New energy power generation curve differentiation assessment method considering line transmission congestion

Abstract

The invention discloses a new energy power generation curve differentiation assessment method considering line transmission congestion, and belongs to the technical field of novel power system scheduling and operation, and the method comprises the steps: building an RES daily time scale power curve differentiation deviation assessment mechanism considering power transmission line congestion and regional power grid comprehensive regulation and control demands; setting an assessment mechanism correction method considering the BESS use efficiency and the assessment fairness, wherein the assessment mechanism correction method is used for adjusting the weights of the BESS use efficiency and the assessment fairness in the optimization target; and establishing a comprehensive evaluation index for the operation effect of the assessment mechanism, assisting in quantifying the implementation effect of the assessment mechanism, and guiding the weight setting of the BESS use efficiency and assessment fairness. According to the method, a differentiation assessment mechanism is provided, the fairness and the BESS comprehensive regulation and control efficiency can be effectively considered, and the fairness of the mechanism can be enhanced by improving the weight coefficient alpha fair in an area where the flexibility regulation and control capacity of a superior power grid is sufficient.

Description

Technical Field

[0001] The present invention belongs to the technical field of new power system dispatching and operation, and specifically relates to a differentiated assessment method for new energy power generation curves taking into account line transmission congestion. Background Art

[0002] In the new power system, the proportion of new energy stations (RES) will exceed that of conventional thermal power units and become the main power source of the power grid. At this time, if RES still cannot provide a reliable daily time scale power generation plan curve, the power grid will be unable to use a small number of conventional thermal power units to raise sufficient short-term peak-shaving resources and backup resources, which will seriously threaten the safe operation of the power grid. To solve this problem, local governments have widely required RES to independently build a battery energy storage system (BESS) with an installed capacity of 10% to 20% to solve some power deviations and fluctuations locally. However, the utilization efficiency of RES self-built BESS is very low at present. In 2022, the daily equivalent utilization of RES equipped with BESS is only 0.22 times, which is much lower than that of independent BESS and user-side BESS. This results in RES having a certain degree of autonomous regulation capability but being idle, while the poor power generation plan execution capability of the station consumes a large amount of grid-side regulation resources. The main reason for this contradiction is that the assessment mechanism is unclear. RES is not subject to real-time and accurate assessment requirements, so there is no motivation to call BESS, and it can only do simple peak shaving and valley filling, resulting in extremely low BESS utilization efficiency.

[0003] The assessment of the power curve of RES does not mean that the BESS equipped with RES must bear the task of correcting the power deviation 100%, which is neither economical nor necessary. There is a certain complementary effect between the power deviation of RES in the regional power grid. The energy gap and surplus can be offset by each other through the line. The power grid only needs to track the total power plan of the external interconnection line. However, this complementarity is also limited. If the transmission line is blocked, the RES can only call the BESS locally to correct the power deviation. At present, distributed photovoltaics are often configured in rural distribution networks with weak grid structures. During the period of large-scale new energy generation, line blockage often occurs, so its impact on the complementary effect of RES power deviation cannot be ignored. In addition, each RES is an independent market entity, and its individual interests and overall interests are sometimes not completely consistent. If the above method is used to analyze the comprehensive regulation needs of the power grid and consider the complementary effect between RES in order to maximize the use efficiency of BESS, there is the following situation: in the same period, different RES only need to call BESS due to different grid positions and power deviation directions, resulting in the "unfair" phenomenon that some RES need to call BESS while others do not need to call. In order to improve the utilization efficiency of BESS, the temporary "unfairness" caused by this differentiated deviation assessment is difficult to avoid, but by adjusting the optimization target and other methods, the deviation assessment pressure received by each RES during the long-term operation can be proportional to its total deviation, that is, fairness in a statistical sense can be achieved. Therefore, a differentiated assessment method for renewable energy power generation curves that takes into account line transmission congestion is needed. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide a method for differentiating the assessment of new energy power generation curves taking into account line transmission congestion, thereby solving the problems in the above-mentioned background technology.

