Offshore wind storage control optimization method and system

Abstract

The invention discloses a control optimization method and system for offshore wind storage, and the method comprises the steps: building an objective function of the offshore wind storage with the lowest operation cost of the offshore wind storage as an objective according to the operation data of the offshore wind storage; according to the operation data of the offshore wind storage, an offshore wind power plant constraint condition and an energy storage system constraint condition are constructed respectively; solving the objective function based on an offshore wind plant constraint condition and an energy storage system constraint condition to obtain the optimal wind curtailment power and the optimal energy storage frequency modulation reserve capacity; and according to the optimal wind curtailment power and the optimal energy storage frequency modulation reserve capacity, respectively performing control optimization on the offshore wind plant and the energy storage system. The economic benefit and the energy utilization rate of offshore wind storage are improved by reducing the wind curtailment amount of the offshore wind plant and the frequency modulation cost of the energy storage system.

Description

Technical Field

[0001] The present application belongs to the field of control design of renewable energy power generation systems, and specifically relates to a control optimization method and system for offshore wind storage. Background Art

[0002] In new energy storage systems, wind and energy storage joint operation is a common application mode. By coordinating the operation of offshore wind farms and energy storage systems, wind energy can be better utilized, wind abandonment can be reduced, the economy and reliability of the power grid can be improved, and the joint operation of offshore wind and energy storage can be established. However, during the operation of offshore wind storage, multiple factors such as the uncertainty of wind power generation, the cost-effectiveness of energy storage systems, and the real-time needs of the power grid need to be considered in order to effectively reduce the total operating cost of offshore wind storage and improve energy utilization, thereby demonstrating the advantages of offshore wind storage in new energy systems.

[0003] The existing coordinated operation strategy for offshore wind storage is to obtain additional income by participating in the auxiliary service market of the power grid, such as frequency regulation, peak regulation and reactive power support, to offset part of the operating costs of offshore wind storage. However, the additional income obtained is not stable, and it is only considered from the perspective of operating costs, without considering the loss costs caused by reducing the amount of wind abandonment, and it is impossible to more effectively improve the economic benefits and energy utilization of offshore wind storage. Summary of the invention

[0004] This application proposes a control optimization method and system for offshore wind storage, which improves the economic benefits and energy utilization rate of offshore wind storage by reducing the amount of abandoned wind in offshore wind farms and the frequency regulation costs of energy storage systems.

[0005] A first aspect of the present application provides a control optimization method for offshore wind storage, the method comprising:

[0006] According to the operation data of offshore wind storage, the objective function of offshore wind storage is constructed with the goal of minimizing the operation cost of offshore wind storage; wherein the operation cost of offshore wind storage includes the abandoned wind loss cost of offshore wind farm and the charging, discharging and frequency regulation loss cost of energy storage system;

[0007] Based on the operation data of offshore wind storage, the constraints of offshore wind farm and energy storage system are constructed respectively;

[0008] Based on the constraints of the offshore wind farm and the energy storage system, the objective function is solved to obtain the optimal wind power abandonment and the optimal energy storage frequency regulation reserve capacity;

[0009] According to the optimal wind curtailment power and the optimal energy storage charging and discharging power, the offshore wind farm and energy storage system are controlled and optimized respectively.

[0010] The above scheme calculates the costs of offshore wind farms and energy storage systems in offshore wind storage respectively, and takes into account the impact of the wind abandonment of offshore wind farms on costs, as well as the impact of the frequency regulation costs of energy storage systems on costs during the calculation process, and constructs an objective function for offshore wind storage with the goal of minimizing the operating cost of offshore wind storage; and according to the limitations of equipment in the actual operation of offshore wind storage, constructs constraints, solves the objective function based on the constraints, and obtains the optimal wind abandonment power and the optimal energy storage charging and discharging power; by adjusting the wind abandonment of offshore wind farms and the frequency regulation costs of energy storage systems, the total operating cost of offshore wind storage can be reduced, thereby achieving an increase in the economic benefits of offshore wind storage while improving energy utilization.

[0011] In a possible implementation method of the first aspect, based on the operation data of the offshore wind storage, with the goal of minimizing the operation cost of the offshore wind storage, an objective function of the offshore wind storage is constructed, specifically:

[0012] According to the dispatching data and wind abandonment data of the offshore wind farm, the total operating cost and the wind abandonment loss cost of the offshore wind farm are calculated respectively to construct a first total operating cost;

[0013] According to the charging and discharging data and frequency modulation data of the energy storage system, the total operating cost of the energy storage system and the charging and discharging frequency modulation loss cost are calculated respectively to construct a second total operating cost;

[0014] An objective function of offshore wind storage is constructed with the goal of minimizing the sum of the first total operating cost and the second total operating cost.

[0015] When calculating the total operating cost of an offshore wind farm, the above scheme takes into account the impact of the abandoned wind loss cost on the cost, providing data support for reducing the total operating cost of the offshore wind farm by reducing the abandoned wind volume; when calculating the total operating cost of the energy storage system, the cost of charging and discharging frequency regulation is taken into account, providing data support for reducing the frequency regulation cost by improving the operating stability of the energy storage system to reduce the total operating cost of the energy storage system.

