A study of translator length in a tubular linear electrical machine designed for use in alinear combustion joule engine

The aim of this paper is to investigate the integration of a tubular linear electrical machine with a linear free-piston combustion engine in order to create a single integrated free piston engine generator. The performance of the engine when coupled to a long and short translator electrical machine is discussed. To simulate the dynamic performance of the overall system, an integrated thermodynamic, mechanical and electromagnetic model is required. LMS Amesim software is used to model the thermodynamic engine and electromechanical finite element analysis is used for the electrical machine. The overall performance of an engine coupled to electrical machines with varying translator length is investigated. The performance of such a tubular generator is demonstrated by measurements on a 7-pole/6-slot prototype machine. The short translator generator design appears to perform better in terms of performance and capital cost, based on the dynamic simulation results of the system.