Properties, simulation and experimental investigation of the series-parallel active power filters

In this paper introduced calculate method of active power filters passive components, simulation and experimental researches results of the series-parallel active power filter. Authors especially occupy oneself with analysis power flow between both active filters in UPQC system and nonlinear load. This problem is according to authors very important, because it makes possible to find optimum configuration of the hybrid UPFC and power of the additional sources elements.