Load frequency control of multi-microgrid using energy storage system

Control of active power and frequency in a power system is referred to as load frequency control (LFC). A linear combination of tie line power between interconnected system and frequency deviations, defined as area control error (ACE), is regulated to zero by LFC such that frequency and tie-line power errors are forced to zeros and a balance is achieved between generation and load. This paper presents an investigation on the LFC of multi-microgrid (MMG) using energy storage system (ESS). The tie-line connected MMG system consists of two microgrids, each made up of a synchronous generator, a PV source, a wind power system, ESS and load. Control strategies are developed based on both, frequency deviation and ACE, to regulate the ESS output. A performance index is defined for comparative assessment of control strategies. Effectiveness of the frequency control strategies is studied through simulation.