A new approach to optimal power flow with phase shifter

This paper presents an integrated approach to study the optimal power flow (OPF) with phase shifter for alleviating line overloads. It is noted that the general OPF calculations are hourly based and the control variables of OPF are continuous. However, the calculations of phase shifter are daily based, and the variable of phase shift is discrete as well as the numbers of allowable adjustments for each phase shifter per day are also discrete. The proposed scheme uses the rule-based method to bridge the problems. The hourly based OPF solution will be sent to rule based system to check the phase shifter constraints. Meanwhile, the rule based system will transfer the available phase shifter control as input to OPF. The OPF hourly based is solved by the extended quadratic interior point method. The proposed approach is tested on the IEEE 30-bus system with 4 phase shifters.