CN111339491A - Evaluation method for urban power distribution network transformation scheme - Google Patents

Evaluation method for urban power distribution network transformation scheme Download PDF

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CN111339491A
CN111339491A CN202010127464.4A CN202010127464A CN111339491A CN 111339491 A CN111339491 A CN 111339491A CN 202010127464 A CN202010127464 A CN 202010127464A CN 111339491 A CN111339491 A CN 111339491A
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罗志刚
韦钢
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Abstract

The invention provides an evaluation method of an urban distribution network transformation scheme, which comprises the steps of establishing a distribution network transformation scheme comprehensive evaluation index system containing indexes such as reliability, power supply capacity, economy, DG (distributed generation) receiving capacity, disaster resistance capacity, adaptability, harmony and the like and a quantitative calculation method of each index, solving the main and objective weights of each index by using an interval intuitive fuzzy analytic hierarchy process and a CRITIC (criterion-likelihood analysis of probability) method, obtaining the comprehensive weight by combining a minimum information identification principle, finally solving the comprehensive evaluation value of each transformation scheme by combining TOPSIS (technique-order analysis of probability) and selecting the optimal transformation scheme according to the maximum comprehensive evaluation value principle of the scheme and delivering the optimal transformation scheme to relevant workers in the technical field for implementation. The index system constructed by the method is simple and easy to calculate, the overall performance of the distribution network transformation scheme can be comprehensively reflected from different angles, and the obtained evaluation result has high identification degree, so that the decision result is more practical, has higher reliability and has higher engineering application value.

Description

Evaluation method for urban power distribution network transformation scheme
Technical Field
The invention belongs to the field of power distribution system transformation, and particularly relates to an evaluation method for a transformation scheme of an urban power distribution network.
Background
With the abundance of power load and the improvement of power supply quality requirements, urban power distribution networks have become one of the key factors restricting the economic and social development of China. Meanwhile, DG (distributed generation) with gradually improved permeability, namely a distributed power supply, brings uncertainty influence and puts higher requirements on the structure and performance of the urban power distribution network.
At the present stage, the scheme for transforming the urban power distribution network can be mainly summarized into three aspects: the method comprises the steps of upgrading an alternating current distribution line, adopting medium-voltage direct current distribution and improving the permeability of a distributed power supply, wherein each transformation scheme has respective advantages and limitations. Therefore, how to reasonably and effectively make a comprehensive decision on the urban distribution network transformation scheme becomes a problem to be solved urgently.
The comprehensive decision problem of the urban distribution network transformation scheme is an evaluation problem, and comprises the steps of establishing comprehensive evaluation indexes, and performing comprehensive evaluation and sequencing on the transformation scheme by using a proper evaluation method. The comprehensive decision research considering the distribution network transformation scheme containing DGs mainly has two difficulties, namely, whether the distribution power supply in the distribution network is reasonably configured or not lacks a judgment basis, the influence of future load types and proportion changes is not considered, in addition, the fuzziness and uncertainty of preference of a decision maker are not fully considered in an evaluation result method, and the main and objective information in the decision making is not fully utilized, so that the evaluation result is greatly influenced subjectively.
Disclosure of Invention
In order to solve the problems, the technical scheme adopted by the invention is as follows:
the invention provides an evaluation method of an urban distribution network reconstruction scheme, which evaluates the reconstructed urban distribution network according to a comprehensive evaluation index system and reasonably and effectively carries out optimization implementation on different reconstruction schemes, and is characterized by comprising the following steps:
according to special influence factors and uncertain factors in the transformation scheme, a comprehensive evaluation index system comprising a reliability index, a power supply capacity index, an economic index, a DG (distributed generation) receiving capacity index, a disaster resistance capacity index, an adaptability index and a harmony index is constructed for the transformed urban distribution network.
And acquiring and calculating an index result of the modified urban distribution network according to a comprehensive evaluation index system.
And (4) according to the obtained index result, solving subjective weight, objective weight and comprehensive weight of the index by adopting an interval intuitive fuzzy analytic hierarchy process and a CRITIC method.
And obtaining a comprehensive evaluation value by combining a TOPSIS method according to the obtained comprehensive weight, sequencing the transformation schemes according to a comprehensive evaluation value maximization principle, and selecting and implementing the optimal transformation scheme.
The comprehensive evaluation index system comprises a DG acceptance index, the DG maximum admission capacity, the DG annual utilization rate, the voltage fluctuation index and the voltage support index of the urban power distribution network are used as the indexes of the DG acceptance capacity, and a voltage fluctuation index I is definedVF：
Figure BDA0002394851410000021
In the formula ITSIAs a sensitivity factor, NkIs the total number of samples, WkIs the sampling instant tkN is the number of busbars in the network, Wbi△ P represents the change in DG output, V, as the weighting factor for bus ii(tk,P0+ △ P) represents the voltage at the instant when bus i samples for DG output change, △ P+Indicating increased DG output, △ P—Indicating a decrease in DG output.
Defining a voltage support index IVS：
Figure BDA0002394851410000031
In the formula, NiFor the selected number of faults, WFiFor different fault weight coefficients, NkIs the total number of samples, W, after the selected fault FlkRepresenting the sampling instant tkN is the number of busbars in the network, WbiIs the weight coefficient of the bus i, Vi(tk) Is the sampling instant tkThe voltage of (c).
