Study on a new shunt hybrid active filter

In order to realize the functions of harmonic compensation and power factor continuous adjustment for nonlinear loads,a transformerless shunt hybrid active filter is proposed.In this paper,the main operational principle of the active filter is discussed firstly.To make a compromise in cost and filtering performance,we choose a passive filter tuned at seventh harmonic frequency,which makes a not good filtering performance in the mose domiant fifth frequency,a feedback and a fifth harmonic frequency feedforward control scheme is proposed.In order to compensate the system ractive power further,a certain improvement is made in the original feeback control links.The simulation results verify the efficiency of the shunt hybrid active filter.