An aid for teaching doubly fed synchronous machines based on the circle diagram

This paper discusses with the extension of the circle diagram to the doubly fed synchronous machine (DFSM). Beyond the slip, this graphical approach is characterized by two leading parameters: the rotor voltage root–mean–square value and the angle between the stator voltage phasor and the rotor voltage phasor referred to as the stator windings. The generalization of the torque line in the case of the DFSM has allowed the machine power flow analysis.