UPQC — The best solution to improve power quality in low voltage weak distribution networks

Abstract

The answer to global problems challenging energy sector was to use more efficiently local alternative (non-conventional fossil fuel or renewable) energy resources. In power systems, the use of renewable energy (RE) based distributed generation (DG) has increased considerably all over the world; the presence of DG units at distribution voltage level determines the transition from traditional passive to new active distribution networks. Concurrently, the modern distribution networks supply a large variety of non-linear loads based on power electronics contributing to increased current and voltage harmonics issues; dynamic loads and unbalance in power systems cause other power quality problems. The Romanian power system faces some challenges in order to ensure the reliability and quality of the power supply, especially in low voltage (LV) rural and sub-urban grids; thus, the power quality issues must be appropriately identified in every network while their assessment is the key element in the design of measures aiming to diminish all existing disturbances. A research project aims to identify the power quality issues and the impact of DG or other non-linear loads on LV distribution networks in Romania; the final goal is to develop an equipment able to remove or, at least, to mitigate all electromagnetic disturbances considering the characteristics and sensitivity of end use equipment within customer facilities.