Photovoltaic power station cooperative frequency modulation system and control method thereof

Abstract

The invention relates to the technical field of photovoltaic cooperative frequency modulation, in particular to a photovoltaic power station cooperative frequency modulation system and a control method thereof. Comprising the following steps: establishing a photovoltaic state prediction model, and setting a plurality of regulation and control periods; according to the initial state parameter of the current regulation and control period and the photovoltaic state prediction model, setting a first-level regulation and control strategy in the current regulation and control period; a control signal is generated according to the first-level regulation and control strategy, and working parameters of the first energy storage module and the second energy storage module are set according to the control signal; by additionally arranging the first energy storage module and the second energy storage module, the high-frequency power change and the low-frequency power change of the power grid side are compensated in real time. And by establishing a photovoltaic state prediction model, each non-deterministic parameter (such as parameters of temperature, illumination radiation and the like) of the photovoltaic power station is predicted, and a regulation and control strategy is generated through rolling optimization of an objective function and constraint conditions, so that the frequency disturbance to a power grid is reduced, and the operation stability of the photovoltaic power station is improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic coordinated frequency modulation, and in particular to a photovoltaic power station coordinated frequency modulation system and a control method thereof. Background Art

[0002] Faced with the development trend of the power system dominated by renewable energy power generation, large-scale distributed photovoltaic power stations based on DCO are expected to become the main means of large-scale photovoltaic grid-connected power generation in the future.

[0003] However, incorporating large-scale photovoltaic power generation capacity into the power system will lead to a significant decrease in system inertia. Coupled with the volatility of photovoltaic output, it is difficult to cope with low-frequency / over-frequency events in the power system by relying solely on the frequency regulation method of synchronous generators, which may cause serious faults such as synchronous machine disconnection from the grid or even grid decoupling. Summary of the invention

[0004] The purpose of this application is: to solve the above technical problems, this application provides a photovoltaic power station collaborative frequency modulation system and its control method, aiming to reduce the frequency disturbance caused by photovoltaic power station power generation to the power grid and improve the frequency modulation efficiency.

[0005] In some embodiments of the present application, by adding a first energy storage module and a second energy storage module, high-frequency power changes and low-frequency power changes on the grid side are compensated in real time. And by establishing a photovoltaic state prediction model, various non-deterministic parameters of the photovoltaic power station (for example, parameters such as temperature and light radiation) are predicted, and a control strategy is generated through rolling optimization of the objective function and constraint conditions to reduce the frequency disturbance to the power grid and ensure that the photovoltaic power station is in the MPPT operating state. Improve the stability of the operation of the photovoltaic power station.

[0006] In some embodiments of the present application, a photovoltaic power station coordinated frequency modulation system control method is provided, including:

[0007] Establish a photovoltaic state prediction model and set multiple control cycles;

[0008] The primary control strategy within the current control cycle is set according to the initial state parameters of the current control cycle and the photovoltaic state prediction model;

[0009] Generate a control signal according to the primary regulation strategy, and set the working parameters of the first energy storage module and the second energy storage module according to the control signal;

[0010] The first energy storage module is used to compensate for high-frequency power changes on the grid side, and the second energy storage module is used to compensate for low-frequency power changes on the grid side.

[0011] In some embodiments of the present application, the primary control strategy in the current control cycle includes:

[0012] Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle;

[0013] According to the operation evaluation value a, the step length t of the current control cycle is set;

[0014] According to the step length t, a time interval sequence P of the current control cycle is established, P = (p1, p2...pn), where pi is the i-th time interval in the current control cycle based on the time sequence, and n is the number of time intervals;

[0015] Get the initial state parameters of the current control cycle;

[0016] S201: Select a time interval pi and generate initial state parameters of a node starting from the time interval pi;

[0017] S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model;

[0018] S203: solving according to initial state parameters, objective function and constraint conditions;

[0019] S204: Generate a sub-control plan within the time interval pi;

[0020] S206: If pi=pn, output all sub-control plans; if pi≠pn, set pi=pi+1, and iterate the above S201-S206;

[0021] Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

[0022] In some embodiments of the present application, when generating a primary control strategy of the current control cycle according to all sub-control plans, it includes:

[0023] Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval;

[0024] Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy;

[0025] Generate a feasibility evaluation value c of the initial control strategy;

[0026]

[0027] Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle;

[0028] Whether to generate a correction instruction is determined based on the feasibility evaluation value c, and a first-level control strategy is generated based on the determination result.

