Secondary Control for Islanded Microgrids

This chapter introduces concepts, characteristics, advantages, and drawbacks of different secondary control approaches for islanded microgrids. First, multilayer hierarchical control is reviewed, defining the main features and control objectives of each control layer. Second, centralized and distributed control approaches (and the best-known distributed techniques: averaging and consensus) are presented. The sections include the main equations and aspects about the corresponding communications schemes. Then, the impacts of communications issues over these techniques are analyzed. Third, control with no communication is discussed considering its pros and cons. Finally, experimental demonstrations in a laboratory microgrid are presented to analyze the characteristics of the approaches described. The chapter concludes with key findings and remarks.