This paper deals with the evaluation on loading effect of series resonance circuit at the point of common coupling (PCC) of an asynchronous generator. Effect of frequency variations on series resonance circuit and its effect on input side of the uncontrolled rectifier have been investigated experimentally. The result shows power factor has been improved even though load current is lagging behind the source voltage. Power factor angle is reduced when the inverter output frequency is below the resonance frequency. This reduction in power factor angle reflects the effect of leading Var injection into the source. © 2009 IEEE.