Numerical analysis of a brushless permanent magnet DC motor using coupled systems

Abstract

This thesis deals with the modeling, simulation and performance analysis of a brushless permanent magnet DC motor (BLDC) using numerical methods. The primary objective is to develop efficient and practical procedures based on numerical techniques to analyze the steady state and dynamic performances of the BLDC motor. Dynamic model of the BLDC motor is developed using circuit-field coupled time stepping FEM. An improved steady state model is proposed using time stepping FEM combined with magneto-static FEM to reduce the computational expense using time stepping FEM alone. To analyze the motor with a controller as an actual system, a new approach to couple the time stepping FEM with closed loop control structure is implemented. Using this new scheme, application characteristics of the HDD spindle motor is investigated. In order to determine the accuracy and validation of the numerical models, DSP based BLDC motor test stand is developed and tested.