Patent ID: 7400117

Claim:
An electromechanical power transfer system that transfers power between a prime mover and a direct current (DC) electrical system, comprising: a permanent magnet machine (PMM) that has a permanent magnet (PM) rotor coupled to the prime mover, a stator with a multiphase alternating current (AC) winding coupled to an AC bus and a control coil with a winding that has a configuration to generate a magnetic field with flux that varies the reactance of the stator winding with the application of control coil current; a position sensing system for generating a rotor position signal that is representative of the angular position of the PM rotor; a control coil current sensor for generating a control coil current signal that is representative of the level of electrical current in the control coil; an electrical current sensor for generating a DC bus current signal that is representative of the level of DC current through the DC bus; an electrical potential sensor for generating a DC bus potential signal that is representative of the level of DC potential on the DC bus; a fixed pattern active rectifier and inverter system coupled between the AC bus and a DC bus; and a control coil current regulator system that regulates the control coil current; wherein the control coil current regulator system receives the DC bus current signal in a DC bus current feedback loop and the control coil current signal in a control coil current feedback loop to generate a corresponding level of the control coil current that regulates current in the stator to a desired level and in a generating mode the fixed pattern active rectifier and inverter system receives the DC bus potential signal in a DC bus potential feedback loop and the rotor position signal in a rotor position feedback loop to maintain a constant potential on the DC bus regardless of sudden changes in electrical load on the DC bus.