具負載阻抗估測之三相四線式換流器研製

Design and Implementation of Three-Phase Four-Wire Inverter with Load Impedance Estimation

李昭慶(Lee, Chaoching)

指導教授 ： 吳財福

國立中正大學/工學院/電機工程學系/碩士(2012年)

摘要

本研究提出具寬廣電感變化與負載阻抗估測之三相四線式換流器的研製，此三相四線式換流器可滿足併網型與獨立型之再生能源交流供電系統。於獨立型系統中，由於有中性臂的存在，換流器可穩定三相不平衡或非線性負載輸出之弦波電壓。藉由負載阻抗之估測，控制器可以準確地追蹤交流弦波電壓準位，且允許寬廣的電感值變化，降低鐵心體積與成本。本控制法以兩相調變法為基礎，結合了無拍差控制(Dead-beat Control)和負載阻抗估測，負載阻抗的估測更導入了重複性控制(Repetitive Control)的概念來減少估測的誤差，以確保系統的穩定性。最後，本研究將控制法以 Matlab 模擬並實作一部10 kVA三相四線式換流器來驗證所提方法的可行性。

關鍵字

三相四線式換流器 ； 不斷電系統

並列摘要

This thesis presents design and implementation of a three-phase four-wire inverter with load impedance estimation. The inverter can fulfill both grid-connected and stand-alone mode operations. In the stand-alone mode, the inverter with a neutral leg can generate sinusoidal output voltage for unbalanced load and nonlinear load. With the load impedance estimation, the controller can track the sinusoidal reference voltage accurately, and the inverter is allowed to have a wide inductance variation, reducing core loss and size significantly. The control law is derived based on the two-phase modulation (TPM) scheme with a dead-beat control and on-line load impedance estimation, in which the repetitive control concept is adopted to reduce the estimation tolerance. Computer simulation and experimental results from a 10 kVA three-phase four-wire inverter have been presented to confirm the feasibility of the inverter.

並列關鍵字

three phase four wire inverter ； UPS

參考文獻

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