Which statement best describes the voltage regulator's role in a generator?

Which statement best describes the voltage regulator's role in a generator?

• A. It controls the field strength
• B. It controls the rotor speed
• C. It sets the generator frequency
• D. It opens or closes the main contactor

Answer: (A)

The voltage regulator controls the generator’s field strength to keep the output voltage steady. It senses the terminal voltage and adjusts the excitation current in the generator’s field winding: increasing excitation raises voltage, while decreasing excitation lowers it. This keeps the voltage within limits as the load or engine speed changes. It does not set rotor speed or generator frequency (that depends on engine RPM and the machine’s pole count), and it does not operate the main contactor.

The voltage regulator controls the generator’s field strength to keep the output voltage steady. It senses the terminal voltage and adjusts the excitation current in the generator’s field winding: increasing excitation raises voltage, while decreasing excitation lowers it. This keeps the voltage within limits as the load or engine speed changes. It does not set rotor speed or generator frequency (that depends on engine RPM and the machine’s pole count), and it does not operate the main contactor.