Application of LC filter in harmonics reduction

Abstract

In recent years, harmonics are considered as one of the most essential problems in electrical power systems. Even though, this new highly efficient electronic technology provides improved product quality with increased productivity by the use of smaller and lighter electrical components but they are the sources of harmonics. Recent surveys on the three-phase four-wire electric power distribution systems with computer and nonlinear loads show excessive currents in the neutral conductor. The neutral currents are basically zero-sequence current harmonics, which is mostly, consists of triplen current harmonics. As a result, the perfect sinusoidal voltage and current waveform are very much distorted. To solve this problem, a simple and practical approach to reduce harmonics current in 3-phase 4-wire power distribution system is proposed. The using of LC filter in three-phase four-wire system reduces the harmonic problem in the system. This LC filter is depending on value of capacitor and inductor. It is not only reducing zero-sequence harmonics but also reduce other harmonics in the system. Besides that, this application also can improve power factor and reduced the THD system to the standard IEEE-std 519. The practical excellency and validity of reducing are demonstrated experimentally.