[0029] In some embodiments of the present application, when a primary control strategy is generated according to the judgment result, it includes:

[0030] Preset a first feasibility evaluation value threshold C1;

[0031] If c>C1, the initial control strategy is set as the first-level control strategy;

[0032] If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions;

[0033] And based on the correction results, the sub-control plan for each time interval is re-output.

[0034] In some embodiments of the present application, the generating of the operation evaluation value a in the previous regulation cycle includes:

[0035] Extract various evaluation indicators based on the operating parameters of the photovoltaic power station in the previous regulation cycle;

[0036] Generate an operation evaluation value a according to a preset evaluation model;

[0037]

[0038] Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; r is the number of evaluation indicators; βi is the influencing factor of the i-th evaluation indicator; fi is the reference value of the i-th evaluation indicator in the previous regulation cycle; f'i is the standard reference value of the i-th evaluation indicator.

[0039] In some embodiments of the present application, when the step length t of the current control cycle is set according to the operation evaluation value a, it includes:

[0040] Presetting a first operation evaluation value interval (A1, A2), a second operation evaluation value interval (A2, A3) and a third operation evaluation value interval (A3, A4);

[0041] If the operation evaluation value a is in the preset first operation evaluation value interval, the step duration t is set to the preset first step duration T1, that is, t=T1;

[0042] If the operation evaluation value a is in the preset second operation evaluation value interval, the step duration t is set to the preset second step duration T1, that is, t=T2;

[0043] If the operation evaluation value a is in the preset third operation evaluation value interval, the step time t is set to the preset third step time T1, that is, t=T3; and T1<T2<T3.

[0044] In some embodiments of the present application, a photovoltaic power station coordinated frequency modulation system is provided, including:

[0045] Central control unit, used to establish a photovoltaic system status prediction model;

[0046] An energy storage frequency modulation unit, comprising a first energy storage module and a second energy storage module;

[0047] The first energy storage module is used to compensate for high-frequency power changes on the grid side, and the second energy storage module is used to compensate for low-frequency power changes on the grid side;

[0048] Monitoring unit, used to collect real-time parameters of various status indicators;

[0049] The central control unit comprises:

[0050] The first processing module is used to establish a photovoltaic state prediction model and set multiple control cycles;

[0051] The second processing module is used to set the primary control strategy in the current control cycle according to the initial state parameters of the current control cycle and the photovoltaic state prediction model;

[0052] The first control module is used to generate a control signal according to the primary control strategy and set the working parameters of the first energy storage module and the second energy storage module according to the control signal.

[0053] In some embodiments of the present application, the second processing module is further used to:

[0054] Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle;

[0055] According to the operation evaluation value a, the step length t of the current control cycle is set;

[0056] According to the step length t, a time interval sequence P of the current control cycle is established, P = (p1, p2...pn), where pi is the i-th time interval in the current control cycle based on the time sequence, and n is the number of time intervals;

[0057] Get the initial state parameters of the current control cycle;

[0058] S201: Select a time interval pi and generate initial state parameters of a node starting from the time interval pi;

[0059] S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model;

[0060] S203: solving according to initial state parameters, objective function and constraint conditions;

[0061] S204: Generate a sub-control plan within the time interval pi;

[0062] S206: If pi=pn, output all sub-control plans; if pi≠pn, set pi=pi+1, and iterate the above S201-S206;

[0063] Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

[0064] In some embodiments of the present application, the second processing module is further used to:

[0065] Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval;

[0066] Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy;

[0067] Generate a feasibility evaluation value c of the initial control strategy;

[0068]

[0069] Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle;

[0070] Determine whether to generate a correction instruction based on the feasibility evaluation value c, and generate a first-level control strategy based on the determination result;

[0071] Preset a first feasibility evaluation value threshold C1;

[0072] If c>C1, the initial control strategy is set as the first-level control strategy;

[0073] If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions;

[0074] And based on the correction results, the sub-control plan for each time interval is re-output.

