| Summary: | 博士 === 國立臺灣科技大學 === 電子工程系 === 106 === This dissertation will based on mathematical to analysis Totem-Pole bridgeless ACDC PFC converter in detail. Which include operation principle, power component design, feedback circuit design, control loop analysis, digital control loop analysis, digital compensator design and harmonic suppression strategies. Then verify with simulation and experimental results. On the other hands, due to lack of rectifier. The common mode EMI is higher than conventional Boost PFC converter. In order to improve efficiency. The small RDS(on) MOSFET usually use as slow leg’s switch. The most of these are Super Junction structure. Because of its non-linear Coss characteristic. The common mode current spike will occur at every AC zero-crossing point. By derived this current spike’s equation from EMI model in mathematical theory. And then compare with adopt zero-crossing soft-start solution. Find the relationship in input current THD and EMI result. Then proposed a design procedure. In the CM-EMI experimental result, after use ZCSS. The frequency at 1.7 MHz, 2.6 MHz, 5.4 MHz, 14 MHz. These noise level are reduced over 15 dB. Therefore, the ZCSS can suppress CM-EMI significantly.
|
|---|
