Energy storage and new energy collaborative planning "equal area rule" method

Abstract

The application discloses a kind of energy storage and new energy collaborative planning " equal-area rule " method, this method is based on new energy consumption characteristics, establishes " equal-area rule " model to carry out energy storage configuration, accurately connects energy storage capacity with new energy consumption capacity, realizes the optimal configuration of energy storage under the given new energy consumption target, by guaranteeing the number of hours, energy storage is included in power grid reserve and balance, obtains the whole set of parameters such as energy storage peak power, energy storage time length and annual utilization hours under different new energy consumption capacity scenarios.

Description

Technical Field

[0001] This invention belongs to the field of new power system energy storage and power planning technology, and relates to a "equal area rule" method for coordinated planning of energy storage and new energy. Background Technology

[0002] On the one hand, due to the randomness, volatility, and unpredictability of new energy sources, large-scale grid connection requires the power system to have flexible and rapid response capabilities, adapting to the uncertainties of new energy power generation. On the other hand, there is a mutual constraint similar to the "Krugman impossibility triangle" between the installed capacity, utilization rate, and power generation share of new energy sources. For example, increasing the installed capacity increases the proportion of new energy power generation but decreases the utilization rate. This requires the power system to achieve "balance between abundant and scarce" new energy resources and "simultaneous increase in both quantity and rate" of new energy utilization through "energy transfer." Energy storage can realize "energy transfer" in power systems with a high proportion of new energy sources, while improving the system's flexible adjustment capabilities. It is an effective means to promote the efficient utilization of new energy sources in new power systems.

[0003] Currently, energy storage planning and configuration methods mainly fall into two categories: One type uses energy storage capacity calculated based on typical methods and scenarios to reflect the annual energy storage configuration demand. This method can meet the energy storage demand in most scenarios throughout the year, but it cannot reflect the optimal energy storage configuration for high-proportion renewable energy systems, nor can it reflect the energy storage demand when renewable energy resources are extremely scarce. The energy storage capacity may be over- or under-allocated. The other type uses time-series production simulation to calculate the energy storage configuration capacity to meet predetermined goals multiple times, and this is currently the most widely used method. This method reflects the energy storage demand under specific goals, but it fails to fully utilize the inherent characteristics of renewable energy sources. It often determines the energy storage capacity through multiple, tentative simulations, lacking a theoretical basis. Summary of the Invention

[0004] The purpose of this invention is to provide a "rule of equal area" method for the coordinated planning of energy storage and new energy. This method solves the problems of the current energy storage planning lacking mathematical basis, capacity over-allocation or under-allocation, and overly complicated calculation process. For the first time, it achieves the goals of energy storage replacing thermal power generation, deep coupling of energy storage and new energy consumption, and coordinated planning.

[0005] The technical solution adopted in this invention is the "equal area rule" method for the coordinated planning of energy storage and new energy sources, which is implemented according to the following steps:

[0006] Step 1: Analyze the grid balance including new energy sources to obtain the per-unit value of new energy absorption capacity x and the proportion of new energy power generation R;

[0007] Step 2: Analyze the theoretical power sequence of new energy sources, and calculate the characteristic curve of new energy absorption capacity and the guarantee hours of new energy range according to the per-unit value x of new energy absorption capacity obtained in Step 1.

[0008] Step 3: Based on the new energy consumption curve obtained in Step 2, the "equal area rule" is proposed according to the two sets of power increase sequences to determine the energy storage capacity and peak power, and the energy storage is included in the balance according to different guarantee rate ranges.

[0009] Step 4: Determine the upper limit of new energy absorption capacity based on the new energy target utilization rate and the absorption curve in Step 2. Iterate through the lower limit of new energy absorption capacity. For each absorption interval determined by the upper and lower limits of absorption capacity, use the "equal area rule" in Step 3 to calculate the energy storage capacity, peak power, energy storage duration and new energy installed capacity corresponding to each absorption capacity interval, and form a set of calculation results.

[0010] Step 5: Based on the boundary conditions of grid balance in the planning year, classify and discuss the known and unknown situations of new energy installed capacity, and determine the energy storage configuration parameters for the planning year from the result set of Step 4 based on the scenario extraction method.

[0011] The invention is further characterized by:

[0012] Step 1 is as follows:

[0013] Step 1.1, New Energy Absorption Capacity P S For the system's power generation load P L Subtract the minimum output P of the conventional unit T,min As shown in the following formula:

[0014] P S =P L -P T,min (1);

[0015] Conventional unit operating capacity P T,max The maximum power generation load P of the system L,max The maximum load is calculated using the reserve rate α and the average load P. L,mean Dividing by the load factor ε, the minimum technical output of a conventional unit is determined by the operating capacity and the peak shaving rate β, as shown in the following formula:

[0016]

[0017] For the space P S The energy E in the storage space is obtained by integration. S This is also equal to the average renewable energy absorption capacity P. S,mean The product of the statistical period T and the load P L The total power generation E can be obtained by integration. L It is also equal to the average power generation load P L,mean The product of the product with the statistical period T is shown in the following formula:

[0018]

[0019] Further obtain the average renewable energy absorption capacity P S,mean As shown in the following formula:

[0020] P S,mean =P L,max ×[ε-(1+α)×(1-β)] (4);

[0021] Step 1.2, the per-unit value x of the renewable energy absorption capacity is the average renewable energy absorption capacity P. S,mean Divide by the installed capacity of new energy C, and define the installed capacity of new energy C and the maximum load P. L,max The ratio is the penetration rate ψ of new energy, and the per-unit value x of new energy absorption capacity can be obtained as shown in the following formula:

[0022]

[0023] E R Let T be the theoretical electricity output of new energy sources. R The proportion of new energy resources in the statistical period T is the new energy resource coefficient s, and the proportion of new energy power generation R can be obtained as shown in the following formula:

[0024]

[0025] Step 2 is as follows:

[0026] Step 2.1, standardize the theoretical power of new energy sources, specifically as follows:

[0027] The theoretical power of renewable energy sources in the power grid is collected over the entire year using time series data, and normalized using renewable energy installed capacity. In a time series of length M, the theoretical power P at time j is obtained. j Dividing by the installed capacity of new energy sources C yields the theoretical per-unit power value p. j As shown in the following formula:

[0028]

[0029] Step 2.2: Calculate the actual power and utilization rate of new energy sources;

[0030] Divide the installed capacity of new energy into m small intervals, and let i increase by 1 each time from 1 to m, x i The size of the i-th interval can also be considered as the per-unit value of the new energy absorption capacity obtained in step 1, compared with x. j With p j The theoretical power that does not exceed the absorption capacity is the actual power (W) of the new energy source. i,j As shown in the following formula:

[0031]

[0032] For the i-th installed capacity zone, the ratio of actual power integral energy to theoretical power integral energy is the renewable energy utilization rate η. i As shown in the following formula:

[0033]

[0034] Let i vary continuously between 1 and 100, then we obtain the renewable energy absorption capacity x for each group. i and the corresponding utilization rate η j , with x i η is the independent variable. j The relationship curve between the two variables is called the new energy consumption curve;

[0035] Step 2.3, calculate the number of hours for the new energy vehicle segment, specifically as follows:

[0036] Determine the target η for the utilization rate of new energy sources. * Using the absorption curve obtained in step 2, find the per-unit value x of the new energy absorption capacity corresponding to the target utilization rate. * Let x i 0 to x * Given any one of the two sets of new energy absorption capacities, under the above two sets of new energy absorption capacities... Respectively at time j and x * x i The power of renewable energy is hindered, where C is the installed capacity of renewable energy and N is the length of the daily theoretical power sequence of renewable energy. They are respectively The corresponding number of daily obstruction hours for new energy sources is shown in the following formula:

[0037]

[0038] With x i The lower limit, x * The upper limit is defined as a range of renewable energy absorption capacity, within which the theoretical power hours of renewable energy are ΔT. i This is called the new energy range hours, as shown in the following formula:

[0039]

[0040] Step 2.4, calculate the guaranteed hours for the new energy range, specifically:

[0041] The daily interval hour sequence for the whole year was obtained statistically, and then the sequence ΔT was obtained by arranging it in ascending order. i =[ΔT i,1 ,ΔT i,2 ,...,ΔT i,n ], where ΔTi,1 ≤ΔT i,2 ,...,≤T i,n Let n be the number of days in a calendar year. Given a probability r%, the hour quantiles for that interval are:

[0042] I i,r =max{floor[n×(1-r%)],1} (12);

[0043] Among them, I i,r Let be an integer, satisfying 1I i,r n, floor indicates rounding down according to quantile I i,r The index, from the interval hour number ascending sequence ΔT i Find the corresponding value in the range, which is the guaranteed number of hours for the interval corresponding to the r% probability. Indicates ΔT i China Super League The percentage of the number of elements in a given element out of the total number of elements is r%, also known as the guarantee rate.

[0044]

[0045] Step 2.5, divide the protected area, specifically as follows:

[0046] m represents the number of new energy installed capacity ranges in step 2.2. Let i increase by 1 from 1 to m each time. For each group, x i and x * The interval formed will x i As the lower limit of the interval, x * As the upper limit of the interval, the guaranteed hours for each interval are counted and sorted in ascending order to obtain an ascending sequence. in If there exists an integer k less than m that satisfies:

[0047]

[0048] Then it is called x is the number of critical guarantee hours for the interval corresponding to probability r%. k For the corresponding lower limit critical value of the new energy absorption capacity range, the sequence x in =[x1,x2,...,x k The set of lower limits of absorption capacity that meets the guarantee rate requirement of r% is called the guaranteed region, and the sequence x out =[x k+1 ,x k+2 ,...,x n The set of lower limits of absorption capacity when the guarantee rate r% cannot be met is called the guarantee rate violation region.

[0049] Step 3 specifically involves:

[0050] Step 3.1: Establish the "equal area rule" model to determine the energy storage capacity, specifically as follows:

[0051] Step 3.1.1, using step 2.2.1, yields two hourly ascending sequences:

[0052]

[0053] Step 3.1.2, let T be the number of hours in the converted energy storage capacity and the installed capacity of new energy sources. b T b =[T b,1 ,T b,2 ,...,T b,n Then we get the following two sets of areas:

[0054]

[0055] In the formula, "~" represents the curve fitted to the corresponding sequence with the set of calendar days n as the independent variable, and O + (τ A ,F2(τ A )) and O - (τ B ,F3(τ B )) are respectively The intersection point with the other two curves;

[0056] Let ΔS = |S1 - S2| represent the area difference, and set the target for the area difference as a minimum value Erro. ​​Let T... b from The interval is increased by step size μ until ΔS is less than the target deviation Erro, at which point T is reached. b Optimal conversion hours for energy storage Energy storage capacity for:

[0057]

[0058] The peak energy storage power, energy storage duration, and annual utilization hours are as follows:

[0059]

[0060] In the formula, P o This is the time series of theoretical new energy power corresponding to the day with the minimum ΔS. T is the annual throughput of energy storage converted into hours. R For annual resource hours of new energy;

[0061] Step 3.2, based on the guaranteed area in 2.2.3, when the absorption capacity xi ∈x in At that time, the guaranteed hours of renewable energy can be replaced by energy storage relocation to replace the start-up of conventional power sources. According to the renewable energy absorption capacity calculation method in step 1, the renewable energy installed capacity can be obtained as follows:

[0062]

[0063] In the formula, γ represents the overall energy storage charging and discharging efficiency, and T... P This represents the maximum duration of the peak load.

