Novel speed estimation technique for vector-controlled switched reluctance motor drive

摘要

This article discusses the speed-sensorless vector-controlled SRM-drive. The use of position/speed sensors have few concerns related to it in terms of cost, reliability, and compactness, a few to mention. Therefore, it is necessary to have some estimation strategy which estimates the speed/position. Since the control of the machine is done in dq0-reference frame, so by utilising these dq0-variables a novel speed/position estimation technique i.e. 'P-n-MRAS (Net-input-Power-based Model-Reference-Adaptive-System) speed-estimator' is developed for the vector-controlled SRM-drive. The speed-estimator implemented is simple, no look-up table is required and no external circuitry is required for injection of the diagnostic signal. Also, the estimator is free from differentiator and integrator terms. The proposed speed-estimator is stable in all the four quadrants of operation which is proved by performing the stability analysis. The estimator is dependent on two machine parameters (stator-resistance and amplitude of AC-component of self-inductance). The estimator is made robust to changes in stator-resistance by estimating the resistance online by proposed V-0-MRAS resistance-estimator. The drive has been extensively simulated in MATLAB/SIMULINK and results are also verified experimentally through a dSPACE-1104-based laboratory prototype.