What drives the tap changer switch in a regulator?

The tap changer switch in a voltage regulator is driven by a motor. This motor is responsible for automatically moving the tap changer to adjust the voltage levels as needed based on the load conditions or system requirements. The motorized mechanism allows for precise control and quick response to changes in the electrical system, enabling the regulator to maintain the desired voltage level efficiently.

In this context, while other options such as manual control or hydraulic pumps are used in various applications, they are not the primary means of driving the tap changer in a voltage regulator. Manual control would require operator intervention, which is less efficient and not suitable for automatic voltage regulation. Hydraulic pumps and pneumatic actuators, while useful in other mechanisms, typically do not apply to the standard operation of tap changers in voltage regulators where electric motor systems are the norm for reliability and speed.