Optimal Tap Configuration for Step-Voltage Regulators Applied to Residential Feeders

In the present paper, a centralized control method of the tap configuration for step-voltage regulators (SVRs) is proposed. First, the problem will be formulated: The power flow equations and the objective function with its constraints will be described for the studied system. Two different objective functions are defined for comparison purposes: On the one hand, the objective will be minimizing the deviations of voltages with respect to their rated values. On the other hand, the minimized voltage scenario is considered. These two cases are compared also to the case base in which there is no regulation. Aspects such as power injected to the grid, power losses and degree of unbalance are analyzed. Focusing on residential feeders, a complete 24-hour span will let us simulate several different load conditions. Moreover, by utilizing a general load model, instead of the constant power model (PQ), and by applying an accurate load demand prediction, more realistic results are achieved. The case studies are implemented in a modified version of the IEEE 123 Node Test Feeder, which includes additional and rearranged regulators.