within a period of time; For the Energy storage systems in The first Battery discharge power in each segment; is the time step; is the degenerate stress function; It is the ratio of cycle depth to rated capacity.

[0029] Preferably, the objective function of the source-grid-load-storage-grid optimization operation model is:

[0030] ;

[0031] Where, is the total operating cost of the source-grid-load-storage grid; The transaction costs between the source grid, load grid, storage grid and the upper-level external grid and heat grid; The operation and maintenance costs of each device within the source-grid-load-storage grid; The energy storage cost for the source-grid-load-storage grid; The carbon emission trading cost of the source, grid, load and storage grid; The cost of curtailing wind and solar power in the source, grid, load, storage and grid;

[0032] The transaction costs between the source grid, load grid and storage grid and the upper external grid and heat grid for:

[0033] ;

[0034] Where, and They are The electricity purchase price and electricity sales price between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale prices of heat between the source, grid, load, storage, power grid and heat network during the time period; is the price of natural gas; and They are The amount of electricity purchased and sold between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale of heat between the source, grid, load, storage, power grid and heat network during the period; and They are Gas consumption of cogeneration units and gas boilers within the power grid of source, grid, load and storage during the time period;

[0035] The operation and maintenance costs of each device within the source-grid-load-storage grid for:

[0036] ;

[0037] Where, is the equipment operation coefficient; 、 、 、 、 、 、 They are the operating costs of photovoltaic power stations, wind turbines, combined heat and power units, power-to-gas devices, carbon capture devices, gas boilers, and solar thermal power stations; For the Photovoltaic power stations in Power generation during the time period; For the Wind turbines in Power generation during the time period; For the Combined heat and power units in Power generation during the time period; For the A power-to-gas device Electricity consumption during the time period; For the Carbon capture devices in Electricity consumption during the time period; For the Gas boilers in the output power of the nth thermal power station in the time period; the output power of the nth thermal power station in the time period; the output power of the nth thermal power station in the time period; the output power of the nth thermal power station in the time period;

[0038] the energy storage cost of the source-grid-load-storage power grid is:

[0039] ;

[0040] wherein, the total decay cost of the nth energy storage system in the time period; the total income of the nth energy storage system in the time period, including the income from electricity trading, capacity leasing, etc. brought by charging and discharging; the total income of the nth energy storage system in the time period, including the income from electricity trading, capacity leasing, etc. brought by charging and discharging; the total income of the nth energy storage system in the time period, including the income from electricity trading, capacity leasing, etc. brought by charging and discharging; the total income of the nth energy storage system in the time period, including the income from electricity trading, capacity leasing, etc. brought by charging and discharging; the total income of the nth energy storage system in the time period, including the income from electricity trading, capacity leasing, etc. brought by charging and discharging; the cost coefficient of the thermal storage system; the exchange heat power of the nth thermal storage system in the time period; the exchange heat power of the nth thermal storage system in the time period; the exchange heat power of the nth thermal storage system in the time period;

[0041] the carbon emission trading cost of the source-grid-load-storage power grid is:

[0042] ;

[0043] ;

[0044] wherein, the trading price of the nth carbon emission trading volume section; the trading price of the nth carbon emission trading volume section; the trading price of the nth carbon emission trading volume section; the trading price of the nth carbon emission trading volume section; the benchmark unit price of the carbon emission right; the incremental coefficient of the step price; the emission threshold corresponding to each step interval;

[0045] the curtailment cost of the source-grid-load-storage power grid is:

[0046] ;

[0047] wherein, the curtailment power of the source-grid-load-storage power grid in the time period; the curtailment penalty cost coefficient; the time step.

[0048] ​​​​Preferably, the constraints of the source-grid-load-storage-grid optimization operation model include electric power balance constraints and thermal power balance constraints;

[0049] The electric power balance constraint is:

[0050] ;

[0051] Where, For the CSP power stations in The electric power output during the time period; and Respectively wind turbines and Photovoltaic power stations in The actual power output value of the time period; For the source grid load storage grid The power purchased from the external power grid during the period; For the Combined heat and power units in Power generation during the time period; For the Energy storage systems in Discharge power during the time period; It is the first A normal load Power during the time period; For the A power-to-gas device Electricity consumption during the time period; For the Carbon capture devices in Electricity consumption during the time period; For the Energy storage systems in Charging power during the time period; For the source grid load storage grid The power sold to the external grid during the time period;

[0052] The thermal power balance constraint is:

[0053] ;

[0054] Where, For the Combined heat and power units in Heating power during the time period; For the Gas boilers in Heating power during the time period; For the A heat storage system a heat generation power of the time period; a heat consumption power of the time period for the nth heat storage system; a heat consumption power of the time period for the nth heat storage system; a heat consumption power of the time period for the nth heat storage system; a load power of the nth heat load in the source-grid-load-storage power grid.

