Analysis of a Tubular Linear Permanent Magnet Oscillator With Auxiliary Teeth Configuration for Energy Conversion System

The tubular linear permanent magnet oscillator (TLPMO) has been widely used in the industrial field as an energy conversion machine. Detent force is an obvious drawback of TLPMO, and one of the efficient ways to minimize this phenomenon is by adding auxiliary teeth. In this article, a magnetic field reconstruction (MFRC) method is proposed to analyze the TLPMO comprehensively, in which the auxiliary-teeth, slot, and end effects are included. First, the subdomain conversion model is used to consider the end effects of the slotless magnetic field under no-load condition. Thereafter, the two-step Schwarz-Christoffel transformation method is launched to account for auxiliary-teeth and slot effects. Subsequently, the MFRC technology is performed to integrate the above-mentioned results, and the forces are obtained. Finally, the accuracy of the presented method is validated by comparing the results from the FEA model and experiment of the TLPMO prototype. The main contribution of this article is presenting a hybrid method that has a good tradeoff between the computation time and accuracy. The analytical results using the MFRC method closely agree with that of the FEA model, and it has less than 7% deviation compared with the experimental measurement. Hence, it can be regarded as an efficient tool in the initial design procedures of TLPMO.