VOLTAGE CONTROLLER FOR SYNCHRONOUS ELECTRIC MACHINES

An improved voltage controller for a synchronous electric machine of the type including a voltage controller including a controlled rectifier coupled thereto which is optimally matched to the parameters of the machine for its non-loaded condition. The improvement comprises a modulator coupled to the excitation winding and the controller of the machine, for generating a control signal which is proportional to the cosine of the load angle of the machine. The modulator modulates any output signal generated by the voltage controller of the machine according to the generated control signal. A voltage compensator coupled to the modulator generates a voltage compensation signal which is proportional to the current induced in the stator winding of the machine by the load applied thereto. The compensator also adds the compensation signal generated to the modulated output signal of the controller, which signals in combination form the voltage control input signal to the controlled rectifier of the machine and increase the current in the excitation winding of the machine in response to a load applied thereto, and thereby compensate for the reaction produced by the current induced in the stator winding of the machine by the load.