[0055] In a second aspect, the present application provides a source-grid-load-storage optimal operation device considering conversion efficiency and attenuation cost, which is applied to the method described above, and the device comprises:

[0056] a storage system model construction module, configured to construct a storage system model, wherein the storage system model comprises a conversion efficiency segmented function of a bidirectional converter and a storage attenuation cost function comprising a comprehensive cycle aging cost and a calendar aging cost;

[0057] an optimal operation model construction module, configured to construct a source-grid-load-storage power grid optimal operation model with the minimum total operation cost of the source-grid-load-storage power grid as the target, wherein the total operation cost of the source-grid-load-storage power grid comprises a transaction cost of the source-grid-load-storage power grid with a superior external power grid and a heat grid, an operation and maintenance cost of each device in the source-grid-load-storage power grid, and a storage cost, a carbon emission transaction cost and a wind and light abandonment cost of the source-grid-load-storage power grid;

[0058] an optimal operation result acquisition module, configured to solve the source-grid-load-storage power grid optimal operation model to obtain an optimal operation result of the source-grid-load-storage power grid.

[0059] In a third aspect, the present application provides a source-grid-load-storage optimal operation device considering conversion efficiency and attenuation cost, comprising a memory and a processor.

[0060] The memory is configured to store computer program codes and transmit the computer program codes to the processor.

[0061] The processor is configured to execute the method described above according to instructions in the computer program codes.

[0062] In a fourth aspect, the present application provides a computer readable storage medium, wherein the computer readable storage medium stores computer programs, and the computer programs are executed by a processor to realize the method described above.

[0063] Compared with the prior art, the present application has the following beneficial effects:

[0064] ​The application is a kind of source network load storage optimization operation method and device considering conversion efficiency and attenuation cost, first, the energy storage system model is constructed, the energy storage system model includes the conversion efficiency segmented function of the bidirectional converter and the energy storage attenuation cost function including the comprehensive cycle aging cost and the calendar aging cost; then, the total operation cost of the source network load storage power grid is minimized as the target to construct the source network load storage power grid optimization operation model, the total operation cost of the source network load storage power grid includes the transaction cost of the source network load storage power grid and the superior external power grid and the heat network, the operation and maintenance cost of each device in the source network load storage power grid, and the energy storage cost, carbon emission transaction cost and abandoned wind and light cost of the source network load storage power grid; then, the source network load storage power grid optimization operation model is solved, and the optimization operation result of the source network load storage power grid is obtained. The source network load storage power grid optimization operation method provided by the application considers the conversion efficiency and attenuation cost of the energy storage system in the objective function and constraint condition of the source network load storage power grid optimization operation, and the optimization operation result of the source network load storage power grid formed can truly reflect the utilization of the energy storage system, which helps to improve the utilization rate of the energy storage system. BRIEF DESCRIPTION OF DRAWINGS

[0065] Figure 1 It is a flow chart of the source network load storage optimization operation method considering conversion efficiency and attenuation cost of the application.

[0066] Figure 2 It is an energy flow schematic diagram of the source network load storage power grid provided by the embodiment of the application.

[0067] Figure 3 It is a schematic diagram of the target area new energy output and electric heat load prediction result provided by the embodiment of the application.

[0068] Figure 4 It is a schematic diagram of the energy storage utilization rate considering conversion efficiency and attenuation cost provided by the embodiment of the application.

[0069] Figure 5 It is a structure block diagram of the source network load storage optimization operation device considering conversion efficiency and attenuation cost of the application.

[0070] Figure 6 It is a structure block diagram of the source network load storage optimization operation device considering conversion efficiency and attenuation cost of the application. DETAILED DESCRIPTION

[0071] The application is further described in detail in combination with the description and specific implementation of the accompanying drawings.

[0072] Reference Figure 1 The application provides a kind of source network load storage optimization operation method considering conversion efficiency and attenuation cost, comprising:

[0073] S1, a storage system model is constructed, the storage system model includes a conversion efficiency segmented function of a bidirectional converter and a storage attenuation cost function including comprehensive cycle aging cost and calendar aging cost;

[0074] S2, a source network load storage power grid optimization operation model is constructed with the minimum total operation cost of the source network load storage power grid as the target, the total operation cost of the source network load storage power grid includes the transaction cost of the source network load storage power grid and the superior external power grid and the heat network, the operation and maintenance cost of each device in the source network load storage power grid, and the storage cost, carbon emission transaction cost and abandoned wind and light cost of the source network load storage power grid;

[0075] S3, the source network load storage power grid optimization operation model is solved to obtain the optimization operation result of the source network load storage power grid.

