A multi-resolution Morphology Gradient based non-communication protection scheme for transmission lines

A new transient multi-resolution morphology gradient based protection scheme to trip immediately without communication channel is proposed in this paper. Mathematical morphology gradient is then used to decompose the transient signal to extract high-frequency transient component. A fault can be identified as internal or external one according to the spectrum energies in foregoing two selected layers results of multi-resolution morphology gradient. The PSCAD simulation results show that the method proposed can accurately and reliably carry out the fault selection in every fault case with proper stray capacitance and sampling frequency.