AN ANALYSIS OF ROTOR DOUBLE POINT GROUND FAULTS
Shi Shiwen · Electric Machines & Power Systems · 1998
This paper analyses the second harmonic component which appears in stator emf during rotor double point ground faults or interturn faults. The second harmonic component can be used to realize rotor double point ground protection for large generators. Starting from basic physical concepts, the paper discusses the rotor winding mmf and gap flux density distribution during normal and fault conditions as well as corresponding stator harmonic emf. A method of “calculate flux density curve” is proposed, so that analysis process is simplified and more convenient.