Flux observation model of induction motor based on stator flux oriented vector control

Several kinds of methods in stator flux observation of induction motor are compared. As the DC offset and phase lag problem are caused by a pure integrator or a single-stage low-pass filter. The problem of voltage model of flux estimation is disturbed by variation of stator resistance particularly in the low-speed range. The current model is introduced to compensate the voltage model. It is suggested that a novel voltage-current flux observation model based on cascaded low-pass filter with programmable cut-off frequency and gain. The results of simulation and experiment validated the new model by a preferable flux estimation effect and robustness under variation of stator resistance in whole-speed range.