Power grid optimization scheduling method and device of offshore wind power grid-connected system, and medium

Abstract

The invention discloses a power grid optimization scheduling method and device for an offshore wind power grid-connected system and a medium. The method comprises the steps of determining a plurality of regulation and control state conversion time periods of the system based on typhoon time-varying feature information; in any regulation and control state conversion time period, determining target system operation information and executing corresponding system operation; constructing a system frequency response model and a frequency safety constraint formula; constructing a generator set resource cost control model and a first constraint formula; constructing a system load shedding response model and a second constraint formula; and optimizing a target model constructed based on the generator set resource cost control model and the system frequency response model by using a target constraint formula constructed by the first constraint formula and the second constraint formula, and solving the optimized target model by using a Benders decoupling method. The regulation and control state conversion time of the system is predicted based on the typhoon time-varying characteristics, the system operation is adjusted, frequency, load shedding capacity and other constraints are performed on the offshore wind power grid-connected system, and the operation safety of the system is guaranteed.

Description

Technical Field

[0001] The present application relates to, but is not limited to, the technical field of offshore wind power grid-connected system dispatching, and in particular to a grid optimization dispatching method, device, and medium for an offshore wind power grid-connected system. Background Art

[0002] Offshore wind power plays an important role in the process of low-carbon energy transformation. The operation of offshore wind farms is deeply affected by typhoon disasters. Before the typhoon lands, excessively high wind speeds will not only cause huge pressure on the structure of offshore wind turbines, but also bring large output power changes to the offshore wind power grid-connected system. After the typhoon lands, the transmission lines may be damaged by the typhoon. Typhoon disasters affect the power balance of offshore wind power grid-connected systems, thereby threatening the frequency security of the system. The existing method is to achieve flexible scheduling through active unit combination schemes to actively manage the power generation side, battery energy storage system and demand side resources. However, this method has not yet solved the problem of uncertainty in wind turbines and stage duration under typhoon disasters, and thus cannot guarantee the operating safety of each device in the offshore wind power grid-connected system, as well as the system frequency security. Summary of the invention

[0003] The embodiments of the present application provide a grid optimization scheduling method, device, and medium for an offshore wind power grid-connected system, which can ensure the operational safety of each module in the offshore wind power grid-connected system and the system frequency safety when a typhoon comes.

[0004] In a first aspect, an embodiment of the present application provides a power grid optimization scheduling method for an offshore wind power grid-connected system, the method being applied to an offshore wind power grid-connected system, the method comprising:

[0005] Determine the typhoon time-varying characteristic information, wherein the typhoon time-varying characteristic information includes the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance, gradient wind speed and wind power corresponding to the current timestamp, wherein the reference distance is used to indicate the distance between the offshore wind power grid-connected system and the typhoon center point, and the wind power is the maximum output power of the wind turbines of the offshore wind power grid-connected system under different wind speed conditions;

[0006] Determine multiple control state transition time periods of the offshore wind power grid-connected system based on the typhoon translation speed, the typhoon forward direction information, the typhoon intensity information, the reference distance and the gradient wind speed and the wind power corresponding to the current timestamp, each of the state transition time periods uniquely corresponding to a system state;

[0007] In the case where the current timestamp is in any one of the multiple control state conversion time periods, determine the corresponding target system state, determine the target system operation information from a preset relationship mapping table based on the target system state, and perform the system operation corresponding to the target system operation information, wherein the relationship mapping table is used to indicate the mapping relationship between the system state and the system operation information, and the system operation information represents the controllable resources and scheduling operation information of the offshore wind power grid-connected system;

[0008] A system frequency response model is constructed based on the system comprehensive inertia of the offshore wind power grid-connected system, the frequency modulation increment of the energy storage output, the system frequency deviation and the system damping parameter, and a target frequency safety constraint type frequency safety linearization constraint type frequency safety constraint type is constructed based on the system frequency response model and a preset system safety frequency threshold;

[0009] A generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation identifier, generator set shutdown operation identifier, and generator set status information of the offshore wind power grid-connected system, and a first constraint formula is constructed based on a preset minimum startup time, a preset shutdown time, and a generator state constraint condition;

[0010] A system load shedding response model is constructed based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount of the offshore wind power grid-connected system, and a second constraint formula is constructed based on a preset energy storage capacity threshold, a load shedding increase threshold, and a load shedding decrease threshold;

[0011] Based on the target frequency safety constrained frequency safety linearization constrained frequency safety constrained optimization of the system frequency response model;

[0012] constructing a target constraint formula based on the first constraint formula and the second constraint formula, constructing a target model based on the generator set resource cost control model and the system load shedding response model, and optimizing the target model based on the target constraint formula;

[0013] The optimized target model is solved based on the distributed decoupling algorithm of multiple Benders cuts.

[0014] In some embodiments, the control state conversion time period includes a warning state time period, an emergency state time period, a repair state time period and a normal state time period. The offshore wind power grid-connected system includes a generator set, a transmission line and a load control module. The generator set, the transmission line and the load control module are respectively corresponding to reference operating parameters. Each corresponding reference operating parameter is used to indicate the operating parameters of the generator set, the transmission line and the load control module when the offshore wind power grid-connected system is in a normal state. When the current timestamp is in any one of the multiple control state conversion time periods, the corresponding target system state is determined, and the target system operation information is determined from a preset relationship mapping table based on the target system state, and the system operation corresponding to the target system operation information is executed, including:

[0015] In the case where the current timestamp is in the warning state time period, determining that the target system state corresponding to the warning state time period is the warning state, and obtaining the target system operation information corresponding to the warning state from the relationship mapping table, and pre-scheduling the generator set according to the corresponding target system operation information;

[0016] In the case where the current timestamp is in the emergency time period, determining that the target system state corresponding to the emergency time period is an emergency state, and obtaining the target system operation information corresponding to the emergency state from the relationship mapping table, and controlling the transmission line to output a preset emergency transmission capacity according to the corresponding target system operation information, and at the same time shedding the load on the load control module, wherein the emergency transmission capacity is greater than the normal transmission capacity of the transmission line;

[0017] In the case where the current timestamp is in the repair state time period, determining that the target system state corresponding to the repair state time period is a repair state, obtaining the target system operation information corresponding to the repair state from the relationship mapping table, and shedding the load of the load control module according to the corresponding target system operation information;

[0018] When the current timestamp is in the normal state time period, the target system state corresponding to the normal state time period is determined to be the normal state, and the target system operation information corresponding to the normal state is obtained from the relationship mapping table, and according to the corresponding target system operation information, the generator set, the transmission line and the load control module are respectively controlled based on the corresponding reference operation parameters.