[0016] In a possible implementation method of the first aspect, the first total operating cost, the second total operating cost, and the objective function are specifically:

[0017] The calculation formula of the first total operating cost is:

[0018]

[0019] Where T is the total number of dispatching periods of offshore wind farms, is the total operating cost of the offshore wind farm at time t, n is the total number of offshore wind farms, and is the frequency regulation reserve cost and reserve capacity of the i-th offshore wind farm at time t, ci is the wind abandonment penalty coefficient of the i-th offshore wind farm, is the load reduction ratio of the i-th offshore wind farm at time t, is the power forecast value of the i-th offshore wind farm at time t, is the passive abandoned wind power of the i-th offshore wind farm at time t;

[0020] The calculation formula of the second total operating cost is:

[0021]

[0022] In the formula, is the total operating cost of the energy storage system at time t, c bc and c bd are the charging cost coefficient and discharging cost coefficient of the energy storage system, and is the charging power and discharging power of the energy storage system at time t, and are the positive frequency regulation reserve cost coefficient and negative frequency regulation reserve cost coefficient of the energy storage system, and are the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided by the energy storage system when discharging at time t, and The positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided when the energy storage system is charged at time t;

[0023] The calculation formula of the objective function is:

[0024]

[0025] Wherein, F is the objective function.

[0026] In a possible implementation method of the first aspect, based on the operation data of the offshore wind storage, offshore wind farm constraints and energy storage system constraints are respectively constructed, specifically:

[0027] Based on the power limit and wind abandonment requirement of the offshore wind farm, constructing the active power balance constraint and wind abandonment load reduction constraint of the offshore wind farm according to the operation data;

[0028] Based on the power limit and device status of the energy storage system, the output range constraint of the energy storage system and the charge state constraint of the energy storage device are constructed according to the operation data.

[0029] The above scheme constructs constraints based on the equipment limitations and operating requirements of offshore wind storage in actual operation, making the results of objective function calculation more reasonable and in line with actual conditions.

[0030] In a possible implementation method of the first aspect, the active power balance constraint, the wind abandonment load reduction constraint, the output range constraint, and the energy storage device charge state constraint are specifically:

[0031] The active power balance constraint is specifically expressed as follows:

[0032]

[0033] In the formula, is the actual power value of the i-th offshore wind farm at time t, is the load power forecast value at time t, is the load power prediction error at time t;

[0034] The load reduction constraint of abandoned wind volume is specifically expressed as:

[0035]

[0036] In the formula, is the load reduction ratio of the i-th offshore wind farm at time t, d max is the maximum load reduction level for offshore wind farms.

[0037] The output range constraint is specifically expressed as:

[0038]

[0039] In the formula, are the minimum allowable power and maximum allowable power of the energy storage system when discharging, They are the minimum allowable power and maximum allowable power when charging the energy storage device. and is the charging power and discharging power of the energy storage system at time t;

[0040] The energy storage device charge state constraint is specifically expressed as:

[0041]

[0042] In the formula, SOC t is the state of charge of the energy storage system at time t, SOC min and SOC max They are the minimum state of charge and maximum state of charge allowed by the energy storage system, SOC t-1 is the state of charge of the energy storage system at time t-1, δ is the self-discharge rate of the energy storage system, η c and η d are the charging efficiency and discharging efficiency of the energy storage system, Δt is the charging and discharging time interval, S b is the equipment capacity of the energy storage system.

[0043] In a possible implementation method of the first aspect, the offshore wind farm and the energy storage system are controlled and optimized respectively according to the optimal wind abandonment power and the optimal energy storage charging and discharging power, specifically:

[0044] According to the optimal wind abandonment power, the active wind abandonment and passive wind abandonment of the offshore wind farm are adjusted to optimize the total wind abandonment of the offshore wind farm;

[0045] According to the optimal energy storage charging and discharging power, the frequency regulation reserve capacity of the energy storage system during charging and discharging is adjusted to optimize the frequency regulation loss of the energy storage system.

[0046] The above scheme reduces internal transmission losses by reducing the amount of wind abandoned in offshore wind farms based on the optimal wind abandonment power, so that offshore wind farms can improve their total operating costs by promoting wind power consumption; according to the optimal energy storage charging and discharging power, the frequency of charging and discharging frequency modulation and the frequency modulation reserve capacity are reduced by improving the operating stability of the energy storage system, so that the energy storage system can improve its total operating costs by reducing the cost required for frequency modulation, thereby improving energy utilization while achieving the economic benefits of offshore wind storage.

