Protection performance and analysis for faults in generating units and transformers

Understanding the criticality of generator, excitation system and transformer for the active existence of power plant it is utmost necessary to maintain them under protective environment.

The need to analyze the possible causes and required protection is diagnosed during the design stage itself.

The generator main circuit connecting to generator transformer, UAT and Excitation Transformers is through Isolated Phase Bus-ducts. Possibility of occurrence of ground or phase faults would be seldom.

The priority of protection relay scheme and setting is to safely isolate the fault as fast as possible and at the same time maintain stability in grid and generator at the power plant.

Protection relay shall be coordinated with generator excitation control system such as Automatic Voltage Regulator (AVR), Thyristors etc.

Case study has been prepared based on the past experience of project feedbacks.