Optimal Size and Location of Capacitors on Power Distribution Lines

Shunt capacitor banks are used on power distribution feeders to reduce losses and regulate the voltage level. The decrease in transmission line current also leads to an increase in the amount of demand that can be supplied without increasing the size of the conductors. In order to maximize the benefit of adding capacitor banks to the distribution feeders, the optimal size and location of the capacitors must be determined. This paper presents a novel optimal control approach to both regulate the voltage drop and reduce the copper loss. A cost function that penalizes both energy losses and voltage drop is developed. The optimal size and location of capacitors can be found using the optimal control solution. Computer simulation results are compared with existing methods of determining the optimal size and location of capacitors. Our approach improves on current methods by providing flexibility to both regulate voltage levels and reduce losses.