Mains converter for a multi-system, multiple-unit train

摘要

It is intended to specify a circuit arrangement for a mains converter of a DC voltage intermediate circuit converter on a multiple-unit train, which mains converter can optionally be connected to an AC voltage network or to one of two DC voltage networks of different voltage amplitude, by means of which circuit arrangement as few semiconductor switches (especially GTO thyristors) as possible are used in an optimum manner for different types of voltage. To this end, two bridge circuits (which operate as four-quadrant controllers during AC voltage operation and consist of in each case four semiconductor switches (T1 to T4 and T11 to T14) which can be switched off) are connected in series with freewheeling diodes (D1 to D4 and D11 to D14), which are in each case connected in reverse parallel, with their AC voltage connections being isolated, are connected to the higher mains DC voltage and are operated as two-quadrant controllers. In the case when the supply is provided from the lower mains DC voltage, the arrangement can be switched over to a step-up controller.