[0047] A second aspect of the present application provides a control optimization system for offshore wind storage, the system comprising: an objective function construction module, a constraint condition construction module, a function solving module and an offshore wind storage regulation module;

[0048] The objective function construction module is used to construct an objective function of offshore wind storage based on the operation data of offshore wind storage, with the goal of minimizing the operation cost of offshore wind storage; wherein the operation cost of offshore wind storage includes the abandoned wind loss cost of offshore wind farms and the charging and discharging frequency regulation loss cost of energy storage systems;

[0049] The constraint condition building module is used to build offshore wind farm constraint conditions and energy storage system constraint conditions respectively according to the operation data of offshore wind storage;

[0050] The function solving module is used to solve the objective function based on the constraints of the offshore wind farm and the constraints of the energy storage system to obtain the optimal wind power abandonment and the optimal energy storage frequency regulation reserve capacity;

[0051] The offshore wind storage optimization module is used to control and optimize the offshore wind farm and energy storage system according to the optimal wind abandonment power and the optimal energy storage frequency regulation reserve capacity.

[0052] In a possible implementation of the second aspect, the objective function construction module includes: an objective function construction unit;

[0053] Among them, the objective function construction unit is used to calculate the total operating cost and the wind abandonment loss cost of the offshore wind farm according to the scheduling data and wind abandonment data of the offshore wind farm, and construct a first total operating cost; calculate the total operating cost and the charging and discharging frequency regulation loss cost of the energy storage system according to the charging and discharging data and frequency regulation data of the energy storage system, and construct a second total operating cost; and construct the objective function of the offshore wind storage with the goal of minimizing the sum of the first total operating cost and the second total operating cost.

[0054] In a possible implementation of the second aspect, the constraint condition construction module includes: a constraint condition construction unit;

[0055] Among them, the constraint condition construction unit is used to construct the active power balance constraint and wind abandonment load reduction constraint of the offshore wind farm based on the power limit and wind abandonment requirement of the offshore wind farm according to the operating data; based on the power limit and equipment status of the energy storage system, construct the output range constraint of the energy storage system and the charge state constraint of the energy storage device according to the operating data.

[0056] In a possible implementation of the second aspect, the offshore wind storage optimization module includes: an offshore wind storage optimization unit;

[0057] Among them, the offshore wind storage optimization unit is used to adjust the active wind abandonment and passive wind abandonment of the offshore wind farm according to the optimal wind abandonment power, so as to optimize the total wind abandonment of the offshore wind farm; according to the optimal energy storage frequency regulation reserve capacity, the frequency regulation reserve capacity of the energy storage system during charging and discharging is adjusted to optimize the frequency regulation loss of the energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0059] Figure 1 It is a specific flow chart of a control optimization method for offshore wind storage provided by a certain embodiment of the present application;

[0060] Figure 2 A structural diagram of a control optimization system for offshore wind storage provided in a certain embodiment of the present application. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0062] It should be understood that the step numbers used in this article are only for the convenience of description and are not intended to limit the order in which the steps are executed.

[0063] First embodiment

[0064] The existing offshore wind storage control strategy mainly includes accurately predicting the power generation of wind farms by predicting wind power and intelligently dispatching the charging and discharging of energy storage systems according to grid demand to improve the energy utilization rate of offshore wind farms, and obtaining additional income by participating in the auxiliary service market of the grid to improve the economic benefits of offshore wind storage. However, due to the instability of offshore wind storage, the above scheme cannot fundamentally solve the problem. Therefore, it is necessary to reduce the cost of offshore wind storage in frequency regulation of energy storage systems and reduce the amount of abandoned wind, which can stably ensure the reduction of loss costs, to achieve the economic efficiency of offshore wind storage, effectively promote wind power consumption, and fundamentally improve energy utilization.

[0065] like Figure 1 As shown, Figure 1 A specific flow chart of a control optimization method for offshore wind storage is provided for a certain embodiment of the present application. The control optimization method for offshore wind storage in this embodiment includes steps S1 to S4, which are described in detail as follows:

[0066] Step S1, constructing an objective function of the offshore wind storage based on the operating data of the offshore wind storage and taking the lowest operating cost of the offshore wind storage as the goal.

[0067] In the embodiment of the present application, the source of the total cost of offshore wind storage is first clarified. Because offshore wind storage actually includes offshore wind farms and energy storage systems, the total cost of offshore wind farms and the total cost of energy storage systems need to be calculated separately.

[0068] The total cost of an offshore wind farm includes the total operating cost of the offshore wind farm and the cost of wind abandonment. Because the total operating cost is affected by many factors that are difficult to adjust, and in order to improve energy utilization, the embodiment of the present application mainly reduces the cost of wind abandonment. Among them, abandoned wind refers to wind energy that is not effectively utilized due to various reasons in the process of wind power generation. Reducing the abandoned wind can effectively improve the utilization rate and efficiency of wind power. In general wind farms, the abandoned wind is divided into active abandoned wind and passive abandoned wind according to a certain load reduction ratio. In the embodiment of the present application, the beneficial effect of reducing the abandoned wind is achieved by adjusting the load reduction ratio.

[0069] Therefore, the loss cost of wind abandonment includes the loss cost of active wind abandonment and the loss cost of passive wind abandonment. Each offshore wind farm has a certain load reduction ratio of active wind abandonment and passive wind abandonment. According to the load reduction ratio, the active wind abandonment power and passive wind abandonment power of each offshore wind farm can be known.

