New Methods of Induction Motor Torque Regulation

Two methods of induction motor torque regulation are described utilizing speed and current feedback into the frequency and amplitude channels of a pulsewidth modulated inverter. Transfer characteristics illustrating the steady-state behavior of the two configurations are presented. Transient characteristics are discussed in detail by examining the linearized system transfer functions. An analytical approach to design of a closed loop controller for a practical application is outlined. Experimental results are presented showing correlation with predicted results.