Analytical and experimental study for electromagnetic analysis of axially magnetized tubular permanent magnet machine by using virtual magnetization method

Tubular permanent magnet machines (TPMMs) are increasingly being employed in industries ranging from transportation, manufacturing, and office automation to material processing, health care, and generation systems, because of their high force density, high bandwidth, virtually zero attraction force, and absence of end windings. The advantages of such a machine are good linearity, no requirement for rotary-to-linear counterparts, and the notable absence of mechanical gears and transmission systems, which results in higher dynamic performance and improved reliability. Further, axially magnetized TPMMs, such as that shown in Fig. 1(a), have several attractive higher specific force capability than other magnet arrays, and they are easily magnetized by placing them in a solenoid impulse magnetizing fixture.