Estimation of rotor current based on mathematical model of wound-field synchronous motor self-excited by space harmonics

This paper describes estimation of the rotor winding current based on a mathematical model of a self-excited wound-field synchronous motor where the space harmonics power is utilized for the field magnetization instead of the permanent magnets. The operation principle of the proposed motor is explicated by a voltage equation on the synchronous rotating reference frame. Furthermore, the rotor winding current is compared between the FEM based simulation and the mathematical calculation. Consequently, it has been confirmed that both operation characteristics in the steady state agree very well and indicate similar tendency.