Quotation method for photovoltaic-storage combined power station in the electricity spot market

Abstract

The present invention discloses a quotation method for a photovoltaic-storage combined power station in the electricity spot market. The technical solution adopted by the present invention includes: establishing three operation modes of energy storage units; constructing a photovoltaic-storage combined power station deviation assessment cost calculation model and an energy storage unit operation cost calculation model; according to the three operation modes of the energy storage unit, considering the energy storage unit operation cost and the photovoltaic-storage combined power station deviation assessment, taking the photovoltaic-storage combined power station market profit optimization as the objective function, establishing a quotation strategy model for the photovoltaic-storage combined power station to participate in the electricity spot market; constructing the constraint conditions of the quotation strategy model; solving the quotation strategy model to obtain the optimization parameters of the energy storage unit. The present invention effectively improves the income level of new photovoltaic-storage combined power stations participating in the electricity market while reducing the output fluctuation error of new energy and improving the ability of new photovoltaic-storage power stations to track the day-ahead dispatch plan.

Description

Technical Field

[0001] The invention relates to the field of power market bidding, in particular to a method for quoting a photovoltaic-storage combined power station in a power spot market. Background Art

[0002] With the proposal of the "carbon peak and carbon neutrality" goals, accelerating the transformation and upgrading of the power structure and achieving sustainable energy development has gradually become a social consensus. Against this background, a high proportion of renewable energy power generation and grid-connected systems dominated by wind power and photovoltaics will become an inevitable trend in the development of new power systems in the future. However, the scientific and effective operation of the electricity spot market is subject to the power supply and demand situation, power structure, grid characteristics, load characteristics, and insufficient flexible adjustment resources.

[0003] Energy storage is an effective means to solve the problem of renewable energy grid connection in an environment with a high proportion of new energy grid connection, and is an important technology and basic equipment to support the new power system. In the case that the electricity spot market mechanism is not yet mature, the revenue model of energy storage in the power market is still in the exploratory stage, so the economic feasibility of energy storage projects configured in new energy power stations is uncertain. With the advancement of power market reform, it is of great practical significance to explore new operating modes of energy storage and renewable energy, and to increase the benefits of new energy-storage combined power stations participating in the power market while ensuring the safety of the power grid. Summary of the invention

[0004] The purpose of the present invention is to address the problem of limited profit level of photovoltaic - energy storage combined power stations participating in the electricity spot market, and to provide a quotation method for photovoltaic - energy storage combined power stations in the electricity spot market, which can give play to the effective compensation of photovoltaic unit output fluctuations by energy storage equipment, improve the photovoltaic - energy storage combined power station's ability to track the day-ahead dispatch plan, and effectively improve the profit level of the photovoltaic - energy storage combined power station participating in the electricity spot market.

[0005] To this end, the technical solution of the present invention is implemented as follows: a price quotation strategy for a photovoltaic-storage combined power station in a power spot market, which includes the following steps:

[0006] Step 1: Establish three operation modes of energy storage units when the photovoltaic-storage combined power station participates in the electricity spot market;

[0007] Step 2: Construct a deviation assessment cost calculation model for the PV-storage combined power station participating in the electricity spot market and a storage unit operation cost calculation model;

[0008] Step 3: Based on the three operation modes of the energy storage unit, the operation cost of the energy storage unit and the deviation assessment of the photovoltaic-storage combined power station are considered, and the optimal market revenue of the photovoltaic-storage combined power station is taken as the objective function to establish the power market quotation strategy model;

[0009] Step 4: Construct the constraint conditions of the strategy model for the solar-storage combined power station to participate in the power market bidding;

[0010] Step 5: Solve the electricity market quotation strategy model to obtain the optimization parameters of the energy storage unit.

[0011] Furthermore, the specific content of step 1 is:

[0012] When a solar-storage combined power station participates in the electricity spot market, the three operating modes of the energy storage unit include:

[0013] Frequency regulation mode: Energy storage units participate in the frequency regulation auxiliary service market;

[0014] Main energy mode: energy storage units participate in the main energy market;

[0015] Smoothing mode: The energy storage unit is used to cope with excessive upward or downward fluctuations of the photovoltaic system of the power station through charging and discharging operation, so as to keep the fluctuation of the photovoltaic-storage combined power station within the permitted range of the power grid, including smooth charging mode and smooth discharging mode.