[0064] When the absorption capacity x i ∈x out hour, Since the value is 0, according to the calculation method for new energy absorption capacity in step 1, the installed capacity of new energy can be obtained as follows:

[0065]

[0066] Step 4 specifically involves: determining the upper limit of new energy absorption capacity based on the new energy target utilization rate and the absorption curve from Step 2, and iterating through the lower limit of new energy absorption capacity; using the "equal area rule" from Step 3, calculating the energy storage capacity, peak power, energy storage duration, and new energy installed capacity corresponding to each absorption capacity range, forming a set of calculation results.

[0067]

[0068] In the formula, To guarantee the number of hours in the interval, To replace thermal power generation capacity with energy storage For energy storage capacity, For energy storage peak power, For energy storage duration, The annual utilization hours of energy storage.

[0069] Step 5 specifically involves:

[0070] Step 5.1, when the planned annual installed capacity of new energy is known, is as follows:

[0071]

[0072] In the formula, For the maximum load of the system in the planned year, For load factor, For reserve rate, For conventional power supply peak regulation rate, Given known boundaries such as the installed capacity of new energy sources, This refers to the initial renewable energy absorption capacity determined in step 1;

[0073] Step 5.2, when the planned annual installed capacity of new energy is unknown, the obtained installed capacity of new energy is:

[0074]

[0075] In the formula, For the planned new energy installed capacity, determine the energy storage configuration parameters according to the result set in step 4.

[0076] The beneficial effects of this invention are as follows:

[0077] (1) This invention proposes new energy statistical characteristics such as “new energy consumption characteristic curve” and “new energy range guarantee hours”, establishes a power grid balance model containing new energy, realizes the close relationship between power grid balance and the operating characteristics of new energy itself, and reveals the mathematical basis of new energy consumption.

[0078] (2) This invention establishes the “equal area rule” model for energy storage configuration. By utilizing the statistical characteristics of new energy, it provides the optimal energy storage capacity configuration method to meet the needs of new energy consumption and obtains characteristic parameters such as peak energy storage power, energy storage duration and annual utilization hours. This can effectively avoid the problem of over- or under-configuration of capacity and achieve precise matching between energy storage configuration and new energy consumption capacity.

[0079] (3) This invention incorporates energy storage into the balance according to different guarantee rate ranges, realizing coordinated planning of energy storage capacity and new energy installed capacity. By adjusting the new energy absorption capacity, it provides result sets of energy storage capacity and new energy installed capacity under different absorption scenarios.

[0080] (4) Based on the boundary conditions of the grid balance in the planning year, this invention obtains the energy storage capacity and new energy installed capacity of the planning year from the energy storage result set through the scenario extraction method according to the two cases of known and unknown new energy installed capacity, which can be directly used for grid planning. Attached Figure Description

[0081] Figure 1 This is the overall flowchart of the "equal area rule" method for coordinated planning of energy storage and new energy in this invention;

[0082] Figure 2 This is the new energy absorption characteristic curve in the "equal area rule" method for coordinated planning of energy storage and new energy in this invention;

[0083] Figure 3 This is a diagram showing the calculation of the number of hours in the interval in the "equal area rule" method for coordinated planning of energy storage and new energy in this invention;

[0084] Figure 4 This is a diagram showing the calculation of guaranteed working hours in the "equal area rule" method for coordinated planning of energy storage and new energy sources in this invention.

[0085] Figure 5 This is a schematic diagram of the "equal area rule" principle in the "equal area rule" method for coordinated planning of energy storage and new energy in this invention;

[0086] Figure 6 This is a flowchart of energy storage configuration when the installed capacity of new energy is known in the "equal area rule" method for coordinated planning of energy storage and new energy in this invention.

[0087] Figure 7 This is a flowchart of the energy storage configuration process when the installed capacity of new energy is unknown in the "equal area rule" method for coordinated planning of energy storage and new energy in this invention. Detailed Implementation

[0088] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0089] This invention presents a method for coordinated planning of energy storage and new energy sources using the "equal area rule." This method yields the energy storage configuration capacity and peak power, and its process is as follows: Figure 1 As shown, the specific steps are as follows:

[0090] Step 1 involves conducting a power grid balance analysis including renewable energy sources to obtain mathematical analytical expressions for key indicators such as renewable energy absorption capacity. Specifically, Step 1 includes:

[0091] Analyze the balance relationship of a power grid containing renewable energy sources and calculate the renewable energy absorption capacity. Renewable energy power is the sum of wind power and photovoltaic power.

