Summary: | 碩士 === 國立成功大學 === 電機工程學系碩博士班 === 96 === This thesis focuses on the analysis and design of low frequency active power factor correction circuits (LFAPFC). It has been recently reported that LFAPFC has attractive features such as low EMI and low switching loss when compared with high frequency active power factor correction circuits (HFAPFC). Moreover, its performance is better than that of passive power factor correction circuits (PPFC). However, studies on the major control parameters of LFAPFC and their corresponding performance are limited. This thesis proposes a design method that is based on a trapezoid current waveform. Using the proposed method, the output performance such as total harmonics distortion (THD) and power factor (PF) of LFAPFC can be approximately estimated when the major control parameters, i.e., the conduction timing and conduction period of the power switch are determined. In addition, the relationship between the value of the inductor and the conduction parameters of the power switch is derived and investigated. Designers can determine suitable values of conduction parameters and inductors for specific applications. Theoretical analysis, computer simulation, and experimental results demonstrate the effectiveness of the proposed method. Using the proposed method, designers can save considerable time choosing the value of control parameters and inductors.
|