Energy storage optimal configuration method considering new energy-power grid-user capacity sharing

Abstract

The invention discloses an energy storage optimal configuration method considering new energy-power grid-user capacity sharing. The method comprises the following steps: step 1, constructing a new energy-power grid-user side energy storage configuration model; 2, constructing a new energy-power grid-user side energy storage sharing strategy; and step 3, based on the energy storage configuration model and the energy storage sharing strategy, establishing a new energy-power grid-user side energy storage optimization scheduling model. And the access number of reactive compensation equipment is reduced, so that unnecessary communication time, regulation and control cost and equipment access investment cost are reduced. The problem of resource utilization rate reduction due to new energy output reduction is relieved, and power consumer income is guaranteed; energy storage is configured on the power generation side, so that the problems of stabilizing output fluctuation, tracking a power generation plan, reducing prediction errors and reducing wind curtailment or light curtailment can be effectively solved.

Description

Technical Field

[0001] The invention relates to an energy storage optimization configuration method taking into account new energy, power grid and user capacity sharing, and belongs to the field of power system operation and control. Background Art

[0002] The proposal of the goals of "carbon peak" and "carbon neutrality" has further accelerated the development of new energy in my country. However, the contradiction between the difficulty of absorbing new energy, mainly wind power and photovoltaic power, when it is in high demand and the difficulty of ensuring power supply when it is in low demand is prominent, thus putting forward higher requirements for the flexibility of the new power system.

[0003] In the traditional system dominated by coal-fired power, the proportion of new energy is relatively low, and relying on adjustable power supply installation can ensure the balance of supply and demand and safe and stable operation of the power system. However, with the large-scale grid connection of new energy, power quality problems caused by its volatility, randomness, uncertainty, etc. are emerging in an endless stream, and the consumption rate of new energy is also difficult to increase. In order to solve the power quality problems caused by the large-scale grid connection of new energy, most of the research on energy storage configuration is aimed at new energy sites, power grids or users, and the energy storage configuration capacity is determined by maximizing the benefits of a single energy storage owner. This makes it difficult to fully utilize the energy storage capacity, redundant energy storage resource configuration, and increases the investment cost of energy storage. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies of the above-mentioned prior art, thereby providing a storage optimization configuration method for new energy-grid-user capacity sharing, reducing the number of access to reactive compensation equipment, thereby reducing unnecessary communication time, regulation costs, and equipment access investment costs.

[0005] A method for optimizing energy storage configuration taking into account new energy, power grid and user capacity sharing comprises the following steps:

[0006] Step 1: Build a new energy-grid-user-side energy storage configuration model;

[0007] Step 2: Build a new energy-grid-user-side energy storage sharing strategy;

[0008] Step 3: Based on the energy storage configuration model and energy storage sharing strategy, establish an energy storage optimization scheduling model for new energy, power grid and user side.

[0009] The energy storage configuration model for the new energy side is constructed as follows:

[0010] In order to achieve the goal of smoothing the grid-connected power fluctuation, the energy storage system is reasonably configured in the new energy station. The actual grid-connected power of the new energy station is the sum of the total output of the new energy station and the output of the configured energy storage system. It must also meet the requirements that the actual grid-connected power fluctuation of the new energy does not exceed 1 / 10 of the installed capacity in 1 minute and does not exceed 1 / 3 of the installed capacity in 10 minutes. The mathematical model of the actual grid-connected power is:

[0011]

[0012] Where: P x,i (t) is the actual grid-connected power of the new energy station i in period t; P w,i (t) is the output power of the new energy station i in period t; The energy storage system configured for the new energy station i is to smooth out the output of the new energy power fluctuation during the t period; The energy storage system configured for the new energy station i is the charging and discharging power in the t period to smooth out the fluctuation of the new energy power; is the energy storage charging and discharging state; N is the number of new energy stations; T is the statistical period;

[0013] The power fluctuation rate of the new energy station grid-connected can be expressed as:

[0014] P x,i (t)-P x,i (t-Δt)|≤λ i Δt (3)

[0015]

[0016] Where: i Δt is the upper limit of the grid power fluctuation allowed for the new energy station i within the inspection window of duration Δt; The upper limit of 1-minute volatility; is the upper limit of 1-min volatility; P Ni It is the installed capacity of new energy station i.