[0070] Therefore, according to the total number of offshore wind farms and dispatching data, the total operating cost of offshore wind farms can be calculated. According to the active wind curtailment power, passive wind curtailment power and the set wind curtailment penalty coefficient of the offshore wind farm, the wind curtailment loss cost can be calculated, and the first total operating cost representing the total cost of the offshore wind farm can be further obtained. The specific calculation formula is:

[0071]

[0072] Where T is the total number of dispatching periods of offshore wind farms, is the total operating cost of the offshore wind farm at time t, n is the total number of offshore wind farms, and is the frequency regulation reserve cost and reserve capacity of the i-th offshore wind farm at time t, c i is the wind abandonment penalty coefficient of the i-th offshore wind farm, is the load reduction ratio of the i-th offshore wind farm at time t, is the power forecast value of the i-th offshore wind farm at time t, is the passive wind power abandonment of the i-th offshore wind farm at time t.

[0073] The total cost of the energy storage system includes the total operating cost of the energy storage system and the cost of charge, discharge and frequency modulation losses. The basic principle of energy storage charge, discharge and frequency modulation is to balance the supply and demand of the power grid by controlling the charge and discharge process of the energy storage system, thereby stabilizing the frequency of the power system. This process involves operations such as setting charge and discharge parameters, starting charge and discharge, monitoring battery status, adjusting charge and discharge power, and controlling charge and discharge time. In the embodiments of the present application, the beneficial effect of reducing the cost of charge, discharge and frequency modulation losses of the energy storage system is mainly achieved by adjusting the charge and discharge power of the energy storage device and the allocation of frequency modulation reserve capacity during charge and discharge.

[0074] Furthermore, the reserve capacity refers to the active power reserve reserved for ensuring power quality and safe and stable operation of the system in case of emergencies in addition to meeting the expected load demand. When the system frequency is lower than the lower limit of the normal frequency range, it can be adjusted by calling the reserve capacity.

[0075] Therefore, the total operating cost of the energy storage system can be calculated based on the charging and discharging data and frequency modulation data of the energy storage system. The charging and discharging frequency modulation loss cost can be calculated based on the charging and discharging power of the energy storage system and the allocation of the frequency modulation reserve capacity during charging and discharging, and the second total operating cost representing the total cost of the energy storage system can be further obtained. The specific calculation formula is:

[0076]

[0077] In the formula, is the total operating cost of the energy storage system at time t, c bc and c bd are the charging cost coefficient and discharging cost coefficient of the energy storage system, and is the charging power and discharging power of the energy storage system at time t, and are the positive frequency regulation reserve cost coefficient and negative frequency regulation reserve cost coefficient of the energy storage system, and are the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided by the energy storage system when discharging at time t, and It is the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided when the energy storage system is charging at time t.

[0078] Furthermore, the objective function of offshore wind storage is constructed with the goal of minimizing the sum of the first total operating cost and the second total operating cost. The calculation formula of the objective function is:

[0079]

[0080] Wherein, F is the objective function.

[0081] Step S2, constructing offshore wind farm constraints and energy storage system constraints respectively according to the operating data of the offshore wind storage.

[0082] In the embodiment of the present application, according to the limitations of hardware equipment and safety requirements of the offshore wind farm and the energy storage system during actual operation, offshore wind farm constraints and energy storage system constraints are respectively constructed.

[0083] First, based on the power data of the offshore wind farm, the active power balance constraint is constructed. The specific formula is:

[0084]

[0085] In the formula, is the actual power value of the i-th offshore wind farm at time t, is the load power forecast value at time t, is the load power prediction error at time t.

[0086] Based on the load reduction level of offshore wind farms, the load reduction constraint of abandoned wind volume is constructed. The specific expression is:

[0087]

[0088] In the formula, is the load reduction ratio of the i-th offshore wind farm at time t, d max is the maximum load reduction level for offshore wind farms.

[0089] Then, based on the power limit of the equipment in the energy storage system, the output range constraint is constructed. The specific expression is:

[0090]

[0091] In the formula, are the minimum allowable power and maximum allowable power of the energy storage system when discharging, They are the minimum allowable power and maximum allowable power when charging the energy storage device. and are the charging power and discharging power of the energy storage system at time t.

[0092] Based on the state of charge restriction conditions and device status data of the equipment in the energy storage system, the state of charge constraint of the energy storage equipment is constructed. The specific expression is:

[0093]

[0094] In the formula, SOC t is the state of charge of the energy storage system at time t, SOC min and SOC max They are the minimum state of charge and maximum state of charge allowed by the energy storage system, SOC t-1 is the state of charge of the energy storage system at time t-1, δ is the self-discharge rate of the energy storage system, η c and η d are the charging efficiency and discharging efficiency of the energy storage system, Δt is the charging and discharging time interval, S b is the equipment capacity of the energy storage system.

[0095] Based on the above constraints, an offshore wind storage control strategy that is more in line with the actual situation can be solved.

[0096] Step S3, based on the constraints of the offshore wind farm and the constraints of the energy storage system, solving the objective function to obtain the optimal wind power abandonment and the optimal energy storage frequency regulation reserve capacity.

