Title :
A new scheme for power transformer protection
Author :
Yang, J.C. ; Yin, X.G. ; Chen, D.S. ; Zhang, Z. ; Wang, Z.H.
Author_Institution :
Dept. of Electr. Eng., Huazhong Univ. of Sci. & Technol., Wuhan, China
Abstract :
In this paper, a new transformer protection scheme is proposed which is based on the combination of virtual 3rd harmonic restrained and sampled value differential principles. The differential protection restrained by virtual 3rd harmonic can identify asymmetric and symmetric inrush currents with semi-cycle data window and accelerate the protection tripping speed. The sampled value differential protection can overcome some disadvantages of harmonic restraining with a long delay in the case of high content of harmonic components during internal faults. The combination scheme takes advantages of these two methods and improves the protection performance effectively. Test results in Electrical Power Dynamic Laboratory (EPDL) illustrate the proposed scheme. Now the protection system has been put into trial operation in GeZouBa Hydroelectric Power Plant.
Keywords :
fault currents; power engineering computing; power system protection; power transformer protection; Electrical Power Dynamic Laboratory; GeZouBa Hydroelectric Power Plant; differential protection; inrush currents; internal faults; power transformer protection; protection tripping speed; semicycle data window; virtual 3rd harmonic differential principles; Circuit faults; Delay; Fault currents; Laboratories; Power system dynamics; Power system harmonics; Power system protection; Power transformers; Surge protection; Testing;
Conference_Titel :
Transmission and Distribution Conference and Exposition, 2003 IEEE PES
Print_ISBN :
0-7803-8110-6
DOI :
10.1109/TDC.2003.1335247