[0076] The application first collects the new energy generation all-day data of the predicted typical day in the target area source network load storage power grid, the electric and heat load prediction all-day data, the transaction electricity price data and the carbon emission transaction price data; collects the equipment coefficients and operation and maintenance cost coefficients of the photovoltaic power station, the wind turbine generator set, the gas turbine, the electric gas device, the carbon capture device, the gas boiler and the photo-thermal power station in the current regional source network load storage power grid. Then a refined model of the storage system considering the conversion efficiency and capacity attenuation is formed, specifically including the fitting of the conversion efficiency segmented function of the bidirectional converter and the storage attenuation cost function of the comprehensive cycle aging and calendar aging. Then the conversion efficiency and attenuation cost of the storage system are considered to form the source network load storage power grid optimization operation objective function and constraint condition; the objective function of the source network load storage power grid optimization operation is to meet the lowest operation cost as much as possible under the condition of meeting various loads; the constraint condition of the source network load storage power grid optimization operation mainly includes the electric power balance constraint and the heat power balance constraint. Finally, the GUROBI solver is called in MATLAB to solve the source network load storage power grid optimization operation model to obtain the optimization operation result of the source network load storage power grid, including the purchase electricity cost, purchase gas cost, photo-thermal power station operation cost, storage cost, carbon transaction cost and total cost of the source network load storage power grid, and the dispatching power of the new energy, storage and load in the typical day. The source network load storage power grid optimization operation method provided by the application considers the conversion efficiency and attenuation cost of the storage system in the objective function and constraint condition of the source network load storage power grid optimization operation, and the optimization operation result of the source network load storage power grid can truly reflect the utilization of the storage system, which is helpful to improve the utilization rate of the storage system.

[0077] Further, the conversion efficiency segmented function of the bidirectional converter is fitted to form, when the storage system is in the charging state, that is, the bidirectional converter directly affects the rectified direct current charging power; when the storage system is in the discharging state, the bidirectional converter directly affects the alternating current discharging power, specifically:

[0078] ;

[0079] Where, For the Energy storage systems in Charging power during the time period; For the Energy storage systems in AC power for charging during the time period; For the The efficiency of the bidirectional converter of the energy storage system; For the Energy storage systems in AC power discharged during the time period; For the Energy storage systems in The discharge power of the time period.

[0080] Furthermore, the efficiency of a bidirectional converter is not constant but rather depends on the amount of power being transmitted. Under partial load conditions, the efficiency of a bidirectional converter is typically lower than under full load. Therefore, the efficiency model of a bidirectional converter exhibits nonlinear characteristics, which directly affect the actual efficiency of battery charging and discharging and the ultimate energy yield.

[0081] The relationship between the energy absorption capacity and energy state of the energy storage system is approximated by piecewise linearization, as shown below:

[0082] ;

[0083] Where, For the Energy storage systems in The amount of change in energy state within a time period; is the time step; For the Energy storage systems in Conversion efficiency of time period; For the Energy storage systems in The maximum discharge efficiency of the time period.

[0084] In order to embed the nonlinear efficiency curve of the bidirectional converter into the linear operation model, the SOS2 piecewise linear approximation method is adopted: first, several inflection points are pre-selected within the power range of the bidirectional converter, and a convex combination coefficient is introduced for each inflection point. The sum of all coefficients is required to be 1, and only the coefficients of two adjacent inflection points are allowed to be non-zero at the same time; then, the original efficiency function is replaced by the weighted sum of the efficiency value at the inflection point and its corresponding coefficient, so that the original curve is approximated by a straight line segment in each small interval. The above method can not only achieve high-precision approximation of efficiency curves of arbitrary shapes, but also fully preserve the linear structure of the model.

[0085] After the above piecewise linearization of the conversion efficiency, the impact of the charging and discharging behavior of the energy storage system on its energy state in each time step is:

[0086] ;

[0087] Where, For the Energy storage systems in Energy status of the time period; For the Energy storage systems in Energy status of the time period; For the The efficiency of the bidirectional converter of the energy storage system in the discharge direction; and Respectively The upper and lower limits of the energy state of the energy storage system; For the The energy state of the energy storage system in the initial period; For the The initial energy state of the energy storage system.

[0088] Based on the principle of battery energy conservation, the present invention first describes the relationship between the battery state of charge and the charging and discharging power input and output in an integral form in the continuous time domain. It assumes that the charging power and discharging power remain approximately constant within each fixed time period, and uses the rectangular approximation method to convert the above integral into a discrete form of "power multiplied by time". The battery round-trip efficiency coefficient is introduced into the charging energy term to reflect the actual energy stored in the battery during the charging process. Finally, based on the discretized energy increment expression, the upper limit constraints on the charging power and discharging power are derived in combination with the maximum charging energy increment and maximum discharge power of the battery design.

