Thyristor controlled reactor methods to increase the capacity of single wire earth return systems

Single wire earth return systems are a widely applied low cost power distribution method used in many rural areas. In Central Queensland a single SWER system supplying approximately 100kW may extend more than 300km. These systems often use shunt reactors to compensate the effects of line to ground capacitance. Recent patterns of load growth are forcing the upgrading of these systems. As voltage regulation is the determining factor, the replacement of fixed shunt reactors with controllable reactors provides an opportunity to significantly increase the system capacity. A study of the North Jericho SWER system shows a capacity increase of approximately 85% can be achieved.