Regenerative braking equipment on cape western system of the South African railways

The purpose of regeneration is reviewed briefly and the various methods of absorbing energy in excess of traction requirements are discussed. The principal reasons for using power dissipating resistor equipment are presented. A brief description of the Cape Western traction electrification follows which includes details of the locomotives used and the method of locomotive control during regenerative braking. The operating requirements of the regenerative braking equipment are stated and details of the various circuits are discussed. Descriptions of the ignitrons and the main resistors follow and a general survey of the equipment is given. An account of the tests carried out on the electronic and power equipment is given and typical results of tests involving locomotives in regenerative combination are reported. The operation of the equipment in service is stated briefly and proposed modifications in design to the present equipment are discussed. A summary of desirable and undesirable features in regenerative braking equipments concludes the paper.