利用有容錯能力之分散式委員會代理人來解決電網自動復電問題

Applying Distributed Committee-Based Agents with Fault Tolerance to Power Restoration Problems

黃翊瑋(Yi-Wei Huang)

指導教授 ： 蘇豐文

國立清華大學/電機資訊學院/資訊系統與應用研究所/碩士(2012年)

摘要

隨著科技的進步，工商業的興盛，電力系統無法正常運作對社會所造成的損害與日俱增，復電問題也逐漸受到重視，如何在最短的時間內以最低成本恢復斷電區域的電力系統便成為近年來相當重要的議題。
本論文將一般電力網路的每一個元件皆視為一個智慧型代理人(例如：發電機、開關、電力區域)，並以委員會協商機制為出發點，建構出一個智慧代理人的分散式復電系統。一旦發生斷電問題，本系統將可以自動偵測並隔離該斷電區域，同時藉由區域委員會協商機制，開關代理人在自己所屬的委員會內分享彼此資訊、自行協商，以最小開關變動數為首要目標、最大復電量為次要目標，找到候選的區域解，最後透過階層式訊息傳送與決策機制，跳脫可能受限於區域最佳解的問題，找到全域最佳解；此外，我們更考量了電壓下降問題並加入了二次轉供機制讓實驗結果更能符合現實狀況，並在此系統上設計了另一層容錯機制，以確保當開關代理人本身出問題無法運作時，本系統在訊息部分遺漏的情況下依舊能繼續運作，不會讓系統完全停擺以至於無法解決復電問題。
我們將在實驗中以不同的電力網絡拓撲為測試對象，比較本論文提出之決策機制與傳統方式甚至能源領域當中復電的標準方式之間的不同與差異，如何以低成本高效率來解決此問題；此外，我們也將藉由實驗測試對此系統本身的容錯機制，証明此系統在不同程度的毀損上，依舊能有可接受的能力表現。

關鍵字

分散式系統 ； 能源系統 ； 復電問題 ； 多代理人系統 ； 容錯機制

並列摘要

Due to the rapid development of technology and the rise of industry and economics, the damage to the society caused by the failure of power system becomes larger and larger. How to recover the power system from black-out in the shortest time with minimum cost has become an important issue in recent years.
In this thesis, we will treat components of the power grid as intelligent agents, for instance, feeders, switches and power demand areas, and then construct a distributed power restoration system with intelligent agents based on concept of committee-based negotiation. Once the power system of an area fails, the system we proposed will automatically detect and isolate this area, and begin the solution finding processes. Base on the committee-based negotiation mechanism, the switch agents will share their information to the committee members of the committee which they belong to, negotiate with each other, and find out a candidate local solution depending on two major objective functions which are minimizing the number of switch changes and maximizing the amount of power demand to be restored. Finally, we can escape from being trapped in a local optimal solution and find the globally optimal solution with the hierarchical message passing and by the exhaustive constraint satisfaction decision making mechanism we proposed. Besides, we further take the problem of voltage drop into account and implement the mechanism of load-transfer to let the solution be much stable in practice. We also design a fault-tolerance mechanism on our restoration system to assure that our restoration system can work even when limited number of agents failed. Although the solution generated maybe degraded due to the missing of some information, but the system will not directly shut down and let the emergent problem of power system be unsolved. Otherwise, it must cause larger damage to the society.
We will take different power grids and benchmark problems from power restoration research literatures as the test samples of our experiments and compare our multi-agent approach to the traditional methods. Besides, we also evaluate the fault tolerance ability of our restoration system to see how it performs under different degrees of failure in power restoration agents.

並列關鍵字

distribution system ； power system ； power restoration ； multi-agent system ； fault tolerance

參考文獻

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