A Novel Single-Phase Single Stage Topology for Chargers

The novel single-phase single stage topology for charger is proposed in this paper. This topology, where the freewheeling inductance is placed at the AC side, uses a single switching device to control the output voltage and current. The main principle of the novel topology is described, and the operating performance is analyzed by simulation. The control strategy of the novel charger is discussed. Comparing with the traditional charging circuit, the introduced circuit does not add any devices. When the input current is working at DCM (discontinuous conduction mode), the novel circuit has several advantages by changing the direction of the current of the freewheeling inductance. Both the output voltage of the rectifier bridge and the voltage and current stresses applied on the switching devices are lessened, and the input current harmonics is also cut down. The reduced stresses can prolong the service life of the charger