Document Type



This item is available under a Creative Commons License for non-commercial use only


Electrical and electronic engineering

Publication Details

Journal of Electric Power Systems Research, Vol. 77, no. 7, 2007, pp.821-830 Available from


Majority of the dispersed generations from renewable energy sources are connected to the grid through power electronic interface, which introduce additional harmonics in the distribution systems. Research is being carried out to integrate active filtering with specific interface such that a common power quality (PQ) platform could be achieved. For generalized solution, a unified power quality conditioner (UPQC) could be the most comprehensive PQ protecting device for sensitive non-linear loads, which require quality input supply. Also, load current harmonic isolation needs to be ensured for maintaining the quality of the supply current. The present paper describes two control scheme models for UPQC, for enhancing PQ of sensitive non-linear loads. Based on two different kinds of voltage compensation strategy, two control schemes have been designed, which are termed as UPQC-Q and UPQC-P. A comparative loading analysis has developed useful insight in finding the typical application of the two different control schemes. The effectiveness of the two control schemes is verified through extensive simulation using the software SABER. As the power circuit configuration of UPQC remains same for both the model, with modification of control scheme only, the utility of UPQC can be optimized depending upon the application requirement.