A new form of magnetically coupled DC/DC converter is proposed for medium power applications (250 W to 2 kW), requiring a high-voltage gain, short inductive charging time and galvanic isolation. The proposed converter can be realised using a unique Y-source impedance network and a two-switch push-pull circuit with voltage-doubling rectification. The converter's voltage gain is presently not matched by any other converter operating at the same switch duty ratio. The converter also has more degrees of freedom in design for setting the desired gain than other converters, and hence can better meet the demands of many applications. The operating principles of the converter have been analysed mathematically, and are verified by both simulation and experiment.