The method for evaluating the urban distribution network transformation scheme provided by the invention can also have the technical characteristics that the comprehensive evaluation index system further comprises the following steps:
evaluating by using a sequential Monte Carlo method by taking the average power failure times, the average power failure time and the power supply availability of the urban distribution network after modification as reliability indexes;
the maximum power supply capacity and the node maximum voltage deviation rate of the urban distribution network after modification are used as power supply capacity indexes;
the method comprises the following steps of adopting net rack annual investment, operation and maintenance cost, annual network loss cost, annual power failure loss cost, investment recovery period and net present value of the urban distribution network after transformation as economic indexes, and utilizing a full life cycle economic assessment method based on a probability method to assess;
the maximum load loss rate, the average load loss rate and the maximum restorable time of the urban distribution network after the transformation after the occurrence of the N-m fault are used as disaster resistance indexes;
the load development adaptability, the environmental adaptability and the system extension margin of the urban distribution network after the transformation are adopted as adaptability indexes;
the influence of the transformed urban distribution network on the safety of the large power grid and the flexibility of operation scheduling are used as coordination indexes.
The method for evaluating the urban distribution network transformation scheme provided by the invention can also have the technical characteristics that for the adaptability index and the harmony index, a Delphi method is adopted to convert the related qualitative evaluation information into a quantitative score.
The method for evaluating the urban distribution network reconstruction scheme provided by the invention can also have the technical characteristics that the step of solving the subjective weight of each index comprises the following steps:
defining a comprehensive interval intuitive fuzzy judgment matrix R by adopting an interval intuitive fuzzy analytic hierarchy process:
R＝(rij)n×n
wherein
Figure BDA0002394851410000041
Figure BDA0002394851410000042
The preference index represents the comparison of the importance degrees of the index i and the index j by a decision makerThe range of the degree of i is,
Figure BDA0002394851410000043
the degree interval of preference index j when the decision maker compares the importance degree of index i and index j is expressed by
Figure BDA0002394851410000044
Representing the hesitation intervals of the decision maker, all the matrixes R satisfy
Figure BDA0002394851410000045
Calculating the vector α ═ α of the subjective weight of the comprehensive interval intuitive fuzzy judgment matrix R1,α2,…αn]The calculation formula is as follows:
Figure BDA0002394851410000046
calculated weights αiIs an interval intuitive fuzzy number.
The method for evaluating the urban distribution network reconstruction scheme provided by the invention can also have the technical characteristics that the step of solving the objective weight of each index comprises the following steps:
establishing a scheme attribute matrix X according to m reconstruction schemes and n comprehensive evaluation indexesn×mAnd is normalized and then converted into a dimensionless standard matrix Gn×mBy gijRepresents a standard matrix Gn×mThe value of the ith row and the jth column is calculated by the formula:
Figure BDA0002394851410000051
in the formula:
Figure BDA0002394851410000052
wherein x isijRepresentation scheme attribute matrix Xn×mValue of ith row and jth column, max | XiL is a scheme attributeMatrix Xn×mTaking the maximum value of the ith row in the table, wherein p is a coordination coefficient and is 0.1;
adopting CRITIC method, and using different transformation schemes to obtain standard deviation s of same comprehensive evaluation indexiCharacterizing contrast to comprehensively evaluate the correlation coefficient rho between the indexesijAnd (5) representing the conflict, and obtaining a quantitative expression:
Figure BDA0002394851410000053
in the formula, MiThe size of the information amount contained in each index,
Figure BDA0002394851410000054
for the ith quantization index which conflicts with other indexes,
Figure BDA0002394851410000055
is the mean of the i-th index, cov (G)i,Gj) Is a standard matrix Gn×mThe covariance of the ith and j rows in (a);
the vector β ═ β for objective weights is calculated1,β2,…βn]The calculation formula is as follows:
Figure BDA0002394851410000061
the method for evaluating the urban distribution network reconstruction scheme provided by the invention can also have the technical characteristics that the step of solving the objective weight of each index comprises the following steps:
α according to the calculated subjective weightiAnd objective weight βiTo obtain the comprehensive weight wiThe calculation formula is as follows:
Figure BDA0002394851410000062
calculated integrated weight wiIs an interval intuitive fuzzy number.