[0092] Step 1.1, New Energy Absorption Capacity P S For the system's power generation load P L Subtract the minimum output P of the conventional unit T,min As shown in the following formula:

[0093] P S =P L -P T,min (1);

[0094] Conventional unit operating capacity P T,max It can be determined by the system's maximum power generation load P L,max The maximum load is calculated using the average load P. (The calculation is based on the reserve rate α.) L,mean Dividing by the load factor ε, the minimum technical output of a conventional unit is determined by the operating capacity and the peak shaving rate β, as shown in the following formula:

[0095]

[0096] For the space P S The energy E that can be stored in the storage space can be obtained by integration. S This is also equal to the average renewable energy absorption capacity P. S,meanThe product of the annual time T and the load P. L The total power generation E can be obtained by integration. L It is also equal to the average power generation load P L,mean The product of the product with the statistical period T is shown in the following formula:

[0097]

[0098] Further obtain the average renewable energy absorption capacity P S,mean As shown in the following formula:

[0099] P S,mean =P L,max ×[ε-(1+α)×(1-β)] (4);

[0100] Step 1.2, the per-unit value x of the renewable energy absorption capacity is the average renewable energy absorption capacity P. S,mean Divide by the installed capacity of new energy C, and define the installed capacity of new energy C and the maximum load P. L,max The ratio is the penetration rate ψ of new energy, and the per-unit value x of new energy absorption capacity can be obtained as shown in the following formula:

[0101]

[0102] E R Let T be the theoretical electricity output of new energy sources. R The proportion of the annual calendar hours T is the new energy resource coefficient s, and the proportion of new energy power generation R can be obtained as shown in the following formula:

[0103]

[0104] Step 2 involves mining the theoretical power characteristics of new energy sources to obtain the new energy absorption characteristic curve, thus establishing the correlation between the new energy absorption capacity and characteristics established in Step 1. Different absorption capacities are used to construct new energy absorption intervals, and the variation patterns of theoretical new energy hours within these intervals are statistically analyzed. The guaranteed hours for each interval are then calculated based on confidence levels, and different guarantee rate intervals are defined. Specifically, Step 2 includes:

[0105] The theoretical power sequence of new energy sources is analyzed, and the characteristic curve of new energy absorption and the guaranteed hours of new energy range are calculated according to the per-unit value of new energy absorption capacity obtained in step 1.

[0106] Step 2.1: Standardize the theoretical power of new energy sources.

[0107] The theoretical power (power generation under unrestricted natural conditions) of new energy sources in the power grid is collected over the entire year and normalized using the installed capacity of new energy sources. In a sequence of length M, the theoretical power P at time j is... jDividing by the installed capacity of new energy sources C yields the theoretical per-unit power value p. j As shown in the following formula:

[0108]

[0109] Step 2.2: Calculate the actual power and utilization rate of new energy sources.

[0110] Divide the installed capacity of new energy into m small intervals, and let i increase by 1 each time from 1 to m.

[0111] x i The size of the i-th interval can also be considered as the per-unit value of the new energy absorption capacity obtained in step 1, compared with x. j With p j The theoretical power that does not exceed the absorption capacity is the actual power (W) of the new energy source. i,j As shown in the following formula:

[0112]

[0113] For the i-th installed capacity zone, the ratio of actual power integral energy to theoretical power integral energy is the renewable energy utilization rate η. i As shown in the following formula:

[0114]

[0115] Let i vary continuously between 1 and 100, then we can obtain the renewable energy absorption capacity x for each group. i and its corresponding utilization rate η j , with x i η is the independent variable. j As the dependent variable, the relationship curve between the two is called the new energy consumption curve, such as... Figure 2 As shown, this achieves a balance between the power grid containing new energy sources and the power generation patterns of the new energy sources themselves.

[0116] Step 2.3: Calculate the number of hours in the new energy range.

[0117] Determine the target η for the utilization rate of new energy sources. * The per-unit value x of the renewable energy absorption capacity corresponding to the target utilization rate can be found from the absorption curve obtained in step 2. * Let x i 0 to x * Any one of the two sets of new energy absorption capacities. Under the above two sets of new energy absorption capacities, Let J represent the power of renewable energy sources that are hindered at time j, C represent the installed capacity of renewable energy sources, and N represent the length of the daily theoretical power sequence of renewable energy sources. These represent the corresponding daily obstruction hours for new energy sources, as shown in the following formula:

[0118]

[0119] With x i The lower limit, x * The upper limit is defined as a range of renewable energy absorption capacity, within which the theoretical power hours of renewable energy are ΔT. i ,like Figure 3 As shown, the number of hours in the new energy range is represented by the following formula:

[0120]

[0121] Step 2.4: Calculate the guaranteed hours for the new energy range.

[0122] The daily interval hour sequence for the whole year was obtained statistically, and then the sequence ΔT was obtained by arranging it in ascending order. i =[ΔT i,1 ,ΔT i,2 ,...,ΔT i,n ], where ΔT i,1 ≤ΔT i,2 ,...,≤T i,n Let n be the number of days in a calendar year. Given a probability r%, the corresponding hour quantile is:

[0123] I i,r =max{floor[n×(1-r%)],1} (12);

[0124] Among them, I i,r Let be an integer, satisfying 1I i,r n, floor indicates rounding down, for example floor(0.95) = 0, floor(1.95) = 1. According to quantile I i,r The index, from the interval hour number ascending sequence ΔT i Find the corresponding value in the range, which is the guaranteed number of hours for the interval corresponding to the r% probability. Indicates ΔT i China Super League The percentage of elements in a given sequence relative to the total number of elements is r%, also known as the guarantee rate. For example... Figure 4 As shown, specifically:

[0125]

[0126] Step 2.5: Divide the protected area.

