Generator system and control method

An engine-driven generator system comprising:

• an internal combustion engine;
• a generator assembly coupled to and driven via the engine, and having an electric generator, field windings, and a voltage rectifier collectively producing a direct current (DC) generator output voltage;
• a DC voltage bus connected to the voltage rectifier and having an electrical potential that is equal to the generator output voltage;
• and
• a controller having an inner control loop configured to input a field duty cycle signal to the field windings in response to an adjusted voltage control signal, and an outer control loop providing a torque-based voltage control signal as an input to the inner control loop in response to a commanded engine torque and an estimated generator torque, such that an output torque of the electric generator is directly controlled via operation of the outer control loop;
• wherein the inner control loop is configured to calculate the adjusted voltage control signal as a difference between the torque-based voltage control signal and the generator output voltage.