ABSTRACT
This chapter discusses frequency and voltage control through voltage source converters (VSCs) in a microgrid VSC is the key element in a microgrid to interface distributed energy sources. The chapter illustrates the fundamental control structure of a VSC. It presents coordination among converters for real power and reactive power sharing. An alternative name for coordination is primary frequency control and primary voltage control. The chapter also discusses power sharing methods among converters. Droop controls that are applied in synchronous generators and reactive power sharing again find applications in converters. Implementation of droop control depends on the converter control structure. The chapter examines two parallel VSCs, in either grid-connected mode or autonomous mode. It explains a VSC as a controllable voltage source with its abc three-phase voltages controllable. The VSC controls will adjust the three-phase voltage.
