An Efficient Method for Undervoltage Load Shedding

This paper analyses the Thevenin equivalent characteristics of voltage instability by the P-V curve at the load buses. The situation and the time for load shedding are determined by identifying the weakest bus in the network by means of a voltage instability proximity index (VIPI). The index is defined by estimating Thevenin equivalent parameters using the online power flow technique. Load shedding amount is determined based on the load control of demand side management (DSM). The proposed algorithm of the efficient UVLS scheme is tested to show its effectiveness by an actual power network in China.

[1]  Liu Zhuo A Simple and Direct Method of On-line Tracking Thevenin Equivalent Parameters of Load Node , 2006 .

[2]  I.A. Hiskens,et al.  MPC-Based Load Shedding for Voltage Stability Enhancement , 2005, Proceedings of the 44th IEEE Conference on Decision and Control.

[3]  I.A. Hiskens Load as a controllable resource for dynamic security enhancement , 2006, 2006 IEEE Power Engineering Society General Meeting.

[4]  S.-J.S. Tsai,et al.  Adaptive undervoltage load shedding relay design using Thevenin equivalent estimation , 2008, 2008 IEEE Power and Energy Society General Meeting - Conversion and Delivery of Electrical Energy in the 21st Century.

[5]  Udaya Annakkage,et al.  A strategy for undervoltage load shedding in power systems , 1998, POWERCON '98. 1998 International Conference on Power System Technology. Proceedings (Cat. No.98EX151).

[6]  Allen J. Wood,et al.  Power Generation, Operation, and Control , 1984 .

[7]  Liu Zhuo RESEARCH ON PARAMETERS DRIFT PROBLEM IN TRACKING THEVENIN EQUIVALENT , 2005 .

[8]  Gerard Ledwich,et al.  Studies in System Thevenin Impedance Estimation from Normal Operational Data , 2003 .

[9]  L.Y. Seng,et al.  Innovative Application of Demand Side Management to Power Systems , 2006, First International Conference on Industrial and Information Systems.