Bus sensitivity to load-model parameters in load-flow studies

This paper considers the sensitivity of the load-flow solution to model parameters when load models of the exponential form are incorporated. Several test systems are considered. Computational experience with Newton´s method applied to solve the resulting load-flow problems is given. The effects of model parameters and system characteristics on the convergence of the method and on the resulting solutions are highlighted. Our results indicate that the higher values of model parameters yield more significant changes in the load-flow results from the conventional load-flow solution. For the same system, the effect of load modelling is more pronounced at heavier loads than at normal loads. For systems with high capacitive loads, the effects of model parameters are more significant. We also conclude that Newton´s method fails to converge for cases where the capacitive effect is high combined with a high reactive-power model exponent even though the application of Newton´s method to the conventional problem is successful.