Indirect current control of series hybrid filter: an experimental study

Abstract

Series active filtering has been identified as an appropriate solution for voltage fed type harmonic producing loads. Moreover, the amicable configuration demands employment of a set of shunt connected passive filters so as to suitably compensate harmonics and retain the characteristics of multiple diverse connected loads. This paper presents experimental study of series hybrid filter system (SHF) to eliminate harmonics generated by nonlinear load and meeting the variable limited reactive power requirements corresponding to available rating of the voltage source inverter (VSI) employed as active filter (AF). The SHF is desired to operate in a way not to compensate negative sequence component, therefore, the indirect current control based on synchronous reference frame decomposition of current has been employed and discussed in details. The implementation of the control has been done on digital signal processor (DSP) for developed prototype of AF in SHF. The passive filters set has been developed keeping in view of its operation with SHF. Operation of SHF under dynamic change of load has also been investigated through simulations under MATLAB and through experimentation.