[0017] The energy storage configuration model on the grid side is constructed as follows:

[0018] Energy storage is configured on the grid side. The dual characteristics of energy storage power supply and load are utilized to charge during the period of high-energy generation and discharge during the peak load period, so as to achieve the purpose of peak load reduction and valley filling and improve the consumption rate of new energy. At the same time, grid-side energy storage can also obtain price arbitrage through "low storage and high generation";

[0019] The energy storage configuration model on the grid side is as follows:

[0020] 1) Reduce the penalty income for abandoning wind and solar power

[0021] The penalty cost of abandoned wind and solar power in the power grid is expressed as follows:

[0022]

[0023] Where: C g P is the penalty cost of wind and solar power abandonment in the power grid during the statistical time T; y,i(t), P x,i (t) is the predicted grid-connected power and actual grid-connected power of the new energy station i in period t; μ g Penalize the unit price for abandoning wind and solar;

[0024] After configuring energy storage, the operating benefits of the grid in reducing wind and solar power abandonment penalties within the statistical time T are as follows:

[0025]

[0026] Where: and They represent the penalty costs of abandoning wind and solar power before and after the grid is equipped with energy storage;

[0027] 2) Operational benefits of auxiliary thermal power peak regulation

[0028] During the statistical period T, the operating benefits brought to the power grid by energy storage-assisted thermal power peak regulation are expressed as follows:

[0029]

[0030] Where: are the costs of the ith thermal power unit participating in peak load regulation in period t before and after energy storage configuration; M is the number of thermal power units;

[0031] 3) Peak-to-valley arbitrage benefits

[0032] The operating income of the power grid using energy storage to carry out "low storage and high generation" arbitrage within the statistical time T is expressed as follows:

[0033]

[0034] Where: are the discharge and charging power of the grid-side energy storage during period t; η w , η v They are peak-time electricity prices and valley-time electricity prices respectively.

[0035] The energy storage optimization configuration model on the user side is constructed as follows:

[0036] User-side energy storage uses the "low storage, high generation" method of charging at low prices during off-peak hours and discharging at high prices during peak hours to conduct price arbitrage during the operation phase.

[0037] 1) Operating income of “low-storage, high-production” arbitrage

[0038] User-side energy storage can shift loads and achieve load peak shaving and valley filling. In a time-of-use electricity price market environment, the energy storage system is controlled to charge during low load periods and discharge during peak load periods, thereby realizing arbitrage income by utilizing the peak-valley electricity price difference. The arbitrage income within the statistical time T is expressed as:

[0039]

[0040] Where: are the discharge and charging power of the energy storage configured for user i in period t; J is the number of users who configure energy storage;

[0041] 2) Government electricity price subsidy income

[0042] The user-side energy storage subsidy income within the statistical time T is:

[0043]

[0044] Where: P e It is the government that subsidizes the electricity price; The discharge state of the energy storage during period t.

[0045] Step 2:

[0046] Design a new energy-grid-user-side energy storage capacity sharing strategy based on the sharing model of new energy, users and grid-side energy storage;

[0047] (1) One-way energy storage sharing strategy

[0048] The sharing mode of energy storage on the new energy side is to share the remaining capacity with the grid side in a one-way manner after achieving the goal of smoothing the fluctuation of new energy output on this side. The new energy storage sharing model is:

[0049]

[0050] Where: The shared energy storage output power of the new energy station i in period t; is the actual output power of the energy storage system of the new energy station i in period t; is the actual charging and discharging power of the energy storage system at the new energy station i during period t;

[0051] (2) Energy storage two-way sharing strategy

[0052] 1) Grid side - user side

[0053] During the period when the renewable energy side energy storage is not shared with the grid, the grid side energy storage will consider sharing its own surplus energy storage capacity with users:

[0054]

[0055] Where: The energy storage output power that meets the grid-side regulation requirements during period t; The shared energy storage output power on the grid side during period t; is the actual output power of the energy storage system on the grid side during period t; are the actual charging and discharging power of the energy storage system in period t on the grid side respectively; They are energy storage charging and discharging states respectively;

[0056] 2) User side - grid side

[0057] User-side energy storage can only be shared with the grid side, not with the renewable energy side:

[0058]

[0059] Where: The energy storage output power that meets the regulation needs of user i during period t; Share the energy storage output power for user i in period t; The actual output power of the energy storage system for user i in period t; The actual charging and discharging power of the energy storage system for user i in period t.

