Harmonic sources and filtering approaches-series/parallel, active/passive, and their combined power filters

This paper presents 22 configurations of power filters for the harmonic compensation of nonlinear loads. Some of these configurations are novel and result from the newly discovered characteristics of nonlinear loads and circuitry duality, while the others are well known and used in practice. Nonlinear loads are characterized into two types of harmonic sources-current-source nonlinear loads and voltage-source nonlinear loads. These two types of harmonic sources have completely distinctive, dual properties and characteristics. Based on their properties and characteristics, the current-source nonlinear loads and voltage-source nonlinear loads have their own suitable filter configurations, respectively. This paper reveals 22 basic configurations: active and passive, series and parallel, and hybrid and combined power filters. Among them are some novel filter configurations, and their advantages are discussed and demonstrated by analysis, simulation, and experiment. In addition, a comprehensive comparison of all configurations is made in terms of required ratings, costs, performance and controls.