Static and dynamic models of induction motors

The authors describe the modeling of squirrel cage induction motors and the derivation of steady-state and dynamic models that can be utilized in harmonic penetration studies. They present the results of laboratory testing of three-phase and single-phase induction motors to estimate these static and dynamic models. Such models are extremely useful in: identifying effective control strategies to enhance efficiency of variable voltage/variable frequency motor drives; assessing machine performance with excitation voltage and frequency variations; and identifying nonlinear load impedance models of induction motor loads in harmonic penetration programs such as Cyme and Harmflo software. These models were utilized in deriving efficient open-loop control strategies based on optimized volt/hertz (V_m/f_s) ratio characteristics for minimum input power, minimum losses, and maximum efficiency