Transient and steady‐state study of a speed sensorless IPMSM drive with an advanced integrator‐based stator flux estimator

Abstract

In this paper, an advanced integrator is proposed for the estimation of stator flux in a direct torque control (DTC) drive. A two-level lookup table-based direct torque-controlled interior permanent magnet synchronous motor (IPMSM) drive is implemented. DTC has the inherent disadvantage of DC drift and saturation in stator flux estimation due to a pure integrator. In the proposed work, a different approach to estimate stator flux is reported overcoming the constraints of a pure integrator in DTC. An advanced integrator with an adaptive controller is implemented to determine the stator flux and enrich the performance of the drive. A comparison of transient and steady-state analysis is carried out when IPMSM is fed by a low-pass filter-based DTC and proposed stator flux estimator-based DTC. To make the system mechanically robust, stator current-based model reference adaptive control is executed to estimate the motor speed. A mathematical derivation for the stability study of the adaptation mechanism is carried out using Popov's hyperstability criteria. The proposed algorithm is implemented in the MATLAB/Simulink environment and the soundness of the proposed work is presented by simulation results. Moreover, the experimental analysis using dSPACE1104 justifies the simulation results of the proposed system.