Protection of microgrid

The presentation analyses the existing protection of the microgrid, and, in order to meet the requirements of microgrid protection, a novel protection is presented. The protection, which is based on local information without the need for communication, uses current traveling waves to identify a faulty feeder, and the bus bar voltages to determine an event caused by the fault or switch operation. In the protection scheme, current traveling waves are measured by current transducers in N-line and phase lines, and wavelet multi-resolution analysis is used to decompose the traveling wave signals. The initial traveling waves are compared in magnitude and polarity with each other to determine the faulty feeder. The protection is independent of the microgrid operation connected with the main power grid or in an island.