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. 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 co-ordinate 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.