Island Partition Strategy Based on Entropy Method-Set Pair Analysis for Microgrids

Abstract

The scientific and reasonable island partition of microgrids containing DG is of great practical significance for ensuring the safe switching of microgrid island operation and improving the reliability of microgrid power supply. The existing island partitioning strategies focus on power balance and basic load distribution but often neglect multiple load attributes, resulting in failure to guarantee the reliability of the load power supply with a relatively high comprehensive evaluation level. Therefore, to comprehensively consider the influence of multiple load attributes on islanding, an island partitioning strategy based on entropy method-set pair analysis is proposed for microgrids in this paper. First, the entropy method is used to objectively assign the weights of three indexes of the level of the load, the economic loss of the load power outage and the coefficient of change per unit power. Next, the set pair analysis (SPA) principle is combined with the comprehensive connection degree of the index to determine the comprehensive connection degree of different loads while considering each index, and the connection degree is used as the final island partition power supply recovery coefficient of the load. Finally, the dynamic programming algorithm is used to solve the objective function of island partitioning. The IEEE-69 node system verifies the proposed strategy. The verification results show that compared with the existing methods, the proposed strategy can restore the power supply of the important load more effectively and reduce the economic loss when the load is cut off. The proposed island partitioning strategy shows significant potential in improving the reliability and economy of the power supply for microgrids with important loads, especially for microgrids with complex loads.

Keywords

• Entropy method
• island partition
• microgrid
• set pair analysis