Sensorless Speed Control Of Interior PM Machine With Axial Flux Regulator

Sensorless speed control of permanent magnet synchronous motor is one of the mature research topics where by different control algorithms are used to estimate rotor position and speed of motor in order to replace position sensor installed on machine shaft.The knowledge of rotor position and speed as feedback is indispensable for accomplishing any type of machine control.This thesis aims to design and implement sensorless speed control scheme for Interior Permanent Magnet Machine with Axial Flux Regulator so as to address challenges caused by mechanical sensors installed on its shaft.In contrast to conventional interior permanent magnet synchronous motor,IPMAFR has a unique structure with an independent axial flux regulator that provides a shunted magnetic circuit to the primary radial stator for enhancing flux regulation capability.In this thesis,a novel Extended Kalman Filter(EKF)is developed for estimation of rotor position and speed of IPMAFR.The filter takes advantage of specific feature of IPMAFR(axial stator)to estimate its rotor speed with improved dynamic performance.Axial rotor parameters are incorporated in the estimation algorithm of the proposed EKF so as to enhance estimated rotor position and speed accuracy.The performance of the proposed EKF for medium speed operation is fairly compared with that of conventional EKF through simulation tests and found to exhibit improved overall performance of the IPMAR drive.Specific flux based and current based model reference adaptive systems for estimation of IPMAFR rotor position and speed are also designed.Detailed analysis and fair comparison of the two sensorless speed control drives for normal speed operation are presented.After conducting Matlab/Simulink simulation tests under different medium speeds,general performance of estimated speed by flux based MRAS is found to surpass that of current based MRAS as it exhibits reduced speed fluctuations.The simulation results for both novel EKF and flux based MRAS algorithms are experimentally verified in the laboratory with actual IPMAFR.The experimental results prove the suitability of novel EKF and flux based MRAS techniques to replace position sensor installed on IPMAFR shaft.