Semi-Newton load flow algorithms in transient security simulations

This paper describes the results of an investigation concerning the idea of modify/relaxing the Newton-type transient load flow algorithms, implemented to achieve computationally more efficient load flow solutions in the transient security studies. Relaxing the coupling between MW and MVAr transient flows, and also the coupling between V and θ in the Jacobian matrix, including the complete decoupling, is studied. The algorithms were tested on the IEEE 18- and 68-node systems, showing improvements in computation speed and convergence and memory characteristics