[0019] In some embodiments, the gradient wind speed is calculated according to the following formula:

[0020]

[0021] in, is the gradient wind speed, is the proportionality factor, r ω is the reference distance, δ is the adjustment factor used to describe small changes in wind speed, is the distance between the wind farm and the typhoon center, t is the current timestamp, and ω is the current scene information;

[0022] The wind power is calculated according to the following formula:

[0023]

[0024] in, is the wind power, which is used to indicate the wind speed at time t. Under the maximum power point tracking output power of the wind turbine, V 启 V is the starting wind speed, which is used to indicate the minimum wind speed at which the wind turbine of the wind turbine generator set starts to generate electricity. 额 is the rated wind speed, which is used to indicate the wind speed at which the wind turbine of the wind turbine generator set reaches the maximum power output, V 停 is the shutdown wind speed, which is used to indicate the wind speed at which the wind turbine of the wind turbine set stops operating for protection of the equipment. 额 is the rated power output of the wind turbine of the wind turbine generator set, and τ is the rotor radius of the wind turbine generator set.

[0025] In some embodiments, a frequency safety constraint formula is constructed based on the system frequency response model and a preset system safety frequency threshold according to the following formula:

[0026]

[0027] Where Δf max is the preset system safety frequency threshold, f0 is the current frequency of the system, is the weight coefficient related to load change, which is used to measure the impact of power change caused by generator inertia on system frequency. is the power change of the lth load at time t and scenario ω, is the weight coefficient related to the system reserve power, which is used to quantify the contribution of frequency regulation reserve to system frequency stability. sys,t is the total reserve power of the system at time t, is the weight coefficient related to the system inertia, which is used to reflect the inhibitory effect of the system inertia on the frequency change. is the total inertia of the system at time t and scenario ω, is the weight coefficient related to system damping, which is used to indicate the ability to damp frequency oscillations. sys,tis the total damping coefficient of the system at time t, is a constant related to the system;

[0028] The frequency safety constraint formula is obtained by converting the following formula using a piecewise linearization method of convex optimization:

[0029]

[0030] in, is the frequency deviation at the lowest point of the system frequency in the ω scenario at time t, D sys is the system damping parameter, R sys is the frequency regulation reserve of the system, T g is the time constant of the speed regulator of the thermal power unit, F sys is the power generation ratio of the system, is the system comprehensive inertia, ξ is the damping ratio, which indicates the degree of system damping, ω n is the natural frequency of the system, t nadir is the time to reach the lowest frequency point;

[0031]

[0032]

[0033] Among them, ω d is the damped oscillation angular frequency, u g,t is the operating status of the generator set g at time t, is the maximum output power of generator set g, K g is the mechanical power gain factor of the thermal power unit, R g is the active power droop control coefficient of the thermal power unit, is the generator set, F g is the proportion of power generation by high-pressure boilers, R f is the droop control coefficient of the offshore wind farm, w is the offshore wind farm, For offshore wind farms, P f is the rated power of the offshore wind farm f, R s is the droop control coefficient of the energy storage device, P s is the output power of energy storage device s, s is a certain energy storage device, S is the battery energy storage system set, D g is the damping coefficient of the conventional generator set g.

[0034] In some embodiments, a generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation identifier, generator set shutdown operation identifier, and generator set status information of the offshore wind power grid-connected system, and is obtained according to the following formula:

[0035]

[0036] Wherein, f(x) is the objective function corresponding to the resource cost control model of the generator set, c 开,g is the startup cost of the generator set, c 关,g is the shutdown cost of the generator set, α g,t is the generator set start operation identifier, β g,t The shutdown operation mark of the generator set, c T is the cost coefficient vector, x is the decision variable vector, △t is the time change, is the time set, is a generator set, and t is the current timestamp.

[0037] In some embodiments, the first constraint formula includes a first sub-constraint formula, a second sub-constraint formula, a third sub-constraint formula and a fourth sub-constraint formula, and the first constraint formula is constructed based on a preset minimum startup cost, a preset downtime duration, and a generator state constraint condition, and is obtained according to the following formula:

[0038] The expression of the first sub-constraint is:

[0039]

[0040] The expression of the second sub-constraint is:

[0041]

[0042] The expression of the third sub-constraint is:

[0043]

[0044] The expression of the fourth sub-constraint is:

[0045]

[0046] in, is the shutdown state of the generator set at time t, α g,b is the starting state of the generator set at time b, β g,b is the shutdown state of the generator set at time b, u g,0 is the operating status of the generator set g at the initial time, UT g is the minimum start-up time of generator set g, DT g is the minimum shutdown time of the generator set g, UT r is the minimum start-up time of the generator set g in the initial state, DT r is the minimum shutdown time of generator set g in the initial state.

[0047] In some embodiments, a system load shedding response model is constructed based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount of the offshore wind power grid-connected system, and is obtained according to the following formula:

[0048]

[0049] Among them, q(y ω ) is the objective function corresponding to the system load shedding response model, α g is the fuel cost for power generation of the unit, is the power generation of generator g at time t under scenario ω, c LCOE is the energy storage charging and discharging cost, is the energy storage charging and discharging power, is the load shedding cost, c VOLL is the load shedding cost, is the load shedding amount, and t is the current timestamp.

[0050] In some embodiments, the second constraint is obtained according to the following formula:

[0051]

[0052] Among them, u g,t is the generator set status information, is the minimum power limit of the generator set g, p g,t is the actual power generation of generator set g at time t, is the maximum power limit of the generator set g, R g,t is the spare capacity of generator set g at time t, used to cope with load changes or failures, is the actual power generation of generator set g at time t under scenario ω, is the maximum power boost capability provided by the generator set g within the time interval Δt, u g,t-1 is the operating state of the generator set g at time t-1, SU g is the starting power slope of generator set g, α g,t is the starting state of the generator set g at time t, SD is the maximum power reduction capability provided by the generator set g within the time interval Δt. g is the shutdown power slope of generator set g, β g,t is the shutdown state of the generator set g at time t, ω represents different scenarios, is an arbitrary timestamp, is the switch state indicator variable of line ij at time t and scenario ω, is the active power flow of line ij at time t and scenario ω, B ij is the value of the admittance matrix of line ij, is the phase angle of node i at time t and scenario ω, is the phase angle of node j at time t and scenario ω, i and j are nodes in the line respectively, ij is the transmission line connecting nodes i and j, is the maximum active power of line ij, is the state indicator variable of the disturbance at time t and scenario ω, is the maximum power change of line ij after considering the disturbance, is the maximum active power of line ij under the preset condition k, e is the energy state of the energy storage device, is the charging power of energy storage device s at time t and scenario ω, is the maximum charging power of the energy storage device s, is the discharge power of energy storage device s at time t and scenario ω, is the maximum discharge power of the energy storage device s, ch is the charging process, and dc is the discharging process.

