TORQUE RIPPLE MINIMIZATION FOR SPM AND IPM DRIVE USING FUZZY AND PI CONTROLLERS WITH AN ONLINE STATOR REFERENCE FLUX

The torque ripples are crucial to the drive's ability to operate dynamically well. The torque ripples cause speed fluctuations that impair the drive's performance. The performance of PMSM drives is deteriorated, especially at low speeds, by these torque pulsations, which fluctuate periodically with rotor position and manifest as speed ripples. Therefore, a drive's successful dynamic functioning depends on the torque's smooth change. Direct Torque Control (DTC)'s primary characteristic is its lack of accurate mathematical models. Even though DTC's decoupling feature allows it to manage torque and flux independently, it can be challenging to choose the precise voltage space vector, which leads to substantial torque and flux ripples. However, with the aid of an appropriate voltage space vector, it is crucial to maintain torque and flux within certain bounds. Three sets of DTC space vectors are used to investigate the drive's transient and steady state performance using the "Maximum Torque per unit Current/Ampere (MTPA)" operation. Instead of using stator flux linkage, the online stator reference flux is determined using the "A Maximum Torque per Ampere (MTPA)" approach, which uses quadrature stator flux, direct stator flux, and torque reference. The performance of the three control parameters is assessed in terms of flux ripple, torque ripple and transient responsiveness to step variations in torque and speed control instructions. Three sets of DTC space vectors are taken into consideration with MTPA operation for analytical purposes. By selecting the appropriate membership functions and rule base in a fuzzy logic controller (FLC), torque and flux ripples can be significantly reduced, resulting in an accurate voltage space vector with a smaller hysteresis band. An attempt has been made to simulate and analyse DTC on PMSMs with both SPM and IPM rotor configurations. The performance of IPM and SPM are compared using DTC Strategy, by simulation with MATLAB/Simulink Tools. This paper's goal is to use DTC-SVM to reduce torque ripples of a PMSM drive on both IPM and SPM rotor designs. A drive's dynamic performance can be examined offline with the use of simulation software, which lowers costs and time and enables real-time system design.