The method for evaluating the urban distribution network transformation scheme provided by the invention can also have the technical characteristics that the preferred implementation steps specifically comprise the following steps:
calculating to obtain a weighted attribute decision matrix Z according to the calculated comprehensive weight and the standard matrix, wherein Z is [ Z ═ Z [ ]1,Z2,…Zn]The calculation formula is as follows:
Zi＝Giwi
establishing an absolute ideal reference point, and defining a positive ideal scheme as
Figure BDA0002394851410000063
Defining a negative ideal scheme as
Figure BDA0002394851410000064
Using the connecting line of the positive and negative ideal schemes as a reference, and defining the projection of the reconstruction scheme on the reference vector as the closeness CjThe calculation formula is as follows:
Figure BDA0002394851410000071
calculated closeness CjIs an interval direct fuzzy number;
closeness degree CjThe larger the transformation scheme is, the better the transformation scheme is judged;
according to the calculated closeness degree CiDefining a scoring and sorting method using a score function, and assigning a closeness CjConversion to real number ρ (C)j) The calculation formula is as follows:
Figure BDA0002394851410000072
wherein the content of the first and second substances,
Figure BDA0002394851410000073
and
Figure BDA0002394851410000074
respectively represent
Figure BDA0002394851410000075
The lower limit and the upper limit of (c),
Figure BDA0002394851410000076
representing the degree interval of preference for the index i when the decision maker compares the importance degrees of the index i and the index j,
Figure BDA0002394851410000077
and
Figure BDA0002394851410000078
respectively represent
Figure BDA0002394851410000079
The lower limit and the upper limit of (c),
Figure BDA00023948514100000710
representing the degree interval of preference index j when the decision maker compares the importance degrees of index i and index j,
Figure BDA00023948514100000711
and
Figure BDA00023948514100000712
respectively represent
Figure BDA00023948514100000713
The lower limit and the upper limit of (c),
Figure BDA00023948514100000714
representing the hesitation interval of the decision maker.
Real number ρ (C)j) Namely the comprehensive evaluation value of the transformed urban distribution network, namely the real number rho (C)j) The larger the value, the better the modification is judged.
According to the real number rho (C)j) And sorting the transformation schemes according to the value, so as to obtain the optimal transformation scheme, and delivering the optimal transformation scheme to the workers in the technical field for implementation.
Action and Effect of the invention
The method for evaluating the urban distribution network transformation scheme comprehensively considers the characteristics of the transformation of the distribution network and the uncertain influence brought by the DGs, supplements evaluation indexes such as disaster resistance capability, DG receiving capability and the like, has a simple and clear constructed index system and is easy to calculate, and can comprehensively reflect the overall performance of the distribution network transformation scheme from different angles.
According to the evaluation method for the urban distribution network transformation scheme, the comprehensive weight calculation evaluation value obtained by the subjective weight and the objective weight is adopted, so that the preference information of a decision maker can be comprehensively depicted, and objective data can be fully utilized. The improved TOPSIS method is introduced to obtain the comprehensive evaluation result, so that the uncertainty of subjective recognition in decision making is reduced, the identification degree of the evaluation result is improved, and the decision making result is more practical and has more credibility.
Drawings
FIG. 1 is a flow chart of an evaluation method of an embodiment of the invention;
FIG. 2 is a diagram of an IEEE33 node power distribution system in accordance with an embodiment of the present invention;
FIG. 3 is a comprehensive evaluation index system of the urban distribution network transformation scheme according to the embodiment of the invention;
FIG. 4 is a radar chart of a primary index according to an embodiment of the present invention;
FIG. 5 is a comparison of composite estimates for different evaluation methods according to embodiments of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made with reference to the accompanying drawings.
< example >
FIG. 1 is a flow chart of an evaluation method according to an embodiment of the present invention.
As shown in fig. 1, the invention provides an evaluation method for an urban distribution network transformation scheme, which comprises the following steps:
according to special influence factors and uncertain factors in the transformation scheme, a comprehensive evaluation index system comprising a reliability index, a power supply capacity index, an economic index, a DG (distributed generation) receiving capacity index, a disaster resistance capacity index, an adaptability index and a harmony index is constructed for the transformed urban distribution network.
And acquiring and calculating an index result of the modified urban distribution network according to a comprehensive evaluation index system.
Fig. 2 is a diagram of an IEEE33 node power distribution system according to an embodiment of the present invention.
The distribution system shown in fig. 2 is selected to verify the feasibility of the comprehensive decision method for the alternating current/direct current transformation scheme of the distribution network, the rated voltage of the comprehensive decision method is 12.66KV, and the total load is 3175kW + j2300 kvar. Five load nodes from 33 to 37 are newly added, four access line options planned for each load node are represented by dotted lines, and the total load of the system is increased to 4215kW + j2620 kvar. The lines to be upgraded and modified in the original system are represented by thick solid lines, and the lines can avoid the overload problem of the lines after being modified mainly because the operation age or the aging problem can not meet the original power requirement. Four schemes for power grid transformation of the area are obtained through a planning database:
scheme 1: DG planning and alternating current circuit planning transformation only including wind power;
scheme 2: DG planning and alternating current line planning transformation only including photovoltaic;
scheme 3: planning and transformation of DG-contained and AC line;
scheme 4: the method comprises DG planning, direct current transformation of a power grid line and direct current planning of a newly-built line.
Due to the difference of DG installation capacity and position, new load node access position and various reconstruction line modes in the four reconstruction schemes, the whole distribution network rack structure is different.
Fig. 3 is a comprehensive evaluation index system of the urban distribution network transformation scheme according to the embodiment of the invention.
As shown in fig. 3, the average power failure times, the average power failure time and the power supply availability of the modified urban distribution network are used as reliability indexes.
And the maximum power supply capacity and the node maximum voltage deviation rate of the modified urban distribution network are used as power supply capacity indexes.
The annual investment, operation and maintenance cost, annual network loss cost, annual power failure loss cost, investment recovery period and net present value of the transformed urban distribution network are used as economic indexes.