[0127] m represents the number of new energy installed capacity ranges in step 2.2. Let i increase by 1 from 1 to m each time. For each group, x i and x * The interval formed will xi As the lower limit of the interval, x * This serves as the upper limit of the interval. The guaranteed hours for each interval are counted and sorted in ascending order to obtain an ascending sequence. in If there exists an integer k less than m that satisfies:

[0128]

[0129] Then it is called x is the number of critical guarantee hours for the interval corresponding to probability r%. k This represents the lower limit of the corresponding renewable energy absorption capacity range. Sequence x in =[x1,x2,...,x k The set of lower limits of absorption capacity that meets the guarantee rate requirement of r% is called the guaranteed region. Sequence x out =[x k+1 ,x k+2 ,...,x n The set of lower limits of absorption capacity when the guarantee rate r% cannot be met is called the guarantee rate violation region.

[0130] Step 3: Based on the renewable energy absorption curve obtained in Step 2, given the upper and lower limits of renewable energy absorption capacity, determine the amount of renewable energy within the absorption range and the blocked amount exceeding the lower limit. Based on the two sets of energy increase sequences, propose the "equal area rule" to determine the calculation method for energy storage capacity and peak power. Incorporate energy storage into the balance according to different guarantee rate ranges, and achieve coordinated planning of energy storage capacity and renewable energy installed capacity based on the renewable energy absorption capacity calculation method in Step 2.

[0131] Step 3 specifically involves proposing the "equal area rule" based on the two sets of new energy power generation sequences to determine the energy storage capacity and peak power, such as... Figure 5 As shown, a scheme for incorporating energy storage into the balance is presented.

[0132] Step 3.1: Calculate two sets of new energy power generation sequences.

[0133] Following the method in step 2.3, the absorption capacity is obtained as x. i The sequence of daily new energy supply disruption hours throughout the year in n is the number of days in the calendar year. Simultaneously, following the method in step 2.4, the daily new energy interval hourly rate sequence ΔT is obtained. i =[ΔT i,1 ,ΔT i,2 ,...,ΔT i,n ], where ΔT i,1 ≤ΔT i,2 ,...,≤T i,n .

[0134] Step 3.2: Calculate the energy storage configuration parameters according to the "equal area rule".

[0135] Step 3.2.1, Determine the energy storage capacity:

[0136] To meet the new energy utilization rate η * According to the requirements, energy storage should absorb the maximum daily electricity consumption of new energy sources. This is equivalent to increasing the renewable energy absorption capacity from x i Raise to x * x i This is called the energy storage operating position, where the energy storage only operates at full capacity on one day of the year, and there is a large amount of idle capacity on the other days. We should look for better energy storage configuration methods.

[0137] Assume the number of hours for converting energy storage capacity to the installed capacity C of new energy sources is T. b , n identical T b Composition sequence T b =[T b,1 ,T b,2 ,...,T b,n ], where T b,1 =T b,2 ,...,=T b,n Let n = [1, 2, ..., n] be the ordered set of days. Let sequence n be the independent variable and sequence T be the independent variable. b , ΔT i The three sets of curves F1, F2, and F3 obtained by fitting the dependent variable are shown in the following equations:

[0138]

[0139] Where τ is a continuous number in the range [0, n]. Let the intersection points of F1 with F2 and F3 be O, O, and O, respectively. + (τ A ,F2(τ A )) and O - (τ B ,F3(τ B If ), then there exist two areas S1 and S2:

[0140]

[0141] The goal of energy storage is to utilize the annual renewable energy hours. Absorb all. In O - Before the point, the energy storage hours converted to [amount]. Greater than or equal to Its surplus capacity allows it to absorb an additional S1 hours of renewable energy generation. In O - After clicking, Less than Therefore, the number of fewer renewable energy generation hours absorbed is S2. Finding a suitable T... b , making O - If the amount of electricity absorbed by the energy storage before and after the point is equal, i.e., S1 = S2, then T is at this point. b Significantly smaller than This means that while achieving the target for new energy utilization, energy storage capacity is saved, a principle known as the "equal area rule".

[0142] The optimal T can be found using the following method. b Let ΔS = |S1 - S2| represent the area difference, and set the target for the area difference as a minimum value Erro. ​​Let T b from The increments are made in small steps μ until ΔS is less than the target deviation Erro, at which point T is reached. b Optimal conversion hours for energy storage Energy storage capacity for:

[0143]

[0144] Step 3.2.2: Determine the peak energy storage power and energy storage duration.

[0145] Once confirmed, O + O - Two points are sufficient to determine this. Let τ P =ceil(τ B ), where ceil represents rounding up, for example ceil(0.35) = 1, ceil(1.95) = 2, thus obtaining the day index in n = [1, 2, ..., n] corresponding to the minimum ΔS. Let P o =[P o,1 ,P o,2 ,...,P o,N ] is the τth P The per-unit value of the theoretical power of Tianxin Energy means that energy storage needs to be generated from the working position x. i Start x i ~max(P o The theoretical power of new energy sources between ) is fully absorbed.

[0146] The minimum peak power requirement for energy storage and energy storage duration As shown in the following formula:

[0147]

[0148] Step 3.2.3, determine the annual utilization hours of energy storage:

[0149] The energy storage utilization mode is set to a daily cycle. The lower limit of the absorption capacity range is x. i The corresponding new energy utilization rate is η i upper limit of interval x * The corresponding new energy utilization rate is η * The annual electricity consumption of new energy sources is E. G The annual throughput of energy storage, calculated based on the installed capacity of new energy sources, is in hours. Annual utilization hours of energy storage Calculate according to the following formula:

[0150]

[0151] The method for determining energy storage configuration parameters through the above process is called the "equal area rule" method. From this, the guaranteed hours for the new energy range can be obtained. Energy storage capacity Peak power of energy storage Energy storage duration and annual utilization hours

[0152] Step 3.3: Incorporate energy storage into the balance and corresponding new energy installed capacity planning within regions with different guarantee rates.

