New resonant LCL boost converter

This study presents a new soft-switching resonant step-up converter. An auxiliary high-frequency resonant LC tank along with a switch constitute the auxiliary network added to the classic pulse width modulation (PWM) boost converter. Size of the main inductor of boost converter is also reduced, so that in conjunction with the auxiliary LC tank forms an LCL resonant network. This network provides zero-current switching (ZCS) conditions for both switches independent from the load-current and operating voltages. The converter can operate at ZCS in discontinuous conduction mode, continuous conduction mode (CCM) and deep-CCM depending on the switching frequency; and, at deep-CCM, the current stresses are minimised. Experimental results from a 100 W/100 kHz laboratory prototype verify the integrity of the presented theoretical analysis.