[0089] Furthermore, the energy storage degradation cost function includes the comprehensive cycle aging cost and calendar aging cost, specifically:

[0090] ;

[0091] Where, For the Energy storage systems in The decay cost of the time period; For the Energy storage systems in calendar aging cost of the time period; For the Energy storage systems in The aging cost caused by cyclic charge and discharge within a period of time.

[0092] Furthermore, calendar aging costs take into account the cost of battery degradation over time when the battery is not being charged or discharged. Specifically:

[0093] ;

[0094] ;

[0095] ;

[0096] Where, For the Energy storage systems in calendar aging cost of the time period; For the Replacement cost of an energy storage system; For the The expected lifespan of an energy storage system; is the initial coefficient of calendar aging; is the increment coefficient of calendar aging; For the Energy storage systems in Energy status during the time period; For the Energy storage systems in Energy status during the time period; and are the capacity cost coefficient and power cost coefficient of the energy storage system respectively; For the The total duration of charging or discharging of an energy storage system at rated power under rated storage capacity; For the Rated storage capacity of each energy storage system; is the rated power of the bidirectional converter.

[0097] Furthermore, the comprehensive cycle aging cost is given by piecewise linear approximation with different discharge depths, specifically:

[0098] ;

[0099] ;

[0100] Where, For the The energy storage system is Degradation costs caused by cyclic charge and discharge of each segment; For the Replacement cost of an energy storage system; is the number of segments of the energy storage system cycle aging degradation model, which is used to describe the degree of degradation; The degradation stress function is proportional to the cycle depth. No. The value at the end point of each segment; The degradation stress function is proportional to the cycle depth. No. The value at the starting point of each segment; For the Energy storage systems in Aging costs caused by cyclic charge and discharge within a time period; For the Energy storage systems in The first Battery discharge power in each segment; is the time step; is the degradation stress function, which describes the relationship between battery degradation and charge and discharge depth; It is the ratio of cycle depth to rated capacity.

[0101] Furthermore, the objective function of the source-grid-load-storage grid optimization operation model is:

[0102] ;

[0103] Where, is the total operating cost of the source-grid-load-storage grid; The transaction costs between the source grid, load grid, storage grid and the upper-level external grid and heat grid; The operation and maintenance costs of each device within the source-grid-load-storage grid; The energy storage cost for the source-grid-load-storage grid; The carbon emission trading cost of the source, grid, load and storage grid; The cost of curtailing wind and solar power in the source, grid, load, storage and grid;

[0104] The transaction costs between the source grid, load grid and storage grid and the upper external grid and heat grid for:

[0105] ;

[0106] Where, and They are The electricity purchase price and electricity sales price between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale prices of heat between the source, grid, load, storage, power grid and heat network during the time period; is the price of natural gas; and They are The amount of electricity purchased and sold between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale of heat between the source, grid, load, storage, power grid and heat network during the period; and They are Gas consumption of cogeneration units and gas boilers within the power grid of source, grid, load and storage during the time period;

[0107] The operation and maintenance costs of each device within the source-grid-load-storage grid for:

[0108] ;

[0109] Where, is the equipment operation coefficient; 、 、 、 、 、 、 They are the operating costs of photovoltaic power stations, wind turbines, combined heat and power units, power-to-gas devices, carbon capture devices, gas boilers, and solar thermal power stations; For the Photovoltaic power stations in Power generation during the time period; For the Wind turbines in Power generation during the time period; For the Combined heat and power units in Power generation during the time period; For the A power-to-gas device Electricity consumption during the time period; For the Carbon capture devices in Electricity consumption during the time period; For the Gas boilers in Output power during the time period; For the CSP power stations in Output power during the time period; is the total number of time periods;

[0110] The energy storage cost of the source grid load storage grid for:

[0111] ;

[0112] Where, For the Energy storage systems in Total cost of decay during the time period; For the Energy storage systems in Total revenue for the period; is the cost coefficient of the heat storage system; For the A heat storage system Exchange heat power during the period;

[0113] The carbon emission trading cost of the source grid load storage grid for:

[0114] ;

[0115] ;

[0116] Where, For the The transaction price of each carbon emissions trading volume segment; For the The carbon emission rights trading amount in each carbon emission trading volume segment; It is the benchmark unit price of carbon emission rights and determines the transaction price in the first-level range; It is the incremental coefficient of the tiered price, used to add a markup to the base unit price each time a tier is reached; The emission threshold corresponding to each step interval. If the emission threshold is exceeded, the next pricing level will be entered;

[0117] The cost of curtailing wind and solar power of the source, grid, load, storage and grid for:

[0118] ;

[0119] Where, For the source grid load storage grid The curtailed wind and solar power during the time period; Penalty cost coefficient for curtailing wind and solar power; is the time step.

