Time Domain Voltage Unbalance Index Based on Second Order Voltage Tensor Theory

This paper proposes an alternative index capable of evaluate voltage unbalance in time domain. The proposed index it's called voltage unbalance level (VUL) and makes use of the second order voltage tensor theory in order to assess voltage unbalance. A correlation between VUL and the voltage unbalance factor (VUF) is exposed for unbalances on magnitude and phase angle. The mathematical foundations of this theory and a behavior analysis of both indexes are also presented in this study.