High-Power-Factor Single-Stage LCC Resonant Inverter for Liquid Crystal Display Backlight

The aim of this paper is to propose a high-power-factor (HPF) single-stage inductor-capacitor-capacitor (LCC) resonant inverter for liquid crystal display (LCD) backlight. A half-bridge LCC resonant inverter shares switches with a power-factor-correction circuit to form single stage. The proposed single-stage LCC resonant inverter can achieve almost unity power factor and ripple-free input current by using a coupled inductor, and can also realize zero-voltage-switching by operating the switches above the resonant frequency. Thus, the proposed single-stage inverter not only provides HPF to the utility line, but also achieves circuit simplicity, low cost, and high reliability. Experimental results on a 32-in LCD backlight are obtained to show the performance of the proposed inverter.