[0120] Furthermore, the constraints of the source-grid-load-storage grid optimization operation model include electric power balance constraints and thermal power balance constraints;

[0121] The electric power balance constraint is:

[0122] ;

[0123] Where, For the CSP power stations in The electric power output during the time period; and are the actual power output values of the th wind turbine and the th photovoltaic power plant in the th time period, respectively; is the power purchase of the source-grid-load-storage power grid from the external grid in the th time period; is the power generation of the th combined heat and power unit in the th time period; is the discharging power of the th energy storage system in the th time period; is the power of the th conventional load in the source-grid-load-storage power grid in the th time period, wherein the “conventional load” refers to the basic electricity demand as an external input that cannot be scheduled, also known as basic load; it includes daily rigid electricity consumption (lighting, motors, air conditioning, etc.) of residential, commercial, industrial, and other users, but does not include flexible and schedulable loads (such as electric gas devices, carbon capture equipment, energy storage charging and discharging, etc.); is the power consumption of the th electric-to-gas device in the th time period; is the power consumption of the th carbon capture device in the th time period; is the charging power of the th energy storage system in the th time period; is the power sale of the source-grid-load-storage power grid to the external grid in the th time period;

[0124] The thermal power balance constraint is:

[0125] ;

[0126] In the formula, is the heat generation power of the th combined heat and power unit in the th time period; is the heat generation power of the th gas boiler in the th time period; is the heat generation power of the th heat storage system in the th time period; is the heat consumption power of the th heat storage system in the th time period; is the power of the The load power of the heat load.

[0127] In the source network load storage power grid optimization operation model, both the conversion efficiency and the attenuation cost are refined by coupling constraints and objective function items: (1) introducing the conversion efficiency. In the charge and discharge power constraints of the energy storage system, the bidirectional converter efficiency and the battery round-trip efficiency are multiplied respectively to accurately measure the net energy loss from the grid to the battery and from the battery to the grid; in the SOC (SOE) update constraint, the output energy item and the input energy item are multiplied by the corresponding efficiency coefficient, so that the optimization process automatically balances the reduction of available energy caused by efficiency loss. (2) Internalizing the attenuation cost. The calendar aging cost and the cycle aging cost are respectively established as a function form, wherein the calendar aging cost is linearly related to the average SOC, and the cycle aging cost is a power function of the cycle depth; in the objective function, the sum of the two is added as the "energy storage attenuation cost" item, which is minimized together with the grid transaction cost, the operation and maintenance cost, the carbon emission trading cost, the wind and light abandonment cost, etc.; by charging for each simulation depth and cycle behavior, the optimizer will spontaneously reduce the inefficient or high-loss charge and discharge operation, so as to realize the double balance of energy storage life consumption and efficiency loss in the optimization operation. In this way, the source network load storage power grid optimization operation model not only accurately measures the energy loss at the constraint level, but also internalizes the life consumption pricing at the target level, so that the final operation scheme can realize the optimal balance between efficiency, life and economy, and significantly improve the comprehensive utilization rate and operation economy of the energy storage system.

[0128] The method is described below by way of examples.

[0129] According to the energy flow schematic diagram of the source network load storage power grid given in the table Figure 2 The variable conditions of the target area are shown in Tables 1-4 as follows.

[0130] Table 1 Parameters of the energy storage system in the source network load storage power grid

[0131]

[0132] Table 2 Purchase and sale prices of the upper network

[0133]

[0134] Table 3 Piecewise linear approximation coordinates of the bidirectional converter efficiency curve

[0135]

[0136] Table 4 Rated capacity and characteristic coordinates of the energy storage system

[0137] ​

[0138] In Table 4, Indicates the rated capacity of the energy storage system; It represents the ratio of the energy that can be charged or discharged by the battery in a unit time period to its rated capacity. It describes the relative size of the battery's dispatchable energy relative to its rated capacity in each time period under different initial states of charge.

[0139] The forecast results of new energy output and electric heat load in the target area are collected as shown in the attached Figure 3 shown.

[0140] The source-grid-load-storage power grid optimization operation objective function and constraint conditions are formed taking into account the conversion efficiency and attenuation cost of the energy storage system, and the source-grid-load-storage power grid optimization operation results are calculated based on this.

