“…Sensor based speed estimators have the issues of high cost, complexity of installation, accommodating space, maintenance, intrusiveness, limited adaptability, delay in measurement, calibration, compatibility and environmental effect on sensor [ 4 , 14 , [60] , [61] , [62] , [63] , [64] ]. Using sensor based estimators especially in industrial applications such as steel rolling mill, ceramic and cement industries leads to the inaccurate results [ 25 , 65 , 66 ]. The development of research in speed estimation systems resulted in different techniques of sensorless based speed estimators for estimating the speed of induction motor drive systems.…”