High-speed transmission line protection using principal component analysis, a deterministic algorithm

A novel methodology to provide effective fault protection featuring high speed and excellent selectivity is presented. Principal component analysis made up of a set of travelling wave current signals, measured at one end of the transmission line, exhibits a well-defined pattern for faults of the same type. This work discloses that the fault current signal projected on the principal component coordinates can define the position, the insertion angle and the fault type (single-phase to ground, isolated two-phase, two-phase to ground and three-phase faults) on transmission lines. In this manner, it is possible to effectively categorise internal faults as well as distinguish when the fault is outside the line. Time windows less than a quarter of cycle of the power frequency are used to measure the current signals, thus the methodology is applicable for high-speed protection systems.