MPC-Based Load Shedding for Voltage Stability Enhancement

Impending voltage collapse can often be avoided by appropriate control of loads. However the traditional form of load control (shedding) is unpopular due to the resulting consumer disruption. Advances in communications and computer systems allow more selective load control though. Individual loads that are sacrificeable in the short-term can be switched with minimal consumer disruption. The paper considers the use of such non-disruptive load control for improving voltage stability. A control strategy that is based on model predictive control (MPC) is proposed. MPC utilizes an internal model to predict system dynamic behaviour over a finite horizon. Control decisions are based on optimizing that predicted response. MPC is a discrete-time form of control, so inaccuracies in predicted behaviour are corrected at the next control interval. A standard 10 bus voltage collapse example is used to illustrate this control strategy.

[1]  D. Lefebvre,et al.  Load shedding controllers against voltage instability: a comparison of designs , 2001, 2001 IEEE Porto Power Tech Proceedings (Cat. No.01EX502).

[2]  L. Petzold,et al.  Numerical methods and software for sensitivity analysis of differential-algebraic systems , 1986 .

[3]  Ian A. Hiskens,et al.  Trajectory Sensitivity Analysis of Hybrid Systems , 2000 .

[4]  Ian A. Hiskens,et al.  Power system modeling for inverse problems , 2004, IEEE Transactions on Circuits and Systems I: Regular Papers.

[5]  James B. Rawlings,et al.  Tutorial overview of model predictive control , 2000 .

[6]  C. W. Taylor.  Concepts of undervoltage load shedding for voltage stability , 1992 .

[7]  Paul I. Barton,et al.  Modeling, simulation and sensitivity analysis of hybrid systems , 2000, CACSD. Conference Proceedings. IEEE International Symposium on Computer-Aided Control System Design (Cat. No.00TH8537).

[8]  Frank Allgöwer,et al.  State and Output Feedback Nonlinear Model Predictive Control: An Overview , 2003, Eur. J. Control.

[9]  Stefan Arnborg,et al.  On undervoltage load shedding in power systems , 1997 .

[10]  M. Kintner-Meyer,et al.  Innovative developments in load as a reliability resource , 2002, 2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309).

[11]  D. Backer.  Technologies for fast load control , 2002, 2002 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.02CH37309).

[12]  Basil Kouvaritakis,et al.  Constrained receding horizon predictive control for nonlinear systems , 2002, Autom..

[13]  Thierry Van Cutsem,et al.  Voltage Stability of Electric Power Systems , 1998 .

[14]  P. Kundur,et al.  Power system stability and control , 1994 .

[15]  Peter W. Sauer,et al.  Power System Dynamics and Stability , 1997 .

[16]  Goran Andersson,et al.  Stability assessment and emergency control method using trajectory sensitivities , 2003, 2003 IEEE Bologna Power Tech Conference Proceedings,.