Optimal Reactive Power Planning in Active Distribution Systems for Steady-state and Transient Characteristics Improvement

Numerous operational issues including voltage deviation and instability arise in distribution networks with insufficient reactive support. Static issues have been widely studied for years, and some dynamic ones are recently gaining attention due to the proliferation of distributed generation (DG). In this paper, a two-step reactive compensation planning procedure is proposed to address these challenges. In the first step, passive compensators are optimally sited and sized using a metaheuristic algorithm in order to improve steady-state indices including power efficiency, voltage profile, and static voltage stability. In the second step, a static synchronous compensator (Statcom) is located in the network to obtain the fastest voltage recovery at the terminals of DG units. The proposed methodology is applied to a 69-bus distribution system and the operational indices before and after the optimization are compared.