[0060] The objective function of the energy storage optimization scheduling model of new energy-grid-user side is:

[0061] Considering the impact of charge and discharge depth and charge and discharge times on the service life of energy storage, the objective function of the new energy side energy storage optimization scheduling model with the goal of minimizing the sum of the absolute values ​​of the energy storage output power of the new energy station i in each period within the statistical time T is:

[0062]

[0063] The objective function of the grid-side energy storage optimization dispatch model with the goal of maximizing the net profit of grid operation is:

[0064]

[0065] Where: are the energy storage charging and discharging power that meets the grid-side energy storage demand during period t; η is the unit price of energy storage operation and maintenance cost;

[0066] The objective function of the user-side energy storage optimization dispatch model with the goal of maximizing the user's net operating profit is:

[0067]

[0068] Where: They are respectively the energy storage charging and discharging power that meets the user-side energy storage demand during period t.

[0069] The operating constraints of the energy storage optimization dispatch model on the new energy-grid-user side are:

[0070] 1) Operation constraints on new energy side

[0071] Constraints on abandoned electricity from new energy sources:

[0072]

[0073] Where: β is the proportion of renewable energy abandoned in the power grid; β max The maximum proportion of power abandoned by renewable energy in the power grid;

[0074] Energy storage constraints:

[0075]

[0076] Where: is the rated output of the new energy station i; is the energy storage rated power of the new energy station i; is the energy storage charge state of the new energy station i at time t; They represent the upper and lower limits of the energy storage charge state of the new energy station i respectively; Indicates the initial value, end value and set value of the energy storage charge state of the new energy station i, is the energy storage charging and discharging efficiency of new energy station i; is the energy storage capacity of new energy station i at time t; is the rated capacity of energy storage at the new energy station i;

[0077] 2) Grid-side operation constraints

[0078] Thermal power unit operation constraints:

[0079]

[0080] Where: P i G (t) is the output of the i-th thermal power unit at time t; are the minimum and maximum output of the i-th thermal power unit respectively; P i G,down , P i G,up are the maximum downward climbing amount and the maximum upward climbing amount of the i-th thermal power unit respectively;

[0081] Energy storage constraints:

[0082]

[0083] Where: The rated power of grid energy storage; SOC G (t) the energy storage charge state of the grid at time t; Respectively represent the upper and lower limits of the grid energy storage charge state; SOC G (0) SOC G (T) They represent the initial value, end value and set value of the grid energy storage charge state respectively. E is the charging and discharging efficiency of grid energy storage;G (t) is the energy storage capacity of the power grid at time t; Rated capacity of energy storage for the grid;

[0084] 3) User-side operation constraints

[0085] Grid power balance constraints:

[0086]

[0087] Where: is the grid load during period t; P TIE (t) is the power of the grid tie line in period t, which is positive if it is received and negative if it is not received;

[0088] Energy storage constraints:

[0089]

[0090] Where: is the energy storage rated power of user i; Energy storage charge state of user i at time t; Respectively represent the upper and lower limits of the energy storage charge state of user i; Indicates the initial value, end value and set value of the energy storage charge state of user i; is the energy storage charging and discharging efficiency of user i; is the energy storage capacity of user i at time t; The rated capacity of energy storage for user i.

[0091] The present invention considers the "source-load" dual characteristics and rapid response capabilities of the energy storage system, and plans to configure energy storage systems on the three sides of new energy, power grid and users, and achieves the purpose of smoothing the fluctuation of new energy output, alleviating the peak-shaving pressure of thermal power units, and smoothing the system load by sharing the energy storage capacity on the three sides. The specific advantages are as follows: 1) Reduce the number of access to reactive compensation equipment, thereby reducing unnecessary communication time, regulation costs, and equipment access investment costs; 2) Alleviate the problem of reduced resource utilization due to the reduction of new energy output, and ensure the benefits of electricity users; 3) By configuring energy storage on the power generation side, it is possible to effectively solve the problems of output fluctuation smoothing, tracking power generation plans, reducing forecast errors, and reducing wind or solar power abandonment. 4) Three-side energy storage sharing is to multiplex energy storage resources in time and space, integrate the different energy storage needs of multiple participants, and use the time and space complementary characteristics of demand to achieve efficient utilization of energy storage resources and renewable energy. DETAILED DESCRIPTION

[0092] In order to make the implementation and advantages of the technical method of the present invention clear, the implementation process is described in detail.

