An 18 kVa transistor chopper amplifier for use on BR magnetically, levitated test vehicle (IM-EDYN-023)

1. INTRODUCTION Attractive magnetic levitation requires that the suspension magnet current is accurately controlled to maintain a magnet/rail air gap within the constraints of the suspension control system. Light-weight and compact design is offered by using a transistor chopper amplifier as an interface between control circuitry and lift magnets.