Characterization of a High Torque Density Halbach Motor in UAV Application

As the low-altitude logistics economy continues to develop on a global scale, increasingly demands are placed on the flight range and operational stability of small aircraft. Traditional brushless outer rotor motors have notable advantages in terms of torque density and light weight in Unmanned Aerial Vehicles (UAV). To further increase torque density, permanent magnet synchronous motor (PMSM) based on the Halbach array is utilized. In this paper, an integrated magnetization method is proposed to improve the assembly process of the Halbach rotor. The simulation and experiment results show that the magnetization apparatus attains the current of 18kA and magnetic field of 1MA/m, thus is capable for magnetizing the Halbach array with ~MH magnet grade. The magnetized Halbach array is assembled into the motor to test its performance, compared with original brushless motors, the torque density is increased from 8.5Nm/kg to 8.79Nm/kg, providing a higher performance solution for the application in UAV.