Transient Wavelet Energy-Based Protection Scheme for Inverter-Dominated Microgrid

When faults occur in the microgrids, high frequency transients will be superimposed on system currents and voltages. The magnitude of those attenuate as it encounters discontinuity points network such busbars, or any other impedance points. This phenomenon can also quantified by wavelet energy, which provides a useful tool to detect locate faulted feeder microgrid. In this paper, novel protection scheme based transient energy current extracted Maximal Overlap Discrete Wavelet Transform (MODWT) algorithm is developed microgrids. Compared with existing schemes, proposed has advantage being largely immune changes fault level, types positions, microgrid operating status control strategies deployed inverters, while presenting much lower requirement sampling (10 kHz) compared travelling wave-based methods. Unlike conventional differential protection, does not require synchronized measurement bandwidth communication channels, thus, considered an economical promising solution for