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

• Accepted : 2014.12.17
• Published : 2015.02.28
• 20 109

#### Abstract

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.

#### Keywords

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

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#### Acknowledgement

Supported by : 서울과학기술대학교