An electromechanical power transfer system that transfers power between a prime mover and a direct current (DC) electrical system, comprises: 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 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; a position sensing system for generating a rotor position signal that is representative of the angular position of the PM rotor; and a control coil current regulator system that regulates the control coil current.