Current converter with transformer primary and transistor in series - has air gap in core to limit magnetisation current to fraction of collector current

摘要

The circuit consists of a series circuit comprising the primary windings of a transformer and the collector emitter junction of a switching transistor. The series circuit is fed from a direct voltage source. The secondary windings of the transformer is used to supply the load. The core of the transformer is made with an air gap. The dimensions of the air gapn are made such that the magnetisation current of the transformer will amount to approximately one tenth of the maximum collector current. The circuit avoids extending the switching off time of the switching transistor.