PMU based islanding detection to improve system operation

A prompt and accurate bulk system islanding detection capability is essential for real-time operation to maintain system reliability. This paper introduces and proposes two islanding detection methods, “Frequency Standard Deviation” and “Relative Phase Angle Change Rate” based on PMU measurement. The detailed analysis and explanation of the approaches to the design of islanding scheme is provided in the paper. Historical synchrophasor data is applied to examine the effectiveness on proposed methods. Off-line simulation results show that the methods can quickly detect system islanding and provide the immunity to other system disturbances. In addition the methods do not rely on the model of the system configuration nor the availability or accuracy of SCADA measurement that greatly impacts on the islanding detection in the EMS. The proposed methods are able to contribute to real time operation so as to improve the system reliability.