[0141] The results of the power optimization of the power grid with multiple energy sources, grids, loads, and storage demonstrate that operators of the multi-energy coupled power grid, fully leverage their dynamic optimization scheduling capabilities under varying loads and electricity price gradients, achieving a balance between economic efficiency and low-carbon development through time-of-day energy allocation. During off-peak periods (00:00-7:00, 20:00-24:00), wind power and low-cost grid electricity are fully utilized to charge energy storage, while excess electricity is converted through power-to-gas technology for efficient resource utilization. During periods with moderate electricity prices (7:00-11:00, 14:00-18:00), CSP power plants are the primary source of clean energy to meet load demand, supplemented by appropriate discharge from energy storage to reduce reliance on electricity purchases. During peak periods (11:00-14:00, 18:00-20:00), energy storage discharge is used to reduce peak loads, while CSP and necessary cogeneration units are used to generate electricity to meet peak loads, minimizing high-priced grid electricity purchases. Overall, through the peak-shaving and valley-filling effect of energy storage and the strategy of smoothing the load curve, the utilization rate of clean energy is maximized, the operating costs are optimized, and carbon emissions are significantly reduced. At the same time, from the thermal energy optimization results of the source-grid-load-storage-grid network, it can be seen that the dynamic balance of the thermal load is achieved through the coordinated optimization of the heat storage system, the cogeneration unit and the gas boiler. Among them, the heat storage system also plays a role in peak-shaving and valley-filling, reducing the dependence on high-carbon heat sources, improving the efficiency of thermal energy utilization, reducing operating costs, and achieving a coordinated balance between economy and low carbon. In summary, after introducing the conversion efficiency of the bidirectional converter and the battery attenuation cost, the discharge power of the energy storage system during peak hours is significantly limited, and the charging during the valley period also takes into account the efficiency loss and life cost. The SOE curve shows a smooth transition between the various time periods, which truly reflects the comprehensive impact of efficiency loss and attenuation on the available capacity.

[0142] like Figure 4 As shown in Table 5, the trade-offs between technical performance and economic efficiency in different operating scenarios are clear at a glance, fully verifying that the source-grid-load-storage-grid optimized operation model accurately depicts the actual energy storage utilization rate.

[0143] Table 5 Cost of source network load storage power grid under different operation scenarios

[0144]

[0145] After the conversion efficiency of the bidirectional converter and the energy storage attenuation cost are taken into the optimization operation model, the charging amount in the low valley period and the discharging amount in the peak period are both reduced, and the state of charge curve is more smooth. Although the electricity and gas purchase costs only increase slightly, the refined use cost generated by efficiency loss and life consumption is greatly narrowed, resulting in an increase of about 200 yuan (about 1.2%) in total cost. This shows that only the conversion loss and attenuation effect are truly reflected in the optimization, the economic value of the energy storage system can be avoided to be overestimated, and then a feasible and economically reasonable scheduling scheme can be obtained.

[0146] Referring to Figure 5 The application further provides a source network load storage optimization operation device considering conversion efficiency and attenuation cost, which is applied to the source network load storage optimization operation method considering conversion efficiency and attenuation cost.

[0147] An energy storage system model construction module is configured to construct an energy storage system model, wherein the energy storage system model comprises a conversion efficiency segmented function of a bidirectional converter and an energy storage attenuation cost function comprising a comprehensive cycle aging cost and a calendar aging cost;

[0148] An optimization operation model construction module is configured to construct an optimization operation model of a source network load storage power grid with the minimum total operation cost of the source network load storage power grid as the target, wherein the total operation cost of the source network load storage power grid comprises a transaction cost of the source network load storage power grid and a superior external power grid and a heat network, an operation and maintenance cost of each device inside the source network load storage power grid, and an energy storage cost, a carbon emission transaction cost and a wind and light abandonment cost of the source network load storage power grid;

[0149] An optimization operation result acquisition module is configured to solve the optimization operation model of the source network load storage power grid to obtain an optimization operation result of the source network load storage power grid.

[0150] Referring to Figure 6 The application further provides a source network load storage optimization operation device considering conversion efficiency and attenuation cost, which comprises a memory and a processor.

[0151] The memory is configured to store computer program codes and transmit the computer program codes to the processor.

[0152] The processor is configured to execute the source network load storage optimization operation method considering conversion efficiency and attenuation cost according to the instructions in the computer program codes.

[0153] The application further provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the source network load storage optimization operation method considering conversion efficiency and attenuation cost.

[0154] Generally, the computer instructions used to implement the method of the present application can be carried by any combination of one or more computer readable storage media. The non-transitory computer readable storage medium can include any computer readable medium except a signal transiting temporarily.

[0155] The computer readable storage medium may, for example, be, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination of the above. More specific examples (a non-exhaustive list) of the computer readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this application, the computer readable storage medium can be any tangible medium that contains or stores a program that can be used by or in connection with an instruction execution system, apparatus or device.

