A novel speed sensor-less vector control of Dual Stator Induction machine with space vector based advanced 9-zone hybrid PWM for grid connected wind energy generation system

Abstract

In this paper a novel speed sensor less vector control of Dual Stator Induction machine has been proposed for grid connected wind energy generation system. Dual Stator Induction machine consists of two stator winding separated by an electrical angle of 30°, with dissimilar pole to overcome the effect of harmonic current occurred in the stator windings. In this work the pole ratio of the two stator winding are taken as 3:1 in order to mitigate the magnetic saturation of the core and high losses which occurs at stator winding. The orientation of the machine is made in such a way that by controlling two stator currents in a perfectly decoupled way zero speed operation can be made possible. There by electrical frequency of it gets maintained at low speed, this characteristic of stator makes the Dual Stator Induction machine more suitable for speed sensor less operation. The two stator windings of the machine are fed from two independent Variable Voltage Variable Frequency inverter, which is being controlled by advanced bus clamping Pulse Width Modulation Technique. The Pulse Width Modulation proposed in this paper is a 9 zone hybrid PWM which results into lower line current ripple, reduced torque pulsation and minimized switch loss then the conventional space vector pulse width modulation, basic and advanced bus clamping PWM and the existing 3, 5 and 7 zone hybrid pulse width modulation. The simulation is being performed in MATLAB and the simulated results are being verified by experimental results. dSPACE DS-1104 Data Acquisition Card is being used to implement the overall control topology.