| Abstract |
After a review of the production of harmonics in circuits fed or controlled by diodes and thyristors, a series of tests is illustrated that was carried out on the FERROVIE NORD MILANO' s network, in view of the introduction into service of a set of new electric motor-coaches fitted with chopper equipment, in order to find out whether or not the possibility of interference between said harmonics and the signalling current did in fact exist. A first series of tests was carried out (1982), and a second series (1984), using two chopper equipped electric motor-coaches. The test results were very comforting, for it was found that both the substation and the converters on board the motor-coaches do produce some harmonics in the track, that could interfere with the signaling currents, but said harmonics are not able to activate the safety equipment. |