[0153] Step 3.3.1, within the guaranteed area.

[0154] According to step 2.5, when the lower limit of the absorption capacity range x i ∈x in At that time, the number of hours in the new energy range with probability r%. If the value is greater than 0, then the new energy source can provide electricity that can be stored. It can be shifted to the evening peak load period with an r% confidence rate, thereby replacing the start-up of thermal power plants in the balance.

[0155] γ represents the overall energy storage charging and discharging efficiency, and T represents the total energy storage efficiency. P x represents the maximum duration of the peak load. o For the initial absorption capacity of new energy, where 0≤o≤m, x i As the energy storage operating location, the capacity of energy storage replacing thermal power is standardized by the new energy installed capacity. The resulting increase in new energy absorption capacity is Δx, as shown in the following formula:

[0156]

[0157] Based on the above formula, the installed capacity C of new energy can be obtained:

[0158]

[0159] Meanwhile, there is a 1-r% probability throughout the year that the number of hours of disruption to new energy sources will be insufficient. At this point, the energy storage system absorbs electricity from thermal power plants to supplement the power supply, allowing it to replace thermal power plants with a predetermined daily output. Since the set percentage (r%) is generally higher than 90%, the energy storage system can absorb electricity from lower-priced renewable energy sources for extended periods and purchase relatively higher-priced thermal power for shorter periods, thus achieving good economic benefits throughout the year.

[0160] Step 3.3.2, within the guaranteed destruction area.

[0161] According to step 2.5, when the lower limit of the absorption capacity range x i ∈x out At that time, the number of hours in the new energy range with probability r%. If the value equals 0, then new energy sources cannot provide enough electricity for energy storage and cannot be used to stably and reliably replace thermal power. At this point, the energy storage operating position is x. i This refers to the initial absorption capacity of new energy (x0). The installed capacity of new energy (C) is calculated using the following formula:

[0162]

[0163] Once the installed capacity of new energy sources is obtained, the proportion of new energy power generation can be calculated according to step 1, as shown in the following formula:

[0164]

[0165] Step 4: Based on the target utilization rate of new energy and the absorption curve from Step 2, determine the upper limit of new energy absorption capacity. Iterate through the lower limit of new energy absorption capacity. For each absorption interval determined by the upper and lower limits, use the "equal area rule" from Step 3 to calculate the corresponding energy storage capacity, peak power, energy storage duration, and new energy installed capacity, forming a calculation result set. Step 4 specifically involves:

[0166] Let i increase by 1 each time from 1 to m, corresponding to the lower limit x of the interval. i From 0 to x * The variation between them. For each group, x i and x * The interval is formed, and the guaranteed number of hours for the interval is calculated. Energy storage to replace thermal power generation capacity Energy storage capacity Peak power of energy storage Energy storage duration and annual utilization hours of energy storage The result set is shown in the following formula:

[0167]

[0168] Step 5: Based on the boundary conditions of grid balance in the planning year, classify and discuss the known and unknown situations of new energy installed capacity, and determine the energy storage configuration parameters for the planning year from the result set of Step 4 based on the scenario extraction method.

[0169] Depending on whether the installed capacity of new energy sources is known, scenarios are extracted from the results set of step 4 to determine the energy storage capacity and peak power for the year to be planned.

[0170] Step 5.1 specifically involves: when the installed capacity of new energy sources is known, according to... Figure 6 The process shown determines the energy storage parameters.

[0171] Based on the system's maximum load in the planned year Load factor Reserve rate Conventional power supply peak shaving rate New energy installed capacity Once the boundaries are known, determine the initial renewable energy absorption capacity according to step 1. Reuse the results set from step 4 Calculate all possible lower limits of absorption capacity As shown in the following formula:

[0172]

[0173] by As the independent variable, As the dependent variable, the fitted curve G1 is obtained, as shown in the following equation:

[0174]

[0175] Based on the result set from step 4, with x i As the independent variable, As the dependent variable, the fitted curve G2 is obtained, as shown in the following equation:

[0176]

[0177] Let the x-coordinate of the intersection point of curves G1 and G2 be x. G Using x G By interpolating the result set obtained in step 4, the planned energy storage capacity can be obtained. Peak power Energy storage duration and energy storage utilization hours

[0178] Step 5.2 specifically involves: when the installed capacity of new energy sources is unknown, following the... Figure 7The process shown calculates and collaboratively determines the energy storage capacity and the installed capacity of new energy sources.

[0179] Based on the conventional power peak shaving rate of the planned year and x in the result set of step 4 i and The initial absorption capacity set of new energy sources can be obtained.

[0180]

[0181] Based on the calculation method for renewable energy absorption capacity in step 1, and the maximum power generation load of the system in the planned year... Load factor Reserve rate Given the given conditions, the set of new energy installed capacity can be obtained. That is, in x i The installed capacity of new energy sources is obtained when the value varies between 0 and x0.

[0182]

[0183] Energy storage configuration parameters can be accessed via x i Determine by corresponding to the result set in step 4:

[0184]

[0185] At this point, the obtained energy storage and new energy installed capacity is a multiple solution consisting of m sets of values. The new energy installed capacity and the corresponding energy storage parameters can be selected according to the desired combination.

