Analysis Of Power System Reliability Based On Hidden Failures Of Protective Relayings

This paper analyzes three existing hidden failure models, proposes a new hidden failure model considering repairable hidden failure, aging hidden failure and the hidden failure caused by adverse environment. Using the DC power flow algorithm to assess the risk of power system cascading failure, to find out the key-lines, on this basis the preventive measures to reduce the risk of power system cascading failure is put forward. The results of applying the proposed method to TH-9Bus and IEEE-14Bus test systems illustrate the method improving the reliability of the relay,?improving the line capacity can reduce the risk.