Abstract:
Electrode line open circuit protection for blocked pole will mal-operate due to the induced voltage caused by the healthy pole line after single pole fault,and then block the healthy pole.To avoid thus situation,an improvement scheme is proposed from both control and protection aspects.In the control aspect,a new pole isolation method is adopted,the line switch is switched off as soon as possible to avoid induced voltage.In the protection aspect,a current criterion is added and consequences of protection operation is also suggested.The feasibility and effectiveness of the scheme is verified by real-time digital simulator(RTDS) based simulation tests.