[0005] The object of the present invention is achieved as follows: a method for differentiated assessment of new energy power generation curves considering line transmission congestion, which comprises the following steps: S1, establishing a differentiated deviation assessment mechanism for RES power curves on a daily time scale considering transmission line congestion and comprehensive regulation and control requirements of regional power grids; S2, setting an assessment mechanism correction method that takes into account BESS utilization efficiency and assessment fairness, which is used to adjust the weights of BESS utilization efficiency and assessment fairness in the optimization target; S3, establishing a comprehensive evaluation index for the operation effect of the assessment mechanism, assisting in quantifying the implementation effect of the assessment mechanism, and guiding the weight setting of BESS utilization efficiency and assessment fairness.

[0006] Furthermore, the establishment of a differentiated deviation assessment mechanism for RES power curves on a daily time scale that takes into account transmission line congestion and the needs of comprehensive regulation of regional power grids includes establishing an optimization target for RES assessment requirements in each period, namely, minimizing the deviation of the external interconnection line plan. The specific expression is:

[0007]

[0008]

[0009] Where: i is the serial number of the regional power grid external connection line; is the actual and planned transmission power of external tie line i during period t, MW; is the power deviation of external interconnection line i in period t, MW; N ex-line is the total number of external connection lines of the regional power grid;

[0010] The external interconnection line deviation is the original power deviation of RES minus the control part of the BESS and then minus the complementary balance part. The calculation method is:

[0011]

[0012] Where: is the RES corresponding to the external tie line i, hereinafter referred to as RES-i, actual and planned power in period t, MW; is the charging and discharging power of the BESS equipped with RES-i during period t, MW, hereinafter referred to as BESS-i; is the actual and planned transmission power of the distribution network transmission line connected to RES-i with sequence number j in time period t, MW; is the total number of distribution network transmission lines connected to RES-i;

[0013] The calculation method for the assessment requirements of RES-i in period t is:

[0014]

[0015] Where: is the assessment requirement of the power grid for RES-i in period t. When it is a positive value, BESS-i takes charging action, and when it is a negative value, BESS-i takes discharging action, MW.

[0016] Furthermore, the upper limit constraint of the assessment intensity is set according to the average BESS supporting construction of regional power grid RES. The formula is:

[0017]

[0018] Where: is the maximum assessment range that the power grid can issue, MW; The rated capacity of the BESS equipped with the kth RES in the regional power grid, MWh; N BESS is the total number of BESSs equipped with RES in the regional power grid; Δt is the length of the dispatch period, h, and Δt = 0.25h;

[0019] Is the impact and Assessment requirements The variable whose value range satisfies the line blocking constraint is expressed as follows:

[0020]

[0021] Where: is the maximum transmission power of the distribution network transmission line with RES-i number j, MW.

[0022] Furthermore, the assessment mechanism correction method that takes into account both BESS utilization efficiency and assessment fairness includes an assessment fairness index, and the technical method of the assessment fairness index is specifically:

[0023]

[0024] Where: R fair is the fairness assessment index; t,i is the ratio of the power deviation correction task of RES-i in period t to the original power deviation; is the δ of all RES-i in period t t,i Mean; N T It is the total number of scheduling periods within the statistical period.

[0025] Furthermore, the assessment mechanism correction method that takes into account both BESS utilization efficiency and assessment fairness includes a BESS utilization efficiency index, and the technical method of the BESS utilization efficiency index is specifically:

[0026]

[0027] Where: R BESS It is the BESS utilization efficiency index.

[0028] Furthermore, the establishment of the comprehensive evaluation index of the operation effect of the assessment mechanism includes normalizing the original optimization target, and integrating the normalized optimization target, the assessment fairness index and the BESS utilization efficiency index after re-weighting to form a new optimization target. The original optimization target after normalization is:

[0029]

[0030] Where: R ex-line is the normalized external interconnection line power deviation index, R ex-line The larger the value is, the greater the external connection line power deviation is, that is, the worse the implementation effect of the assessment mechanism is. BESS The larger the value of is, the higher the efficiency of BESS is, that is, the better the implementation effect of the assessment mechanism is. fair The smaller the value of, the more fair the assessment mechanism is;

