Reactive Compensation Planning in Unbalanced Electrical Power Systems

This research focuses on finding the optimal location of reactive compensation in an unbalanced electrical power system (EPS). An EPS is named unbalanced when there is uncertainty in the behaviour of the power demand, which causes changes in the voltage profile and angle of each of the electrical power phases. For this reason, using reactive compensation will improve the voltage profiles and the magnitudes of reactive power in the transmission lines. The proposed methodology uses the optimal AC power flows as a basis, which is applied to each power phase and, through this methodology, the operating conditions of the EPS are determined. Then, based on the voltage profiles of each power phase, it was possible to determine the critical nodes of the system, so that afterwards, through heuristics, it was possible to find the optimal location of the reactive compensation that independently meets the needs of each phase. To evaluate the proposed methodology, the IEEE test systems of 9, 14, 30 and 118 bus bars were used, as well as the 230 kV ring of the Ecuadorian transmission system. Finally, using the proposed methodology, it was possible to independently compensate for each of the power phases, rectifying the unbalanced voltage profiles that appeared in the EPS.