The DG maximum access capacity, the DG annual utilization rate, the voltage fluctuation index and the voltage support index of the urban power distribution network are used as indexes of the DG receiving capacity, and the voltage fluctuation index I is definedVF：
Figure BDA0002394851410000101
In the formula ITSIAs a sensitivity factor, NkIs the total number of samples, WkIs the sampling instant tkN is the number of busbars in the network, Wbi△ P represents the change in DG output, V, as the weighting factor for bus ii(tk,P0+ △ P) represents the voltage at the instant when bus i samples for DG output change, △ P+Indicating increased DG output, △ P—Indicating a decrease in DG output.
Defining a voltage support index IVS：
Figure BDA0002394851410000102
In the formula, NiFor the selected number of faults, WFiFor different fault weight coefficients, NkIs the total number of samples, W, after the selected fault FlkRepresenting the sampling instant tkN is the number of busbars in the network, WbiIs the weight coefficient of the bus i, Vi(tk) Is the sampling instant tkThe voltage of (c).
The maximum load loss rate, the average load loss rate and the maximum restorable time of the urban distribution network after the transformation after the N-m fault occurs are used as disaster resistance indexes.
The load development adaptability, the environmental adaptability and the system extension margin of the urban distribution network after the transformation are adopted as adaptability indexes.
The influence of the transformed urban distribution network on the safety of the large power grid and the flexibility of operation scheduling are used as coordination indexes.
Table 1 shows the calculation results of each index of the power distribution network transformation scheme in the current technical level.
Figure BDA0002394851410000111
Figure BDA0002394851410000121
TABLE 1
Table 2 shows the quantitative parts of some indexes of the power distribution network improvement scheme in the current technical level.
As shown in table 1, due to lack of data in some evaluation indexes, relevant qualitative evaluation information is converted into a quantitative score by using a delphi method in the evaluation process, as shown in table 2.
Figure BDA0002394851410000122
TABLE 2
Aiming at index results obtained by the 4 schemes, an interval intuitive fuzzy analytic hierarchy process and a CRITIC method are adopted to obtain subjective weight, objective weight and comprehensive weight of the 4 schemes.
Defining a comprehensive interval intuitive fuzzy judgment matrix R by adopting an interval intuitive fuzzy analytic hierarchy process:
R＝(rij)n×n
wherein
Figure BDA0002394851410000131
Figure BDA0002394851410000132
Representing the degree interval of preference for the index i when the decision maker compares the importance degrees of the index i and the index j,
Figure BDA0002394851410000133
the degree interval of preference index j when the decision maker compares the importance degree of index i and index j is expressed by
Figure BDA0002394851410000134
Representing the hesitation intervals of the decision maker, all the matrixes R satisfy
Figure BDA0002394851410000135
Calculating the vector α ═ α of the subjective weight of the comprehensive interval intuitive fuzzy judgment matrix R1,α2,…αn]The calculation formula is as follows:
Figure BDA0002394851410000136
calculated weights αiIs an interval intuitive fuzzy number.
Establishing a scheme attribute matrix X according to m reconstruction schemes and n comprehensive evaluation indexesn×mAnd is normalized and then converted into a dimensionless standard matrix Gn×mBy gijRepresents a standard matrix Gn×mThe value of the ith row and the jth column is calculated by the formula:
Figure BDA0002394851410000137
in the formula:
Figure BDA0002394851410000138
wherein x isijRepresentation scheme attribute matrix Xn×mValue of ith row and jth column, max | Xi| is the scheme attribute matrix Xn×mTaking the maximum value of the ith row in the table, wherein p is a coordination coefficient and is 0.1;
adopting CRITIC method, and using different transformation schemes to obtain standard deviation s of same comprehensive evaluation indexiCharacterizing contrast to comprehensively evaluate the correlation coefficient rho between the indexesijAnd (5) representing the conflict, and obtaining a quantitative expression:
Figure BDA0002394851410000141
in the formula, MiThe size of the information amount contained in each index,
Figure BDA0002394851410000142
for the ith quantization index which conflicts with other indexes,
Figure BDA0002394851410000143
is the mean of the i-th index, cov (G)i,Gj) Is a standard matrix Gn×mThe covariance of the ith and j rows in (a);
the vector β ═ β for objective weights is calculated1,β2,…βn]The calculation formula is as follows:
Figure BDA0002394851410000144
α according to the calculated subjective weightiAnd objective weight βiTo obtain the comprehensive weight wiThe calculation formula is as follows:
Figure BDA0002394851410000145
and obtaining a comprehensive evaluation value by combining a TOPSIS method according to the obtained comprehensive weight, sequencing the transformation schemes according to a comprehensive evaluation value maximization principle, and selecting and implementing the optimal transformation scheme.
