Static Characteristics of Novel Air-Cored Linear and Rotary Halbach Permanent Magnet Actuator

This paper investigates the static characteristics of a novel air-cored linear and rotary permanent magnet actuator (LRPMA) with a Halbach permanent magnet array. By the given magnetization distributions and boundary conditions in the cylindrical coordinate system, the magnetic field distributions of the actuator are analytically analyzed using the magnetic scalar potential and the modified BESSEL functions. A 3-D finite-element (FE) model is established to validate the correctness of the analytical results. Analytical linear electromagnetic force and rotary electromagnetic torque, respectively, are derived and verified using the FE method for the characterization and optimization design of the air-cored Halbach LRPMA.