[0097] In the embodiment of the present application, based on the constraints of the offshore wind farm and the constraints of the energy storage system, the objective function is solved to obtain the optimal offshore wind energy storage control strategy.

[0098] The offshore wind storage control strategy includes an offshore wind farm wind abandonment volume adjustment strategy, and an energy storage system optimal equipment charging and discharging power and frequency regulation standby capacity adjustment strategy.

[0099] According to the wind abandonment adjustment strategy, the optimal wind abandonment power can be obtained for adjusting the ratio of active wind abandonment power and passive wind abandonment power of the offshore wind farm, thereby reducing the wind abandonment loss cost.

[0100] The charging and discharging power of the energy storage device can be adjusted according to the optimal device charging and discharging power. The optimal energy storage frequency regulation reserve capacity can be obtained according to the frequency regulation reserve capacity adjustment strategy, which is used to allocate the frequency regulation reserve capacity of the energy storage device during charging and discharging. When assisting the power grid system in frequency regulation, the charging and discharging frequency regulation loss cost can also be reduced.

[0101] Step S4, controlling and optimizing the offshore wind farm and the energy storage system respectively according to the optimal wind curtailment power and the optimal energy storage frequency regulation reserve capacity.

[0102] In the embodiment of the present application, based on the optimal wind curtailment power, the optimal energy storage frequency regulation standby capacity and the optimal equipment charging and discharging power, the operation of the offshore wind farm and the energy storage system are adjusted respectively to optimize the total wind curtailment of the offshore wind farm and the frequency regulation loss of the energy storage system, which effectively reduces the operating cost of the offshore wind storage and improves energy utilization overall.

[0103] Implementing the embodiments of the present application has the following beneficial effects:

[0104] The embodiment of the present application constructs an objective function for calculating the total operating cost of offshore wind storage by considering the loss cost caused by the abandoned wind volume of the offshore wind farm and the loss cost caused by the energy storage system when participating in frequency regulation, and simultaneously constructs constraints of the offshore wind farm and the energy storage system respectively, and calculates the objective function based on the constraints, and obtains and adjusts the abandoned wind volume of the offshore wind farm and the charging and discharging power and frequency regulation reserve capacity ratio of the energy storage system, thereby effectively improving the energy utilization rate of the offshore wind farm while achieving the lowest total operating cost of the offshore wind storage, and reducing the frequency regulation cost of the energy storage system while ensuring the stable operation of the power grid system.

[0105] Second embodiment

[0106] Further, in order to execute the control optimization system of the offshore wind storage corresponding to the above method embodiment to achieve the corresponding functions and technical effects, Figure 2A structural diagram of a control optimization system for offshore wind storage is provided. For ease of description, only the parts related to this embodiment are shown. The control optimization system for offshore wind storage provided by the embodiment of the present application includes:

[0107] The objective function construction module 201 is used to construct an objective function of the offshore wind storage based on the operating data of the offshore wind storage, with the goal of minimizing the operating cost of the offshore wind storage; wherein the operating cost of the offshore wind storage includes the cost of abandoned wind loss in the offshore wind farm and the cost of charging, discharging and frequency regulation loss of the energy storage system.

[0108] The constraint condition building module 202 is used to build offshore wind farm constraint conditions and energy storage system constraint conditions respectively according to the operation data of the offshore wind storage.

[0109] The function solving module 203 is used to solve the objective function based on the constraints of the offshore wind farm and the constraints of the energy storage system to obtain the optimal wind power abandonment and the optimal energy storage frequency regulation reserve capacity.

[0110] In the embodiment of the present application, based on the constraints of the offshore wind farm and the constraints of the energy storage system, the objective function is solved to obtain the optimal offshore wind energy storage control strategy.

[0111] The offshore wind storage control strategy includes an offshore wind farm wind abandonment volume adjustment strategy, and an energy storage system optimal equipment charging and discharging power and frequency regulation standby capacity adjustment strategy.

[0112] According to the wind abandonment adjustment strategy, the optimal wind abandonment power can be obtained for adjusting the ratio of active wind abandonment power and passive wind abandonment power of the offshore wind farm, thereby reducing the wind abandonment loss cost.

[0113] The charging and discharging power of the energy storage device can be adjusted according to the optimal device charging and discharging power. The optimal energy storage frequency regulation reserve capacity can be obtained according to the frequency regulation reserve capacity adjustment strategy, which is used to allocate the frequency regulation reserve capacity of the energy storage device during charging and discharging. When assisting the power grid system in frequency regulation, the charging and discharging frequency regulation loss cost can also be reduced.

[0114] The offshore wind storage optimization module 204 is used to control and optimize the offshore wind farm and the energy storage system according to the optimal wind abandonment power and the optimal energy storage frequency regulation reserve capacity.

[0115] In some embodiments, the objective function construction module 201 further includes:

[0116] The objective function construction unit is used to calculate the total operating cost and the wind abandonment loss cost of the offshore wind farm according to the scheduling data and wind abandonment data of the offshore wind farm, and construct a first total operating cost; calculate the total operating cost and the charging, discharging and frequency regulation loss cost of the energy storage system according to the charging, discharging and frequency regulation data of the energy storage system, and construct a second total operating cost; and construct the objective function of the offshore wind storage with the goal of minimizing the sum of the first total operating cost and the second total operating cost.

