Voltage fluctuation refers to the variations in electrical voltage levels within a power supply system. These changes can occur due to various factors, such as changes in electrical load, equipment malfunctions, or disturbances in the power grid. Voltage fluctuations can affect the performance of electrical devices, potentially leading to inefficiencies or damage. In residential and industrial settings, voltage fluctuations can cause lights to flicker or machinery to operate improperly. To mitigate these issues, devices like voltage stabilizers or uninterruptible power supplies (UPS) can be used to maintain a consistent voltage level, ensuring the reliable operation of electrical equipment.