Research on oscillation center identification and its application in distance relay protection

摘要

The identification of oscillation center is of importance for improving distance protection to avoid the malfunction of distance protection in power oscillation. After analyses the relationship between oscillation center and the current and the voltage in protection installation site, this paper provides a novel method to locate the oscillation center based on the local electrical information. This method uses local voltage, current and the impendence of transmission line which is to be protected to identify whether the oscillation center is in the protection zone or not. This method is not affected by the voltage amplitude and the impendence angle. The effectiveness of this method has been demonstrated by PSCAD simulation. This method can be applied to the existing blocking logic to improve the functioning of distance protection in power oscillation.