The Transactions of the Korean Institute of Power Electronics (전력전자학회논문지)

The Korean Institute of Power Electronics (전력전자학회)
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Reactive Power Control Algorithm of Grid-Connected Inverter at the Point of Common Coupling With Compensation of Series and Parallel Impedances

직병렬 임피던스 보상을 통한 계통 연계 분산전원 인버터의 PCC 무효전력 제어 알고리즘

  • Heo, Cheol-Young (Dept. of Control & Instrumentation Engineering Team, Kwangwoon University) ;
  • Song, Seung-Ho (Dept. of Electronic Engineering, Kwangwoon University) ;
  • Kim, Yong-Rae (Dept. of Control & Instrumentation Engineering Team, Kwangwoon University)
  • Received : 2021.10.06
  • Accepted : 2021.11.30
  • Published : 2022.04.20
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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.

Keywords

Acknowledgement

이 논문은 2021년도 광운대학교 우수연구자 지원사업, 산업통상자원부(MOTIE), 한국에너지기술평가원(KETEP)의 지원을 받아 수행한 연구과제입니다. (No. 20193710100061)

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