Calculating to obtain a weighted attribute decision matrix Z according to the calculated comprehensive weight and the standard matrix, wherein Z is [ Z ═ Z [ ]1,Z2,…Zn]The calculation formula is as follows:
Zi＝Giwi
establishing an absolute ideal reference point, and defining a positive ideal scheme as
Figure BDA0002394851410000151
Defining a negative ideal scheme as
Figure BDA0002394851410000152
Using the connecting line of the positive and negative ideal schemes as a reference, and defining the projection of the reconstruction scheme on the reference vector as the closeness CjThe calculation formula is as follows:
Figure BDA0002394851410000153
calculated closeness CjIs an interval direct fuzzy number;
closeness degree CjThe larger the transformation scheme is, the better the transformation scheme is judged;
according to the calculated closeness degree CiDefining a scoring and sorting method using a score function, and assigning a closeness CjConversion to real number ρ (C)j) The calculation formula is as follows:
Figure BDA0002394851410000154
in the formula (I), the compound is shown in the specification,
Figure BDA0002394851410000155
and
Figure BDA0002394851410000156
respectively represent
Figure BDA0002394851410000157
The lower limit and the upper limit of (c),
Figure BDA0002394851410000158
representing the degree interval of preference for the index i when the decision maker compares the importance degrees of the index i and the index j,
Figure BDA0002394851410000159
and
Figure BDA00023948514100001510
respectively represent
Figure BDA00023948514100001511
The lower limit and the upper limit of (c),
Figure BDA00023948514100001512
representing the degree interval of preference index j when the decision maker compares the importance degrees of index i and index j,
Figure BDA00023948514100001513
and
Figure BDA00023948514100001514
respectively represent
Figure BDA00023948514100001515
The lower limit and the upper limit of (c),
Figure BDA00023948514100001516
representing the hesitation interval of the decision maker.
Real number ρ (C)j) Namely the comprehensive evaluation value of the transformed urban distribution network, namely the real number rho (C)j) The larger the value, the better the modification is judged.
And table 2 shows the comprehensive evaluation values of the urban distribution network after being modified by different modification schemes.
Figure BDA00023948514100001517
Figure BDA0002394851410000161
TABLE 2
As shown in table 2, the comprehensive evaluation value of the scheme 3 is the highest, and it can be seen that, in the current economic and technical level, an ac reconstruction method using multiple distributed power supplies is the optimal choice for the existing urban distribution network reconstruction scheme, but the current dc reconstruction method has a great disadvantage. Among the 4 schemes, scheme 3 should be selected to be implemented by a worker skilled in the art.
FIG. 4 is a first level index radar chart of an embodiment of the present invention.
As shown in fig. 4, in order to analyze the merits of the ac and dc reconstruction schemes more precisely, a radar map of each primary index score is drawn according to the calculation result.
Analyzing the influence of alternating current and direct current transformation:
comparing the scheme 3 with the scheme 4, it can be known that, in the current technical level, the alternating current transformation scheme is obviously superior to the direct current transformation scheme in terms of reliability, economy, adaptability and coordination, and the main reasons are that the fault rate of power electronic equipment such as a current converter and the like at the current stage is high and the equipment price is higher. Meanwhile, because the high-voltage distribution network and the load are more in an alternating current form at the present stage, the direct current transformation scheme has certain defects in the aspect of coordination. However, compared with the alternating current transformation scheme, the direct current transformation scheme has more outstanding performance in the indexes of power supply capacity, DG access capacity and disaster resistance capacity, and the direct current transformation scheme is mainly suitable for the access of DGs due to the fact that a direct current system is large in transmission capacity and high in power supply efficiency. Generally, in the current-stage urban network reconstruction scheme, the alternating current reconstruction scheme is superior to the direct current reconstruction scheme.
Analysis of DG effect on transformation:
comparing the analysis scheme 1 with the analysis scheme 2, the scheme 1 has less reconstruction of a line than the scheme 2, and has larger DG acceptance capacity and better network loss and voltage index. As can be seen from fig. 4, in addition to the economical efficiency, the scheme 1 is superior to the scheme 2 in all aspects. The reason that the wind power has priority in distribution network transformation is that the wind power output is more consistent with the load matching degree in time sequence, and the daily output of the wind power is higher under most conditions. For the scheme 3 of collaborative reconstruction of wind power and photovoltaic, the capability of accepting the distributed power supply is stronger, and the indexes such as loss reduction, reliability and power supply capability are better than the reconstruction scheme only containing a single distributed power supply. The main reason is that better load matching performance is obtained by wind-light complementation, and better benefit is achieved. This shows that in the later distribution network reconstruction, the wind-solar collaborative planning reconstruction is the optimal choice.
In order to further illustrate the flexibility and the practicability of the evaluation method of the urban distribution network transformation scheme provided by the invention, the four alternating current/direct current transformation schemes are evaluated by respectively adopting an analytic hierarchy process, a CRITIC method, a fuzzy comprehensive decision method and the method, the sensitivity η of each evaluation method is calculated according to the score of each evaluated scheme, and the calculation formula of the sensitivity is as follows:
Figure BDA0002394851410000171
in the formula: ρ (C)j)maxFor the evaluation result of the optimum solution, ρ (C)j)minThe sensitivity η is larger, the discrimination of the evaluation method to different modification schemes is judged to be larger.
Table 3 shows the combined evaluation values and sensitivities for the different evaluation methods.
Figure BDA0002394851410000172
Figure BDA0002394851410000181
TABLE 3
FIG. 5 is a comparison of composite estimates for different evaluation methods according to embodiments of the present invention.
As shown in fig. 5 and table 3, the sensitivity of the evaluation result of each scheme obtained by the method of the present invention is 25.68%, which is much higher than that of the other three methods, so that the evaluation method of the urban distribution network transformation scheme provided by the method of the present invention has a better engineering application prospect.