[0117] The total cost of an offshore wind farm includes the total operating cost of the offshore wind farm and the cost of wind abandonment. Because the total operating cost is affected by many factors that are difficult to adjust, and in order to improve energy utilization, the embodiment of the present application mainly reduces the cost of wind abandonment. Among them, abandoned wind refers to wind energy that is not effectively utilized due to various reasons in the process of wind power generation. Reducing the abandoned wind can effectively improve the utilization rate and efficiency of wind power. In general wind farms, the abandoned wind is divided into active abandoned wind and passive abandoned wind according to a certain load reduction ratio. In the embodiment of the present application, the beneficial effect of reducing the abandoned wind is achieved by adjusting the load reduction ratio.

[0118] Therefore, the loss cost of wind abandonment includes the loss cost of active wind abandonment and the loss cost of passive wind abandonment. Each offshore wind farm has a certain load reduction ratio of active wind abandonment and passive wind abandonment. According to the load reduction ratio, the active wind abandonment power and passive wind abandonment power of each offshore wind farm can be known.

[0119] Therefore, according to the total number of offshore wind farms and dispatching data, the total operating cost of offshore wind farms can be calculated. According to the active wind curtailment power, passive wind curtailment power and the set wind curtailment penalty coefficient of the offshore wind farm, the wind curtailment loss cost can be calculated, and the first total operating cost representing the total cost of the offshore wind farm can be further obtained. The specific calculation formula is:

[0120]

[0121] Where T is the total number of dispatching periods of offshore wind farms, is the total operating cost of the offshore wind farm at time t, n is the total number of offshore wind farms, and is the frequency regulation reserve cost and reserve capacity of the i-th offshore wind farm at time t, c i is the wind abandonment penalty coefficient of the i-th offshore wind farm, is the load reduction ratio of the i-th offshore wind farm at time t, is the power forecast value of the i-th offshore wind farm at time t, is the passive wind power abandonment of the i-th offshore wind farm at time t.

[0122] The total cost of the energy storage system includes the total operating cost of the energy storage system and the cost of charge, discharge and frequency modulation losses. The basic principle of energy storage charge, discharge and frequency modulation is to balance the supply and demand of the power grid by controlling the charge and discharge process of the energy storage system, thereby stabilizing the frequency of the power system. This process involves operations such as setting charge and discharge parameters, starting charge and discharge, monitoring battery status, adjusting charge and discharge power, and controlling charge and discharge time. In the embodiments of the present application, the beneficial effect of reducing the cost of charge, discharge and frequency modulation losses of the energy storage system is mainly achieved by adjusting the charge and discharge power of the energy storage device and the allocation of frequency modulation reserve capacity during charge and discharge.

[0123] Furthermore, the reserve capacity refers to the active power reserve reserved for ensuring power quality and safe and stable operation of the system in case of emergencies in addition to meeting the expected load demand. When the system frequency is lower than the lower limit of the normal frequency range, it can be adjusted by calling the reserve capacity.

[0124] Therefore, the total operating cost of the energy storage system can be calculated based on the charging and discharging data and frequency modulation data of the energy storage system. The charging and discharging frequency modulation loss cost can be calculated based on the charging and discharging power of the energy storage system and the allocation of the frequency modulation reserve capacity during charging and discharging, and the second total operating cost representing the total cost of the energy storage system can be further obtained. The specific calculation formula is:

[0125]

[0126] In the formula, is the total operating cost of the energy storage system at time t, c bc and c bd are the charging cost coefficient and discharging cost coefficient of the energy storage system, and is the charging power and discharging power of the energy storage system at time t, and are the positive frequency regulation reserve cost coefficient and negative frequency regulation reserve cost coefficient of the energy storage system, and are the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided by the energy storage system when discharging at time t, and It is the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided when the energy storage system is charging at time t.

[0127] Furthermore, the objective function of offshore wind storage is constructed with the goal of minimizing the sum of the first total operating cost and the second total operating cost. The calculation formula of the objective function is:

[0128]

[0129] Wherein, F is the objective function.

[0130] In some embodiments, the constraint condition building module 202 further includes:

[0131] A constraint condition construction unit is used to construct the active power balance constraint and wind abandonment load reduction constraint of the offshore wind farm based on the power limit and wind abandonment requirement of the offshore wind farm according to the operating data; based on the power limit and equipment status of the energy storage system, construct the output range constraint of the energy storage system and the charge state constraint of the energy storage device according to the operating data.

[0132] According to the limitations of hardware equipment and safety requirements of offshore wind farms and energy storage systems during actual operation, offshore wind farm constraints and energy storage system constraints are constructed respectively.

[0133] First, based on the power data of the offshore wind farm, the active power balance constraint is constructed. The specific formula is:

[0134]

[0135] In the formula, is the actual power value of the i-th offshore wind farm at time t, is the load power forecast value at time t, is the load power prediction error at time t.

