How does capacitor placement and switching affect the voltage profile and losses on a distribution feeder?

Capacitors are used in distribution systems to provide reactive power compensation, which directly affects the voltage profile and losses on the feeder. Inductive loads, like motors, consume reactive power, causing the voltage to drop along the feeder. Capacitors inject reactive power into the system, counteracting the inductive load and supporting the voltage. Proper capacitor placement is crucial. Placing capacitors near the load centers is most effective in improving the voltage profile and reducing losses. Placing them too far upstream may not adequately address the voltage drop at the end of the feeder. Capacitor switching affects the voltage profile and losses dynamically. Switching capacitors on during periods of high load and switching them off during periods of low load helps to maintain a relatively flat voltage profile. Switching too frequently can cause voltage fluctuations and stress on the equipment. Improper capacitor placement or switching can lead to overvoltages or undervoltages, harming customer equipment and potentially violating voltage standards. Switching capacitors can also reduce losses by reducing the current flow in the feeder. By providing reactive power locally, the current that must be supplied by the substation is reduced, lowering I²R losses in the conductors. The optimal capacitor placement and switching strategy depends on the load profile, feeder characteristics, and system configuration. Sophisticated software tools are often used to determine the best capacitor locations and switching schedules.