Cloud Model Based Power Quality Comprehensive Assessment Of Distribution System With Microgrids

Driven by the intensifying energy problem crisis and the encouraging policy of energy conservation and emissions reduction, the combination process of traditional grid and micro-grid has sped up while the importance of micro-grid is increasing. Meanwhile, the power market makes its own breakthrough, in this way, the comprehensive evaluation of power quality would play a more and more important role.In this paper, after describing the conception of power quality, a scientific division on each power quality indicators has been made to establish a comprehensive evaluation power quality system. Then, this paper lays emphasis on analyzing the differences of power quality between distribution system with microgrids and traditional grid after the brief description of micro-grid, studying the influence on the power quality due to the distribution system. And a new power quality comprehensive assessment method of distribution system with microgrids based on cloud model has been proposed. In this approach, taking both the subjective and objective factors into consideration, the improved multi-level interactive decision-making mode, which is combined with the characteristics of distribution system with microgrids, is chosen to determine the weights of different indexes in order to guarantee the correctness and scientificity. Standard normal cloud model is adopted to deal with the randomness and fuzziness of power quality comprehensive assessment indicators, through quantifying qualitative indicators.After proposed this new method, the results of one typical case in this paper, show the effectiveness and superiority of the proposed approach.