[0186] Example

[0187] The theoretical power dataset of new energy sources used in this invention comes from the power grid dispatch EMS system. Taking a real power grid as an example, a power system balance model containing new energy sources is established, and statistical characteristics such as the new energy absorption characteristic curve, interval hours, and guaranteed hours are extracted. This is conducive to the "two coordinations" between power grid balance and the characteristics of new energy sources themselves, and between the new energy absorption capacity and the working position of energy storage.

[0188] Based on the characteristics of new energy consumption, an "equal area rule" model is established to carry out energy storage configuration, accurately matching energy storage capacity with new energy consumption capacity, achieving optimal energy storage configuration under the given new energy consumption target, and incorporating energy storage into grid reserve and balance by guaranteeing the number of hours, obtaining a complete set of parameters such as peak power of energy storage, energy storage duration and annual utilization hours under different new energy consumption capacity scenarios.

[0189] Based on the two scenarios of known and unknown installed capacity of new energy in the planned year, and using methods such as fitting and interpolation, scenarios are extracted from the set of energy storage configuration results for multiple consumption scenarios to obtain the energy storage and new energy configuration schemes for the planned year. This is conducive to conducting grid balance capacity analysis and collaborative planning of multiple power sources such as energy storage for new energy consumption.

[0190] Simulation calculations verified that the power grid balance model can quickly solve the problem of renewable energy consumption. The statistical characteristics of renewable energy show strong inertia to changes in installed capacity and resources. The energy storage capacity obtained by the "equal area rule" configuration is significantly better than that of traditional methods. The energy storage and renewable energy collaborative planning method based on scenario extraction can be effectively used for power grid planning.

Claims

1. The "equal area rule" method for coordinated planning of energy storage and new energy sources, characterized in that... The specific steps are as follows: Step 1: Analyze the grid balance including new energy sources to obtain the per-unit value of new energy absorption capacity x and the proportion of new energy power generation R; Step 2: Analyze the theoretical power sequence of new energy sources, and calculate the characteristic curve of new energy absorption capacity and the characteristic index of guaranteed hours of new energy range according to the per-unit value x of new energy absorption capacity obtained in Step 1. Step 3: Based on the new energy consumption curve obtained in Step 2, the "equal area rule" is proposed according to the two sets of power increase sequences to determine the energy storage capacity and peak power, and the energy storage is incorporated into the balance according to different guarantee rate ranges; Step 3 specifically includes: Step 3.1: Establish the "equal area rule" model to determine the energy storage capacity, specifically as follows: Step 3.1.1 yields two hourly ascending sequences: （1）； in, For the capacity to absorb new energy The corresponding number of hours of disruption to new energy sources per day. For new energy vehicle range hours; Step 3.1.2, let the number of hours on the new energy installed capacity be the converted value of energy storage capacity. ,make Then we get the following two sets of areas: （2）； In the formula, " "" indicates the curve fitted to the corresponding sequence with the set of calendar days n as the independent variable. and They are respectively The intersection point with the other two fitted curves; make To represent the area difference, we set the area difference objective as a minimum value Erro, and let... From 0 to According to step size Increment, until Stop when the deviation is less than the target Erro. Optimal conversion hours for energy storage Energy storage capacity for: （3）； Where C represents the installed capacity of new energy sources; Peak energy storage power, optimal energy storage hours, and annual energy storage utilization hours are as follows: （4）； In the formula, for The time series of theoretical new energy power corresponding to the minimum day. The annual throughput of energy storage is converted into hours. For theoretical hours of new energy sources; To achieve the target of new energy utilization rate, New energy utilization rate; Step 3.2, based on the guaranteed area, when the new energy absorption capacity... At that time, the guaranteed hours of new energy are replaced by the operation of conventional power sources through energy storage relocation. According to the calculation method of new energy absorption capacity in step 1, the installed capacity of new energy is obtained as follows: （5）； In the formula, For the overall charging and discharging efficiency of energy storage, The maximum duration of the load peak; sequence To meet the guarantee rate The set of lower limits of absorption capacity under the required conditions is called the guaranteed region; Indicates the maximum power generation load. Indicates the guaranteed number of hours for the interval; When the new energy absorption capacity hour, The value is 0, so the installed capacity of new energy is: （6） Among them, sequence Unable to meet the guarantee rate The set of lower limits of absorption capacity at any given time is called the guarantee rate violation zone; Step 4: Determine the upper limit of new energy absorption capacity based on the new energy target utilization rate and the absorption curve in Step 2. Iterate through the lower limit of new energy absorption capacity. For each absorption interval determined by the upper and lower limits of absorption capacity, use the "equal area rule" in Step 3 to calculate the energy storage capacity, peak power, energy storage duration and new energy installed capacity corresponding to each absorption capacity interval, and form a set of calculation results. Step 5: Based on the boundary conditions of grid balance in the planning year, classify and discuss the known and unknown situations of new energy installed capacity, and determine the energy storage configuration parameters for the planning year from the result set of Step 4 based on the scenario extraction method.

