交流微電網之建模、控制策略與即時模擬

Modeling, Control Strategies, and Real-time Simulation for an AC Microgrid

余承育(Cheng Yu Yu)

指導教授 ： 張文恭

國立中正大學/工學院/電機工程學系/碩士(2015年)

摘要

近年來隨著能源價格不斷波動及越來越受到關注的環保永續概念，再生能源如太陽能、風力、水力、地熱等相關建設愈發受到重視。本論文整合了分散式能源及再生能源，增加再生能源的占比，透過先進的控制和管理來提供交流微電網良好的電力品質及可靠度。
本文利用Matlab/Simulink 來建立核能研究所之三相交流微電網的模型，並對微電網的併網、孤島模式切換和發電機控制進行模擬。此外，利用即時模擬器來驗證即時模擬和離線模擬的精確性及模擬時間。最後對案例結果進行分析、驗證所提出的控制策略及微電網模型的正確性。
本論文透過電力電子設備來操作分散式電源，使分散式電源在運作和控制上更靈活。在正常情況下，微電網與市電併聯，會利用實功/虛功控制(PQ control)，使各個分散式電源操作在最有效率的狀態，讓每個分散式電源都按照預設的功率進行輸出，負載端與發電端功率不同部分則由市電來提供，使電網供需平衡並且效率最高。當微電網與市電意外解聯時，儲能電池將切換成電壓/頻率控制(V/F control)，來維持微電網的電壓和頻率，依據電網狀況提供實功和虛功使電網供需平衡。在太陽能發電的部分，也加入了電壓/虛功控制(Volt/Var control)，可以根據電網狀況提供虛功讓電網電壓更穩定。

關鍵字

即時模擬 ； 電壓/虛功控制 ； 電壓/頻率控制 ； 實功虛功控制 ； 分散式

並列摘要

In recent years, due to energy prices fluctuating and environmental protection concerns, renewable energy sources such as solar, wind and hydro energy-related researches have attracted much attention. In this thesis, a microgrid integrated with renewable energy and other forms of distributed energy resources (DER) to increase the renewable energy penetration, and improve power quality and reliability through advanced control and management is under study.
The research in this thesis adopts Matlab/Simulink to create the INER microgrid models. Several conditions including grid-connected mode, islanding mode, and DG control are simulated. Moreover, this thesis performs that utilizing real-time digital simulator (RTDS) to compare the result and computation time between real-time and off-line simulations. Finally, the performance and effectiveness of the proposed control strategies for the microgrid are verified by the study cases.
The microgrid adopts power electronic devices to control DERs. These devices make the microsources more flexible in control and operation. Under the normal operation, a microgrid is connected to the utility grid, and each DER provides a preset power to the microgrid through active/reactive power control (PQ control). It also adds Voltage/Var control (Volt/Var control) to the solar system for providing suitable reactive power. These operations lead to every DER control in the most efficient condition. The power difference between supply and load will be supplied by utility grid to maintain the microgrid efficiency and balance. However, when the microgrid is disconnected from the utility grid due to faults, the storage system will change to voltage/frequency control (V/F control) in order to regulate the voltage and frequency of the microgrid. Such control action makes voltage magnitude stable.

並列關鍵字

Voltage/Frequency control ； active/reactive power control ； Distributed energy resource ； Voltage/Var control ； real-time simulation

參考文獻

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