Microprocessor based primary current control for cage induction motor drive

A novel approach for primary current vector control of a CSI-IM drive with an improved estimation of ωsl is described. Accurate digital control of the current vector orientation is achieved. Advanced software control logic provides the drive with rapid speed reversal and regenerative braking. Robust performance is achieved by use of a variable structure current controller. Large signal operation and optimization are briefly discussed. Experimental results verify the design.