- 學位論文
高降壓轉換器之實用化探討
Investigation on the Practical Use of a High Step-down Converter
摘要
近年來，隨著環保意識抬頭，節能減碳已成最重要之課題，為此，再生能源之開發以及得以降低傳輸損失之直流供電，將成為當前因應之主要對策。隨著再生能源發電之蓬勃發展，在最近數年內，結合再生能源之直流微電網極可能大幅增加。 以美日等先進國家之發展趨勢而言，已嘗試地於試驗性之微電網或試驗性模型屋，進行直流供電。同時為了因應直流供電之時代的來臨，日常生活之電器產品的走向，將配合直流供電予以設計。一般直流供電將由直流匯流排之300VDC經各種轉換器供應電力予工、商業以及一般家庭之電氣設備使用。而所有電機以及電子產品所需之控制電源，極可能由直流匯流排之300VDC經高降壓轉換器[1]~[3]直接變換後供應。 雖然高降壓轉換器之使用需求將日益增大，但是高降壓轉換器於實用化技術的相關研究報告與參考文獻卻極為罕見。因此，本研究將針對適合高降壓之順向式轉換器進行實用化技術的探討。 在以維持電路架構之簡易性，因而得以避免電路可靠度之下降為前提，藉由軟切換技術[4]~[5]以減少切換損失，或是利用MOSFET構築同步整流電路[6]~[10]，甚至建構倍流電路[11]~[12]，以降低導通損失，提升電路效率。同時使用合適之減震電路[13]~[20]，如RCD減震電路[21]~[23]或LD減震電路[24]等，提升電路效率並抑制因寄生元件而產生之突波和雜訊，因而獲致實用性良好之高降壓轉換器。
並列摘要
Owing to the advent of energy-shortage era, enlarging the utilization of renewable energy and constructing DC transmission and distribution lines will be the mainstream countermeasures to solve the energy crisis. As vigorous development of renewable energy is growing in recent years, a significant increase in DC micro grids linking renewable energy will be most likely to be observed in the coming years. Since full DC power distribution will be realized sooner or later, all electrical appliances and electronic products should be designed in DC base to cope with DC power supplying. Generally in this case, bias power and drive power of control circuit are provided by a high step-down converter, which is directly supplied with the interconnected voltage (300VDC for residence) of distribution line. The number of the high step-down converter will be extremely large, however, almost no reference paper concerning practical technology of step-down converter is found so far. Since under high step-down condition, efficiency will become troublesome, besides, utilization rate of switch will not be improved easily. On the other hand, surge, noise and reliability are also important issues. All of the issues should be solved for the practical use of this converter. Keeping circuit configuration as simple as possible is used to maintain the reliability of the converter very well. Under this condition, some techniques, such as soft switching, synchronization rectification, current doubler etc. can be used to decrease power loss and improve efficiency. Further, appropriate snubber can be used for suppressing surge and noise and improving efficiency. Accordingly a high step-down converter with good practicability can be obtained.