Analysis of a device for converting a unipolar input voltage into two symmetric bidirectional output voltages with a magnetically coupled coil

摘要

A new principle of a DC-DC converter with a magnetic coupled coil is analyzed. The speciality of this converter is that it transforms a unipolar input voltage into two symmetrical bidirectional DC voltages with only one power switch. The value of the output voltage can be varied by the duty cycle of the switch. The generation of two symmetrical voltages, one positive and one negative related to ground, makes it possible to invert a DC voltage to a single phase AC network with only three switches. For the operation of a class - D amplifier, for multi quadrant operation of DC motors or actuactors a symmetrical bidirectional supply voltage can also be very useful. After basic analysis in continuous inductor current mode, dimensioning of the converter components, a state space model and linearized transfer functions for the control of the converter are derived.