AC filter based on self-tuned controllable reactor

Compared with the active filters, passive filters are widely used for their cheaper costs, simpler structures and more reliable performance. But conventional passive filters which consist of parameter-fixed capacitors and reactors can not remain good filtering performance in case the system frequency shifts or component parameters change. This thesis compares the advantages and disadvantages of two feasible control methods based on the research of a sort of passive filter using controllable reactor instead of parameter-fixed reactor. And then, an improved method is proposed and a self-optimizing algorithm is presented. Good performances of the filter are verified by experiments both in laboratory and at the locale of a use. The results prove the practical value of this control method.