[0031] Comprehensive evaluation index R effect With R ex-line and R fair Negatively correlated with R BESS There is a positive correlation. The calculation method of the comprehensive evaluation index of the operation effect of the assessment mechanism is:

[0032] R effect =α BESS R BESS -α fair R fair -α ex-line R ex-line (13)

[0033] stα BESS ≥0 (14)

[0034] stα fair ≥0 (15)

[0035] stα ex-line ≥0 (16)

[0036] Where: R effect is a comprehensive evaluation index of the operation effect of the assessment mechanism; ex-line , α BESS and α fair To calculate R effect Time R ex-line , R BESS and R fair The weight coefficient of .

[0037] Furthermore, the optimization target after correction is:

[0038] max R effect (17)

[0039] If the external connection line power deviation in the optimization result is too large, increase α ex-line If the BESS efficiency is too low, increase α BESS If the assessment is not fair, increase α fair Numeric value;

[0040] Establish BESS operation constraints, including the state of charge range constraints and the maximum charge and discharge power constraints. The constraints are:

[0041]

[0042] SOC min SOC t SOC max (19)

[0043]

[0044]

[0045] Where: SOC t is the SOC of BESS during period t; SOC min , SOC max is the highest and lowest SOC of BESS; E G is the rated capacity of BESS, MWh; γ ch , γ dch is the charging and discharging efficiency of BESS; Δt is the length of the scheduling period, h, and Δt = 0.25h; is the maximum charging and discharging power of BESS, MW.

[0046] Beneficial effects of the present invention: Compared with the prior art, the proposed differentiated assessment mechanism can effectively balance fairness and the comprehensive control efficiency of BESS. In areas where the flexibility control capacity of the upper power grid is relatively sufficient, the weight coefficient α can be increased. fair To enhance the fairness of the mechanism, the weight coefficient α can be increased when the regulatory capacity is scarce. ex-line and α BESS Improve the use efficiency of BESS and reduce the external transmission power deviation as much as possible. In summary, this method is highly flexible. Compared with the traditional one-size-fits-all homogeneous assessment, it can adapt to a richer range of usage scenarios, achieve statistical fairness, and has a higher promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 Schematic diagram of the complementary effect of power deviation between RESs and the influence of transmission line congestion on the complementary effect of the present invention;

[0048] Figure 2 It is a schematic diagram of fair assessment in the statistical sense of the present invention;

[0049] Figure 3 It is a schematic diagram of the original power curve of four RES in the power grid of the present invention within 30 days;

[0050] Figure 4 It is a schematic diagram of the change curve of the total deviation electric energy of the external connection line within 30 days under the two weight settings of the present invention;

[0051] Figure 5 It is a schematic diagram of the change curve of the total deviation electric energy of the external connection line within 30 days under the two weight settings of the present invention;

[0052] Figure 6 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below in conjunction with the accompanying drawings, just to more clearly illustrate and explain the present invention.

[0054] like Figure 1-6 As shown, this embodiment discloses a method for differentiated assessment of new energy power generation curves considering line transmission congestion, including the following steps:

[0055] Step 1: Establish a differentiated deviation assessment mechanism for RES power curves on a daily time scale that takes into account transmission line congestion and the needs of comprehensive regulation of regional power grids.

[0056] For regional power grids, ensuring the execution of external interconnection line plans and reducing the purchase of short-term peak load regulation and backup resources are the main optimization goals. The power deviation of each RES is the main reason for the deviation of the interconnection line plan. Therefore, implementing power deviation assessment on each RES and encouraging it to call the equipped BESS to autonomously correct part of the power deviation is the main means to solve the deviation of the interconnection line plan.

[0057] like Figure 1 As shown in the figure, each RES is not only connected to the upper power grid, but also connected to each other through the distribution network. Some power deviations can be balanced through these distribution transmission lines. Therefore, the planned deviation of the regional power grid's external interconnection line is not a simple sum of the power deviations of each RES. However, the capacity of the distribution transmission line is usually low and may be blocked, which may weaken the complementary effect between RES. This should also be taken into account when issuing assessment requirements.

