A Shunt Active Filter for Extenuation of Harmonics by Compact Fluorescent Lamp Drives

Compact fluorescent lamp (CFL) drives exhibit a highly non-liner characteristic. The current drawn by CFL lamps is non-sinusoidal and rich in harmonics. Effect of individual CFL units installed alongside larger linear loads is trivial. However, a large number of CFL lamps installed with smaller linear loads cause measurable harmonic distortion in current. Active power filters (APF) are a popular method of reducing harmonic distortion. APFs are much used in industry for extenuation of harmonics created by six pulse rectifiers and AC drives. Estimating the harmonic component of load current is essential to the performance of active power filters. While harmonic current estimation methods are developed for larger industrial harmonic loads, their performace with smaller loads as CFLs varies. This work explores the effectiveness of the instantaneous reactive power theory (IRPT) and stationary frame method in estimating harmonic component current drawn by CFLs. An active power filter is then modeled in Simulink using stationary frame method and its performance evaluated with six pulse rectifier load as well as three phase unbalanced CFL load.