8. Decentralized Method for Islanded Operation Mode

In series-type microgrid, the synchronization and power balance of distributed generators become two new issues that need to be addressed urgently. To that end, an f − P∕Q droop control is firstly introduced in this chapter, which is capable to achieve power balance under both resistive-inductive and resistive-capacitive loads autonomously. However, the f − P∕Q droop control for series-type microgrid has the problem of multiple equilibrium points. Then, this chapter introduces a new decentralized power sharing control scheme to address this problem. The uniqueness of equilibrium point and its small signal stability are proved. Besides, the power factor angle droop control is introduced to suit for any types of loads in islanded modes. Finally the feasibility of the methods is verified by simulation.