2. The "equal area rule" method for coordinated planning of energy storage and new energy sources according to claim 1, characterized in that, Step 1 specifically involves: Step 1.1, New Energy Absorption Capacity For system power generation load Subtract the minimum output of conventional units As shown in the following formula: （7）； Conventional unit operating capacity From the system's maximum power generation load and reserve rate Calculations show that the maximum generating load is equal to the average load. Divide by load factor It is found that the minimum output of a conventional unit is determined by its operating capacity and peak shaving rate. To determine this, as shown in the following formula: （8）； New energy absorption capacity The energy in the storage space is obtained by accumulating points. This also equals the average absorption capacity of new energy sources. The product of the statistical period T and the system power generation load The total power generation is obtained by integration. It is also equal to the average load. The product of the product with the statistical period T is shown in the following formula: （9）； Further improve the average absorption capacity of new energy sources As shown in the following formula: （10）； Step 1.2, the per-unit value x of the renewable energy absorption capacity is the average renewable energy absorption capacity. Divide by the installed capacity of new energy sources C, and define the installed capacity of new energy sources C and the maximum power generation load. The ratio is the penetration rate of new energy. The per-unit value x of the new energy absorption capacity is then obtained as shown in the following formula: （11）； in, Define the theoretical hours of new energy sources as the theoretical electricity output. The proportion of new energy resources in the statistical period T is represented by the new energy resource coefficient s, and the proportion of new energy power generation R is obtained as shown in the following formula: （12）。 3. The "equal area rule" method for coordinated planning of energy storage and new energy sources according to claim 2, characterized in that, Step 2 specifically involves: Step 2.1, standardize the theoretical power of new energy sources, specifically as follows: The theoretical power of renewable energy sources in the power grid is collected over the entire year and normalized using renewable energy installed capacity. The theoretical power at time j is then calculated within a time series of length M. Dividing by the installed capacity of new energy sources, C, yields the theoretical per-unit power value. As shown in the following formula: （13）； Step 2.2: Calculate the actual power and utilization rate of new energy sources; Divide the installed capacity of new energy into m small intervals, and let i from The increments by 1 each time. The size of the i-th interval is the per-unit value of the new energy absorption capacity obtained in step 1, compared with... and The theoretical power that does not exceed the absorption capacity is the actual power of new energy. As shown in the following formula: （14）； For the i-th installed capacity range, the ratio of actual power integral energy to theoretical power per-unit integral energy is the renewable energy utilization rate. As shown in the following formula: （15）； Let i vary continuously between 1 and 100 to obtain the renewable energy absorption capacity for each group. and the corresponding new energy utilization rate ,by As the independent variable, The relationship curve between the two variables is called the new energy consumption curve; Step 2.3, calculate the number of hours for the new energy vehicle segment, specifically as follows: Set new energy utilization rate targets Using the absorption curve obtained in step 2, find the per-unit value of the new energy absorption capacity corresponding to the target utilization rate. , order 0~ Given any one of the two sets of new energy absorption capacities, under the above two sets of new energy absorption capacities... , They are time j respectively , The power of renewable energy is hindered, where C is the installed capacity of renewable energy and N is the length of the daily theoretical power sequence of renewable energy. , They are respectively , The corresponding number of daily obstruction hours for new energy sources is shown in the following formula: （16）； by For the lower limit, The upper limit is defined as a range of renewable energy absorption capacity, within which the theoretical power hours of renewable energy are: This is called the new energy range hours, as shown in the following formula: （17）； Step 2.4, calculate the guaranteed hours for the new energy range, specifically: The daily hourly intervals throughout the year were statistically analyzed and then arranged in ascending order to obtain the sequence. ,in Let n be the number of days in a calendar year, and a given probability be... Then the corresponding hour quantile is: （18）； in, It is an integer, where floor represents rounding down according to the quantile. The index, from the interval hour number to the sequence Find the corresponding value in the middle, that is... The number of guaranteed hours for the corresponding probability interval ,express China Super League The proportion of the number of elements in the total number of elements is , Also known as the guarantee rate: （19）； Step 2.5, divide the protected area, specifically as follows: m represents the number of new energy installed capacity ranges in step 2.

2. Let i increase by 1 from 1 to m each time. For each group... and The formed interval will As the lower limit of the interval As the upper limit of the interval, the guaranteed hours for each interval are counted and sorted in ascending order to obtain an ascending sequence. ,in If there exists an integer k less than m that satisfies: （20）； Then it is called For probability The corresponding critical guarantee hours for the interval. This represents the lower limit critical value of the corresponding new energy absorption capacity range.

4. The "equal area rule" method for coordinated planning of energy storage and new energy sources according to claim 3, characterized in that, Step 4 specifically involves: determining the upper limit of new energy absorption capacity based on the new energy target utilization rate and the absorption curve from Step 2, and iterating through the lower limit of new energy absorption capacity; using the "equal area rule" from Step 3, calculating the energy storage capacity, peak power, energy storage duration, and new energy installed capacity corresponding to each absorption capacity range, forming a set of calculation results. （21）； In the formula, To guarantee the number of hours in the interval, To replace thermal power generation capacity with energy storage For energy storage capacity, For energy storage peak power, For optimal energy storage hours, This refers to the annual utilization hours of energy storage.

5. The "equal area rule" method for coordinated planning of energy storage and new energy sources according to claim 4, characterized in that, Step 5 specifically involves: Step 5.1, when the planned annual installed capacity of new energy is known, is as follows: （22）； In the formula, For the maximum load of the system in the planned year, For load factor, For reserve rate, For conventional power supply peak regulation rate, Given the known boundary of new energy installed capacity, This refers to the initial renewable energy absorption capacity determined in step 1; Step 5.2, when the planned annual installed capacity of new energy is unknown, the obtained installed capacity of new energy is: （23）； In the formula, For the planned new energy installed capacity, determine the energy storage configuration parameters according to the result set in step 4.

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