Examples effects and effects
The method for evaluating the urban distribution network transformation scheme comprehensively considers the characteristics of the transformation of the distribution network and the uncertain influence brought by the DGs, supplements evaluation indexes such as disaster resistance capability, DG receiving capability and the like, has a simple and clear constructed index system and is easy to calculate, and can comprehensively reflect the overall performance of the distribution network transformation scheme from different angles.
According to the evaluation method for the urban distribution network transformation scheme, the comprehensive weight calculation evaluation value obtained by the subjective weight and the objective weight is adopted, so that the preference information of a decision maker can be comprehensively depicted, and objective data can be fully utilized. The improved TOPSIS method is introduced to obtain the comprehensive evaluation result, the uncertainty of subjective understanding in decision making is reduced, the sensitivity of the evaluation result is improved, the decision making result is more practical and has more credibility, and compared with the existing evaluation method, the method has better engineering application prospect.
The present invention is not limited to the above embodiments, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions are all covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (7)

1. The utility model provides an evaluation method of urban distribution network transformation scheme, according to comprehensive evaluation index system, assesses the urban distribution network after the transformation, rationally effectively carries out preferred implementation to different transformation schemes, which is characterized in that, includes the following steps:
the system construction step: according to special influence factors and uncertain factors in the reconstruction scheme, for the reconstructed urban distribution network, constructing a set of comprehensive evaluation index system comprising a reliability index, a power supply capacity index, an economic index, a DG receiving capacity index, a disaster resistance capacity index, an adaptability index and a harmony index, and acquiring an index result of the reconstructed urban distribution network through collection and calculation according to the comprehensive evaluation index system;
a weight obtaining step: according to the obtained index result, an interval intuitive fuzzy analytic hierarchy process and a CRITIC method are adopted to obtain subjective weight, objective weight and comprehensive weight of the index result;
the preferred implementation steps are as follows: obtaining a comprehensive evaluation value by combining a TOPSIS method according to the obtained comprehensive weight, sequencing the transformation schemes according to a comprehensive evaluation value maximization principle, and selecting and implementing the optimal transformation scheme;
wherein, the healdThe combined evaluation index system comprises a DG admission capacity index, the DG maximum admission capacity, the DG annual utilization rate, the voltage fluctuation index and the voltage support index of the urban distribution network are adopted as the DG admission capacity index, and a voltage fluctuation index I is definedVF：
Figure FDA0002394851400000011
In the formula ITSIAs a sensitivity factor, NkIs the total number of samples, WkIs the sampling instant tkN is the number of busbars in the network, Wbi△ P represents the change in DG output, V, as the weighting factor for bus ii(tk,P0+ △ P) represents the voltage at the instant when bus i samples for DG output change, △ P+Indicating increased DG output, △ P—Represents a decrease in DG output;
defining a voltage support index IVS：
Figure FDA0002394851400000021
In the formula, NiFor the selected number of faults, WFiFor different fault weight coefficients, NkIs the total number of samples, W, after the selected fault FlkRepresenting the sampling instant tkN is the number of busbars in the network, WbiIs the weight coefficient of the bus i, Vi(tk) Is the sampling instant tkThe voltage of (c).
2. The method for evaluating the urban distribution network improvement scheme according to claim 1, wherein the system construction step specifically comprises:
the average power failure times, the average power failure time and the power supply availability of the urban distribution network after the transformation are used as the reliability indexes, and a sequential Monte Carlo method is used for evaluating;
the maximum power supply capacity and the node maximum voltage deviation rate of the modified urban distribution network are used as the power supply capacity indexes;
adopting the net rack annual investment, operation and maintenance cost, annual network loss cost, annual power failure loss cost, investment recovery period and net present value of the transformed urban distribution network as the economic indexes, and utilizing a full life cycle economic assessment method based on a probability method to assess;
the maximum load loss rate, the average load loss rate and the maximum restorable time of the modified urban distribution network after the N-m fault occurs are used as the disaster-resistant capability indexes;
adopting the load development adaptability, the environmental adaptability and the system extension margin of the modified urban distribution network as the adaptability indexes;
and adopting the influence of the transformed urban distribution network on the safety of the large power grid and the flexibility of operation scheduling as the harmony index.
3. The method for evaluating the urban distribution network improvement scheme according to claim 1, wherein:
and for the adaptability index and the harmony index, converting related qualitative evaluation information into a quantitative score by adopting a Delphi method.
4. The method for evaluating an urban distribution network modification scheme according to claim 1, wherein the step of obtaining the subjective weight comprises:
defining a comprehensive interval intuitive fuzzy judgment matrix R by adopting an interval intuitive fuzzy analytic hierarchy process:
R＝(rij)n×n
wherein
Figure FDA0002394851400000031
Figure FDA0002394851400000032
Representing the degree interval of preference for the index i when the decision maker compares the importance degrees of the index i and the index j,
Figure FDA0002394851400000033
the degree interval of preference index j when the decision maker compares the importance degree of index i and index j is expressed by
Figure FDA0002394851400000034
The hesitation degree interval of the decision maker is represented, and R satisfies
Figure FDA0002394851400000035
Calculating [ α ] a vector α of the subjective weight of the integrated interval intuitive fuzzy determination matrix R1,α2,…αn]The calculation formula is as follows:
Figure FDA0002394851400000036
calculated weights αiIs an interval intuitive fuzzy number.
