摘要
有源功率因数校正(PFC)通常采用 Boost 变换器,在低压 90V 输入时,其输出电压调节在 380V,此时变换器效率最低。该文提出一种变输出电压的控制方式,其输出电压随着输入电压的变化而变化。这种方法可以缩短开关管的导通时间,减小流经开关管的电流有效值,从而降低其导通损耗,提高变换器的效率。分析了 Boost PFC 变换器的损耗分布和控制方法。最后在一台 1200W 的原理样机上进行实验验证,还对比快恢复二极管和 SiC 二极管的关断特性,给出实验结果。
Boost converter is widely used as active power factor correction (PFC) pre-regulator. Its input voltage range is universal (90-265V), and its output voltage is regulated at about 380V. At low line input (90V) the input current is high, so the conduction loss of power switch MOSFET is large and the efficiency of whole converter is very low. This paper proposes a new control method that the output voltage varies with the input voltage change. Under this control the MOSFET’s on-time is shortened, and the switch’s rms current decreases, which reduces the conduction loss and increases the Boost converter efficiency. The distribution of power loss is analyzed by computing software (mathcad2000) and the realization of this special control method is given. A 1200W Boost power factor corrector with average current control is built up. The performance of a 600V, 12A silicon carbide (SiC) Schottky diode is experimentally evaluated. Measurements of overall efficiency and reverse recovery behavior are compared between SiC diode and fast recovery diode.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2004年第10期153-156,共4页
Proceedings of the CSEE
