電力系統過電流電驛保護協調最佳化之研究

Optimal Coordination of the Overcurrent Relay Protection of Power Systems

李振弘(Cheng-Hung Lee)

指導教授 ： 陳昭榮

國立臺北科技大學/電資學院/電機工程系博士班/博士(2013年)

摘要

本論文旨在探討過電流保護電驛(Overcurrent Relay- OCR)之保護協調設定最佳化，以提供電力系統適應性保護。OCR做為電力系統保護歷史悠久，由電磁機械式、固態晶體式、微處理器式，到智慧型電子元件-Intelligent Electronic Device (IED)已經具備開放式通訊協定之網路通訊功能，且其構造由單相保護、單一功能電驛，到多相保護、多功能保護電驛等。過電流電驛始終扮演重要的供電系統保護角色。本文從OCR基本構造介紹、動作原理、演進發展，到保護協調計畫作業方法介紹，另外由於電力系統保護電驛數量眾多，上下游關係複雜，人工設定困難且耗時，需要重覆驗證等，適合使用最佳化方法以快速找出最佳的設定。因此使用基因演算法及免疫演算法於各種電力系統，包含輻射式配電、單環與多環互聯網網路系統，以執行保護協調最佳化設定過電流電驛。由於智慧型演算法適用於離散式運算，當使用不同特性曲線之OCR時可能發生特性曲線交叉，因此本文提出一種偏微分趨近法(Partial differentiations approach-PDA) 可以找出兩已知OCR曲線之最接近之座標點，含時間間隔及其電流值並驗證其最近點斜率，以確保無交叉。由於電力系統中央監控SCADA系統架構下的IED具有通訊連線調整設定值功能，因此本文亦提出一種適應供電系統尖離峰負載差異以致故障電流變化較大，影響OCR動作時間之電驛調整設定策略。研究的結果並以實例驗證最佳化的方法確實可以找出OCR保護協調的最佳設定結果，並可應用於各種複雜的電力系統保護以達到快速、準確、可靠及適應性保護之目的。

關鍵字

過電流電驛 ； 保護協調 ； 基因演算法 ； 免疫演算法 ； 智慧型電子元件

並列摘要

The dissertation is to research the optimal coordination of the overcurrent relay (OCR) protection of power systems for adaptive protections. OCR has long been the main device protecting power systems. These devices were originally based on electromechanical induction, and new device types were then developed based on solid-state, microprocessors and intelligent electronic devices (IED), with the protective features evolving from single phase units to multi-phase multi-functional units with communications and network SCADA control. Overcurrent relay with a single fundamental structure is cost-effective and selective, but the relay settings for each protective application should be carefully ranked and upstream to downstream protective isolation coordination should be considered to achieve adaptive protection. The research starting from introduction of the OCR fundamental theory, construction and development to the coordination works. The aim of this study is to investigate the optimal methodologies that can be used to locate the optimal settings of each relay in various power systems. Genetic algorithms and immune algorithms are adapted for application to protective relay coordination, and their performance is compared with the conventional method and with each other. The blind spots of optimal methods is discussed, a partial differentiation approach (PDA) is introduced to solve the problem, and the concept of the state-of-the-art application of the IED is discussed for the case of an adaptive load change. The results show that the proposed methods are able to find the optimal settings of overcurrent relays not only for radial type but also for complicated interconnected power systems, an important finding as it is often difficult to manually set and verify the complicated systems.

並列關鍵字

Overcurrent Relay ； Protective Coordination ； Genetic Algorithm ； Immune Algorithm ； IED

參考文獻

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