Speed control of a single and two phase induction motors using the diametrical inversion

The diametrical inversion (DI) of the stator voltages has been used to control the rotor position of the three-phase-induction motor. In this paper the DI is applied on a single-phase induction motor drive to control its speed. The change of the speed error sign causes a DI. Each DI inverts the stator voltage phasor and its angular velocity. The main and the auxiliary windings are always connected and so the sign of the speed error determines the rotating field direction. The motor is fed by a rectifier associated with a three-phase inverter module. Two reference voltages are PWM modulated using a sigma-delta closed loop strategy. The global system was implemented by Matlab/Simulink software. The simulation and experimental results allow assume a good performance.