V 1, the slack bus voltage being fixed is not required to be updated. During each iteration voltages at buses i = 2, 3, …, n are sequentially updated through use of Eq. (6.41) are the most recently calculated (updated) values for the corresponding buses. The voltages substituted in the right hand side of Eq. During the course of any iteration, the revised voltage at the ith bus is obtained as follows: These values are then updated through an iterative process. The slack bus voltage being specified, there are (n – 1) bus voltages starting values of whose magnitudes and angles are assumed. We shall see later that the method can be easily adopted to include PV buses as well. To explain how the Gauss Seidel Method is applied to obtain the load flow solution, let it be assumed that all buses other than the slack bus are PQ buses.
