Definition: Automated Capacitors
Capacitors can increase the voltage on a distribution circuit by providing reactive power (often referred to as volt-amperes-reactive or VArs). Capacitor banks are switched in discrete steps, either manually, or in response to the voltage at the location where they are connected; typically, distribution capacitor banks are switched in a single step. If the voltage falls too far below the set point, the capacitor is switched in to raise the voltage. If the voltage rises too high above the set point, the capacitor is switched out to lower the voltage. Automated capacitors can be switched in coordination with other voltage control devices with signals from local sensors, distribution automation systems, or grid control systems. Such capacitors can be installed as automated devices or existing equipment can be retrofitted with controls and communications. The degree of automation depends on the controls and communications system implemented.