Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Reactive Power Control Algorithm of Grid-Connected Inverter at the Point of Common Coupling With Compensation of Series and Parallel Impedances
Authors Cheol-Young Heo ; Seung-Ho Song ; Yong-Rae Kim
Page pp.92-99
ISSN 1229-2214
Keywords Grid connected inverter system; Reactive power control; PCC (Point of Common Coupling); Parallel impedance; Series impedance
Abstract Due to space and geographical constraints, the power source may be located outside the island area, resulting in the considerable length of transmission line. In these cases, when an active power is transmitted, unexpected reactive power is generated at a point of common coupling (PCC). Unlike the power transmitted from the power generation source, the reactive power adversely affects the system. This study proposes a new algorithm that controls reactive power at PCC. Causes of reactive power errors are separated into parallel and series components, which allows the algorithm to compensate the reactive current of the inverter output and control reactive power at the PCC through calculations from the impedance, voltage, and current. The proposed algorithm has economic advantages by controlling the reactive power with the inverter of the power source itself, and can flexibly control power against voltage and output variations. Through the simulation, the algorithm was verified by implementing a power source of 3 [kVA] capacity connected to the low voltage system and of 5 [MVA] capacity connected to the extra-high voltage system. Furthermore, a power source of 3 [kVA] capacity inverter is configured and connected to a mock grid, then confirmed through experiments.