ECONOMICAL DESIGN OF SERIES CAPACITOR COMPENSATION FOR LONG POWER TRANSMISSION-SYSTEMS

Series capacitor compensation has been found to considerably increase the power carrying capacity of AC long power transmission systems. This paper presents a mathematical model and an analytical procedure for finding the economical degree of series capacitor compensation. Two analytical approaches are described: the first is based on minimizing the energy transmission cost of 1 kWh to be transmitted over the compensated line, and the second is based on maximizing an objective function defined by the difference between the equivalent cost of the increase in the operating level of the power transmitted over the line and other costs associated with the line including the costs of series capacitors and extra power losses due to the higher current carried over the compensated line. Results of the application of the proposed procedure to a sample 500 kV transmission line are provided. The effects of different electrical parameters on the optimal (economical) compensation conditions are also considered.