[0093] A method for optimizing energy storage configuration taking into account the sharing of new energy, power grid and user capacity is implemented in the following steps:

[0094] Step 1: New energy-grid-user-side energy storage optimization configuration model

[0095] (1) Energy storage configuration on the new energy side

[0096] The power fluctuation of the new energy station must meet certain limits, that is, the power fluctuation of the new energy station i in the inspection window of duration Δt must meet certain constraints. The national standard GB / T 19963.1-2021 "Technical Regulations for Wind Farm Access to Power System Part 1: Onshore Wind Power" stipulates that the 1-minute fluctuation of the grid-connected power shall not exceed 1 / 10 of the installed capacity of wind power, and the 10-minute fluctuation shall not exceed 1 / 3 of the installed capacity of wind power. The national standard GB / T 19964-2011 "Technical Regulations for Photovoltaic Power Station Access to Power System" stipulates that the 1-minute fluctuation of the grid-connected power shall not exceed 1 / 10 of the installed capacity of the photovoltaic power station, and the 10-minute fluctuation shall not exceed 1 / 3 of the installed capacity of the photovoltaic power station. See Table 1 and Table 2 for details.

[0097] Table 1 Active power change limits of wind farms

[0098]

[0099] Table 2 Active power change limits of photovoltaic power stations

[0100]

[0101] By reasonably configuring the energy storage system at the new energy station to achieve the purpose of smoothing the grid-connected power fluctuation, at this time, the actual grid-connected power of the new energy station is the sum of the total output of the new energy station and the output of the configured energy storage system. The mathematical model of the actual grid-connected power is:

[0102]

[0103] Where: P x,i (t) is the actual grid-connected power of the new energy station i in period t; P w,i (t) is the output power of the new energy station i in period t; The energy storage system configured for the new energy station i is to smooth out the output of the new energy power fluctuation during the t period; The energy storage system configured for the new energy station i is the charging and discharging power in the t period to smooth out the fluctuation of the new energy power; is the energy storage charging and discharging status; N is the number of new energy stations; T is the statistical period.

[0104] The power fluctuation rate of the new energy station grid-connected can be expressed as:

[0105] Px,i (t)-P x,i (t-Δt)|≤λ i Δt (3)

[0106]

[0107] Where: i Δt is the upper limit of the grid power fluctuation allowed for the new energy station i within the inspection window of duration Δt; The upper limit of 1-minute volatility; is the upper limit of 1-min volatility; P Ni It is the installed capacity of new energy station i.

[0108] (2) Energy storage configuration on the grid side

[0109] Energy storage is configured on the grid side, and the dual characteristics of power supply and load are utilized to charge during the period of high-energy generation of new energy and discharge during the peak load period, so as to achieve the purpose of peak load reduction and valley filling and improve the consumption rate of new energy. At the same time, energy storage on the grid side can also obtain price arbitrage through "low storage and high generation". The configuration model of energy storage on the grid side is as follows:

[0110] 1) Reduce the penalty income for abandoning wind and solar power

[0111] The penalty cost of abandoned wind and solar power in the power grid is expressed as follows:

[0112]

[0113] Where: C g is the penalty cost of wind and solar power abandonment in the statistical time T; y,i (t), P x,i (t) is the predicted grid-connected power and actual grid-connected power of the new energy station i in period t; μ g Penalty unit price for abandoning wind power.

[0114] After configuring energy storage, the operating benefits of the grid in reducing wind and solar power abandonment penalties within the statistical time T are as follows:

[0115]

[0116] Where: and They respectively represent the penalty costs for abandoning wind and solar power before and after the grid is configured with energy storage.

[0117] 2) Operational benefits of auxiliary thermal power peak regulation

[0118] During the statistical period T, the operating benefits brought to the power grid by energy storage-assisted thermal power peak regulation are expressed as follows:

[0119]

[0120] Where: are the costs of the ith thermal power unit participating in peak load regulation in period t before and after energy storage configuration; M is the number of thermal power units.