[0136] Based on the load reduction level of offshore wind farms, the load reduction constraint of abandoned wind volume is constructed. The specific expression is:

[0137]

[0138] In the formula, is the load reduction ratio of the i-th offshore wind farm at time t, d max is the maximum load reduction level for offshore wind farms.

[0139] Then, based on the power limit of the equipment in the energy storage system, the output range constraint is constructed. The specific expression is:

[0140]

[0141] In the formula, are the minimum allowable power and maximum allowable power of the energy storage system when discharging, They are the minimum allowable power and maximum allowable power when charging the energy storage device. and are the charging power and discharging power of the energy storage system at time t.

[0142] Based on the state of charge restriction conditions and device status data of the equipment in the energy storage system, the state of charge constraint of the energy storage equipment is constructed. The specific expression is:

[0143]

[0144] In the formula, SOC t is the state of charge of the energy storage system at time t, SOC min and SOC max They are the minimum state of charge and maximum state of charge allowed by the energy storage system, SOC t-1 is the state of charge of the energy storage system at time t-1, δ is the self-discharge rate of the energy storage system, η c and η d are the charging efficiency and discharging efficiency of the energy storage system, Δt is the charging and discharging time interval, S b is the equipment capacity of the energy storage system.

[0145] Based on the above constraints, an offshore wind storage control strategy that is more in line with the actual situation can be solved.

[0146] In some embodiments, the offshore wind storage optimization module 204 further includes:

[0147] The offshore wind storage optimization unit is used to adjust the active and passive wind abandonment of the offshore wind farm according to the optimal wind abandonment power to optimize the total wind abandonment of the offshore wind farm; according to the optimal energy storage frequency regulation reserve capacity, the frequency regulation reserve capacity of the energy storage system during charging and discharging is adjusted to optimize the frequency regulation loss of the energy storage system.

[0148] Implementing the embodiments of the present application has the following beneficial effects:

[0149] The embodiment of the present application calculates the optimal wind abandonment power for adjusting the wind abandonment volume of the offshore wind farm to reduce the wind abandonment loss cost, and calculates the optimal frequency regulation reserve capacity and charging and discharging power for adjusting the frequency regulation loss cost of the energy storage system, thereby improving the economic benefits of offshore wind storage and improving energy utilization while ensuring stable system operation.

[0150] The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present application in detail. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the scope of protection of the present application. It is particularly pointed out that for those skilled in the art, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A control optimization method for offshore wind storage, characterized in that: include: According to the operation data of offshore wind storage, the objective function of offshore wind storage is constructed with the goal of minimizing the operation cost of offshore wind storage; wherein the operation cost of offshore wind storage includes the abandoned wind loss cost of offshore wind farm and the charging, discharging and frequency regulation loss cost of energy storage system; Based on the operation data of offshore wind storage, the constraints of offshore wind farm and energy storage system are constructed respectively; Based on the constraints of the offshore wind farm and the energy storage system, the objective function is solved to obtain the optimal wind abandonment power and the optimal energy storage charging and discharging power; According to the optimal wind curtailment power and the optimal energy storage charging and discharging power, the offshore wind farm and energy storage system are controlled and optimized respectively.

2. The control optimization method for offshore wind storage according to claim 1 is characterized in that: According to the operation data of offshore wind storage, the objective function of offshore wind storage is constructed with the goal of minimizing the operation cost of offshore wind storage, which is specifically: According to the dispatching data and wind abandonment data of the offshore wind farm, the total operating cost and the wind abandonment loss cost of the offshore wind farm are calculated respectively to construct a first total operating cost; According to the charging and discharging data and frequency modulation data of the energy storage system, the total operating cost of the energy storage system and the charging and discharging frequency modulation loss cost are calculated respectively to construct a second total operating cost; An objective function of offshore wind storage is constructed with the goal of minimizing the sum of the first total operating cost and the second total operating cost.

3. The control optimization method for offshore wind storage according to claim 2 is characterized in that: The first total operating cost, the second total operating cost and the objective function are specifically: The calculation formula of the first total operating cost is: Where T is the total number of dispatching periods of offshore wind farms, is the total operating cost of the offshore wind farm at time t, n is the total number of offshore wind farms, and is the frequency regulation reserve cost and reserve capacity of the i-th offshore wind farm at time t, c i is the wind abandonment penalty coefficient of the i-th offshore wind farm, is the load reduction ratio of the i-th offshore wind farm at time t, is the power forecast value of the i-th offshore wind farm at time t, is the passive abandoned wind power of the i-th offshore wind farm at time t; The calculation formula of the second total operating cost is: In the formula, is the total operating cost of the energy storage system at time t, c bc and c bd are the charging cost coefficient and discharging cost coefficient of the energy storage system, and is the charging power and discharging power of the energy storage system at time t, and are the positive frequency regulation reserve cost coefficient and negative frequency regulation reserve cost coefficient of the energy storage system, and are the positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided by the energy storage system when discharging at time t, and The positive frequency regulation reserve capacity and negative frequency regulation reserve capacity provided when the energy storage system is charged at time t; The calculation formula of the objective function is: Wherein, F is the objective function.