[0156] The computer program code used to implement the present application can be written in one or more programming languages or combinations of languages including object oriented programming languages such as Java, Smalltalk, C++ or conventional procedural programming languages such as the "C" programming language or similar programming languages. In particular, Python language and platform frameworks based on TensorFlow, PyTorch, etc. suitable for neural network computing can be used. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0157] The above device and non-transitory computer readable storage medium can refer to the specific description of the source network load storage optimization operation method considering conversion efficiency and attenuation cost and its advantages, which will not be described here.

[0158] Although the embodiments of the present application have been shown and described above, it should be understood by those having ordinary skill in the art that the above embodiments are exemplary, and cannot be interpreted as limiting the present application, and those having ordinary skill in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A source-grid-load-storage optimization operation method taking into account conversion efficiency and attenuation cost, characterized in that: include: Constructing an energy storage system model, wherein the energy storage system model includes a piecewise function of conversion efficiency of a bidirectional converter and an energy storage attenuation cost function including a comprehensive cycle aging cost and a calendar aging cost; An optimized operation model for the source-grid-load-storage grid is constructed with the goal of minimizing the total operating cost of the source-grid-load-storage grid. The total operating cost of the source-grid-load-storage grid includes the transaction costs between the source-grid-load-storage grid and the upper-level external power grid and heat network, the operation and maintenance costs of each device within the source-grid-load-storage grid, the energy storage cost of the source-grid-load-storage grid, the carbon emission trading cost, and the cost of wind and solar power curtailment. Solving the source-grid-load-storage power grid optimization operation model to obtain the source-grid-load-storage power grid optimization operation result; The conversion efficiency piecewise function of the bidirectional converter is: ； Where, For the Energy storage systems in Charging power during the time period; For the Energy storage systems in AC power for charging during the time period; For the The efficiency of the bidirectional converter of the energy storage system; For the Energy storage systems in AC power discharged during the time period; For the Energy storage systems in Discharge power during the time period; The relationship between the energy absorption capacity and energy state of the energy storage system is approximated by piecewise linearization, as shown below: ； Where, For the Energy storage systems in The amount of change in energy state within a time period; is the time step; For the Energy storage systems in Conversion efficiency of time period; For the Energy storage systems in Maximum discharge efficiency during a period of time; In each time step, the impact of the charging and discharging behavior of the energy storage system on its energy state is: ； Where, For the Energy storage systems in Energy status of the time period; For the Energy storage systems in Energy status of the time period; For the The efficiency of the bidirectional converter of the energy storage system in the discharge direction; and Respectively The upper and lower limits of the energy state of the energy storage system; For the The energy state of the energy storage system in the initial period; For the The initial energy state of the energy storage system.

2. The source-grid-load-storage optimization operation method taking into account conversion efficiency and attenuation cost according to claim 1 is characterized in that: The calendar aging cost is: ； ； ； Where, For the Energy storage systems in calendar aging cost of the time period; For the Replacement cost of an energy storage system; For the The expected lifespan of an energy storage system; is the initial coefficient of calendar aging; is the increment coefficient of calendar aging; For the Energy storage systems in Energy status during the time period; For the Energy storage systems in Energy status during the time period; and are the capacity cost coefficient and power cost coefficient of the energy storage system respectively; For the The total duration of charging or discharging of an energy storage system at rated power under rated storage capacity; For the Rated storage capacity of each energy storage system; is the rated power of the bidirectional converter.

3. The source-grid-load-storage optimization operation method taking into account conversion efficiency and attenuation cost according to claim 1 is characterized in that: The comprehensive cycle aging cost is: ； ； Where, For the The energy storage system is Degradation costs caused by cyclic charge and discharge of each segment; For the Replacement cost of an energy storage system; is the number of segments of the energy storage system cycle aging degradation model; The degradation stress function is proportional to the cycle depth. No. The value at the end point of each segment; The degradation stress function is proportional to the cycle depth. No. The value at the starting point of each segment; For the Energy storage systems in Aging costs caused by cyclic charge and discharge within a period of time; For the Energy storage systems in The first Battery discharge power in each segment; is the time step; is the degenerate stress function; It is the ratio of cycle depth to rated capacity.

