The PRASA Chair continuously makes use of the 'virtual laboratory' within the University of Stellenbosch to perform laboratory research projects for PRASA. Some projects, which required specialists from the Electrical and Electronic Engineering department and their laboratories, will now be discussed.
The PRASA Chair was requested to investigate factors influencing corona and air gap breakdown on the overhead conductor, and the purpose of the project was to determine the conditions under which negative and/or positive corona will be visible, and the influence thereof on the breakdown of the air gap. With world class facilities to its disposal, the High Voltage laboratory was used to perform tests on a scale model, taking into account the geometry of the contact wire, geometry of the objects on the roof of the train and the parameters of the air gap (i.e. humidity, temperature, foreign objects, and altitude).
During experiments, the environmental conditions of the air gap were changed, simulating moving warm air, air with a high humidity, air with diesel exhaust fumes and water condensation on the contact wire, and the worst conditions were identified. All the conditions were benchmarked with ambient dry air at sea level, where the tests were conducted.
Other tests done in the laboratories include the testing of a train antenna and the testing of surge absorber roof capacitors.
Besides laboratory tests, continued research is done on ad-hoc topics, including alternative battery technology for the starting of diesel locomotives, an alternative concept LED light system for inside passenger coaches, and energy efficient studies using optimising roof space.