5. The method according to claim 1, wherein the obtaining the objective weight specifically comprises:
establishing a scheme attribute matrix X according to the m reconstruction schemes and the n comprehensive evaluation indexesn×mAnd is normalized and then converted into a dimensionless standard matrix Gn×mBy gijRepresenting the standard matrix Gn×mThe value of the ith row and the jth column is calculated by the formula:
Figure FDA0002394851400000041
in the formula:
Figure FDA0002394851400000042
wherein x isijRepresenting the scheme attribute matrix Xn×mValue of ith row and jth column, max | Xi| is the scheme attribute matrix Xn×mTaking the maximum value of the ith row in the table, wherein p is a coordination coefficient and is 0.1;
adopting CRITIC method, and using standard deviation s of same comprehensive evaluation index of different transformation schemesiCharacterizing contrast and using correlation coefficient rho between the comprehensive evaluation indexesijAnd (5) representing the conflict, and obtaining a quantitative expression:
Figure FDA0002394851400000043
in the formula, MiThe size of the information amount contained in each index,
Figure FDA0002394851400000044
for the ith quantization index which conflicts with other indexes,
Figure FDA0002394851400000045
is the mean of the i-th index, cov (G)i,Gj) Is the standard matrix Gn×mThe covariance of the ith and j rows in (a);
calculating the vector β ═ β of the objective weight1,β2,…βn]The calculation formula is as follows:
Figure FDA0002394851400000051
6. the method for evaluating an urban distribution network improvement scheme according to claim 1, wherein solving the comprehensive weight specifically comprises:
α according to the subjective weight obtained by calculationiAnd the objective weight βiObtaining the said comprehensive weight wiThe calculation formula is as follows:
Figure FDA0002394851400000052
the calculated comprehensive weight wiIs an interval intuitive fuzzy number.
7. The evaluation method for the power distribution network improvement scheme according to claim 1, wherein the preferable implementation steps specifically comprise the following steps:
calculating to obtain a weighted attribute decision matrix Z according to the calculated comprehensive weight and the standard matrix, wherein Z is [ Z ═ Z1,Z2,…Zn]The calculation formula is as follows:
Zi＝Giwi
establishing an absolute ideal reference point, and defining a positive ideal scheme as
Figure FDA0002394851400000053
Defining a negative ideal scheme as
Figure FDA0002394851400000054
Using the connecting line of the positive and negative ideal schemes as a reference, and defining the projection of the transformation scheme on the reference vector as a proximity CjThe calculation formula is as follows:
Figure FDA0002394851400000061
the calculated closeness CjIs an interval direct fuzzy number;
the closeness degree CjThe larger the transformation scheme is, the better the transformation scheme is judged to be;
according to the calculated closeness degree CiDefining a scoring and sorting method using a scoring function, and assigning the closeness
Figure FDA0002394851400000062
Conversion to real number ρ (C)j) The calculation formula is as follows:
Figure FDA0002394851400000063
wherein the content of the first and second substances,
Figure FDA0002394851400000064
and
Figure FDA0002394851400000065
respectively represent
Figure FDA0002394851400000066
The lower limit and the upper limit of (c),
Figure FDA0002394851400000067
representing the degree interval of preference for the index i when the decision maker compares the importance degrees of the index i and the index j,
Figure FDA0002394851400000068
and
Figure FDA0002394851400000069
respectively represent
Figure FDA00023948514000000610
The lower limit and the upper limit of (c),
Figure FDA00023948514000000611
representing the degree interval of preference index j when the decision maker compares the importance degrees of index i and index j,
Figure FDA00023948514000000612
and
Figure FDA00023948514000000613
respectively represent
Figure FDA00023948514000000614
The lower limit and the upper limit of (c),
Figure FDA00023948514000000615
representing the hesitation interval of the decision maker,
the real number ρ (C)j) Namely the reconstructed comprehensive evaluation value of the urban distribution network, namely the real number rho (C)j) The larger the value is, the better the transformation scheme is judged to be;
according to the real number ρ (C)j) And sequencing the transformation schemes according to the value, so as to obtain the optimal transformation scheme, and delivering the optimal transformation scheme to the implementation of workers in the technical field.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112348351A (en) * 2020-11-05 2021-02-09 招商局重庆交通科研设计院有限公司 Method for evaluating seismic reinforcement priority of bridge in road network
CN112713599A (en) * 2020-12-17 2021-04-27 郑州轻工业大学 Comprehensive evaluation method for voltage supporting capability of distributed power supply