4. The source-grid-load-storage optimization operation method taking into account conversion efficiency and attenuation cost according to claim 1 is characterized in that: The objective function of the source-grid-load-storage grid optimization operation model is: ； Where, is the total operating cost of the source-grid-load-storage grid; The transaction costs between the source grid, load storage grid and the upper-level external grid and heat network; The operation and maintenance costs of each device within the source-grid-load-storage grid; The energy storage cost for the source-grid-load-storage grid; The carbon emission trading cost of the source, grid, load and storage grid; The cost of curtailing wind and solar power in the source, grid, load, storage and grid; The transaction costs between the source grid, load grid and storage grid and the upper external grid and heat grid for: ； Where, and They are The electricity purchase price and electricity sales price between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale prices of heat between the source, grid, load, storage, power grid and heat network during the time period; is the price of natural gas; and They are The amount of electricity purchased and sold between the source-grid-load-storage grid and the upper-level external grid during the time period; and They are The purchase and sale of heat between the source, grid, load, storage, power grid and heat network during the period; and They are Gas consumption of cogeneration units and gas boilers within the power grid of source, grid, load and storage during the time period; The operation and maintenance costs of each device within the source-grid-load-storage grid for: ； Where, is the equipment operation coefficient; 、 、 、 、 、 、 They are the operating costs of photovoltaic power stations, wind turbines, combined heat and power units, power-to-gas devices, carbon capture devices, gas boilers, and solar thermal power stations; For the Photovoltaic power stations in Power generation during the time period; For the Wind turbines in Power generation during the time period; For the Combined heat and power units in Power generation during the time period; For the A power-to-gas device Electricity consumption during the time period; For the Carbon capture devices in Electricity consumption during the time period; For the Gas boilers in Output power during the time period; For the CSP stations in Output power during the time period; The energy storage cost of the source grid load storage grid for: ； Where, For the Energy storage systems in Total cost of decay during the time period; For the Energy storage systems in Total revenue for the period; is the cost coefficient of the heat storage system; For the A heat storage system Exchange heat power during the period; The carbon emission trading cost of the source grid load storage grid for: ； ； Where, For the The transaction price of each carbon emissions trading volume segment; For the The carbon emission rights trading amount in each carbon emission trading volume segment; is the benchmark unit price of carbon emission rights; is the incremental coefficient of the step price; The emission threshold corresponding to each step interval; The cost of curtailing wind and solar power of the source, grid, load, storage and grid for: ； Where, For the source grid load storage grid The curtailed wind and solar power during the time period; Penalty cost coefficient for curtailing wind and solar power; is the time step.

5. The source-grid-load-storage optimization operation method taking into account conversion efficiency and attenuation cost according to claim 4 is characterized in that: The constraints of the source-grid-load-storage-grid optimization operation model include electric power balance constraints and thermal power balance constraints; The electric power balance constraint is: ； Where, For the CSP stations in The electric power output during the time period; and Respectively wind turbines and Photovoltaic power stations in The actual power output value of the time period; For the source grid load storage grid The power purchased from the external power grid during the period; For the Combined heat and power units in Power generation during the time period; For the Energy storage systems in Discharge power during the time period; It is the first A normal load Power during the time period; For the A power-to-gas device Electricity consumption during the time period; For the Carbon capture devices in Electricity consumption during the time period; For the Energy storage systems in Charging power during the time period; For the source grid load storage grid The power sold to the external grid during the time period; The thermal power balance constraint is: ； Where, For the Combined heat and power units in Heating power during the time period; For the Gas boilers in Heating power during the time period; For the A heat storage system Heating power during the time period; For the A heat storage system Heat consumption during the time period; It is the first The load power of a heat load.

6. A source-grid-load-storage optimization operation device taking into account conversion efficiency and attenuation cost, characterized in that: The device is applied to the method according to any one of claims 1 to 5, and the device comprises: An energy storage system model construction module is used to construct an energy storage system model, wherein the energy storage system model includes a piecewise function of conversion efficiency of a bidirectional converter and an energy storage attenuation cost function including a comprehensive cycle aging cost and a calendar aging cost; An optimization operation model construction module is used to construct an optimization operation model of the source-grid-load-storage power grid with the goal of minimizing the total operation cost of the source-grid-load-storage power grid. The total operation cost of the source-grid-load-storage power grid includes the transaction costs between the source-grid-load-storage power grid and the upper-level external power grid and heat network, the operation and maintenance costs of each equipment within the source-grid-load-storage power grid, and the energy storage costs, carbon emission trading costs, and wind and solar power curtailment costs of the source-grid-load-storage power grid; The optimization operation result acquisition module is used to solve the source-grid-load-storage power grid optimization operation model to obtain the optimization operation result of the source-grid-load-storage power grid.

7. A source-grid-load-storage optimized operation device taking into account conversion efficiency and attenuation cost, characterized in that: including memory and processor; The memory is configured to store computer program code and transmit the computer program code to the processor; The processor is configured to execute the method according to any one of claims 1 to 5 according to instructions in the computer program code.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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