以系統辨識法完成一新穎過電流保護裝置特性與其實務運用

A Novel Over-Current Protective Device Characteristic Developed by Eigensystem Realization Algorithm and Its Practical Applications

吳峯日(Feng-Jih Wu)

指導教授 ： 周至如 ； 陸茵

國立臺北科技大學/電資學院/電機工程系所/博士(2013年)

摘要

在電力系統保護協調研究領域上，正確表達典型過電流保護裝置動作特性，是個重要關鍵。本文首次提出一種新穎方法，用來擬合過電流保護裝置動作特性，以決定其動作特性參數。此方法以ERA演算法(Eigensystem realization algorithm)為基礎，採在狀態空間模型(State-space model)下擬合過電流保護裝置動作特性。此動態系統模型優於傳統廣泛被使用的靜態動作特性，可以用來擬合傳統典型和依系統需求的非典型的過電流保護裝置動作特性，且能達到相當高的準確度。本研究選擇典型及非典型過電流保護裝置動作特性曲線等共27條，進行擬合，以最大絕對值誤差做為評估所需擬合的組成成份數量，綜合找出一多功能方程式來表示他們的特性。然後，建議此多功能方程式為一新穎彈性過電流電驛動作特性的模型，並在此動作特性模型條件下，列舉多個實例，描述如何運用及改善在二次輸電系統及配電系統的過電流保護協調問題，並說明其具有其他多項額外的運用。

關鍵字

曲線擬合 ； 特徵系統實現演算法 ； 萬用型過電流電驛 ； 多功能方程式 ； 誤動作

並列摘要

Accurate models of the characteristics of typical inverse-time overc-urrent (OC) protective devices play an important role in the protective coordination schemes in the sub-transmission and distribution systems. The first dissertation presents a novel approach to determine the OC protective device parameters. The approach is based on the Eigensystem Realization Algorithm (ERA) which generates a state-space model to fit the characteristics of OC protective devices. Instead of the conventional characteristic curves, the dynamic state-space model is a more accurate fit of the OC protective device characteristics. This dissertation describes the detail procedure of decomposing the characteristic curve into smooth components and oscillation components. For demonstrations, 27 characteristic curves are selected from both typical and non-typical OC protective devices for curve-fitting. The numbers of fitting components required are determined by the desired level of maximum absolute values of errors for the fitting equations. Furthermore, all fitting equations for the characteristics of OC protective devices can be replaced by one single equation representing a universal OC relay which can be used to solve the problems of over-current coordination and the like in the sub-transmission and distribution systems.

並列關鍵字

Curve fitting ； Eigensystem Realization Algorithm ； Universal OC relay ； Versatile equation ； Sympathy tripping

參考文獻

1. A. Conde, E. Vazquez, "Application of a proposed overcurrent relay in radial distribution networks", Electric Power Systems Research, Vol.81, No.2, February 2011, pp.570-579.

3. IEEE Committee Report, "Computer representation of overcurrent relay characteristics", IEEE Transactions on Power Delivery, Vol.4, No.3, July 1989, pp.1659-1667.

4. S. Chan, R. Maurer, "Modeling Overcurrent Relay Characteristics", IEEE Computer Applications in Power, Vol.5, No.1, 1992, pp.41-45.

5. IEEE PSRC Committee, "IEEE Standard Inverse-Time Characteristic Equations for Overcurrent Relays", IEEE Transactoions on Power Delivery, Vol.14, No.3, July 1999, pp.868-872.

6. H.K. Karegar, H.A. Abyaneh, M. Al-Dabbagh, "A flexible approach for overcurrent relay characteristics simulation", Electric Power Systems Research, Vol.66, No.3, September 2003, pp.233-239.