Method for evaluating power quality comprehensively based on the Vague sets and the improved technique for order preference by similarity to ideal solution and application thereof

Abstract

The invention discloses a method for evaluating power quality comprehensively based on the Vague sets and the improved technique for order preference by similarity to ideal solution and the application thereof. The method consists of the steps of: monitoring the common connection points of an offshore wind power plant, and acquiring the simulation data of power quality indicators; determining the weight vectors (i)W( / i) of the power quality indicators of each evaluation object; indicating the scores of the indicators of each evaluation object with Vague values; determining an absolute positive ideal solution and an absolute negative ideal solution; calculating the distance between each evaluation object and the absolute positive ideal solution and the distance between each evaluation object and the absolute negative ideal solution and the relative closeness of each evaluation object, and comprehensively evaluating and sequencing the power quality according to the calculated results. By means of this invention, the weights are determined more objectively and less subjectively, and in the meantime, the weight of indicators and the weights of the true membership function, the false membership function and the abstention part of the indicators are considered, so that the evaluation result can be closer to the actual situation. The method plays a very significant role in enhancing the transparency of the power market and improving the power supply quality of the power system.

Description

technical field [0001] The invention relates to a comprehensive evaluation method of power quality based on Vague set and improved approximation ideal solution and its application, which belongs to the field of comprehensive evaluation of electrical engineering and power quality. Background technique [0002] As a green and renewable resource, wind energy has been widely valued all over the world. In recent years, offshore wind power has developed rapidly and has the advantages of high wind speed, large power generation and less interference. However, the fluctuation, intermittent and randomness of wind speed, wake flow, turbulent flow, fan tower shadow effect, etc. will cause power fluctuations, which will affect the power quality. It will affect and interfere with the power network. In the electricity market environment, the price of electric energy based on quality, high quality and high price, and evaluation point assessment rewards and punishments require people to pa...

AI Technical Summary

Problems solved by technology

However, many of the existing methods for determining weights do not consider the uncertainty caused by the differences in expert knowledge, which makes the results more subjective

Compared with the subjective evaluation method, the objective evaluation method has the characteristics of more objective evaluation results. Many intelligent methods require the training sample data to be large enough to obtain an accurate model, and then use the existing model to evaluate other data, but the actual There are often not enough data in the data, so the evaluation results are often different from the actual situation.

There are also some objective evaluation methods that do not consider the characteristics of the power quality indicators of different evaluation objects, resulting in the evaluation results not in line with the actual situation.

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