Research on Optimization Method of Short-Circuit Current-Limiting Measures Based on Combination Assignment

Abstract

This paper puts forward a selection principle and an optimization configuration method for short-circuit current-limiting measures to address the increasingly severe short-circuit current-exceeding problem brought about by the high-speed development of large power grids. Firstly, we introduce the function principle and the advantages and disadvantages of various short-circuit current-limiting measures in the power system and give the selection conditions of generalized short-circuit current-limiting measures. Then, we adopt the hierarchical analysis method (AHP) and entropy weighting method (EWM) to evaluate the weights of the indicators of the short-circuit current level, the line-loading level, the active loss, and the economic cost; perform the selection of multiple short-circuit current-limiting schemes after the combination of the assigned weights; and describe the generalized process of engineering used to solve the problem of short-circuit currents exceeding limits. We then provide a generalized process with which to solve the short-circuit current-exceeding problem in engineering. Finally, we take the actual large-scale power grid as an example, propose multiple short-circuit current-limiting schemes for a 220 kV power grid, and carry out the selection of optimal schemes to verify the validity and reliability of the study. The results show that this process plays an important role in controlling the short-circuit current of the power system, maintaining the safe and stable operation of the power system and improving the power system’s grid structure.

Keywords

• large power grids
• short-circuit current-limiting measures
• applicability conditions
• the analytic hierarchy process
• entropy weighted method
• meritocracy