Operation Modes of a 50-60 Hz Superconducting Converter

The operation at mains frequency of 50–60 Hz allows for a simplification of the superconducting converter construction at a reasonable efficiency of 96–98 % (while pumping up and down a superconducting magnet). Besides, new possibilities appear in the interaction between the mains and the magnet via the converter. The operation modes of a new superconducting converter connected to the mains and to the superconducting magnet are considered in the paper. The converter ‘cold’ part consists of the fast response thermally controlled switches, a non saturated iron core superconducting transformer and the current sensors in the branches. The PC-based control unit includes “direct” and “shunting” switches and allows to realise various algorithms of the converter control. It is shown that both AC to DC, and DC to AC conversion with the magnet-mains energy exchange in both directions via the converter can be realised. In the paper such an operation is described theoretically and verified by the physical and numerical experiments