Analysis of a PWM Converter with Less Current Ripple, Wide Voltage Operation and Zero-Voltage Switching

This paper studies and implements a power converter to have less current ripple output and wide voltage input operation. A three-leg converter with different primary turns is presented on its high-voltage side to extend the input voltage range. The current doubler rectification circuit is adopted on the output side to have low current ripple capability. From the switching states of the three-leg converter, the presented circuit has two equivalent sub-circuits under different input voltage ranges (Vin = 120–270 V or 270–600 V). The general phase-shift pulse-width modulation is employed to control the presented converter so that power devices can be turned on at zero voltage in order to reduce switching loss. Compared to two-stage circuit topologies with a wide voltage input operation, the presented converter has the benefits of simple circuit structure, easy control algorithm using a general integrated circuit or digital controller, and less components. The performance of the presented circuit is confirmed and validated by an 800 W laboratory prototype.