[0053] In a second aspect, an embodiment of the present application provides a control device, comprising at least one control processor and a memory for communicating with the at least one control processor; the memory stores instructions that can be executed by the at least one control processor, and the instructions are executed by the at least one control processor so that the at least one control processor can execute the grid optimization scheduling method for the offshore wind power grid-connected system as described in the first aspect.

[0054] In a third aspect, an embodiment of the present application further provides a computer-readable storage medium storing computer-executable instructions, wherein the computer-executable instructions are used to execute the grid optimization scheduling method for the offshore wind power grid-connected system as described in the first aspect.

[0055] The embodiment of the present application provides a grid optimization scheduling method, device, and medium for an offshore wind power grid-connected system, the method comprising: determining time-varying characteristic information of a typhoon, wherein the time-varying characteristic information of the typhoon comprises the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance, gradient wind speed, and wind power corresponding to a current timestamp, wherein the reference distance is used to indicate the distance between the offshore wind power grid-connected system and the typhoon center point, and the wind power is the maximum output power of the wind turbine group of the offshore wind power grid-connected system under different wind speed conditions; based on the typhoon translation speed, the typhoon forward direction information, the typhoon intensity information, the reference distance, the gradient wind speed, and the wind power corresponding to the current timestamp The method comprises the steps of: determining a plurality of control state transition time periods of the offshore wind power grid-connected system based on the wind speed and the wind power, each of the state transition time periods uniquely corresponding to a system state; determining a corresponding target system state when a current timestamp is in any one of the plurality of control state transition time periods, determining target system operation information from a preset relationship mapping table based on the target system state, and executing a system operation corresponding to the target system operation information, wherein the relationship mapping table is used to indicate a mapping relationship between a system state and system operation information, and the system operation information represents controllable resources and scheduling operation information of the offshore wind power grid-connected system; and determining a corresponding target system state when a current timestamp is in any one of the plurality of control state transition time periods. A system frequency response model is constructed based on the system comprehensive inertia of the grid system, the frequency regulation increment of the energy storage output, the system frequency deviation and the system damping parameter, and a target frequency safety constraint frequency safety linearization constraint frequency safety constraint is constructed based on the system frequency response model and the preset system safety frequency threshold; a generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation mark, generator set shutdown operation mark and generator set status information of the offshore wind power grid-connected system, and a first constraint is constructed based on the preset minimum startup time, the preset shutdown time and the generator state constraint condition; a fuel cost for generating electricity of the generator set of the offshore wind power grid-connected system is constructed. , energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount to build a system load shedding response model, and build a second constraint based on a preset energy storage capacity threshold, a load shedding increase threshold, and a load shedding decrease threshold; optimize the system frequency response model based on the target frequency safety constraint, the frequency safety linearization constraint, and the frequency safety constraint; build a target constraint based on the first constraint and the second constraint, build a target model based on the generator set resource cost control model and the system load shedding response model, and optimize the target model based on the target constraint; solve the optimized target model based on the distributed decoupling algorithm based on the multi-Benders cut.According to the solution provided in the embodiment of the present application, the control state transition of the offshore wind power grid-connected system is predicted and the system operation is adjusted based on the time-varying characteristic information of the typhoon, and the frequency constraint, load shedding constraint and operating cost constraint are performed on the offshore wind power grid-connected system after the switching state, thereby reducing the adverse effects on the offshore wind power grid-connected system before and after the arrival of the typhoon, thereby effectively ensuring the operating safety of each module in the system and the system frequency safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a flowchart of the steps of a grid optimization dispatching method for an offshore wind power grid-connected system provided by an embodiment of the present application;

[0057] Figure 2 is a flowchart of steps for an offshore wind power grid-connected system to perform different system operations in different system states provided by another embodiment of the present application;

[0058] Figure 3 It is a structural diagram of a control device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0059] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0060] It is understood that although the functional modules are divided in the device schematic diagram and the logical order is shown in the flow chart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flow chart. The terms "first", "second", etc. in the specification, claims or the above drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0061] Offshore wind power plays an important role in the process of low-carbon energy transformation. The operation of offshore wind farms is deeply affected by typhoon disasters. Before the typhoon lands, excessively high wind speeds will not only cause huge pressure on the structure of offshore wind turbines, but also bring large output power changes to the offshore wind power grid-connected system. After the typhoon lands, the transmission lines may be damaged by the typhoon. Typhoon disasters affect the power balance of offshore wind power grid-connected systems, thereby threatening the frequency security of the system. The existing method is to achieve flexible scheduling through active unit combination schemes to actively manage the power generation side, battery energy storage system and demand side resources. However, this method has not yet solved the problem of uncertainty in wind turbines and stage duration under typhoon disasters, and thus cannot guarantee the operating safety of each device in the offshore wind power grid-connected system, as well as the system frequency security.