[0075] Compared with the prior art, the photovoltaic power station coordinated frequency modulation system and control method thereof in the embodiment of the present application have the following beneficial effects:

[0076] By adding the first energy storage module and the second energy storage module, the high-frequency power changes and low-frequency power changes on the grid side can be compensated in real time. By establishing a photovoltaic state prediction model, various non-deterministic parameters of the photovoltaic power station (for example, temperature and light radiation parameters) are predicted, and the control strategy is generated through rolling optimization of the objective function and constraint conditions to reduce the frequency disturbance to the grid and ensure that the photovoltaic power station is in the MPPT operation state. Improve the stability of the photovoltaic power station operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 It is a flow chart of a photovoltaic power station coordinated frequency modulation system control method in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0078] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0079] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0080] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0081] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0082] like Figure 1 As shown, a photovoltaic power station coordinated frequency modulation system control method according to a preferred embodiment of the present application includes:

[0083] S101: Establish a photovoltaic state prediction model and set multiple control cycles;

[0084] S102: setting a primary control strategy within the current control cycle according to the initial state parameters of the current control cycle and the photovoltaic state prediction model;

[0085] S103: generating a control signal according to the primary regulation strategy, and setting working parameters of the first energy storage module and the second energy storage module according to the control signal;

[0086] The first energy storage module is used to compensate for high-frequency power changes on the grid side, and the second energy storage module is used to compensate for low-frequency power changes on the grid side.

[0087] Specifically, when setting the primary control strategy within the current control cycle, it includes:

[0088] Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle;

[0089] According to the operation evaluation value a, the step length t of the current control cycle is set;

[0090] According to the step length t, a time interval sequence P of the current control cycle is established, P = (p1, p2...pn), where pi is the i-th time interval in the current control cycle based on the time sequence, and n is the number of time intervals;

[0091] Get the initial state parameters of the current control cycle;

[0092] S201: Select a time interval pi and generate initial state parameters of a node starting from the time interval pi;

[0093] S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model;

[0094] S203: solving according to initial state parameters, objective function and constraint conditions;

[0095] S204: Generate a sub-control plan within the time interval pi;

[0096] S206: If pi=pn, output all sub-control plans; if pi≠pn, set pi=pi+1, and iterate the above S201-S206;

[0097] Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

[0098] Specifically, the first energy storage module is preferably a supercapacitor energy storage module, which is responsible for compensating for high-frequency power changes on the grid side, and the second energy storage module is preferably a battery energy storage module, which is responsible for compensating for low-frequency power changes on the grid side.

[0099] Specifically, the objective function can be constructed according to the optimization goal of the photovoltaic power station, including but not limited to the cost function, and the constraint conditions can be constructed according to the operation requirements of the photovoltaic power station, including but not limited to: energy storage device operation constraints, energy storage device reference power and SOC constraints and photovoltaic operation constraints, etc.

[0100] Specifically, according to the MPC algorithm, the initial state parameters are obtained, and the various non-deterministic parameters of the photovoltaic power station (for example, temperature and light radiation parameters) are predicted. Then, the control strategy is generated through rolling optimization of the objective function and constraint conditions to reduce the frequency disturbance to the power grid.

[0101] Specifically, the status parameters include, but are not limited to, light intensity, temperature, light shielding range, grid frequency, photovoltaic voltage and grid-connected voltage parameters.

[0102] Specifically, signals are sent according to the first-level control strategy so that the first energy storage module can compensate for the high-frequency power changes on the grid side, and the second energy storage module can compensate for the low-frequency power changes on the grid side, while ensuring that the photovoltaic system maintains the MPPT operating state.

[0103] In a preferred embodiment of the present application, when generating a primary control strategy for the current control cycle according to all sub-control plans, it includes:

[0104] Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval;

[0105] Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy;

[0106] Generate a feasibility evaluation value c of the initial control strategy;

[0107]

[0108] Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle;

[0109] Whether to generate a correction instruction is determined based on the feasibility evaluation value c, and a first-level control strategy is generated based on the determination result.