[0058] First, the optimization goal of RES assessment requirements for each period is established, that is, minimizing the deviation of the external contact line plan. The specific expression is as follows:

[0059]

[0060] Where: i is the serial number of the regional power grid external connection line; is the actual and planned transmission power of external tie line i during period t, MW; is the power deviation of external interconnection line i in period t, MW; N ex-line It is the total number of external interconnection lines of the regional power grid.

[0061] like Figure 1 As shown in the figure, the external interconnection line deviation is the original power deviation of RES minus the control part of the built BESS minus the complementary balance part. The calculation method is as follows:

[0062]

[0063] Where: is the actual and planned power of the RES corresponding to the external tie line i (hereinafter referred to as RES-i) in period t, MW; is the charging and discharging power of the BESS equipped with RES-i (hereinafter referred to as BESS-i) in period t, MW; is the actual and planned transmission power of the distribution network transmission line connected to RES-i with sequence number j in time period t, MW; is the total number of distribution network transmission lines connected to RES-i.

[0064] and All are known during optimization, so the optimal charging and discharging power of BESS can be optimized Regardless of whether BESS-i is really capable of performing such charging and discharging actions during period t, the power grid can make such assessment requirements for it. As for the part that cannot be completed, RES can choose to pay a certain assessment fee.

[0065] The calculation method for the assessment requirements of RES-i in period t is as follows:

[0066]

[0067] Where: is the assessment requirement of the power grid for RES-i in period t. When it is a positive value, BESS-i is required to take charging action. When it is a negative value, BESS-i is required to take discharging action, MW.

[0068] Of course, given that RES is usually only equipped with small and medium-sized BESS, it is not possible to impose unlimited assessment requirements on RES. If the assessment requirements greatly exceed the bearing capacity of RES, the economic interests of the station will be seriously damaged, which will make the assessment mechanism unable to be promoted. Therefore, it is necessary to set an upper limit constraint on the assessment intensity based on the average BESS supporting construction of RES in the regional power grid. The formula is as follows:

[0069]

[0070] Where: is the maximum assessment range that the power grid can issue, MW; The rated capacity of the BESS equipped with the kth RES in the regional power grid, MWh; N BESS is the total number of BESSs equipped with RES in the regional power grid; Δt is the length of the dispatch period, h, and this paper takes Δt = 0.25h.

[0071] Is the impact and Assessment requirements The important variable of is, and its value range must also satisfy the line blocking constraint. The expression is as follows:

[0072]

[0073] Where: is the maximum transmission power of the distribution network transmission line with RES-i number j, MW. So far, the assessment requirements of the power grid for each RES can be preliminarily determined.

[0074] Step 2: Design an assessment mechanism correction method that takes into account both BESS efficiency and assessment fairness, which is used to adjust the weights of BESS efficiency and assessment fairness in the optimization objectives.

[0075] If we directly solve the optimization model in step 1 The efficiency of BESS built with each RES can be maximized, but some RES may be subject to stricter assessment than other RES due to the influence of the grid structure. At this time, the assessment mechanism is unfair to these sites. Therefore, the optimization model in step 1 should be corrected and improved to take into account the efficiency of BESS and the fairness of assessment.

[0076] Before proposing the correction method, we first introduce what is fair assessment in a statistical sense. Since the charging and discharging actions of the BESS will reduce the service life of the BESS, the autonomous correction of the power deviation by the RES is inevitably accompanied by a certain adjustment cost. If the deviation power between different RES can be balanced with each other through the distribution network transmission line, but the grid dispatching department deliberately pursues absolute fairness and requires RES to adjust according to the same standard, it may reduce the life of the BESS in vain, greatly reducing the actual use efficiency of the BESS. Therefore, we cannot deliberately pursue absolute fairness in each time period, and we must implement differentiated assessments for different RES.

[0077] However, this differentiated assessment does not mean that the assessment mechanism is unfair. Figure 2 As shown in the figure, RES-1 was not assessed during period t, but RES-2 was. If the power deviations of the two are the same at this time, the assessment is unfair for this period. However, this unfairness is random and not intentionally created by RES. If the running time is extended and it is found that the probability and strictness of each RES being assessed are similar in a statistical sense, then the assessment mechanism can be considered to be fair in a statistical sense.