[0016] When constructing the power market quotation strategy model of the photovoltaic-storage combined power station, the operation mode of the energy storage unit is determined by introducing 0-1 auxiliary decision variables into the power market quotation strategy model. The specific auxiliary decision variables include:

[0017] When the value is 1, it means that the energy storage unit is in frequency modulation mode;

[0018] When the value is 1, it indicates that the energy storage unit is in smoothing (charging) mode;

[0019] When the value is 1, it means that the energy storage unit can choose to be in smoothing or main energy mode;

[0020] When the value is 1, it indicates that the energy storage unit is in the main energy mode;

[0021] When the value is 1, it indicates that the energy storage unit is in smoothing (discharging) mode.

[0022] Furthermore, the specific content of step 2 is: considering the impact of the cost of energy storage unit operation on its market participation income, and linearly simplifying the cost model to apply it to the market optimization model, the energy storage unit operation cost The calculation model is:

[0023]

[0024] Where N represents the total number of energy storage units; Soct,n It represents the state of charge of energy storage unit n at time t; a, b, c, d represent the coefficients of the energy storage unit operation cost calculation model; Dcr represents the discharge efficiency of the battery, and its physical meaning is the change in SOC between two moments.

[0025] Energy storage equipment can improve the dispatchability of photovoltaic units. The energy storage equipment configured in the photovoltaic-storage combined power station can adjust the deviation between the actual output of the new energy units and the day-ahead forecast through charging and discharging, thereby reducing the deviation assessment cost caused by the deviation of photovoltaic output.

[0026] Deviation assessment cost of solar-storage combined power station The calculation model is:

[0027]

[0028] In the formula, π pe σ is the proportional coefficient of deviation assessment of power generation plan execution of fixed output units; pe is the lower limit of the assessment price, λ t E is the node electricity price of the main energy market on the day before; P t S The power generation reported by the solar-storage combined power station on the previous day, P t ems The amount of electricity that the photovoltaic-storage combined power station actually participates in the main energy market; μ pe It is the allowable margin for deviation of power generation plan execution of fixed output units.

[0029] Furthermore, in the deviation assessment cost calculation model of the photovoltaic-storage combined power station, the photovoltaic-storage combined power station’s day-ahead reported power generation P t S The predicted output of photovoltaic power station P t solar_da ,Right now:

[0030] P t S =P t solar_da ,

[0031] The amount of electricity P that the photovoltaic-storage combined power station actually participates in the main energy market t ems for:

[0032] P t ems =P t solar_rt -P t pe+ +P t pe- ,

[0033] Where P t solar_rt represents the real-time photovoltaic output of the photovoltaic-storage combined power station; P t pe+ P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It indicates the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode.

[0034] Furthermore, the electricity spot market quotation strategy model in step 3 takes the optimal market revenue of the photovoltaic-storage combined power station as the objective function, and the specific formula is:

[0035]

[0036] In the formula, T represents the market time scale; represents the node electricity price in the main energy market on the day before, represents the frequency modulation market capacity price, represents the mileage price in the frequency modulation market; P t E represents the capacity of the energy storage unit participating in the main energy market at time t, P t F represents the capacity of energy storage units participating in the frequency regulation market at time t, Indicates the FM market call ratio; represents the operating cost of the energy storage unit, Represents the deviation assessment cost of the solar-storage combined power station.

[0037] Furthermore, the step 4 comprises:

[0038] Step 41: constructing SOC range constraints;

[0039]

[0040]

[0041] In the formula, Soc t,n Indicates the state of charge of energy storage unit n at time t; Soc lb Indicates the lower limit of the SOC level for switching the operation mode of the energy storage unit, Soc ub Indicates the upper limit of the SOC level for switching the operation mode of the energy storage unit; It is a 0-1 variable to assist decision making to ensure the uniqueness of the SOC range.

[0042] Step 42: constructing power constraints when the energy storage device is running in the main energy mode;

[0043]

[0044] Where P t E represents the capacity provided by the energy storage unit in the main energy market at time t; e rated Indicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0045] Step 43: Constructing power constraints when the energy storage device is running in frequency modulation mode;

[0046]

[0047] Where P t F represents the capacity provided by the energy storage unit in the frequency regulation market at time t; e rated Indicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0048] Step 44: constructing power constraints when the energy storage device is running in smoothing mode;

[0049] When the energy storage unit smoothes the PV output fluctuations through charging:

[0050]

[0051] When the energy storage unit smoothes the PV output fluctuations by discharging:

[0052]

[0053] When the SOC value of the energy storage unit is large, you can freely choose to be in smoothing or main energy market operation mode:

[0054]

[0055] Where P t pe+P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It represents the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; e rated Indicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0056] Furthermore, when solving the power market quotation strategy model in step 5, the optimization parameters calculated are:

[0057]

[0058] Among them, 0 and 1 represent the selection of energy storage operation mode, and obj is the overall profit value of the photovoltaic-storage combined power station participating in the electricity spot market.

