Abstract

Three algorithms for reactive power optimization are proposed in this paper with three different objective functions. The objectives in the proposed algorithm are to minimize the sum of the squares of the voltage deviations of the load buses, minimization of sum of squares of voltage stability L-indices of load buses (ΣL²) algorithm, and also the objective of system real power loss (P_loss) minimization. The approach adopted is an iterative scheme with successive power flow analysis using decoupled technique and solution of the linear programming problem using upper bound optimization technique. Results obtained with all these objectives are compared. The analysis of these objective functions are presented to illustrate their advantages. It is observed comparing different objective functions it is possible to identify critical On Load Tap Changers (OLTCs) that should be made manual to avoid possible voltage instability due to their operation based on voltage improvement criteria under heavy load conditions. These algorithms have been tested under simulated conditions on few test systems. The results obtained on practical systems of 24-node equivalent EHV Indian power network, and for a 205 bus EHV system are presented for illustration purposes.

Submitted: April 21, 2006 · Accepted: July 3, 2006 · Published: September 28, 2006

Recommended Citation

Dhadbanjan, Thukaram and Yesuratnam, G. (2006) "Comparison of Optimum Reactive Power Schedule with Different Objectives Using LP Technique," International Journal of Emerging Electric Power Systems: Vol. 7 : Iss. 3, Article 4.
DOI: 10.2202/1553-779X.1338
Available at: http://www.bepress.com/ijeeps/vol7/iss3/art4