[0110] Specifically, a single sub-control plan includes compensation parameters of the first energy storage module and compensation parameters of the second energy storage module.

[0111] Specifically, the fusion evaluation value refers to the difference in working parameters of the same energy storage module between two adjacent sub-control plans. The smaller the difference, the greater the fusion evaluation value.

[0112] Specifically, the higher the feasibility evaluation value is, the lower the possibility of sudden changes in the working parameters of the first energy storage module and the second energy storage module in the current primary control strategy within the control cycle, and the stronger its ability to reduce grid frequency disturbances is.

[0113] Specifically, when generating a first-level regulatory strategy based on the judgment results, it includes:

[0114] Preset a first feasibility evaluation value threshold C1;

[0115] If c>C1, the initial control strategy is set as the first-level control strategy;

[0116] If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions;

[0117] And based on the correction results, the sub-control plan for each time interval is re-output.

[0118] Specifically, through cyclic iteration, the primary control strategy can more accurately reduce the frequency disturbance of photovoltaic power generation to the power grid, and improve the operating stability and efficiency of photovoltaic power stations.

[0119] 5. The photovoltaic power station coordinated frequency modulation system control method according to claim 3, characterized in that when generating the operation evaluation value a in the previous regulation cycle, it includes:

[0120] Extract various evaluation indicators based on the operating parameters of the photovoltaic power station in the previous regulation cycle;

[0121] Generate an operation evaluation value a according to a preset evaluation model;

[0122]

[0123] Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; r is the number of evaluation indicators; βi is the influencing factor of the i-th evaluation indicator; fi is the reference value of the i-th evaluation indicator in the previous regulation cycle; f'i is the standard reference value of the i-th evaluation indicator.

[0124] Specifically, the evaluation indicators include but are not limited to the compensation efficiency for high-frequency power changes, the compensation efficiency for low-frequency power changes, the regulation cost, the photovoltaic operation efficiency, etc.

[0125] Specifically, the higher the operation evaluation value, the smaller the frequency disturbance in the previous regulation cycle, and the higher the operating efficiency of the photovoltaic power station.

[0126] Specifically, when the step length t of the current control cycle is set according to the operation evaluation value a, it includes:

[0127] Presetting a first operation evaluation value interval (A1, A2), a second operation evaluation value interval (A2, A3) and a third operation evaluation value interval (A3, A4);

[0128] If the operation evaluation value a is in the preset first operation evaluation value interval, the step duration t is set to the preset first step duration T1, that is, t=T1;

[0129] If the operation evaluation value a is in the preset second operation evaluation value interval, the step duration t is set to the preset second step duration T1, that is, t=T2;

[0130] If the operation evaluation value a is in the preset third operation evaluation value interval, the step time t is set to the preset third step time T1, that is, t=T3; and T1<T2<T3.

[0131] Specifically, the above embodiment reduces the number of optimization iterations in a single control cycle and the amount of calculation required to be sought, thereby improving the efficiency of building the control strategy, by dynamically adjusting the step duration while ensuring the frequency regulation efficiency of the photovoltaic power station.

[0132] Based on another preferred embodiment of a photovoltaic power station coordinated frequency modulation system control method in any of the above preferred embodiments, this preferred embodiment provides a photovoltaic power station coordinated frequency modulation system, including:

[0133] Central control unit, used to establish a photovoltaic system status prediction model;

[0134] An energy storage frequency modulation unit, comprising a first energy storage module and a second energy storage module;

[0135] The first energy storage module is used to compensate for the high-frequency power changes on the grid side, and the second energy storage module is used to compensate for the low-frequency power changes on the grid side;

[0136] Monitoring unit, used to collect real-time parameters of various status indicators;

[0137] The central control unit includes:

[0138] The first processing module is used to establish a photovoltaic state prediction model and set multiple control cycles;

[0139] The second processing module is used to set the primary control strategy in the current control cycle according to the initial state parameters of the current control cycle and the photovoltaic state prediction model;

[0140] The first control module is used to generate a control signal according to the primary control strategy and set the working parameters of the first energy storage module and the second energy storage module according to the control signal.

