Study on a New High Frequency Moving Coil Permanent Magnet Linear Motor

简介

In order to improve the characteristics of a conventional moving coil permanent magnet linear motor (MCPMLM), such as weak points on export force, response time, response speed, we studied a permanent magnet (PM) structure that is a key component of MCPMLM. Different magnetization techniques of single PM and different array structures of multiple PMs are compared, and a new MCPMLM magnetized along the external field force lines using eight pieces of a tegular Halbach magnet array with air gaps is proposed as well. The analysis on magnetic field and experimental results of MCPMLM demonstrates that the force between the coil and the PM increases by more than 40%. The simulation frequency is close to 350 Hz at -3 dB, and the response time is 0.005 s. In addition, the experiment frequency reaches 300 Hz at -3 dB and the response time is 0.004 s, which agrees well with the simulation results. It means that the developed MCPMLM enjoys advantages in high frequency and rapid response, and can satisfy the requirements of a high speed electro-hydraulic proportional valve.