An Integrated Compensation Algorithm for PCC Voltage Fluctuation and Unbalance with Variable Limit of Positive and Negative Sequence Currents

  • Im, Ji-Hoon (Energy New Business Laboratory, KEPCO Research Institute) ;
  • Song, Seung-Ho (Dept. of Electrical Engineering, Kwangwoon University) ;
  • Cho, Sung-Min (Energy New Business Laboratory, KEPCO Research Institute)
  • Received : 2015.12.31
  • Accepted : 2016.12.12
  • Published : 2017.03.01


This paper proposes a point of common coupling (PCC) voltage compensation algorithm using a current limitation strategy for use in distributed generation (DG). The proposed strategy maintains the PCC voltage by prioritizing currents when an output current reference is larger than the current capacity of the power condition system (PCS) of the DG. With this strategy, the DG outputs the active current, reactive current, and the negative sequence current. The DG uses the reactive current for maintaining the PCC voltage within a normal range; the negative sequence current is used for reducing the PCC voltage unbalance. The proposed method was verified using PSIM simulation and experimental results.


Supported by : Korea Institute of Energy Technology Evaluation and Planning (KETEP)


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