Control of the Neutral Leg in Three-Phase Four-Wire Inverter Using Proportional-Resonant Controller

PR 제어기를 이용한 3상 4선식 인버터 Neutral Leg 제어 방법

  • Han, Jungho (Dept. of Railway Electrical and Signaling Engineering, Seoul National University of Science and Technology) ;
  • Song, Joongho (Dept. of Electrical and Information Engineering, Seoul National University of Science and Technology)
  • Received : 2014.10.21
  • Accepted : 2014.12.17
  • Published : 2015.02.28


In 3-phase 4-wire inverter, the unbalanced loads cause to increase the neutral current which brings the voltage deviation between the split dc-link capacitors to be larger. In order to solve this problem, a neutral leg is provided additively to the ordinary inverter circuit and the associated control methods are devised. This paper proposes a new neutral-leg controller based on a PR controller and shows relatively good performance even under unbalanced linear loads and nonlinear loads. The proposed control strategy illustrates its effectiveness under the various operating conditions through simulation works.


Three-Phase Four-Wire Inverter;Dc-Link Balancing Control;Proportional-Resonant Control


Supported by : 서울과학기술대학교


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