Analytical methods for invertor-fed induction motors

Invertor voltage waveforms for variable-frequency inductionmotor drives are frequently of a discontinuous form. One approach to steady-state analysis is to approximate periodic waveforms by a truncated Fourier series. As a less restrictive alternative, suitable for those commonly occurring cases where the piece-wise continuous sections can be described either as constant or portions of sine waves, relatively simple matrix methods yielding `exact¿ solutions are developed. These provide solutions for waveforms of all winding currents and torque, both for steady state and certain transients such as voltage disturbance types. For illustration, some computed and experimental results are compared.