Analisis Pengaruh Penggunaan Transformator Zig-Zag dalam Mereduksi Harmonisa Urutan Nol

Abstract

In a three-phase distribution system connected to a non-linear load, the resulting zero-sequence or third-harmonic currents can cause power quality problems. Non-linear electric loads produce currents that are not sinusoidal even though the voltage source used is a pure sinusoidal wave. Every periodic wave that is not sine-shaped contains harmonics. Non-linear electrical loads are the cause of high harmonic currents occurring in the electrical system. The purpose of this research is to obtain the integration of a transformer model with a zig-zag connection in reducing zero sequence harmonics and to find out the comparison of the Total Harmonic Distortion (THD) before and after reduction with a zig-zag transformer. This study discusses a method for reducing zero sequence harmonic currents using a zig-zag transformer using three single-phase transformers. The zig-zag connection of the transformer is obtained by connecting the three windings of a single-phase transformer in a special way. The zig-zag transformer provides a path for the current in the neutral conductor to return to the load. To determine the performance of a zig-zag transformer in reducing zero-sequence harmonic currents and to reduce currents in the neutral conductor, a Matlab Simulink simulation was carried out. The results of the simulation using Matlab Simulink show that the use of a zig-zag transformer can reduce the total current harmonics (THDi) of each phase R, S, T by 26.29%, 25.86%, 26.17%. to be 1.56%, 1.55%, 1.56%. As well as reducing the current in the neutral conductor by 47.8%.