[0062] To solve the above-mentioned problems, the embodiments of the present application provide a method, device, and medium for optimizing the dispatching of a power grid of an offshore wind power grid-connected system. The method comprises: determining time-varying characteristic information of a typhoon, wherein the time-varying characteristic information of the typhoon comprises the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance, gradient wind speed, and wind power corresponding to a current timestamp, wherein the reference distance is used to indicate the distance between the offshore wind power grid-connected system and the typhoon center point, and the wind power is the maximum output power of a wind turbine set of the offshore wind power grid-connected system under different wind speed conditions; based on the typhoon translation speed, the typhoon forward direction information, the typhoon intensity information, the reference distance, the gradient wind speed, and the wind power corresponding to the current timestamp The reference distance, the gradient wind speed and the wind power determine multiple control state transition time periods of the offshore wind power grid-connected system, each of the state transition time periods uniquely corresponding to a system state; when the current timestamp is in any one of the multiple control state transition time periods, determine the corresponding target system state, determine the target system operation information from a preset relationship mapping table based on the target system state, and execute the system operation corresponding to the target system operation information, wherein the relationship mapping table is used to indicate the mapping relationship between the system state and the system operation information, and the system operation information represents the controllable resources and scheduling operation information of the offshore wind power grid-connected system; based on the A system frequency response model is constructed based on the system comprehensive inertia of the offshore wind power grid-connected system, the frequency modulation increment of the energy storage output, the system frequency deviation and the system damping parameter, and a target frequency safety constraint type frequency safety linearization constraint type frequency safety constraint type is constructed based on the system frequency response model and the preset system safety frequency threshold; a generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation mark, generator set shutdown operation mark and generator set status information of the offshore wind power grid-connected system, and a first constraint type is constructed based on the preset minimum startup time, the preset shutdown time and the generator state constraint condition; ... A system load shedding response model is constructed based on material cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount, and a second constraint formula is constructed based on a preset energy storage capacity threshold, a load shedding increase threshold, and a load shedding decrease threshold; the system frequency response model is optimized based on the target frequency safety constraint formula, the frequency safety linearization constraint formula, and the frequency safety constraint formula; a target constraint formula is constructed based on the first constraint formula and the second constraint formula, a target model is constructed based on the generator set resource cost control model and the system load shedding response model, and the target model is optimized based on the target constraint formula; the optimized target model is solved based on the distributed decoupling algorithm based on the multi-Benders cut.According to the scheme provided in the embodiment of the present application, the control state conversion of the offshore wind power grid-connected system is predicted and the system operation is adjusted based on the typhoon time-varying characteristic information, and the frequency constraint, load shedding constraint and operation cost constraint are performed on the offshore wind power grid-connected system after the switching state, so as to reduce the adverse effects on the offshore wind power grid-connected system before and after the typhoon, thereby effectively ensuring the operation safety of each module in the system and the system frequency safety. The embodiment of the present application is further described below in conjunction with the accompanying drawings.

[0063] refer to Figure 1 , Figure 1 The present invention provides a method for optimizing the power grid scheduling of an offshore wind power grid-connected system, which is applied to the offshore wind power grid-connected system. The method includes but is not limited to the following steps:

[0064] Step S10, determining the typhoon time-varying characteristic information, the typhoon time-varying characteristic information includes the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance, gradient wind speed and wind power corresponding to the current timestamp, wherein the reference distance is used to indicate the distance between the offshore wind power grid-connected system and the typhoon center point;

[0065] Step S20, based on the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance and gradient wind speed corresponding to the current timestamp, multiple control state conversion time periods of the offshore wind power grid-connected system are determined, and each control state conversion time period uniquely corresponds to a system state.

[0066] It can be understood that this embodiment can effectively analyze the impact of the typhoon on the offshore wind power grid-connected system composed of offshore wind farms, transmission lines, transmission towers, generator sets, etc. before and after landing by calculating the typhoon translation speed, typhoon forward direction information (i.e. typhoon track characteristics), typhoon intensity information, reference distance and gradient wind speed (i.e. typhoon wind field characteristics) and other typhoon time-varying characteristic information corresponding to the current timestamp, thereby providing an effective data basis for the specific timestamp of the subsequent prediction system regulation conversion state.

[0067] It should be noted that the gradient wind speed is calculated according to the following formula:

[0068]

[0069] in, is the gradient wind speed, is the proportionality factor, r ω is the reference distance, δ is the adjustment factor used to describe small changes in wind speed, is the distance between the wind farm and the typhoon center, t is the current timestamp, and ω is the current scene information.

[0070] It should be noted that the typhoon's translation speed The typhoon forward direction information θ is calculated according to the following formula:

[0071]

[0072] Among them, a1, a2, and a3 are the correlation coefficients of the typhoon translation speed at time t and other times obtained based on historical data. is a random error, b1, b2, and b3 are the correlation coefficients between the typhoon's forward direction at time t and other times obtained based on historical data. is the site dimension at time t-1, is the relative strength at time t-1.

[0073] Step S30, when the current timestamp is in any one of the multiple control state conversion time periods, determine the corresponding target system state, determine the target system operation information from a preset relationship mapping table based on the target system state, and execute the system operation corresponding to the target system operation information, wherein the relationship mapping table is used to indicate the mapping relationship between the system state and the system operation information, and the system operation information represents the controllable resources and scheduling operation information of the offshore wind power grid-connected system.

[0074] Specifically, the control state conversion time period predicted based on the typhoon time-varying characteristic information includes a warning state time period, an emergency state time period, a repair state time period and a normal state time period. The offshore wind power grid-connected system includes a generator set, a transmission line and a load control module. The generator set, the transmission line and the load control module each correspond to a reference operating parameter. Each corresponding reference operating parameter is used to indicate the operating parameters of the generator set, the transmission line and the load control module when the offshore wind power grid-connected system is in a normal state. Figure 2 , Figure 1 Step S30 includes but is not limited to the following steps:

[0075] Step S31, when the current timestamp is in the warning state time period, determine that the target system state corresponding to the warning state time period is the warning state, obtain the target system operation information corresponding to the warning state from the relationship mapping table, and perform pre-scheduling and cutting of the generator set according to the corresponding target system operation information;

[0076] Step S32, when the current timestamp is in the emergency time period, determine that the target system state corresponding to the emergency time period is an emergency state, obtain target system operation information corresponding to the emergency state from the relationship mapping table, and control the transmission line to output a preset emergency transmission capacity according to the corresponding target system operation information, and cut the load of the load control module at the same time, wherein the emergency transmission capacity is greater than the normal transmission capacity of the transmission line;

[0077] Step S33, when the current timestamp is in the repair state time period, determine that the target system state corresponding to the repair state time period is the repair state, obtain the target system operation information corresponding to the repair state from the relationship mapping table, and cut the load of the load control module according to the corresponding target system operation information;

[0078] Step S34, when the current timestamp is in the normal state time period, determine that the target system state corresponding to the normal state time period is the normal state, and obtain the target system operation information corresponding to the normal state from the relationship mapping table, and according to the corresponding target system operation information, control the generator set, transmission line and load control module respectively based on the corresponding reference operation parameters.

