Look-ahead approach to power system loadability enhancement

The paper presents a new look-ahead approach to loadability (static voltage stability limit) enhancement of power systems. Most researchers have used approaches that optimise the reactive losses/reactive reserves based on present operating condition. Although reactive power optimisation based on such strategies may result in an increase in distance to collapse, such an increase may not be sufficient. This is because a key factor in loadability enhancement is the reflection of load increase scenario in the optimisation problem. The proposed approach achieves this objective without making the problem too complex. The objective is to minimise reactive power losses near critical loading such that constraints at both loadings are satisfied. Results for two sample test systems, IEEE 30 bus and IEEE 14 bus have been obtained with local as well as look-ahead optimisation strategies to demonstrate the superiority of the latter over the former.