CN112819279A (en) * 2020-12-31 2021-05-18 国网山东省电力公司聊城供电公司 Planning evaluation method and system for expansion adaptability of distributed energy and power distribution network
CN113177705A (en) * 2021-04-23 2021-07-27 天津大学 Evaluation method and device for miniature photovoltaic or wind energy collector
CN113762751A (en) * 2021-08-30 2021-12-07 国网冀北电力有限公司电力科学研究院 Unit power regulation parameter weight determination method and device
CN113988694A (en) * 2021-11-11 2022-01-28 国网天津市电力公司 Urban power grid comprehensive evaluation method under weak connection high-proportion new energy access
CN115392795A (en) * 2022-10-27 2022-11-25 国网浙江省电力有限公司宁波市北仑区供电公司 Transformation assessment method, system, equipment and medium for power distribution network

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107239900A (en) * 2017-06-01 2017-10-10 陕西学前师范学院 Based on the Undergraduate Thesis quality evaluating method of cloud model can be opened up
CN107482626A (en) * 2017-08-17 2017-12-15 广东电网有限责任公司惠州供电局 A kind of regional power grid key node recognition methods
CN109146184A (en) * 2018-08-28 2019-01-04 成都信息工程大学 Based on the Interval Intuitionistic Fuzzy multiple attributive decision making method for improving entropy and scoring function
CN109389332A (en) * 2018-12-22 2019-02-26 中铁十八局集团有限公司 Evaluation method is configured based on combination weighting-improved grey conjunction analytic method Bridge Erector
CN109670660A (en) * 2017-10-13 2019-04-23 南京航空航天大学 A kind of fleet dynamic air defense threat estimating method based on intuitionistic fuzzy TOPSIS
CN110232518A (en) * 2019-06-11 2019-09-13 西北工业大学 A kind of intimidation estimating method based on three decisions
CN110264032A (en) * 2019-05-08 2019-09-20 上海电力学院 A kind of acquisition methods of direct current distribution Plan mode result
CN110458463A (en) * 2019-08-15 2019-11-15 西南交通大学 A kind of electric power Internet of Things safety evaluation method based on Interval Intuitionistic Fuzzy decision
CN110458479A (en) * 2019-08-23 2019-11-15 中国南方电网有限责任公司 A kind of new energy field technological achievement is converted into the potential evaluation method of technical standard

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107239900A (en) * 2017-06-01 2017-10-10 陕西学前师范学院 Based on the Undergraduate Thesis quality evaluating method of cloud model can be opened up
CN107482626A (en) * 2017-08-17 2017-12-15 广东电网有限责任公司惠州供电局 A kind of regional power grid key node recognition methods
CN109670660A (en) * 2017-10-13 2019-04-23 南京航空航天大学 A kind of fleet dynamic air defense threat estimating method based on intuitionistic fuzzy TOPSIS
CN109146184A (en) * 2018-08-28 2019-01-04 成都信息工程大学 Based on the Interval Intuitionistic Fuzzy multiple attributive decision making method for improving entropy and scoring function
CN109389332A (en) * 2018-12-22 2019-02-26 中铁十八局集团有限公司 Evaluation method is configured based on combination weighting-improved grey conjunction analytic method Bridge Erector
CN110264032A (en) * 2019-05-08 2019-09-20 上海电力学院 A kind of acquisition methods of direct current distribution Plan mode result
CN110232518A (en) * 2019-06-11 2019-09-13 西北工业大学 A kind of intimidation estimating method based on three decisions
CN110458463A (en) * 2019-08-15 2019-11-15 西南交通大学 A kind of electric power Internet of Things safety evaluation method based on Interval Intuitionistic Fuzzy decision
CN110458479A (en) * 2019-08-23 2019-11-15 中国南方电网有限责任公司 A kind of new energy field technological achievement is converted into the potential evaluation method of technical standard

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
于倩雯 等: "基于区间直觉模糊TOPSIS法的节水灌溉工程方案优选", 《节水灌溉》 *
朱天曈 等: "基于改进 TOPSIS 法和德尔菲—熵权综合权重法的电网规划方案综合决策方法", 《电力系统保护与控制》 *
罗志刚 等: "基于区间直觉模糊理论的直流配网规划方案综合决策", 《电工技术学报》 *
谭吉玉 等: "基于 TOPSIS 的区间直觉模糊数排序法", 《控制与决策》 *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112348351A (en) * 2020-11-05 2021-02-09 招商局重庆交通科研设计院有限公司 Method for evaluating seismic reinforcement priority of bridge in road network
CN112348351B (en) * 2020-11-05 2022-06-10 招商局重庆交通科研设计院有限公司 Method for evaluating seismic reinforcement priority of bridge in road network
CN112713599A (en) * 2020-12-17 2021-04-27 郑州轻工业大学 Comprehensive evaluation method for voltage supporting capability of distributed power supply
CN112713599B (en) * 2020-12-17 2023-03-03 郑州轻工业大学 Comprehensive evaluation method for voltage supporting capability of distributed power supply
CN112819279A (en) * 2020-12-31 2021-05-18 国网山东省电力公司聊城供电公司 Planning evaluation method and system for expansion adaptability of distributed energy and power distribution network
CN113177705A (en) * 2021-04-23 2021-07-27 天津大学 Evaluation method and device for miniature photovoltaic or wind energy collector
CN113762751A (en) * 2021-08-30 2021-12-07 国网冀北电力有限公司电力科学研究院 Unit power regulation parameter weight determination method and device
CN113988694A (en) * 2021-11-11 2022-01-28 国网天津市电力公司 Urban power grid comprehensive evaluation method under weak connection high-proportion new energy access
CN115392795A (en) * 2022-10-27 2022-11-25 国网浙江省电力有限公司宁波市北仑区供电公司 Transformation assessment method, system, equipment and medium for power distribution network

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