[0079] It can be understood that, referring to the description of the above embodiment, when the typhoon is far away from the offshore wind power grid-connected system, the offshore wind power grid-connected system is in a normal state. Meet the N-1 safety standard; before the typhoon arrives, and when the current timestamp is in the warning state period, considering the adverse impact of the upcoming typhoon, adjust the system state to the warning state At this time, pre-dispatch action needs to be taken, without considering the N-1 working condition of the system, that is, pre-dispatch and cut the generator set; as the typhoon gets closer and closer to the offshore wind power grid-connected system, when a fault is judged, the system state is adjusted to an emergency state In this state, the transmission line is controlled to output the preset emergency transmission capacity, and the load control module is cut off at the same time, where the emergency transmission capacity is greater than the normal transmission capacity of the transmission line; when it is determined that the typhoon center is far away from the offshore wind power grid-connected system, the system state is adjusted to the repair state, the load control module is cut off, and the transmission line is reconstructed to minimize the system cost; after the system repair is completed, the system returns to normal. Due to the uncertainty of the typhoon path and impact, the system state during the scheduling period is expressed as That is to say, this embodiment predicts the timestamp of changing the system state of the offshore wind power grid-connected system by acquiring the time-varying characteristic information of the typhoon in real time, and performs different system operations accordingly based on the current system state of the offshore wind power grid-connected system, thereby ensuring the safe operation of the offshore wind power grid-connected system before and after the typhoon arrives.

[0080] Step S40, constructing a system frequency response model based on the system comprehensive inertia of the offshore wind power grid-connected system, the frequency modulation increment of the energy storage output, the system frequency deviation and the system damping parameter, and constructing a frequency safety constraint formula based on the system frequency response model and a preset system safety frequency threshold;

[0081] Specifically, based on the constructed system frequency response model, the frequency dynamic analysis calculation is performed to obtain the timestamp t when the system frequency lowest point occurs. nadir , according to the following formula:

[0082]

[0083]

[0084] Among them, ω d is the damping frequency, ω n is the natural frequency of the system, which is used to indicate the natural frequency of the system oscillation without damping, T g is the time constant of the speed regulator of the thermal power unit, D sys is the system damping parameter, R sys is the system active power droop control coefficient, is the system comprehensive inertia, F sys is the power generation ratio of the system, ξ is the damping ratio, which indicates the degree of system damping.

[0085] The system parameters involved in the above formula are obtained according to the following formula:

[0086]

[0087] Among them, ω d is the damped oscillation angular frequency, u g,t is the operating status of the generator set g at time t, is the maximum output power of generator set g, K g is the mechanical power gain factor of the thermal power unit, R g is the active power droop control coefficient of the thermal power unit, is the generator set, F g is the proportion of power generation by high-pressure boilers, R f is the droop control coefficient of the offshore wind farm, w is the offshore wind farm, For offshore wind farms, P f is the rated power of the offshore wind farm f, R s is the droop control coefficient of the energy storage device, P s is the output power of energy storage device s, s is a certain energy storage device, S is the battery energy storage system set, D g is the damping coefficient of the conventional generator set g.

[0088] The frequency safety constraint required by the offshore wind power grid-connected system is then established by the frequency analysis solution, that is, the frequency deviation at the lowest point of the system frequency should be less than the preset system safety frequency threshold:

[0089]

[0090] Where Δf max To preset the system safety frequency threshold, It is the frequency deviation of the lowest point of the system frequency.

[0091] Next, the equivalent aggregation model of the thermal power unit processing increment is calculated:

[0092]

[0093] in, K is the power change rate of generator g at time t under scenario ω. g is the mechanical power gain factor of the thermal power unit, F g is the proportion of power generation by high-pressure boilers, R g is the active power droop control coefficient of the thermal power unit, R s is the energy storage active power droop control coefficient, T s is the time constant of the energy storage speed regulator, Δf t ω is the change in system frequency at time t under scenario ω, is the power change rate of energy storage device s at time t under scenario ω, Δp s,t is the power change of energy storage device s at time t.

[0094] Based on the above timestamp expression of the system frequency minimum point and the equivalent aggregation model of the thermal power unit processing increment, the system frequency minimum point constraint is approximated by the piecewise linearization method, and the obtained frequency safety constraint is obtained according to the following formula:

[0095]

[0096] Where Δf max is the preset system safety frequency threshold, f0 is the current system frequency, is the weight coefficient related to load change, which is used to measure the impact of power change caused by generator inertia on system frequency. is the power change of the lth load at time t and scenario ω, is the weight coefficient related to the system reserve power, which is used to quantify the contribution of frequency regulation reserve to system frequency stability. sys,t is the total reserve power of the system at time t, is the weight coefficient related to the system inertia, which is used to reflect the inhibitory effect of the system inertia on the frequency change. is the total inertia of the system at time t and scenario ω, is the weight coefficient related to system damping, which is used to indicate the ability to damp frequency oscillations. sys,t is the total damping coefficient of the system at time t, is a constant related to the system.

[0097] It can be understood that the frequency safety constraint formula described above can effectively constrain the minimum value of the system frequency under abnormal conditions, thereby ensuring the safe operation of the offshore wind power grid-connected system.

[0098] The above frequency safety constraint formula is obtained by converting the following formula using the piecewise linearization method of convex optimization:

[0099]

[0100] in, is the frequency deviation between the time t and the lowest point of the system frequency in scenario ω, D sys is the system damping parameter, R sys is the frequency regulation reserve of the system, T g is the time constant of the speed regulator of the thermal power unit, F sys is the power generation ratio of the system,

[0101] is the system comprehensive inertia, ξ is the damping ratio, which indicates the degree of system damping, ω n is the natural frequency of the system, which is used to indicate the natural frequency of the system oscillation without damping, t nadir The timestamp of the lowest system frequency.

[0102]

[0103]

[0104] Among them, ω d is the damped oscillation angular frequency, u g,t is the operating status of the generator set g at time t, is the maximum output power of generator set g, K g is the mechanical power gain factor of the thermal power unit, R g is the active power droop control coefficient of the thermal power unit, g is the generator unit, is the generator set, F g is the proportion of power generation by high-pressure boilers, R f is the droop control coefficient of the offshore wind farm, w is the offshore wind farm, For offshore wind farms, P f is the rated power of the offshore wind farm f, R sis the droop control coefficient of the energy storage device, P s is the output power of energy storage device s, s is a certain energy storage device, S is the battery energy storage system set, D g is the damping coefficient of the conventional generator set g.

