Delay-dependent stability of LFC in Microgrid with varying time delays

Load frequency control systems used to rely on dedicated communication links. The deregulation of the electricity market and the emergence of the Microgrids and Smartgrids made the open communication infrastructure an exigent need for future power system. In this case the load frequency control signals will be exchanged through communication network. The communication network is characterized by variable time delay which may lead to system instability. This paper investigates the stability of load frequency control system in islanded micro-grid with the presence of the time delay. The stability analysis is based on solving a set of linear matrix inequalities. Also, the effects of the controller gains and time delay variation rate on the maximum allowable delay bound are investigated.