Automatic Voltage Control (AVC) is a system used in electrical power networks to maintain a consistent voltage level. It automatically adjusts the output of generators and transformers to ensure that the voltage remains within specified limits, which is crucial for the stability and efficiency of the power supply. AVC systems utilize sensors to monitor voltage levels and control devices like transformers and capacitor banks to make real-time adjustments. This helps prevent voltage fluctuations that can damage equipment and disrupt service, ensuring a reliable electricity supply for homes and businesses.