[0105] Step S50, constructing a generator set resource cost control model based on the generator set startup cost, generator set shutdown cost, generator set startup operation identifier, generator set shutdown operation identifier, and generator set status information of the offshore wind power grid-connected system, and constructing a first constraint formula based on a preset minimum startup time, a preset shutdown time, and a generator state constraint condition;

[0106] Step S60, constructing a system load shedding response model based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount of the offshore wind power grid-connected system, and constructing a second constraint formula based on a preset energy storage capacity threshold, a load shedding increase threshold, and a load shedding decrease threshold;

[0107] Step S70, optimizing the system frequency response model based on frequency safety constraints;

[0108] Step S80, constructing a target constraint formula based on the first constraint formula and the second constraint formula, constructing a target model based on the generator resource cost control model and the system load shedding response model, and optimizing the target model based on the target constraint formula;

[0109] Step S90, solving the optimized target model based on a distributed decoupling algorithm of multiple Benders cuts.

[0110] It should be noted that the generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation mark, generator set shutdown operation mark, and generator set status information of the offshore wind power grid-connected system, and is obtained according to the following formula:

[0111]

[0112] Among them, f(x) is the objective function corresponding to the resource cost control model of the generator set, that is, the objective function corresponding to the first stage optimization, c 开,g is the startup cost of the generator set, c 关,g is the shutdown cost of the generator set, α g,t is the generator set start operation mark, β g,t The generator set shutdown operation mark, c T is the cost coefficient vector, x is the decision variable vector, △t is the time change, is the time set, i.e., all the time periods considered, is the generator set, and t is the current timestamp.

[0113] It should be noted that the first constraint formula includes a first sub-constraint formula, a second sub-constraint formula, a third sub-constraint formula and a fourth sub-constraint formula. The first constraint formula is constructed based on the preset minimum startup cost, the preset downtime duration, and the generator state constraint condition, and is obtained according to the following formula:

[0114] The expression of the first sub-constraint is:

[0115]

[0116] The expression of the second sub-constraint is:

[0117]

[0118] The expression of the third sub-constraint is:

[0119]

[0120] The expression of the fourth sub-constraint is:

[0121]

[0122] in, is the shutdown state of generator set g at time t, α g,b is the starting state of generator set g at time b, β g,b is the shutdown state of generator set g at time b, u g,0 is the operating status of the generator set g at the initial time, UT g is the minimum start-up time of generator set g, DT g is the minimum shutdown time of the generator set g, UT r is the minimum start-up time of the generator set g in the initial state, DT r is the minimum shutdown time of generator set g in the initial state.

[0123] It can be understood that the above-mentioned first constraint formula can constrain various parameters in the resource cost control model of the generator set, such as realizing the restriction of the operating state conversion of the generator and the minimum startup cost, downtime duration and the initial state constraint of the generator, thereby ensuring that the offshore wind power grid-connected system can control the safety of the operation of the generator set and the demand-side resources and minimize the operating cost under abnormal conditions.

[0124] It should be noted that the load shedding response model of the system is constructed based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost and load shedding amount of the offshore wind power grid-connected system, which is obtained according to the following formula:

[0125]

[0126] This formula is the objective function of the second stage optimization, where q(y ω ) is the objective function corresponding to the system load shedding response model, α g is the fuel cost for generating electricity of the unit, is the power generation of generator g at time t under scenario ω, c LCOE is the energy storage charging and discharging cost, is the energy storage charging and discharging power, is the load shedding cost, c VOLL is the load shedding cost, is the load shedding amount, and t is the current timestamp.

[0127] It should be noted that the second constraint is obtained according to the following formula:

[0128]

[0129] Among them, u g,t It is the status information of the generator set. is the minimum power limit of the generator set g, p g,t is the actual power generation of generator set g at time t, is the maximum power limit of the generator set g, R g,t is the spare capacity of generator set g at time t, used to cope with load changes or failures, is the actual power generation of generator set g at time t under scenario ω, is the maximum power boost capability provided by the generator set g within the time interval Δt, u g,t-1 is the operating state of the generator set g at time t-1, SU g is the starting power slope of generator set g, α g,t is the starting state of the generator set g at time t, SD is the maximum power reduction capability provided by the generator set g within the time interval Δt. g is the shutdown power slope of generator set g, β g,t is the shutdown state of the generator set g at time t, ω represents different scenarios, is an arbitrary timestamp, is the switch state indicator variable of line ij at time t and scenario ω, is the active power flow of line ij at time t and scenario ω, B ij is the value of the admittance matrix of line ij, is the phase angle of node i at time t and scenario ω, is the phase angle of node j at time t and scenario ω, i and j are nodes in the line respectively, ij is the transmission line connecting nodes i and j, is the maximum active power of line ij, is the state indicator variable of the disturbance at time t and scenario ω, is the maximum power change of line ij after considering the disturbance, is the maximum active power of line ij under the preset condition k, e is the energy state of the energy storage device, is the charging power of energy storage device s at time t and scenario ω, is the maximum charging power of the energy storage device s, is the discharge power of energy storage device s at time t and scenario ω, is the maximum discharge power of the energy storage device s, s is the energy storage device, ch is the charging process, and dc is the discharging process.

[0130] It can be understood that the above second constraint formula can constrain various parameters in the system load shedding response model, such as realizing the capacity limit of energy storage and the limit of the increase and decrease of the total load shedding, thereby reducing the load shedding value of the system in emergency and repair states.

[0131] It should be noted that the target constraint formula is constructed based on the first constraint formula and the second constraint formula. The target constraint formula reflects the coupling variables between the decisions of the first stage (i.e., the optimization of the resource cost control model of the generator set corresponding to the first constraint formula) and the second stage (i.e., the optimization of the system load shedding response model corresponding to the second constraint formula). The nonlinear pursuit problem is then converted into a linear pursuit problem. Then, the converted linear pursuit problem is solved based on the distributed decoupling algorithm of multiple Benders cuts, that is, the target model is constructed based on the resource cost control model of the generator set and the system load shedding response model, and the target model is optimized based on the target constraint formula. The optimized target model is solved based on the distributed decoupling algorithm of multiple Benders cuts, so that the operation safety of each module in the offshore wind power grid-connected system and the system frequency safety can be guaranteed when a typhoon comes.

[0132] like Figure 3 As shown, Figure 3 : is a structural diagram of a control device provided by an embodiment of the present application. The present invention also provides a control device 300, including:

[0133] The processor 310 may be implemented by a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application;

[0134] The memory 320 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 320 can store an operating system and other application programs. When the technical solution provided in the embodiment of this specification is implemented by software or firmware, the relevant program code is stored in the memory 320, and the processor 310 calls and executes the power grid optimization scheduling method of the offshore wind power grid-connected system of the embodiment of this application;

[0135] Input / output interface 330, used to implement information input and output;

[0136] Communication interface 340, used to realize communication interaction between the apparatus and other devices, which can be realized by wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.);

[0137] bus 350 , which transmits information between the various components of the device (e.g., processor 310 , memory 320 , input / output interface 330 , and communication interface 340 );

[0138] The processor 310 , the memory 320 , the input / output interface 330 and the communication interface 340 are connected to each other in communication within the device via the bus 350 .