[0078] The calculation method of the assessment fairness index is as follows:

[0079]

[0080] Where: R fair is the fairness assessment index; t,i is the ratio of the power deviation correction task of RES-i in period t to the original power deviation; is the δ of all RES-i in period t t,i Mean; NT It is the total number of scheduling periods within the statistical period.

[0081] When correcting the optimization target established in step 1, the efficiency of the BESS built with RES must also be considered. The so-called efficient use of BESS means that the unit charge and discharge capacity of BESS can correct more external interconnection line plan deviations.

[0082] The calculation method of BESS utilization efficiency is as follows:

[0083]

[0084] Where: R BESS It is the BESS utilization efficiency index.

[0085] Determine the power deviation to be assessed for each RES. If only the minimization of the external interconnection line power deviation shown in formula (1) is used as the optimization goal, it may lead to large differences in the assessment pressure on each RES. If the same deviation assessment requirements are implemented on all RES in a one-size-fits-all manner, it may mislead the RES to make invalid or inefficient adjustment actions. In summary, when minimizing the external interconnection line power deviation, the fairness of the assessment and the efficiency of BESS use must also be considered comprehensively.

[0086] Step 3: Establish comprehensive evaluation indicators for the effectiveness of the assessment mechanism to assist in quantifying the effectiveness of the implementation of the assessment mechanism and guide the weight setting of BESS usage efficiency and assessment fairness.

[0087] When optimizing the power deviation assessment requirements for each RES, a comprehensive evaluation index for the operating effect of the assessment mechanism can be established, and the original optimization target can be normalized. Finally, the normalized optimization target, assessment fairness index and BESS utilization efficiency index can be integrated after re-weighting to form a new optimization target.

[0088] The original optimization objective shown in formula (1) is normalized as follows:

[0089]

[0090] Where: R ex-line It is the power deviation index of the external connection line after normalization.

[0091] R ex-line The larger the value is, the greater the power deviation of the external contact line is, that is, the worse the implementation effect of the assessment mechanism is. BESS The larger the value of is, the higher the efficiency of BESS is, that is, the better the implementation effect of the assessment mechanism is. fair The smaller the value, the more fair the assessment mechanism is.

[0092] Therefore, the comprehensive evaluation index R effectWith R ex-line and R fair Negatively correlated with R BESS The calculation method of comprehensive evaluation index of the operation effect of the assessment mechanism is as follows:

[0093] R effect =α BESS R BESS -α fair R fair -α ex-line R ex-line (13)

[0094] stα BESS ≥0 (14)

[0095] stα fair ≥0 (15)

[0096] stα ex-line ≥0 (16)

[0097] Where: R effect is a comprehensive evaluation index of the operation effect of the assessment mechanism; ex-line , α BESS and α fair To calculate R effect Time R ex-line , R BESS and R fair The weight coefficient of .

[0098] In summary, the optimization objective after correction is changed from formula (1) to the following:

[0099] max R effect (17)

[0100] If the external connection line power deviation in the optimization result is too large, increase α ex-line If the BESS efficiency is too low, increase α BESS If the assessment is not fair, increase α fair Numeric value.

[0101] The present invention will verify the implementation effect of the proposed assessment mechanism through a group of embodiments. Therefore, the operation process of RES in the assessment mechanism should be simulated. During the process, BESS should be called to implement charging and discharging actions. Therefore, BESS operation constraints should be established, including state of charge (SOC) value range constraints and maximum charging and discharging power constraints.

[0102]

[0103] SOC min SOC tSOC max (19)

[0104]

[0105] Where: SOC t is the SOC of BESS during period t; SOC min , SOC max is the highest and lowest SOC of BESS; E G is the rated capacity of BESS, MWh; γ ch , γ dch is the charging and discharging efficiency of BESS; Δt is the length of the scheduling period, h, and this paper takes Δt = 0.25h; is the maximum charging and discharging power of BESS, MW.

[0106] A set of examples are used to verify the effectiveness of the operating method proposed in the present invention.

