Abstract: A method for testing a power generation system includes measuring current generated by a generator comprising a field winding operable to control current generated by the generator by controlling current applied to the field winding. Voltage output by the generator is measured. The measured current and the measured voltage are conducted to a processor connected to the generator. The processor to varies at least one of the measured current and the measured voltage. A field output of the processor is coupled to the field winding of the generator. A response of the power generation system to the varied measured current or measured voltage is determined.