[0139] In addition, an embodiment of the present application further provides an electronic device, including the control device 300 of the above embodiment.

[0140] In addition, an embodiment of the present application further provides a storage medium, which is a computer-readable storage medium and stores a computer program. When the computer program is executed by a processor, the above-mentioned grid optimization scheduling method of the offshore wind power grid-connected system is implemented.

[0141] As a non-transient computer-readable storage medium, the memory can be used to store non-transient software programs and non-transient computer executable programs. In addition, the memory may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage devices. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned networks include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and are implemented to be located in one place, or may also be distributed to multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0142] It will be appreciated by those skilled in the art that all or some of the steps and systems in the disclosed method above may be implemented as software, firmware, hardware and appropriate combinations thereof. Some physical components or all physical components may be implemented as software executed by a processor, such as a central processing unit, a digital signal processor or a microprocessor, or may be implemented as hardware, or may be implemented as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or a non-transitory medium) and a communication medium (or a temporary medium). As known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules or other data). Computer storage media include, but are not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices, or any other medium that may be used to store desired information and may be accessed by a computer. Furthermore, it is well known to those skilled in the art that communication media typically include computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0143] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above-mentioned implementation mode. Technical personnel familiar with the field can also make various equivalent deformations or substitutions under the shared conditions without violating the spirit of the present invention. These equivalent deformations or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A method for optimizing the grid scheduling of an offshore wind power grid-connected system, characterized in that: Applied to an offshore wind power grid-connected system, the method comprises: Determine the typhoon time-varying characteristic information, wherein the typhoon time-varying characteristic information includes the typhoon translation speed, typhoon forward direction information, typhoon intensity information, reference distance, gradient wind speed and wind power corresponding to the current timestamp, wherein the reference distance is used to indicate the distance between the offshore wind power grid-connected system and the typhoon center point, and the wind power is the maximum output power of the wind turbines of the offshore wind power grid-connected system under different wind speed conditions; Determine multiple control state transition time periods of the offshore wind power grid-connected system based on the typhoon translation speed, the typhoon forward direction information, the typhoon intensity information, the reference distance, the gradient wind speed and the wind power corresponding to the current timestamp, each of the state transition time periods uniquely corresponding to a system state; In the case where the current timestamp is in any one of the multiple control state conversion time periods, determine the corresponding target system state, determine the target system operation information from a preset relationship mapping table based on the target system state, and perform the system operation corresponding to the target system operation information, wherein the relationship mapping table is used to indicate the mapping relationship between the system state and the system operation information, and the system operation information represents the controllable resources and scheduling operation information of the offshore wind power grid-connected system; A system frequency response model is constructed based on the system comprehensive inertia of the offshore wind power grid-connected system, the frequency modulation increment of the energy storage output, the system frequency deviation and the system damping parameter, and a frequency safety constraint formula is constructed based on the system frequency response model and a preset system safety frequency threshold; A generator set resource cost control model is constructed based on the generator set startup cost, generator set shutdown cost, generator set startup operation identifier, generator set shutdown operation identifier, and generator set status information of the offshore wind power grid-connected system, and a first constraint formula is constructed based on a preset minimum startup time, a preset shutdown time, and a generator state constraint condition; A system load shedding response model is constructed based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount of the offshore wind power grid-connected system, and a second constraint formula is constructed based on a preset energy storage capacity threshold, a load shedding increase threshold, and a load shedding decrease threshold; Optimizing the system frequency response model based on the frequency safety constraint; constructing a target constraint formula based on the first constraint formula and the second constraint formula, constructing a target model based on the generator set resource cost control model and the system load shedding response model, and optimizing the target model based on the target constraint formula; The optimized target model is solved based on the distributed decoupling algorithm of multiple Benders cuts.

2. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 1, characterized in that: The control state conversion time period includes a warning state time period, an emergency state time period, a repair state time period and a normal state time period. The offshore wind power grid-connected system includes a generator set, a transmission line and a load control module. The generator set, the transmission line and the load control module are respectively corresponding to reference operation parameters. Each corresponding reference operation parameter is used to indicate the operation parameters of the generator set, the transmission line and the load control module when the offshore wind power grid-connected system is in a normal state. When the current timestamp is in any one of the multiple control state conversion time periods, the corresponding target system state is determined, and the target system operation information is determined from a preset relationship mapping table based on the target system state, and the system operation corresponding to the target system operation information is executed, including: In the case where the current timestamp is in the warning state time period, determining that the target system state corresponding to the warning state time period is the warning state, and obtaining the target system operation information corresponding to the warning state from the relationship mapping table, and pre-scheduling the generator set according to the corresponding target system operation information; In the case where the current timestamp is in the emergency time period, determining that the target system state corresponding to the emergency time period is an emergency state, and obtaining the target system operation information corresponding to the emergency state from the relationship mapping table, and controlling the transmission line to output a preset emergency transmission capacity according to the corresponding target system operation information, and at the same time shedding the load on the load control module, wherein the emergency transmission capacity is greater than the normal transmission capacity of the transmission line; In the case where the current timestamp is in the repair state time period, determining that the target system state corresponding to the repair state time period is a repair state, obtaining the target system operation information corresponding to the repair state from the relationship mapping table, and shedding the load of the load control module according to the corresponding target system operation information; When the current timestamp is in the normal state time period, the target system state corresponding to the normal state time period is determined to be the normal state, and the target system operation information corresponding to the normal state is obtained from the relationship mapping table, and according to the corresponding target system operation information, the generator set, the transmission line and the load control module are respectively controlled based on the corresponding reference operation parameters.

3. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 1, characterized in that: The gradient wind speed is calculated according to the following formula: in, is the gradient wind speed, is the proportionality factor, r ω is the reference distance, δ is the adjustment factor used to describe small changes in wind speed, is the distance between the wind farm and the typhoon center, t is the current timestamp, and ω is the current scene information; The wind power is calculated according to the following formula: in, is the wind power, indicating the wind speed at time t Under the condition, the maximum power point tracking output power of the wind turbine is V 启 V is the starting wind speed, the minimum wind speed at which the wind turbine starts to generate electricity. 额 is the rated wind speed, which is used to indicate the wind speed at which the wind turbine reaches its maximum power output. 停 P is the shutdown wind speed, which is used to indicate the wind speed at which the wind turbine stops operating to protect the equipment. 额 is the rated power output of the wind turbine, and τ is the rotor radius of the wind turbine.

4. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 1, characterized in that: The frequency safety constraint formula based on the system frequency response model and the preset system safety frequency threshold is constructed according to the following formula: Where Δf max is the preset system safety frequency threshold, f0 is the current frequency of the system, is the weight coefficient related to load change, which is used to measure the impact of power change caused by generator inertia on system frequency. is the power change of the lth load at time t and scenario ω, is the weight coefficient related to the system reserve power, which is used to quantify the contribution of frequency regulation reserve to system frequency stability. sys,t is the total reserve power of the system at time t, is the weight coefficient related to the system inertia, which is used to reflect the inhibitory effect of the system inertia on the frequency change. is the total inertia of the system at time t and scenario ω, is the weight coefficient related to system damping, which is used to indicate the ability to damp frequency oscillations. sys,t is the total damping coefficient of the system at time t, is a constant related to the system; The frequency safety constraint formula is obtained by converting the following formula using a piecewise linearization method of convex optimization: in, is the frequency deviation at the lowest point of the system frequency in the ω scenario at time t, D sys is the system damping parameter, R sys is the frequency regulation reserve of the system, T g is the time constant of the speed regulator of the thermal power unit, F sys is the power generation ratio of the system, is the system comprehensive inertia, ξ is the damping ratio, which indicates the degree of system damping, ω n is the natural frequency of the system, which is used to indicate the natural frequency of the system oscillation without damping, t nadir The timestamp of the lowest system frequency. Among them, ω d is the damped oscillation angular frequency, u g,t is the operating status of the generator set g at time t, is the maximum output power of generator set g, K g is the mechanical power gain factor of the thermal power unit, R g is the active power droop control coefficient of the thermal power unit, is the generator set, F g is the proportion of power generation by high-pressure boilers, R f is the droop control coefficient of the offshore wind farm, w is the offshore wind farm, For offshore wind farms, P f is the rated power of the offshore wind farm f, R s is the droop control coefficient of the energy storage device, P s is the output power of energy storage device s, s is a certain energy storage device, S is the battery energy storage system set, D g is the damping coefficient of the conventional generator set g.

5. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 4, characterized in that: A generator resource cost control model is constructed based on the generator startup cost, generator shutdown cost, generator startup operation identifier, generator shutdown operation identifier, and generator status information of the offshore wind power grid-connected system, and is obtained according to the following formula: Wherein, f(x) is the objective function corresponding to the resource cost control model of the generator set, c 开,g is the startup cost of the generator set, c 关,g is the shutdown cost of the generator set, α g,t is the generator set start operation identifier, β g,t The shutdown operation mark of the generator set, c T is the cost coefficient vector, x is the decision variable vector, △t is the time change, is the time set, is a generator set, and t is the current timestamp.

6. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 5, characterized in that: The first constraint formula includes a first sub-constraint formula, a second sub-constraint formula, a third sub-constraint formula and a fourth sub-constraint formula. The first constraint formula is constructed based on a preset minimum startup cost, a preset downtime duration, and a generator state constraint condition, and is obtained according to the following formula: The expression of the first sub-constraint is: The expression of the second sub-constraint is: The expression of the third sub-constraint is: The expression of the fourth sub-constraint is: in, is the shutdown state of the generator set at time t, α g,b is the starting state of the generator set at time t, β g,b is the shutdown state of the generator set at time b, u g,0 is the operating state of the generator set g at the initial time, UT g is the minimum start-up time of generator set g, DT g is the minimum shutdown time of the generator set g, UT r is the minimum start-up time of the generator set g in the initial state, DT r is the minimum shutdown time of generator set g in the initial state.

7. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 1, characterized in that: Based on the unit power generation fuel cost, energy storage charging and discharging cost, energy storage charging and discharging power, load shedding cost, and load shedding amount of the offshore wind power grid-connected system, a system load shedding response model is constructed, which is obtained according to the following formula: Among them, q(y ω ) is the objective function corresponding to the system load shedding response model, α g is the fuel cost for power generation of the unit, is the power generated by generator g at time t under scenario ω, c LCOE is the energy storage charging and discharging cost, is the energy storage charging and discharging power, is the load shedding cost, c VOLL is the load shedding cost, is the load shedding amount, and t is the current timestamp.

8. The grid optimization dispatching method for offshore wind power grid-connected system according to claim 1, characterized in that: The second constraint is obtained according to the following formula: Among them, u g,t is the generator set status information, is the minimum power limit of the generator set g, p g,t is the actual power generation of generator set g at time t, is the maximum power limit of the generator set g, R g,t is the spare capacity of generator set g at time t, used to cope with load changes or failures, is the actual power generation of generator set g at time t under scenario ω, is the maximum power boost capability provided by the generator set g within the time interval Δt, u g,t-1 is the operating state of the generator set g at time t-1, SU g is the starting power slope of generator set g, α g,t is the starting state of the generator set g at time t, SD is the maximum power reduction capability provided by the generator set g within the time interval Δt. g is the shutdown power slope of generator set g, β g,t is the shutdown state of the generator set g at time t, ω represents different scenarios, is an arbitrary timestamp, is the switch state indicator variable of line ij at time t and scenario ω, is the active power flow of line ij at time t and scenario ω, B ij is the value of the admittance matrix of line ij, is the phase angle of node i at time t and scenario ω, is the phase angle of node j at time t and scenario ω, i and j are nodes in the line respectively, ij is the transmission line connecting nodes i and j, is the maximum active power of line ij, is the state indicator variable of the disturbance at time t and scenario ω, is the maximum power change of line ij after considering the disturbance, is the maximum active power of line ij under the preset condition k, e is the energy state of the energy storage device, is the charging power of energy storage device s at time t and scenario ω, is the maximum charging power of the energy storage device s, is the discharge power of energy storage device s at time t and scenario ω, is the maximum discharge power of the energy storage device s, ch is the charging process, and dc is the discharging process.

9. A control device, characterized in that: It includes at least one control processor and a memory for communicating with the at least one control processor; the memory stores instructions that can be executed by the at least one control processor, and the instructions are executed by the at least one control processor so that the at least one control processor can execute the power grid optimization scheduling method for the offshore wind power grid-connected system as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the power grid optimization scheduling method for the offshore wind power grid-connected system as described in any one of claims 1 to 8.

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