Computation of electromagnetic fields in the vicinity of a railway catenary

An understanding of the influence of railway power systems on the local electromagnetic environment is of importance to ensure that such installations will satisfy the protection requirements of the EMC regulations. Although these characteristics must ultimately be demonstrated experimentally, the ability to make predictions in advance could help to establish emissions specifications for on-board systems. Here, the author describes how, in order to investigate the potential for such analysis, measurements are being undertaken by GEC ALSTHOM Metro Cammell, in collaboration with GEC ALSTHOM Traction. These results are compared with theoretical values computed using SLIM, an electromagnetic field modelling package developed by GEC ALSTHOM Engineering Research Centre