New approach to field orientation control of a CSI induction motor drive

An improved approach to the field orientation control of a CSI-IM drive is developed using a microprocessor based system. The primary current variables in the synchronous reference frame are acquired directly from the DC-link current and the phase angle of the stator current. Flux position estimation is performed by feedback of the primary currents. This substantially reduces the matrix coordinate transformations and simplifies the control strategy. An innovation in the positioning control of the stator current vector is provided by a binary gating pattern in combination with a real-time interrupt technique. A new control scheme, incorporating a nonlinear current controller, has been developed. The analysis and control scheme are verified by experimental results