4. The control optimization method for offshore wind storage according to claim 1, characterized in that: According to the operation data of offshore wind storage, the constraints of offshore wind farm and energy storage system are respectively constructed, which are specifically: Based on the power limit and wind abandonment requirement of the offshore wind farm, constructing the active power balance constraint and wind abandonment load reduction constraint of the offshore wind farm according to the operation data; Based on the power limit and device status of the energy storage system, the output range constraint of the energy storage system and the charge state constraint of the energy storage device are constructed according to the operation data.

5. The control optimization method for offshore wind storage according to claim 4 is characterized in that: The active power balance constraint, wind curtailment load reduction constraint, output range constraint and energy storage device charge state constraint are specifically: The active power balance constraint is specifically expressed as follows: In the formula, is the actual power value of the i-th offshore wind farm at time t, is the load power forecast value at time t, is the load power prediction error at time t; The load reduction constraint of abandoned wind volume is specifically expressed as: In the formula, is the load reduction ratio of the i-th offshore wind farm at time t, d max is the maximum load reduction level for offshore wind farms; The output range constraint is specifically expressed as: In the formula, are the minimum allowable power and maximum allowable power of the energy storage system when discharging, They are the minimum allowable power and maximum allowable power when charging the energy storage device. and is the charging power and discharging power of the energy storage system at time t; The energy storage device charge state constraint is specifically expressed as: In the formula, SOC t is the state of charge of the energy storage system at time t, SOC min and SOC max They are the minimum state of charge and maximum state of charge allowed by the energy storage system, SOC t-1 is the state of charge of the energy storage system at time t-1, δ is the self-discharge rate of the energy storage system, η c and η d are the charging efficiency and discharging efficiency of the energy storage system, Δt is the charging and discharging time interval, S b is the equipment capacity of the energy storage system.

6. The control optimization method for offshore wind storage according to claim 1, characterized in that: The offshore wind farm and the energy storage system are controlled and optimized according to the optimal wind abandonment power and the optimal energy storage charging and discharging power, specifically: According to the optimal wind abandonment power, the active wind abandonment and passive wind abandonment of the offshore wind farm are adjusted to optimize the total wind abandonment of the offshore wind farm; According to the optimal energy storage charging and discharging power, the frequency regulation reserve capacity of the energy storage system is adjusted during charging and discharging to optimize the frequency regulation loss of the energy storage system.

7. A control optimization system for offshore wind storage, characterized in that: include: Objective function building module, constraint condition building module, function solving module and offshore wind storage regulation module; The objective function construction module is used to construct an objective function of offshore wind storage based on the operation data of offshore wind storage, with the goal of minimizing the operation cost of offshore wind storage; wherein the operation cost of offshore wind storage includes the abandoned wind loss cost of offshore wind farms and the charging and discharging frequency regulation loss cost of energy storage systems; The constraint condition building module is used to build offshore wind farm constraint conditions and energy storage system constraint conditions respectively according to the operation data of offshore wind storage; The function solving module is used to solve the objective function based on the constraints of the offshore wind farm and the constraints of the energy storage system to obtain the optimal wind abandonment power and the optimal energy storage charging and discharging power; The offshore wind storage optimization module is used to control and optimize the offshore wind farm and energy storage system according to the optimal wind abandonment power and the optimal energy storage charging and discharging power.

8. The control optimization system for offshore wind storage according to claim 7 is characterized in that: The objective function construction module includes: an objective function construction unit; Among them, the objective function construction unit is used to calculate the total operating cost and the wind abandonment loss cost of the offshore wind farm according to the scheduling data and wind abandonment data of the offshore wind farm, and construct a first total operating cost; calculate the total operating cost and the charging and discharging frequency regulation loss cost of the energy storage system according to the charging and discharging data and frequency regulation data of the energy storage system, and construct a second total operating cost; and construct the objective function of the offshore wind storage with the goal of minimizing the sum of the first total operating cost and the second total operating cost.

9. The control optimization system for offshore wind storage according to claim 7, characterized in that: The constraint condition construction module includes: a constraint condition construction unit; Among them, the constraint condition construction unit is used to construct the active power balance constraint and wind abandonment load reduction constraint of the offshore wind farm based on the power limit and wind abandonment requirement of the offshore wind farm according to the operating data; based on the power limit and equipment status of the energy storage system, construct the output range constraint of the energy storage system and the charge state constraint of the energy storage device according to the operating data.

10. The control optimization system for offshore wind storage according to claim 7, characterized in that: The offshore wind storage optimization module comprises: an offshore wind storage optimization unit; Among them, the offshore wind storage optimization unit is used to adjust the active wind abandonment and passive wind abandonment of the offshore wind farm according to the optimal wind abandonment power, so as to optimize the total wind abandonment of the offshore wind farm; according to the optimal energy storage frequency regulation reserve capacity, the frequency regulation reserve capacity of the energy storage system during charging and discharging is adjusted to optimize the frequency regulation loss of the energy storage system.

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