Research On The Build Of The Power Quality Evaluation System Of Wind Power After Grid Connection

As the growth of the society and the progress of mankind,wind energy,as a clean and reproducible new energy source,has enormous growth prospect and has been more and more extensively used these few years.In the context of the swift growth of wind power,it’s a significant task to increase the power quality after wind power is linkeded with the grid,and it’s also a hard poser to establish a scientific and rational power quality evaluation system for the entire power market.This essay puts forward a more comprehensive and systematic evaluation system to ensure the objectivity of its output results,establish an intelligent system competent of actual-time control and resolve power quality characteristic signals,and bring about actual-time evaluation of power quality,thereby enhancing the safety and stability of the grid system after the area is linked with the grid.Firstly,this article analyzes the voltage deviation,voltage fluctuation,three-phase unbalance,harmonics,flicker and other problems caused by grid-linked power.According to the power quality evaluation index of wind power at home and abroad,the evaluation index is determined and combined Establish an evaluation system.Using the method of simulation analysis,analyze the influence of wind power grid connection on system voltage fluctuation,flicker and harmonics.Secondly,the fuzzy neural network theory is obtained through the combination of fuzzy evaluation theory and BP neural network algorithm,a model for power quality evaluation of wind power grid-linked power is constructed,and fuzzy rules are established.On the basis of the maximum membership theory,the weight matrix is obtained,and the weight of the evaluation power quality characteristic parameters is obtained.The final method of determining the power quality level is the level eigenvalue method.Using python programming to develop the power quality evaluation system,training and expanding the sample data,perform difference processing on the data in the actual calculation example and feedback in the normalization layer,obtain the output evaluation result,and evaluate the result,a comparative study is carried out with the comprehensive evaluation system of wind power grid-linked power quality upon the principle of maximum entropy to demonstrate that the evaluation result of the power quality evaluation system based on fuzzy neural network is more reasonable and reliable.Last but not least,the Fuqiang Wind Farm in Heilongjiang Province is selected as the research object,and the evaluation system put forward in this thesis is further verified by examples,and the corresponding betterment strategy for power quality is put forward through the evaluation results.