[0141] Specifically, the second processing module is further used for:

[0142] Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle;

[0143] According to the operation evaluation value a, the step length t of the current control cycle is set;

[0144] According to the step length t, a time interval sequence P of the current control cycle is established, P = (p1, p2...pn), where pi is the i-th time interval in the current control cycle based on the time sequence, and n is the number of time intervals;

[0145] Get the initial state parameters of the current control cycle;

[0146] S201: Select a time interval pi and generate initial state parameters of a node starting from the time interval pi;

[0147] S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model;

[0148] S203: solving according to initial state parameters, objective function and constraint conditions;

[0149] S204: Generate a sub-control plan within the time interval pi;

[0150] S206: If pi=pn, output all sub-control plans; if pi≠pn, set pi=pi+1, and iterate the above S201-S206;

[0151] Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

[0152] Specifically, the second processing module is further used for:

[0153] Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval;

[0154] Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy;

[0155] Generate a feasibility evaluation value c of the initial control strategy;

[0156]

[0157] Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle;

[0158] Determine whether to generate a correction instruction based on the feasibility evaluation value c, and generate a first-level control strategy based on the determination result;

[0159] Preset a first feasibility evaluation value threshold C1;

[0160] If c>C1, the initial control strategy is set as the first-level control strategy;

[0161] If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions;

[0162] And based on the correction results, the sub-control plan for each time interval is re-output.

[0163] According to the first concept of the present application, by adding a first energy storage module and a second energy storage module, high-frequency power changes and low-frequency power changes on the grid side are compensated in real time. And by establishing a photovoltaic state prediction model, various non-deterministic parameters of the photovoltaic power station (for example, parameters such as temperature and light radiation) are predicted, and the control strategy is generated through rolling optimization of the objective function and constraint conditions to reduce the frequency disturbance to the power grid and ensure that the photovoltaic power station is in the MPPT operating state. Improve the stability of the operation of the photovoltaic power station.

[0164] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. A photovoltaic power station coordinated frequency modulation system control method, characterized in that: include: Establish a photovoltaic state prediction model and set multiple control cycles; The primary control strategy within the current control cycle is set according to the initial state parameters of the current control cycle and the photovoltaic state prediction model; Generate a control signal according to the primary regulation strategy, and set the working parameters of the first energy storage module and the second energy storage module according to the control signal; The first energy storage module is used to compensate for high-frequency power changes on the grid side, and the second energy storage module is used to compensate for low-frequency power changes on the grid side.

2. The photovoltaic power station coordinated frequency modulation system control method according to claim 1, characterized in that: The primary control strategy within the current control cycle includes: Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle; According to the operation evaluation value a, the step length t of the current control cycle is set; According to the step-by-step duration t, the time interval sequence P of the current control cycle is established, P = (p1, p2...p n ), where p i is the i-th time interval in the current regulation cycle based on the time sequence, and n is the number of time intervals; Get the initial state parameters of the current control cycle; S201: Select time interval p i， Generate time interval p i Initial state parameters of the start node; S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model; S203: solving according to initial state parameters, objective function and constraint conditions; S204: Generate a sub-control plan within the time interval pi; S206: If p i =p n , output all sub-control plans; if p i ≠p n , set p i =p i+1， Iterate the above S201-S206; Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

3. The photovoltaic power station coordinated frequency modulation system control method according to claim 2, characterized in that: When generating the primary control strategy of the current control cycle based on all sub-control plans, it includes: Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval; Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy; Generate a feasibility evaluation value c of the initial control strategy; Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle; Whether to generate a correction instruction is determined based on the feasibility evaluation value c, and a first-level control strategy is generated based on the determination result.

4. The photovoltaic power station coordinated frequency modulation system control method according to claim 3, characterized in that: When generating a primary control strategy based on the judgment results, it includes: Preset a first feasibility evaluation value threshold C1; If c>C1, the initial control strategy is set as the first-level control strategy; If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions; And based on the correction results, the sub-control plan for each time interval is re-output.

