Case Study of a Cascading Fault with Tripping of All Main Transformers in a 220kV Substation

摘要

T250 paper describes and analyzes a cascading fault in an actual power grid. During the temporal evolution of the complicated contingency, all main transformers in a 220kV substation were tripped by different digital relays. This paper uses fault wave recording, theoretical analysis and simulation to discuss the operation behavior and reasons of corresponding protection devices. Theoretical calculation and simulation results show that the proposed analysis is effective and correct.