Study Of The Power Quality Comprehensive Evaluation Method

The level of power quality closely related to our life, especially for a high degreeof automation and power quality sensitive industrial users.A high level of powerquality is directly related to the economic efficiency of enterprises.The pollution ofelectric power system is more and more serious with more and more putting in of newelectronic equipment.It is basic conditions for power pollution control to evaluatepower quality scientifically and effectively.It is important not only for improving thequality of power supply system, but also for the whole national economy.This paper elaborated the concept of power quality and related indicatorscombining power quality standards at home and abroad.Then,the power qualityevaluation system was introduced, and the existing power quality assessment methodsand multiple individual indicators index comprehensive evaluation methods werestudied.Harmonic similarity evaluation method based on fuzzy selection and proximityis proposed for the assessment of individual indicators.Firstly,the index sequencebetween the evaluation object and the known object were compared andanalyzed,Then, the proximity indicators were used to evaluate the results, which werecombined with fuzzy nearness and grey relational analysis,Acquire the membershipof assessment object for the optimal level and next level to analyze the purpose of theharmonic pollution situation.A dynamic weight based data envelopment analysis (DEA) evaluation method isproposed for a comprehensive assessment of power quality.A power qualitycomprehensive evaluation index system was established, according to the basicprinciple of data envelopment analysis (DEA),the power quality indicators deviationof the measured data with the national standard as input index, the assessment level ofpower quality problems as output indicators.using data envelopment analysis methodto analyze decision making units (DMU), get the efficiency value of decision makingunits, through analyze the units efficiently, get the assessment grade of evaluationunit.Using data envelopment analysis (DEA) method to avoid the drawbacks effect of selected weights on the power quality evaluation.By numerical example, this methodis objective, accurate and have a good suitability at the same time.