5. The photovoltaic power station coordinated frequency modulation system control method according to claim 3, characterized in that: The generating of the operation evaluation value a in the previous control cycle includes: Extract various evaluation indicators based on the operating parameters of the photovoltaic power station in the previous regulation cycle; Generate an operation evaluation value a according to a preset evaluation model; Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; r is the number of evaluation indicators; βi is the influencing factor of the i-th evaluation indicator; fi is the reference value of the i-th evaluation indicator in the previous regulation cycle; f'i is the standard reference value of the i-th evaluation indicator.

6. The photovoltaic power station coordinated frequency modulation system control method according to claim 5, characterized in that: When the step-by-step duration t of the current control cycle is set according to the operation evaluation value a, it includes: Presetting a first operation evaluation value interval (A1, A2), a second operation evaluation value interval (A2, A3) and a third operation evaluation value interval (A3, A4); If the operation evaluation value a is in the preset first operation evaluation value interval, the step duration t is set to the preset first step duration T1, that is, t=T1; If the operation evaluation value a is in the preset second operation evaluation value interval, the step duration t is set to the preset second step duration T1, that is, t=T2; If the operation evaluation value a is in the preset third operation evaluation value interval, the step time t is set to the preset third step time T1, that is, t=T3; and T1<T2<T3.

7. A photovoltaic power station coordinated frequency modulation system, using the photovoltaic power station coordinated frequency modulation system control method according to any one of claims 1 to 6, characterized in that: include: Central control unit, used to establish a photovoltaic system status prediction model; An energy storage frequency modulation unit, comprising a first energy storage module and a second energy storage module; The first energy storage module is used to compensate for high-frequency power changes on the grid side, and the second energy storage module is used to compensate for low-frequency power changes on the grid side; Monitoring unit, used to collect real-time parameters of various status indicators; The central control unit comprises: The first processing module is used to establish a photovoltaic state prediction model and set multiple control cycles; The second processing module is used to set the primary control strategy in the current control cycle according to the initial state parameters of the current control cycle and the photovoltaic state prediction model; The first control module is used to generate a control signal according to the primary regulation strategy, and set the working parameters of the first energy storage module and the second energy storage module according to the control signal.

8. The photovoltaic power station coordinated frequency modulation system according to claim 7, characterized in that: The second processing module is also used for: Obtaining the operating parameters of the photovoltaic power station in the previous regulation cycle, and generating the operating evaluation value a in the previous regulation cycle; According to the operation evaluation value a, the step length t of the current control cycle is set; According to the step length t, a time interval sequence P of the current control cycle is established, P = (p1, p2...pn), where pi is the i-th time interval in the current control cycle based on the time sequence, and n is the number of time intervals; Get the initial state parameters of the current control cycle; S201: Select a time interval pi and generate initial state parameters of a node starting from the time interval pi; S202: Generate an objective function and constraint conditions according to a photovoltaic state prediction model; S203: solving according to initial state parameters, objective function and constraint conditions; S204: Generate a sub-control plan within the time interval pi; S206: If pi=pn, output all sub-control plans; if pi≠pn, set pi=pi+1, and iterate the above S201-S206; Obtain all sub-control plans and generate the primary control strategy for the current control cycle based on all sub-control plans.

9. The photovoltaic power station coordinated frequency modulation system according to claim 8, characterized in that: The second processing module is also used for: Establish a sub-control plan sequence B, B = (b1, b2...bn), where bi is the control plan for the i-th time interval; Based on the time sequence, all sub-control plans are integrated to generate the initial control strategy; Generate a feasibility evaluation value c of the initial control strategy; Among them, e1 is the preset first weight coefficient, e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; α is the compensation coefficient set based on the operation evaluation value a in the previous control cycle; di is the fusion evaluation value of the sub-control plan between the i-th time interval and the i+1-th time interval; a is the operation evaluation value a in the previous control cycle; Determine whether to generate a correction instruction based on the feasibility evaluation value c, and generate a first-level control strategy based on the determination result; Preset a first feasibility evaluation value threshold C1; If c>C1, the initial control strategy is set as the first-level control strategy; If c≤C1, a correction instruction is generated, and the photovoltaic state prediction model in the current regulation cycle is corrected according to the correction instruction to generate the objective function and constraint conditions; And based on the correction results, the sub-control plan for each time interval is re-output.

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