[0107] Scenario setting: A regional power grid includes 4 RESs. Their original power curve measured data within 30 days are as follows: Figure 3 shown.

[0108] The technical parameters of BESS equipped with each RES are shown in Table 1.

[0109] Table 1 Technical parameters of BESS

[0110]

[0111] If there is a line L between RES-n and RES-m n,m , L n,m The maximum transmission power is expressed as It means that there is no line connection between the two stations. Then the transmission line connection between the RES in the entire regional power grid can be expressed as the following matrix:

[0112]

[0113] Where: is the maximum transmission power of the transmission line between RES-n and RES-m, MW; Ω line is the maximum transmission power matrix of regional power grid transmission lines; N R is the total amount of RES in the regional power grid.

[0114] Use Ω line Indicates the technical parameters of the transmission lines between RES in the regional power grid. The scenario settings are as follows:

[0115]

[0116] In addition, assuming that the planned transmission power of each line All are 0. The probability density distribution functions of the power prediction deviation ratios of each RES all satisfy the normal distribution with a mean of 0 and a standard deviation of 0.25.

[0117] Under the above scenario conditions, set the weight coefficient [α ex-line ,α BESS ,α fair ] are two sets of data: [1.00, 1.00, 1.00] and [0.75, 0.75, 1.50]. Comparing the change curves of the total deviation power of the external contact line within 30 days under the two weight settings, as shown in Figure 4 shown.

[0118] Depend on Figure 4 It can be seen that when increasing α fair After lowering the other two weight coefficients, the total deviation power of the regional power grid's external interconnection lines is more balanced than the weight coefficient configuration, which shows that the assessment mechanism at this time pays more attention to the fairness of the assessment. The fairness index R fair The changing trend of Figure 5 shown.

[0119] Depend on Figure 5 It can be seen that although [α ex-line ,α BESS ,α fair ] is [0.75,0.75,1.50], the total deviation power of the external contact line is higher, but the fairness of the assessment mechanism is significantly improved. At this time, RES is more willing to accept the assessment mode, and the promotion resistance of the mechanism is smaller.

[0120] The above example shows that the differentiated assessment mechanism proposed by this method can effectively take into account fairness and the comprehensive control efficiency of BESS. In areas where the upper power grid has sufficient flexibility control capabilities, the weight coefficient α can be increased. fair To enhance the fairness of the mechanism, the weight coefficient α can be increased when the regulatory capacity is scarce. ex-line and α BESS Improve the efficiency of BESS and reduce the external transmission power deviation as much as possible.

[0121] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for evaluating the differentiated curve of renewable energy generation considering line transmission congestion, characterized in that: The following steps are involved: S1. Establish a differentiated deviation assessment mechanism for RES power curves on a daily time scale that takes into account transmission line congestion and the needs of comprehensive regulation of regional power grids; S2. Set up an assessment mechanism correction method that takes into account both BESS efficiency and assessment fairness, which is used to adjust the weights of BESS efficiency and assessment fairness in the optimization objectives; S3. Establish comprehensive evaluation indicators for the effectiveness of the assessment mechanism, assist in quantifying the effectiveness of the implementation of the assessment mechanism, and guide the weight setting of BESS usage efficiency and assessment fairness.

2. The method for evaluating the differentiated new energy generation curve considering line transmission congestion according to claim 1 is characterized in that: The establishment of a differentiated deviation assessment mechanism for RES power curves on a daily time scale that takes into account transmission line congestion and regional power grid comprehensive regulation needs includes establishing an optimization target for RES assessment requirements in each period, that is, minimizing the deviation of the external interconnection line plan. The specific expression is: Where: i is the serial number of the regional power grid external connection line; is the actual and planned transmission power of external tie line i during period t, MW; is the power deviation of external interconnection line i in period t, MW; N ex-line is the total number of external connection lines of the regional power grid; The external interconnection line deviation is the original power deviation of RES minus the control part of the BESS and then minus the complementary balance part. The calculation method is: Where: is the RES corresponding to the external tie line i, hereinafter referred to as RES-i, actual and planned power in period t, MW; is the charging and discharging power of the BESS equipped with RES-i during period t, MW, hereinafter referred to as BESS-i; is the actual and planned transmission power of the distribution network transmission line connected to RES-i with sequence number j in time period t, MW; is the total number of distribution network transmission lines connected to RES-i; The calculation method for the assessment requirements of RES-i in period t is: Where: is the assessment requirement of the power grid for RES-i in period t. When it is a positive value, BESS-i takes charging action, and when it is a negative value, BESS-i takes discharging action, MW.

