Power quality comprehensive evaluation and sensitivity analysis based on fuzzy analytical hierarchy process

Power quality represents an important component of power system operating performance. In the existing methods for power quality evaluation,the weights for various evaluation indices are usually specified by domain experts,while the knowledge and experience of experts are better described by fuzzy sets. Given this background,the well-established fuzzy analytical hierarchy process( FAHP) is applied to evaluate power quality in specified monitoring buses,and a complementary judgment matrix based on triangular fuzzy numbers employed. Then,the expected values of triangular fuzzy numbers are employed to define the weights of indexes. A sensitivity analysis method is next presented to examine the impacts of the values and weights of indices on the comprehensive evaluation results. And the sensitivity intervals which may lead to the change of the sorting results of power quality evaluation are obtained and can help both power supply companies and customers to respectively make reasonable decisions on supplying and consuming electricity. Finally,a distribution system with a 10 kV voltage level is served for demonstrating the developed method.