Analysis and Optimization of a Double-Sided Air-Cored Tubular Generator

Abstract

Compared with the slotted tubular generators, air-cored tubular generator has no attraction force, smaller thrust ripple and lower moving mass. The advantages of high respond speed and high output stability make the air-cored tubular generators to be research focus in recent years. It is used in energy conversion systems of ambient vibrations, free-piston engine, ocean wave energy and so on. And in order to overcome the disadvantage of low power density caused by high equivalent air-gap, a tubular generator with double-sided permanent magnet (PM) arrays is proposed. The construction of the tubular generator topology is shown in Fig.1. The two sets of the corresponding Halbach PM array in the stators can help to increase the flux density in the air-gap to enhance the electromagnetic force and power density of the generator. In [1], an equivalent magnetic circuit model of the generator was established and basic characteristics were analyzed. In [2], the force characteristics of the generator with different phases were compared and the influence of the dimensions on the forces was analyzed.