Effect of Air Gap in Switched Reluctance Linear Motor Performance

Abstract

This paper discusses the effect of air gap on Switched Reluctance Linear Motor (SRLM). Linear motors with permanent magnet are among the best option for applications requiring high acceleration, high speed and high precision. However, permanent magnet usage such as Neodymium Iron Boron (NdFeB) has led to an increment of material cost due to the fluctuating price of rare earth material problems. The alternative solution is by using an electromagnet. To overcome the issue of SRLM on low thrust, the optimization of some important parameters will influence the inductance and magnetic flux. The thrust needs to be maintained for use in high precision applications. The study covered the air gap length, δ parameter which is 0.1mm,0.2mm and 0.3mm. In this design, Solidwork software is used to modeling the SRLM. The static characteristics of the SRLM are calculated using a finite element method analysis (FEM) and the performance of every model has been compared. The SRLM model with optimal performance according to the parameter configurations is when the air gap length is 0.1 mm,3 mm teeth pitch and 0.4 teeth ratio, where the thrust reaches 48 N. In conclusions, the thrust increase when the air gap decrease. Finally, the analysis presents in this paper can be used to determine the best SRLM structure based on the desired thrust with appropriate combination size of the parameter that has been exposed as a guideline to other researchers. It is recommended to study the functionality of the dynamic characteristics of SRLM by developed the motor drive system to enhance the performance of SRLM motor.