Power circuit for transferring energy by alternately switching winding circuits of a transformer at high speed

摘要

In a power supply unit, AC energy is converted to DC energy and stored into a first capacitor to which a first winding of a transformer is connected. An anti-parallel circuit of a first transistor and a diode is connected between the first capacitor and the first winding. An anti-parallel circuit of a second transistor and a diode is connected between a second winding of the transformer and a second, battery-charging capacitor. A current is induced in a third winding of the transformer for charging a third capacitor when a current is produced in the first winding in a particular direction or when energy stored in the second winding is released into the third winding. The first and second transistors are alternately switched on so that energy is transferred from the first capacitor to the second and third capacitors when the AC energy is normal and energy is transferred from the battery to the third capacitor when the AC energy fails.