Steady state characteristics of a hybrid type series active power filter used in single-phase circuit

As a new filtering device used in single-phase circuit, hybrid type series active power filter is a combined system of shunt passive filter and series active filter. This paper makes descriptions on the steady state characteristics of this device, based on its control method and operation principles. The steady state characteristic curves are obtained. The relationship between the steady state performance and control gain is well discussed. And its suppressing action upon the possible resonance in the circuit is analyzed in detail. Computer simulation and experimental results showed that, single-phase hybrid type series active power filter has good steady state compensation characteristics and can dramatically suppress parallel resonance and series resonance between source impedance and shunt passive filter.