[0059] The beneficial effects of the present invention are as follows: the present invention enables the energy storage system to select different operating modes according to its own operating status in the electricity spot market, can give full play to the effective compensation of the energy storage equipment for the output fluctuation of the photovoltaic unit, improve the tracking of the day-ahead scheduling plan of the photovoltaic-storage combined power station, and the proposed quotation strategy of the photovoltaic-storage combined power station can effectively improve its profit level from participating in the electricity spot market. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a schematic diagram of a quotation method for a photovoltaic-storage combined power station of the present invention;

[0061] Figure 2 It is a schematic diagram of three operating modes of the energy storage unit of the photovoltaic-storage combined power station of the present invention. DETAILED DESCRIPTION

[0062] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0063] like Figure 1 As shown, the present invention is a method for quoting a photovoltaic-storage combined power station in a power spot market, and the steps are as follows:

[0064] Step 1: Establishment of three operation modes of energy storage units when the PV-storage combined power station participates in the electricity spot market; the specific implementation process is: the energy storage system adjusts its operation mode during participation in the electricity spot market according to its state of charge (SOC), such as Figure 2 As shown, specifically including:

[0065] Frequency regulation mode: Energy storage units participate in the frequency regulation auxiliary service market;

[0066] Main energy mode: energy storage units participate in the main energy market;

[0067] Smoothing mode: The energy storage unit is used to cope with excessive upward or downward fluctuations of the photovoltaic system of the power station through charging and discharging operation, so as to keep the fluctuation of the photovoltaic-storage combined power station within the permitted range of the power grid.

[0068] When constructing the power market quotation strategy model of the photovoltaic-storage combined power station, the operation mode of the energy storage unit is determined by introducing 0-1 auxiliary decision variables into the power market quotation strategy model. The specific auxiliary decision variables include: When the value is 1, it means that the energy storage unit is in frequency modulation mode; When the value is 1, it indicates that the energy storage unit is in smoothing (charging) mode; When the value is 1, it means that when the SOC level of the energy storage unit is high, you can choose to be in smoothing or main energy mode; When the value is 1, it indicates that the energy storage unit is in the main energy mode; When the value is 1, it indicates that the energy storage unit is in smoothing (discharging) mode.

[0069] Step 2: Construct the deviation assessment cost calculation model for the PV-storage combined power station participating in the electricity spot market and the energy storage unit operation cost calculation model; the specific implementation process is: the loss cost generated by the operation of the energy storage unit will have a great impact on the overall revenue of the PV-storage combined power station participating in the electricity spot market. The energy storage cost model is linearly simplified and applied to the market optimization model. The energy storage unit operation cost The calculation model is:

[0070]

[0071] Where N represents the total number of energy storage units; Soc t,n It represents the state of charge of energy storage unit n at time t; a, b, c, d represent the coefficients of the energy storage unit operation cost calculation model; Dcr represents the discharge efficiency of the battery, and its physical meaning is the change in SOC between two moments.

[0072] Energy storage equipment can improve the dispatchability of photovoltaic units. The energy storage equipment configured in the photovoltaic-storage combined power station can adjust the deviation between the actual output of the new energy unit and the day-ahead forecast through charging and discharging, thereby reducing the deviation assessment cost caused by the deviation of photovoltaic output. Deviation assessment cost of photovoltaic-storage combined power station The calculation model is:

[0073]

[0074] In the formula, π pe σ is the proportional coefficient of deviation assessment of power generation plan execution of fixed output units; pe To assess the lower limit of the price, is the node electricity price of the main energy market on the day before; P t S The power generation reported by the solar-storage combined power station on the previous day, P t ems The amount of electricity that the photovoltaic-storage combined power station actually participates in the main energy market; μ pe It is the allowable margin for deviation of power generation plan execution of fixed output units.

[0075] In the deviation assessment cost calculation model of the photovoltaic-storage combined power station, the photovoltaic-storage combined power station’s reported power generation P t S The predicted output of photovoltaic power station P t solar_da ,Right now:

[0076] P t S =P t solar_da ,

[0077] The amount of electricity P that the photovoltaic-storage combined power station actually participates in the main energy market t ems for:

[0078] P t ems =P t solar_rt -P t pe+ +P t pe- ,

[0079] Where P t solar_rt represents the real-time photovoltaic output of the photovoltaic-storage combined power station; P t pe+ P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It indicates the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode.

