Method for assessing harmonic pollution level on basis of extended cloud similarity and similarity to ideal solution

Abstract

The invention discloses a method for assessing harmonic pollution level on the basis of extended cloud similarity and similarity to ideal solution. The method comprises the following steps: firstly, establishing an assessment index system with total harmonic distortion of voltage and an effective value of harmonic current as indexes; then, integrating weight information of multiple experts with a group decision characteristic root method to obtain comprehensive weight of a harmonic pollution level assessing expert group; adopting triangular fuzzy numbers to describe fuzziness of the harmonic pollution level assessing indexes, and performing unified computation on the triangular fuzzy numbers with extended cloud similarity measure; finally, obtaining a reasonable harmonic pollution level assessing result with the method of similarity to ideal solution under the condition of construction of unified benchmark level as well as positive and negative ideal solutions. With adoption of the method, the harmonic pollution level can be assessed comprehensively, harmonic index fluctuation and assessment decision groupment in a period of time are considered, the weight information of multiple experts is integrated better, and the reasonable harmonic pollution level assessing result is obtained.

Description

Technical field [0001] The invention belongs to the field of power systems, and particularly relates to a method for evaluating harmonic pollution levels based on extended cloud similarity and approximation to an ideal solution. Background technique [0002] In recent years, with the large-scale application of non-linear devices such as power electronic equipment, harmonic pollution in the power grid has increased, and harmonics have become a prominent problem in power quality. In order to analyze whether the harmonic pollution of the busbar exceeds the standard, it is necessary to use the harmonic measurement data and the harmonic source location result to comprehensively evaluate the harmonic pollution level of the busbar or area. [0003] At present, there are few research reports on the evaluation of harmonic pollution level, but there are a large number of comprehensive power quality evaluation methods, and they are relatively mature, which provide a certain reference for the ...

AI Technical Summary

Problems solved by technology

Neural network method and genetic algorithm do not require subjective weighting, but the principle is complex and difficult to implement

At the same time, the above evaluation methods only use harmonic voltage as an index to measure the level of harmonic pollution, which fails to fully reflect the level of harmonic pollution

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