本論文旨在半橋式功率因數修正器輸出電壓不平衡的原因與補償之策略,首先以平均電路模型分析雙開關半橋式功率因數修正器輸出電壓不平衡之原因,並經由加入一個直流補償電流予以消除輸出電壓不平衡,此直流補償電流大小與輸出兩負載差值相當。不平衡的輸出負載,將影響到輸出電壓不平衡及輸入功率因數,因此加入一低通濾波器來消除電壓差之交流成分,以提高功率因數。最後以平均電路模型,分析雙負載不平衡對於功率因數的影響,以磁滯控制法實現半橋式功率因數修正器之功因修正功能,並實際製作一電路與理論分析結果作一驗證,其結果顯示雙輸出電壓確實可達到平衡與理論設計符合。
The subject of this thesis is mainly related to compensation strategies of the output voltage imbalance on the half-bridge (HB) boost-type power factor corrector (PFC). First, the voltage imbalance of a HB PFC circuit is analyzed using the averaged circuit model. A DC component is injected in the input current to eliminate the output voltage imbalance, and this DC component is proportional to the difference between two output voltages. Also, the averaged circuit model is used to analyze the power factor for imbalanced dual loads. Finally, the hysteresis control method is employed to implement power factor correction in this thesis, and experiment results conform to the theoretical analysis.