ANALYSIS, DESIGN, AND CONTROL OF A NOVEL HALBACH-ARRAY-BASED TWO-PHASE MOTOR

Abstract

This thesis presents a new Halbach-array-based two-phase motor. The motor is based on a 2-pole, 10-segment Halbach cylinder that generates a uniform magnetic field inside. This uniform field simplifies the torque calculation and gives the basis of position detection based on Hall-effect sensors. This thesis gives a general analytical method to find the magnetic field intensity inside the Halbach cylinder. The analytical field solution is verified by a finite-element analysis (FEA) and experimental results from Hall-effect sensors. The two-phase armature can generate constant torque in the uniform magnetic field. With a transconductance amplifier, the maximum torque and speed generated by the motor with the current input of 4 A are 0.057 N∙m and 276 rpm, respectively. With the controller developed in the thesis, this motor offers a self-position sensing method by two-phase Hall-effect sensors connecting to an Arduino microcontroller with a 0.5° resolution. The motor has the capacity to track the commanded motion and speed with error less than 0.6°.