Optimal Placement of Reactive Power Supports for Transmission Loss Minimization: The Case of Georgian Regional Power Grid

In this paper, a method to evaluate the optimal placement of reactive power support for minimization of transmission system losses based on a traditional cost-benefit analysis is proposed. The costs considered are economic costs associated with reactive power sources. The benefits from reactive power supports are defined as the reduced generation costs due to reduced losses as well as other quantifiable benefits, such as reduced total system cost. The dispatch costs could be reduced due to the fact that power generation schedules can be changed by increased transmission capability in the network which will allow for more generation from cheap sources to be delivered to the load centers. The benefits can also stem from the fact that more energy can be sold to the customers which would increase the sales (and thus profits) due to higher transmission capacity. The benefits will be worked out against the costs which will show the economic justification of the investments in reactive power sources. The method is based on an optimal power flow (OPF) framework which will be solved iteratively to arrive at the optimal solutions. The Georgian regional power grid is used in the simulation study to illustrate the method.