The book starts from the existed problems in fault analysis of the lumped-parameter circuit model. It firstly introduces the basic electromagnetic phenomenon, uniform transmission line guided electromagnetic waves, multi-conductor system guided electromagnetic waves, fault generated travelling waves; then it introduces series of the traveling waves based protections, which includes principle, technology and application in practical power grid; it also discusses the travelling waves based fault location and the travelling waves based fault feeder selector in China. It systemically reveals the...