[0080] Step 3: Based on the three operation modes of the energy storage unit, the established operation cost of the energy storage unit and the deviation assessment cost of the photovoltaic-storage combined power station, the optimal market revenue of the photovoltaic-storage combined power station is taken as the objective function to establish a power market quotation strategy model; the specific implementation process is: establish a photovoltaic-storage combined power station to participate in the power spot market quotation strategy model, the specific formula is:

[0081]

[0082] In the formula, T represents the market time scale; represents the node electricity price in the main energy market on the day before, represents the frequency modulation market capacity price, represents the mileage price in the frequency modulation market; P t E represents the capacity of the energy storage unit participating in the main energy market at time t, P t F represents the capacity of energy storage units participating in the frequency regulation market at time t, Indicates the FM market call ratio; represents the operating cost of the energy storage unit, Represents the deviation assessment cost of the solar-storage combined power station.

[0083] Step 4: Construct the constraint conditions of the solar-storage combined power station participating in the power market quotation strategy model; the specific implementation process is: the solar-storage combined power station participating in the power spot market quotation strategy model must meet the following constraints:

[0084] Step 41: constructing SOC range constraints;

[0085]

[0086]

[0087] In the formula, Soc t,n Indicates the state of charge of energy storage unit n at time t; Soc lb Indicates the lower limit of the SOC level for switching the operation mode of the energy storage unit, Soc ub Indicates the upper limit of the SOC level for switching the operation mode of the energy storage unit; It is a 0-1 variable to assist decision making to ensure the uniqueness of the SOC range.

[0088] Step 42: constructing power constraints when the energy storage device is running in the main energy mode;

[0089]

[0090] Where P t E represents the capacity provided by the energy storage unit in the main energy market at time t; erated Indicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0091] Step 43: Constructing power constraints when the energy storage device is running in frequency modulation mode;

[0092]

[0093] Where P t F represents the capacity provided by the energy storage unit in the frequency regulation market at time t; e rated Indicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0094] Step 44: constructing power constraints when the energy storage device is running in smoothing mode;

[0095] When the energy storage unit smoothes the PV output fluctuations through charging:

[0096]

[0097] When the energy storage unit smoothes the PV output fluctuations by discharging:

[0098]

[0099] When the SOC value of the energy storage unit is large, you can freely choose to be in smoothing or main energy market operation mode:

[0100]

[0101] Where P t pe+ P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It represents the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; e ratedIndicates the rated capacity of the energy storage unit; η dc Represents the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

[0102] Step 5: Solve the electricity market quotation strategy model to obtain the optimization parameters of the energy storage unit. The specific real-time process is: select a suitable programming language to program the electricity market quotation strategy model, and use a commercial solver to solve it. The optimization parameters obtained by calculation are:

[0103]

[0104] Among them, 0 and 1 represent the selection of energy storage operation mode, and obj is the overall profit value of the photovoltaic-storage combined power station participating in the electricity spot market.

[0105] The above description is only a description of the specific implementation process of the present invention in conjunction with the accompanying drawings. The above specific implementation method is not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A quotation method for a photovoltaic-storage combined power station in the electricity spot market, characterized in that: The following steps are involved: Step 1: Establish three operation modes of energy storage units when the photovoltaic-storage combined power station participates in the electricity spot market; Step 2: Construct a deviation assessment cost calculation model for the PV-storage combined power station participating in the electricity spot market and a storage unit operation cost calculation model; Step 3: Based on the three operation modes of the energy storage unit, the operation cost of the energy storage unit and the deviation assessment of the photovoltaic-storage combined power station are considered, and the optimal market revenue of the photovoltaic-storage combined power station is taken as the objective function to establish the power market quotation strategy model; Step 4: Construct the constraint conditions of the strategy model for the solar-storage combined power station to participate in the power market bidding; Step 5: Solve the power market quotation strategy model to obtain the optimization parameters of the energy storage unit; In the step 1, the three operation modes of the energy storage unit when the photovoltaic-storage combined power station participates in the electricity spot market include: frequency regulation mode: the energy storage unit participates in the frequency regulation auxiliary service market; Main energy mode: energy storage units participate in the main energy market; Smoothing mode: The energy storage unit uses charging and discharging operation modes to cope with excessive upward and downward fluctuations of the photovoltaic system of the photovoltaic-storage combined power station, so as to keep the fluctuation of the photovoltaic-storage combined power station within the permitted range of the power grid. The smoothing mode of the energy storage unit specifically includes smooth charging mode and smooth discharging mode; A 0-1 auxiliary decision variable is introduced to determine the operation mode of each energy storage unit, including: : When the value is 1, it means that the energy storage unit n is in the frequency modulation mode at time t; : When the value is 1, it means that the energy storage unit n is in smooth charging mode at time t; : When the value is 1, it means that the energy storage unit n can choose to be in smoothing mode or main energy mode at time t; : When the value is 1, it means that the energy storage unit n is in the main energy mode at time t; : When the value is 1, it means that the energy storage unit n is in smooth discharge mode at time t; In step 3, the power market quotation strategy model takes the optimal market revenue of the photovoltaic-storage combined power station as the objective function, and the specific formula is: In the formula, T represents the market time scale; represents the node electricity price in the main energy market on the day ahead, λ t FC represents the frequency modulation market capacity price, represents the mileage price in the frequency modulation market; P t E represents the capacity of the energy storage unit participating in the main energy market at time t, P t solar_rt represents the real-time photovoltaic output of the photovoltaic-storage combined power station at time t, P t F represents the capacity of energy storage units participating in the frequency regulation market at time t, Indicates the FM market call ratio; represents the operating cost of the energy storage unit, represents the deviation assessment cost of the solar-storage combined power station; The step 4 comprises: Step 41: constructing SOC range constraints; Step 42: constructing power constraints when the energy storage unit is operating in the main energy mode; Step 43: constructing power constraint conditions when the energy storage unit operates in frequency regulation mode; Step 44: Construct power constraints when the energy storage unit is running in smoothing mode.

2. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 1, characterized in that: The specific content of step 2 is: Energy storage unit operating costs The calculation model is: Where N represents the total number of energy storage units; Soc t,n represents the state of charge of energy storage unit n at time t; a, b, c, d represent the coefficients of the energy storage unit operation cost calculation model; Dcr represents the discharge efficiency of the battery, and its physical meaning is the change in SOC between two moments; Deviation assessment cost of solar-storage combined power station The calculation model is: In the formula, π pe σ is the proportional coefficient of deviation assessment of power generation plan execution of fixed output units; pe To assess the lower limit of the price, is the node electricity price of the main energy market on the day before; P t S The power generation reported by the solar-storage combined power station on the previous day, P t ems The amount of electricity that the photovoltaic-storage combined power station actually participates in the main energy market; μ pe It is the allowable margin for deviation of power generation plan execution of fixed output units.

3. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 2, characterized in that: In the deviation assessment cost calculation model, The photovoltaic-storage combined power station recently reported a power generation capacity of P t S The day-ahead photovoltaic output forecast P of the combined solar-storage power station t solar_da ,Right now: P t S =P t solar_da , The amount of electricity P that the photovoltaic-storage combined power station actually participates in the main energy market t ems for: P t ems =P t solar_rt -P t pe+ +P t pe- , Where P t solar_rt represents the real-time photovoltaic output of the photovoltaic-storage combined power station at time t; P t pe+ P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It indicates the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode.

4. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 1, characterized in that: The specific formula for constructing the SOC range constraint condition is: In the formula, Soc t,n Indicates the state of charge of energy storage unit n at time t; Soc lb Indicates the lower limit of the SOC level for switching the operation mode of the energy storage unit, Soc ub Indicates the upper limit of the SOC level for switching the operation mode of the energy storage unit; It is a 0-1 variable to assist decision making to ensure the uniqueness of the SOC range.

5. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 1, characterized in that: The specific formula for constructing the power constraint condition when the energy storage unit is in the main energy mode is: Where P t E represents the capacity provided by the energy storage unit in the main energy market at time t; e rated Indicates the rated capacity of the energy storage unit; η dc Indicates the energy storage discharge efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

6. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 1, characterized in that: The specific formula for constructing the power constraint condition when the energy storage unit is in frequency modulation mode is: Where P t F represents the capacity provided by the energy storage unit in the frequency regulation market at time t; e rated Indicates the rated capacity of the energy storage unit; η dc Indicates the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

7. The method for quoting a photovoltaic-storage combined power station in the electricity spot market according to claim 1, characterized in that: The specific formula for constructing the power constraint condition when the energy storage unit is in smooth mode is: When the energy storage unit smoothes the PV output fluctuations through charging: When the energy storage unit smoothes the PV output fluctuations by discharging: When the SOC value of the energy storage unit is large, you can freely choose to be in smoothing or main energy market operation mode: Where P t pe+ P represents the charging capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; t pe- It represents the discharge capacity provided by the energy storage unit of the photovoltaic-storage combined power station in smoothing mode; e rated Indicates the rated capacity of the energy storage unit; η dc Indicates the energy storage discharge efficiency; η ch Represents energy storage charging efficiency; P min and P max Respectively represent the minimum and maximum values ​​of the active power of the energy storage unit; Soc is a 0-1 variable to assist decision making; t,n It represents the state of charge of energy storage unit n at time t; Δt represents a discharge interval.

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