Ultra-High-Speed Travelling Wave Protection of Transmission Line Using Polarity Comparison Principle Based on Empirical Mode Decomposition

Table 1

Analysis of travelling wave polarity comparison protection.

Fault location	Superimposed voltage polarity	M side		N side		Schematic of fault superimposed state circuit
		Voltage	Current	Voltage	Current
Internal fault	+; −	+; −	−; +	+; −	−; +
External fault	+; −	+; −	−; +	+; −	+; −
External fault	+; −	+; −	+; −	+; −	−; +