商用型功率因數修正電路之小信號穩定度分析與量測

Abstract

本論文之主要目的在於分析與量測功率因數修正電路 (Power Factor Correction Circuit, 簡稱PFC) 之小信號模型，藉由設計系統之回授補償器，進而分析系統穩定度。

首先介紹數種功率因數修正電路之架構與常用之控制策略，接著將詳述功率因數修正電路之動作原理，並推導出包含電流迴路與電壓迴路的平均電流模式之小信號模型，其次將推導的電流迴路與電壓迴路之小信號轉移函數，用以設計系統回授補償器，並配合數學工具軟體MATHCAD與MATLAB計算與驗證其可行性。

實作採用德州儀器公司生產之商用型功率因數修正控制晶體UCC3817實現控制迴路補償器，實際經由頻率響應分析儀量測所得之結果，並與計算之結果比較後皆相符合。最後本文歸納出一套實際量測電流迴路與電壓迴路之步驟與考量，提供給工業界作為設計時的重要參考，並作一結論。

The theme of this thesis is focused on the measurement and analysis in the small signal model of a power factor correction circuit (PFC). By the design of a system feedback compensator, the analysis of system stability is achieved.

In this thesis, several PFC models and control methods are introduced, and the operating theory of PFC is illustrated in detail. In further, the small signal models in average current mode of both current and voltage loops are derived so that the transfer functions can be applied to the design of the system feedback compensator. In order to validate the feasibility, the MATHCAD and MATLAB programs are applied to test the accuracy.

By utilizing TI commercial PFC control IC “UCC3817”, the control loop compensator is implemented and completed. The measurement results of frequency response analyzer are in accord with the mathematical computation. In the end, the practical techniques and approaches to measure both current and voltage loops, which can be an important reference for the industry, are advanced and come to a conclusion.