3. The method for evaluating the differentiated new energy generation curve considering line transmission congestion according to claim 2 is characterized in that: The upper limit constraint of the assessment intensity is set according to the average BESS supporting construction of regional power grid RES. The formula is: Where: is the maximum assessment range that the power grid can issue, MW; The rated capacity of the BESS equipped with the kth RES in the regional power grid, MWh; N BESS is the total number of BESSs equipped with RES in the regional power grid; Δt is the length of the dispatch period, h, and Δt = 0.25h; Is the impact and Assessment requirements The variable whose value range satisfies the line blocking constraint is expressed as follows: Where: is the maximum transmission power of the distribution network transmission line with RES-i number j, MW.

4. The method for evaluating the differentiated renewable energy generation curve considering line transmission congestion according to claim 1 is characterized by: The assessment mechanism correction method that takes into account both BESS use efficiency and assessment fairness includes an assessment fairness index. The technical method of the assessment fairness index is specifically: Where: R fair is the fairness assessment index; t,i is the ratio of the power deviation correction task of RES-i in period t to the original power deviation; is the δ of all RES-i in period t t,i Mean; N T It is the total number of scheduling periods within the statistical period.

5. When correcting the optimization target established in right 1, the efficiency of the BESS built with RES must also be considered. The so-called efficient use of BESS means that the unit charge and discharge capacity of BESS can correct more external interconnection line plan deviations. The specific calculation method of BESS utilization efficiency is as follows: Where: R BESS It is the BESS utilization efficiency index.

6. The method for evaluating the differentiated new energy generation curve considering line transmission congestion according to claim 1 is characterized by: The establishment of the comprehensive evaluation index of the operation effect of the assessment mechanism includes normalizing the original optimization target, restoring the weights of the normalized optimization target, the assessment fairness index and the BESS utilization efficiency index to form a new optimization target. The original optimization target after normalization is: Where: R ex-line is the normalized external interconnection line power deviation index, R ex-line The larger the value is, the greater the external connection line power deviation is, that is, the worse the implementation effect of the assessment mechanism is. BESS The larger the value of is, the higher the efficiency of BESS is, that is, the better the implementation effect of the assessment mechanism is. fair The smaller the value of, the more fair the assessment mechanism is; Comprehensive evaluation index R effect With R ex-line and R fair Negatively correlated with R BESS There is a positive correlation. The calculation method of the comprehensive evaluation index of the operation effect of the assessment mechanism is: R effect =a BESS R BESS -a fair R fair -a ex-line R ex-line (13) stα BESS ≥0 (14) stα fair ≥0 (15) stα ex-line ≥0 (16) Where: R effect is a comprehensive evaluation index of the operation effect of the assessment mechanism; ex-line , α BESS and α fair To calculate R effect Time R ex-line , R BESS and R fair The weight coefficient of .

7. The method for evaluating the differentiated new energy generation curve considering line transmission congestion according to claim 5 is characterized by: The optimization goal after correction is: max R effect (17) If the external connection line power deviation in the optimization result is too large, increase α ex-line If the BESS efficiency is too low, increase α BESS If the assessment is not fair, increase α fair Numeric value; Establish BESS operation constraints, including the state of charge range constraints and the maximum charge and discharge power constraints. The constraints are: SOC min ≤SOC t ≤SOC max (19) Where: SOC t is the SOC of BESS during period t; SOC min , SOC max is the highest and lowest SOC of BESS; E G is the rated capacity of BESS, MWh; γ ch , γ dch is the charging and discharging efficiency of BESS; Δt is the length of the scheduling period, h, and Δt = 0.25h; is the maximum charging and discharging power of BESS, MW.

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