以最小電壓法設計串聯不平衡電壓調整器

Abstract

現今科技產業的蓬勃發展，各產業用戶對電力品質的要求也日趨嚴格。傳統的改善電力品質的方法為裝設不斷電供電系統（Uninterruptible Power Supplies:簡稱UPS），然而這種方式仍然有許多缺點；包括了電池成本上的問題與電池本身使用上與定期保養上的維護成本問題，這都造成了很大的支出。本文中將介紹另一種較經濟的解決方式，即以串聯式動態電壓調整器(DVR)來達到對不平衡配電系統之電壓調整的目標。 傳統的DVR具有不平衡系統的電壓調整、不平衡修正等等電力品質改善的功能，一般常見的方法是採用純虛功的補償方式，使用實功來做電壓補償的方式是很少見的，而在本論文中將提出一種包含實功率的電壓的補償方式，且會對兩種電壓補償方式作比較，分析其優缺點。本論文會經由模擬與實驗及結果證明論文內提出演算法的實用性，更進一步說明兩種補償方式的差別，包括補償能力與功率損失的差別，這間接說明實功率的投入的確有其優點與必要性。 本論文所提出的電壓補償方式為一最小電壓補償方式，目標為希望藉由一較小的投入電壓來減少補償器所需投入的視在功率，進而減少補償器設置容量。

With the development of high technology industries, the requirements for power quality become strict. The conventional approach to ensure the continuous supply of high quality power to sensitive loads is to use uninterruptible power supplies (UPS). However, this equipment is costly and batteries require maintenance. Consequently, this thesis presents a more economic solution to this problem, that is, the usage of Dynamic Voltage Regulator (DVR). By using Dynamic Voltage Regulator, the goal to regulate unbalanced distribution system voltage can be achieved. Traditional DVR can be applied to regulate bus voltage and improve unbalance in a distribution system. Usually, pure reactive power compensation is adopted. The use of real power compensation is rare. In this thesis , a new method which employ real power compensation as well as reactive power compensation is presented for the design of a DVR. The effectiveness of the proposed DVR is compared with traditional DVRs which employ only reactive power compensation. Simulation and experiments are conducted in order to demonstrate the feasibility of the proposed algorithm. compensation capability and losses are the proposed DVR are evaluated based on simulation and experimental results. From the simulation and experimental results, it is concluded that bus voltage cab be regulated by the proposed DVR with minimum injection voltage and minimum capacity.