Research On Some Problems In Distance Relaying

This paper presents a method of distinguishing fault from power swing as well as selecting of fault phases based on wavelet transform. A new criterion is presented. The method presented in the paper has many advantages such as simple algorithm, accurate discrimination results and strong immunity to disturbance. A study of comparison between FT and Kalman filter under some familiar conditions is presented, and some useful conclusions are acquired.The methods of calculating correctly of original phase angle of fundamental component using FT have also been presented in this paper. Causes are analyzed, and the improvement methods are presented. Dong Jie (Power system and its Automation)Directed by Professor Zhang Ju...