Magnetic Field Optimization of U-type Ironless Permanent Magnet Linear Motor Using Magnetic Permeable Block

U-type ironless permanent magnet linear motors (IL-PMLMs) are widely used in high-performance applications due to the advantages of high speed, acceleration, precision, and low wear. The magnetic field in the back iron of the traditional U-shaped IL-PMLMs appears a strong and weak alternating phenomenon. And the peak magnetic density is too high, which raises the risk of saturation. By employing a magnetic permeable block at the end of IL-PMLMs, the homogeneity of the back iron magnetic field can be optimized. Also, the design method of the best size of the magnetic permeable block is proposed. Finally, the optimization results of the magnetic field are verified by the finite element model.