[0121] 3) Peak-to-valley arbitrage benefits

[0122] The operating income of the power grid using energy storage to carry out "low storage and high generation" arbitrage within the statistical time T is expressed as follows:

[0123]

[0124] Where: are the discharge and charging power of the grid-side energy storage during period t; η w , η v They are peak-time electricity prices and valley-time electricity prices respectively.

[0125] (3) User-side energy storage configuration

[0126] User-side energy storage mainly conducts price arbitrage during the operation phase through the "low storage and high generation" form of low-price charging during valley hours and high-price discharging during peak hours.

[0127] 1) Operating income of “low-storage, high-production” arbitrage

[0128] User-side energy storage can shift loads and achieve load peak shaving and valley filling. In a time-of-use electricity price market, the energy storage system is controlled to charge when the load is low and discharge when the load is peak, and arbitrage income is achieved by using the peak-valley electricity price difference. The arbitrage income within the statistical time T is expressed as:

[0129]

[0130] Where: are the discharge and charging powers of the energy storage configured for user i in period t; J is the number of users who have configured energy storage.

[0131] 2) Government electricity price subsidy income

[0132] At present, the cost of energy storage is relatively high. The government's industrial support and economic subsidies have a significant effect on promoting the development of energy storage. The owner unit is subsidized 0.3 yuan per kW·h of power generation (discharge). The user-side energy storage subsidy income within the statistical time T is:

[0133]

[0134] Where: P e It is the government that subsidizes the electricity price; The discharge state of the energy storage during period t.

[0135] Step 2: New energy-grid-user-side energy storage sharing strategy

[0136] In the case where energy storage is configured on all three sides of new energy, power grid and user, if the rapid response characteristics and source-load characteristics of energy storage are fully utilized during operation, and energy storage sharing on the three sides is achieved while meeting the energy storage needs of this side, it can greatly reduce the redundant configuration of energy storage in the system, reduce the energy storage configuration cost, and improve the unit utilization efficiency and benefits of energy storage. Therefore, the present invention designs a new energy-grid-user side energy storage capacity sharing strategy based on the mode of energy storage participation in sharing by new energy, users and power grid side.

[0137] (1) One-way energy storage sharing strategy

[0138] The energy storage between the new energy station and the grid side is a one-way sharing between the new energy station and the grid side. The sharing strategy is that the new energy station provides its surplus energy storage capacity to the grid side when its own grid-connected power fluctuation meets the national standards, thereby increasing the regulation capacity of the grid side. The grid-side energy storage cannot smooth out the output fluctuation of the new energy station grid connection point without changing the new energy power generation capacity, because the power transmission from the grid side to the new energy side will cause power backflow and affect the power quality of the grid. Therefore, the sharing mode of energy storage on the new energy side is to share the remaining capacity with the grid in a one-way manner after completing the goal of smoothing the output fluctuation of new energy on this side.

[0139] The new energy storage sharing model is:

[0140]

[0141] Where: The shared energy storage output power of the new energy station i in period t; is the actual output power of the energy storage system of the new energy station i in period t; is the actual charging and discharging power of the energy storage system at the new energy station i during period t;

[0142] (2) Energy storage two-way sharing strategy

[0143] 1) Grid side - user side

[0144] The main purpose of configuring energy storage on the grid side is to improve the level of new energy consumption and reduce the system peak regulation cost. After completing the above two regulation tasks, the surplus energy storage on the grid side can be shared with the outside. And the regulations are as follows: During the period when the energy storage on the new energy side is not shared with the grid, the grid side energy storage will consider sharing its surplus energy storage capacity with users.

[0145]

[0146] Where: The energy storage output power that meets the grid-side regulation requirements during period t; The shared energy storage output power on the grid side during period t; is the actual output power of the energy storage system on the grid side during period t; are the actual charging and discharging power of the energy storage system in period t on the grid side respectively; They are energy storage charging and discharging states respectively.

[0147] 2) User side - grid side

[0148] The main purpose of users installing energy storage is to reduce electricity costs. Therefore, user-side energy storage should share surplus capacity with the grid after completing the regulation task on this side. And the regulations are as follows: user-side energy storage can only be shared with the grid side, not with the new energy side.

