Single‐Phase Alternating‐Current (ac) DERs

In a single‐phase ac distributed energy resource (DER) application, the power electronic converter is used to exchange the power between a dc side and an ac side. The ac side can be a load, a grid, or a microgrid. This chapter studies the control system objectives and challenges pertaining to such a system. It discusses scenarios and policies where the inverter can provide quick grid support within its local control system. The chapter also discusses how to efficiently build and design a current feedback loop for a grid‐connected inverter. It explores how the controller can provide ac grid support functions. DERs may exist in many forms such as energy storage (battery), solar, and wind. They may be used to build an ac micro‐grid, a dc micro‐grid or a hybrid micro‐grid with both ac and ac subsystems.