Predictive algorithm to measure criterion values of digital power system protections

摘要

The article presents a method of synthesizing some simple digital predictive filters for the quick identification of short-circuits in the power systems; it also describes their basic properties. The predictive filters perform an approximation of the current and voltage characteristics (in appropriately narrowed time intervals) by applying the sections of aperiodic functions (low degree polynomials). The combination of digital predictive filters using first- and second-degree polynomial approximation is analysed. Particular attention is paid to the optimization of dynamic properties. The objective of predictive filters performing the digital algorithms to measure criterion values is to decrease the identification time in case of an interference, and to reduce the negative influence of the transient state upon the decision being made.