A review of recent investigations on voltage unbalance management: Further contributions to improvement of IEC/TR 61000-3-13:2008

Voltage unbalance (VU) management in power systems essentially involves two major aspects: VU emission allocation at the pre-connection stage and compliance assessment at the post-connection stage of installations. This is a summary and a review paper on the recent investigations completed in relation to VU emission assessment techniques which provide further contributions to the improvement of IEC Technical Report IEC/TR61000-3-13:2008. Generalised approaches developed for the classification of different sources of unbalance at the point of evaluation (covering both radial and interconnected networks) and the evaluation of their individual contributions giving emphasis to the discrimination between customer and network responsibility on VU emission are summarised. Some of the key aspects used in the IEC VU emission allocation methodology which were reviewed using rigorous outcomes of the proposed VU emission assessment techniques are presented in the paper.