Novel Approach for Synchronous Generator Protection Using New Differential Component

A new stator fault detection and classification scheme for synchronous generators (SGs), based on an amplified discrete Teager-kaiser energy operator (ADTKEO) of a new differential component (DCSI), is proposed. Detection of an internal fault is based on the fulfillment of the ADTKEO (?) with respect to the pre-determined threshold along with the checking of second-harmonic content in the current transformer (CT) secondary current. Afterward, the classification of internal faults is performed based on '?'. The performance of the proposed scheme is tested on various fault cases obtained from a simulation network developed in a real-time digital simulator and the developed laboratory prototype of the SG. The results indicate that the proposed scheme not only provides 100% winding coverage against phase-to-ground faults but is also capable of detecting other phase faults within a quarter cycle for low-resistance grounded SGs. At the same time, it stays extremely stable for external faults, even considering errors in CT along with its saturation (without compromising speed/sensitivity). The proposed scheme is independent of the sampling frequency, loading condition, decaying dc component present in the acquired signals, and rating of the SG.

Automated summary

A new stator fault detection and classification scheme for synchronous generators (SGs) is proposed, based on an amplified discrete Teager-kaiser energy operator (ADTKEO) of a new differential component (DCSI). The scheme achieves 100% winding coverage against phase-to-ground faults and can detect other phase faults within a quarter cycle for low-resistance grounded SGs. It is also stable for external faults, even with errors in CT and its saturation.