A Fully Distributed Power Dispatch Method for Fast Frequency Recovery and Minimal Generation Cost in Autonomous Microgrids

This paper describes a fully distributed power dispatch method that can achieve fast frequency recovery and minimal generation cost for autonomous microgrids. The method is comprised of two stages. In the first stage, a subgradient-based consensus algorithm is used to recover frequency. The equal increment rate criteria is incorporated into this algorithm to achieve a minimal regulating cost, obtained by economically distributing power among distributed energy resources. Control signals updated with latest local measurements are executed in each iteration step to speed up the frequency recovery procedure. In the second stage, an average consensus algorithm is applied to resolve frequency oscillations caused by measurement errors. Numerical tests are described to demonstrate the validity of the proposed method and its applicability in the presence of communication time delay is discussed.