What is the primary role of a voltage regulator?

The primary role of a voltage regulator is to maintain a constant voltage level and prevent overvoltage. Voltage regulators are essential components in electrical systems that ensure the voltage supplied to electrical devices remains stable and within a specified range, regardless of fluctuations in the input voltage or load conditions.

This stability is crucial for the safe and efficient operation of electrical equipment, as many devices are sensitive to voltage changes. Overvoltage can lead to damage or reduced lifespan of the equipment, so the voltage regulator continuously monitors and adjusts the voltage output to protect the load. It achieves this through various methods, including series regulation, shunt regulation, or utilizing switching techniques in modern designs.

The other options pertain to different functions that voltage regulators do not primarily serve. For instance, increasing voltage levels is a function of a transformer or step-up converter rather than a regulator. Measuring current relates to ammeters or meters, which are not the role of voltage regulators. Disconnecting circuits due to low voltage typically involves protective devices such as relays or circuit breakers, not a voltage regulator. Thus, the answer focuses on the critical function of a voltage regulator in maintaining voltage stability.