Characteristics of fast real time symmetrical coordinate transformation used for fault ride through

Abstract

In the utility system, the most popular fault is 1 line-to-ground fault. It causes the imbalance voltages and currents in 3-phase power system. This paper presents the novel unbalanced fault detection by using the very fast real time symmetrical coordinate transform from the memorized 3-phase voltage data before 1 sampling time. This paper presents some characteristics of the very fast real time symmetrical coordinate transform (VFRT-SCT) from the memorized 3-phase voltage data. The effects of the harmonic components are mainly described here. As shown in the analytical results, certain amount of error occurs when the harmonic component is included in the utility voltage.