[0149]

[0150] Where: The energy storage output power that meets the regulation needs of user i during period t; Share the energy storage output power for user i in period t; is the actual output power of the energy storage system for user i in period t. The actual charging and discharging power of the energy storage system for user i in period t.

[0151] Step 3: Establishment of new energy-grid-user side optimization dispatch model

[0152] Based on the energy storage configuration model and energy storage sharing strategy, establish an energy storage optimization scheduling model for new energy, power grid and user side;

[0153] The objective function of the energy storage optimization scheduling model of new energy-grid-user side is:

[0154] Energy storage on the new energy side must first meet the needs of smoothing the fluctuation of new energy output, and then consider external sharing of energy storage. The present invention considers the impact of the depth of charge and discharge and the number of charge and discharge times on the service life of energy storage, and takes the minimum sum of the absolute values ​​of the output power of energy storage at the new energy station i in each period within the statistical time T as the energy storage optimization scheduling target.

[0155]

[0156] The main purpose of installing energy storage on the grid side is to improve the level of new energy consumption and reduce the system peak load cost. Therefore, a grid-side energy storage optimization dispatching model is established with the goal of maximizing the net profit of grid operation.

[0157]

[0158] Where: are the energy storage charging and discharging powers that meet the grid-side energy storage needs during period t; η is the unit price of energy storage operation and maintenance cost.

[0159] The main purpose of users installing energy storage is to reduce electricity costs. Therefore, user-side energy storage should share surplus capacity with the grid after completing the regulation task on that side. Therefore, a user-side energy storage optimization scheduling model is established with the goal of maximizing the net profit of user operation.

[0160]

[0161] Where: They are respectively the energy storage charging and discharging power that meets the user-side energy storage demand during period t.

[0162] The operating constraints of the energy storage optimization dispatch model on the new energy-grid-user side are:

[0163] 1) Operation constraints on new energy side

[0164] Constraints on abandoned electricity from new energy sources:

[0165]

[0166] Where: β is the proportion of renewable energy abandoned in the power grid; β max It is the maximum proportion of power abandoned by renewable energy in the power grid.

[0167] Energy storage constraints:

[0168]

[0169] Where: is the rated output of the new energy station i; is the energy storage rated power of the new energy station i; is the energy storage charge state of the new energy station i at time t; They represent the upper and lower limits of the energy storage charge state of the new energy station i respectively; It represents the initial value, end value and set value of the energy storage charge state of the new energy station i. is the energy storage charging and discharging efficiency of new energy station i; is the energy storage capacity of new energy station i at time t; is the rated capacity of energy storage at new energy station i.

[0170] 2) Grid-side operation constraints

[0171] Thermal power unit operation constraints:

[0172]

[0173] Where: P i G (t) is the output of the i-th thermal power unit at time t; are the minimum and maximum output of the i-th thermal power unit respectively; Pi G,down , P i G,up are the maximum downward climbing amount and the maximum upward climbing amount of the i-th thermal power unit respectively.

[0174] Energy storage constraints:

[0175]

[0176] Where: The rated power of grid energy storage; SOC G (t) the energy storage charge state of the grid at time t; Respectively represent the upper and lower limits of the grid energy storage charge state; SOC G (0) SOC G (T) They respectively represent the initial value, end value and set value of the grid energy storage charge state. E is the charging and discharging efficiency of grid energy storage; G (t) is the energy storage capacity of the power grid at time t; It is the rated capacity of grid energy storage.

[0177] 3) User-side operation constraints

[0178] Grid power balance constraints:

[0179]

[0180] Where: is the grid load during period t; P TIE (t) is the power of the grid interconnection line in time period t, which is positive if input and negative if not.

[0181] Energy storage constraints:

[0182]

[0183] Where: is the energy storage rated power of user i; Energy storage charge state of user i at time t; Respectively represent the upper and lower limits of the energy storage charge state of user i; Indicates the initial value, end value and set value of the energy storage charge state of user i. is the energy storage charging and discharging efficiency of user i; is the energy storage capacity of user i at time t; The rated capacity of energy storage for user i.

