A Wide-Area Measurement Systems-Based Adaptive Strategy for Controlled Islanding in Bulk Power Systems

Honglei Song,Kui Wu,Junyong Wu

doi:10.3390/en7042631

Honglei Song, Kui Wu + Show 1 more

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https://doi.org/10.3390/en7042631

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Journal: Energies	Publication Date: Apr 23, 2014
Citations: 42	License type: CC BY 4.0

Affiliation: University of Victoria, Beijing Jiaotong University

Abstract

Controlled islanding is the last countermeasure for a bulk power system when it suffers from severe cascading contingencies. The objective of controlled islanding is to maintain the stability of each island and to keep the total loss of loads of the whole system to a minimum. This paper presents a novel integrated wide-area measurement systems (WAMS)-based adaptive controlled islanding strategy, which depends on the dynamic post-fault trajectories under different failure modes. We first utilize an improved Laplacian eigenmap algorithm (ILEA) to identify the coherent generators and use the slow coherency grouping algorithm to guarantee coherent stability within an island. Using the identification result, we then define the minimum coherent generator virtual nodes to reduce the searching space in a graph and utilize the k-way partitioning (KWP) algorithm to obtain a preliminary partition of the simplified graph. Based on the preliminary partition, we consider the direction of power flow and propose a variable neighborhood heuristic searching algorithm to search the optimal separation surfaces so that the net imbalanced power of islands is minimized. Finally, the bidirectional power flow tracing algorithm and PQ decomposition power flow analysis are utilized to determine the corrective controls within each island. The test results with the New England 39-bus system and the IEEE 118-bus system show that the proposed integrated controlled islanding strategy can automatically adapt to different fault modes through generator coherency identification and effectively group the different coherent generators into different islands.

Highlights

With the expansion of large interconnected power grids and the regional integration of large-scale power systems, along with the increasingly diverse power transmissions driven by market competition, the stability and safety operation of the bulk power system is faced with serious challenges.Specially, severe disturbances, such as earthquakes, hurricanes, human operation errors and malicious attacks, may make the power system unstable and even trigger cascading outages
We present a novel integrated wide-area measurement systems (WAMS)-based adaptive controlled islanding strategy
We propose improved Laplacian eigenmap algorithm (ILEA) to identify coherent generators

Summary

Introduction

With the expansion of large interconnected power grids and the regional integration of large-scale power systems, along with the increasingly diverse power transmissions driven by market competition, the stability and safety operation of the bulk power system is faced with serious challenges Severe disturbances, such as earthquakes, hurricanes, human operation errors and malicious attacks, may make the power system unstable and even trigger cascading outages. In the Northeastern United States and Canada blackout on 14 August 2003 [1], the outage was initially triggered in Ohio, but spread quickly to the whole eastern region It affected an area having over 50 million people and 61,800 MW of electric load in the states of Ohio, Michigan, Pennsylvania, New York, Vermont, Massachusetts, Connecticut and. Subsequent faults led to the breaking down of the whole power system

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