Design of permanent magnet motor/generator using Halbach magnetized structure for the flywheel energy storage system

Permanent magnet (PM) motor is widely applied in the flywheel energy storage system (FESS). Compareing the characteristic of Halbach magnetized structure to ordinary parallel magnetized structure including air-gap flux density, magnetic field distribution and air-gap flux. Through optimezing parameters, Halbach magnetized structure not only can get regular sine wave form magnetic field but also has the superiority of parallel magnetized in air-gap flux density, air-gap flux and fundmantal wave component. Using finite element method to analysis Halbach static magnetic, obtained the optimum parameters of the model motor. By transient magnetic analysis, phase current curve with the current limit block, the magnetization had been restrained effectively. Since the FESS applied the magnetic suspension, the damping factor of this system was so low. At that condition the speed of the FEA result was 17320rpm.