Claims

1. A method for optimizing energy storage configuration taking into account new energy, power grid and user capacity sharing, characterized in that: The following steps are involved: Step 1: Build a new energy-grid-user-side energy storage configuration model; Step 2: Build a new energy-grid-user-side energy storage sharing strategy; Step 3: Based on the energy storage configuration model and energy storage sharing strategy, establish an energy storage optimization scheduling model for new energy, power grid and user side.

2. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: The energy storage configuration model for the new energy side is constructed as follows: In order to achieve the goal of smoothing the grid-connected power fluctuation, the energy storage system is reasonably configured in the new energy station. The actual grid-connected power of the new energy station is the sum of the total output of the new energy station and the output of the configured energy storage system. It must also meet the requirements that the actual grid-connected power fluctuation of the new energy does not exceed 1 / 10 of the installed capacity in 1 minute and does not exceed 1 / 3 of the installed capacity in 10 minutes. The mathematical model of the actual grid-connected power is: Where: P x,i (t) is the actual grid-connected power of the new energy station i in period t; P w,i (t) is the output power of the new energy station i in period t; The energy storage system configured for the new energy station i is to smooth out the output of the new energy power fluctuation during the t period; The energy storage system configured for the new energy station i is the charging and discharging power in the t period to smooth out the fluctuation of the new energy power; is the energy storage charging and discharging state; N is the number of new energy stations; T is the statistical period; The power fluctuation rate of the new energy station grid-connected can be expressed as: P x,i (t)-P x,i (t-Δt)|≤λ i Δt (3) Where: i Δt is the upper limit of the grid power fluctuation allowed for the new energy station i within the inspection window of duration Δt; The upper limit of 1-minute volatility; is the upper limit of 1-min volatility; P Ni It is the installed capacity of new energy station i.

3. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: The energy storage configuration model on the grid side is constructed as follows: Energy storage is configured on the grid side. The dual characteristics of energy storage power supply and load are utilized to charge during the period of high generation of new energy and discharge during the peak load period, so as to achieve the purpose of peak load reduction and valley filling and improve the consumption rate of new energy. At the same time, grid-side energy storage can also obtain price arbitrage through "low storage and high generation"; The energy storage configuration model on the grid side is as follows: 1) Reduce the penalty income for abandoning wind and solar power The penalty cost of abandoned wind and solar power in the power grid is expressed as follows: Where: C g P is the penalty cost of wind and solar power abandonment in the power grid during the statistical time T; y,i (t), P x,i (t) is the predicted grid-connected power and actual grid-connected power of the new energy station i in period t; μ g Penalize the unit price for abandoning wind and solar; After configuring energy storage, the operating benefits of the grid in reducing wind and solar power abandonment penalties within the statistical time T are as follows: Where: and They represent the penalty costs of abandoning wind and solar power before and after the grid is equipped with energy storage; 2) Operational benefits of auxiliary thermal power peak regulation During the statistical period T, the operating benefits brought to the power grid by energy storage-assisted thermal power peak regulation are expressed as follows: Where: are the costs of the ith thermal power unit participating in peak load regulation in period t before and after energy storage configuration; M is the number of thermal power units; 3) Peak-to-valley arbitrage benefits The operating income of the power grid using energy storage to carry out "low storage and high generation" arbitrage within the statistical time T is expressed as follows: Where: are the discharge and charging power of the grid-side energy storage during period t; η w , η v They are peak-time electricity prices and valley-time electricity prices respectively.

4. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: The energy storage optimization configuration model on the user side is constructed as follows: User-side energy storage uses the "low storage, high generation" method of charging at low prices during off-peak hours and discharging at high prices during peak hours to achieve price arbitrage during the operation phase. 1) Operating income of "low storage and high issuance" arbitrage User-side energy storage can shift loads and achieve load peak shaving and valley filling. In a time-of-use electricity price market environment, the energy storage system is controlled to charge during low load periods and discharge during peak load periods, thereby realizing arbitrage income by utilizing the peak-valley electricity price difference. The arbitrage income within the statistical time T is expressed as: Where: are the discharge and charging power of the energy storage configured for user i in period t; J is the number of users who configure energy storage; 2) Government electricity price subsidy income The user-side energy storage subsidy income within the statistical time T is: Where: P e It is the government that subsidizes the electricity price; The discharge state of the energy storage during period t.

5. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: Step 2: Design a new energy-grid-user-side energy storage capacity sharing strategy based on the sharing model of new energy, users and grid-side energy storage; (1) One-way energy storage sharing strategy The sharing mode of energy storage on the new energy side is to share the remaining capacity with the grid side in a one-way manner after achieving the goal of smoothing the fluctuation of new energy output on this side. The new energy storage sharing model is: Where: The shared energy storage output power of the new energy station i in period t; is the actual output power of the energy storage system of the new energy station i in period t; is the actual charging and discharging power of the energy storage system at the new energy station i during period t; (2) Energy storage two-way sharing strategy 1) Grid side - user side During the period when the renewable energy side energy storage is not shared with the grid, the grid side energy storage will consider sharing its own surplus energy storage capacity with users: Where: The energy storage output power that meets the grid-side regulation requirements during period t; The shared energy storage output power on the grid side during period t; is the actual output power of the energy storage system on the grid side during period t; are the actual charging and discharging power of the energy storage system in period t on the grid side respectively; They are energy storage charging and discharging states respectively; 2) User side - grid side User-side energy storage can only be shared with the grid side, not with the renewable energy side: Where: The energy storage output power that meets the regulation needs of user i during period t; Share the energy storage output power for user i in period t; The actual output power of the energy storage system for user i in period t; The actual charging and discharging power of the energy storage system for user i in period t.

6. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: The objective function of the energy storage optimization scheduling model of new energy-grid-user side is: Considering the impact of charge and discharge depth and charge and discharge times on the service life of energy storage, the objective function of the new energy side energy storage optimization scheduling model with the goal of minimizing the sum of the absolute values ​​of the energy storage output power of the new energy station i in each period within the statistical time T is: The objective function of the grid-side energy storage optimization dispatch model with the goal of maximizing the net profit of grid operation is: Where: are the energy storage charging and discharging power that meets the grid-side energy storage demand during period t; η is the unit price of energy storage operation and maintenance cost; The objective function of the user-side energy storage optimization dispatch model with the goal of maximizing the user's net operating profit is: Where: They are respectively the energy storage charging and discharging power that meets the user-side energy storage demand during period t.

7. The energy storage optimization configuration method considering new energy, power grid and user capacity sharing according to claim 1, characterized in that: The operating constraints of the energy storage optimization dispatch model on the new energy-grid-user side are: 1) Operation constraints on new energy side Constraints on abandoned electricity from new energy sources: Where: β is the proportion of renewable energy abandoned in the power grid; β max The maximum proportion of power abandoned by renewable energy in the power grid; Energy storage constraints: Where: is the rated output of the new energy station i; is the energy storage rated power of the new energy station i; is the energy storage charge state of the new energy station i at time t; They represent the upper and lower limits of the energy storage charge state of the new energy station i respectively; Indicates the initial value, end value and set value of the energy storage charge state of the new energy station i, is the energy storage charging and discharging efficiency of new energy station i; is the energy storage capacity of new energy station i at time t; is the rated capacity of energy storage at the new energy station i; 2) Grid-side operation constraints Thermal power unit operation constraints: Where: P i G (t) is the output of the i-th thermal power unit at time t; are the minimum and maximum output of the i-th thermal power unit respectively; P i G,down , P i G,up are the maximum downward climbing amount and the maximum upward climbing amount of the i-th thermal power unit respectively; Energy storage constraints: Where: The rated power of grid energy storage; SOC G (t) the energy storage charge state of the grid at time t; Respectively represent the upper and lower limits of the grid energy storage charge state; SOC G (0) SOC G (T) They represent the initial value, end value and set value of the grid energy storage charge state respectively. E is the charging and discharging efficiency of grid energy storage; G (t) is the energy storage capacity of the power grid at time t; Rated capacity of energy storage for the grid; 3) User-side operation constraints Grid power balance constraints: Where: is the grid load during period t; P TIE (t) is the power of the grid tie line in period t, which is positive if it is received and negative if it is not received; Energy storage constraints: Where: is the energy storage rated power of user i; Energy storage charge state of user i at time t; Respectively represent the upper and lower limits of the energy storage charge state of user i; Indicates the initial value, end value and set value of the energy storage charge state of user i; is the energy storage charging and discharging efficiency of user i; is the energy storage capacity of user i at time t; The rated capacity of energy storage for user i.

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