Parameters matching requirements for diesel free piston linear alternator start-up

Abstract

It is important to identify the relationship between the starting requirements and the structure parameters of the diesel free piston linear alternator on the structural design stage. In this article, the forces applied on the moving part during the starting process are analyzed, and an oscillation model is established. The numerical simulation results of the oscillation model are presented, and the energy-transfer mechanism is analyzed. Then, the oscillation model is simplified by utilizing the energy balance theory. Expressions of the achieved starting frequency and required starting force are derived and the effects of different design variables on them are investigated. The results show that the achieved compression ratio is determined by the energy balance between the friction consumption and the energy supplied by the starting force. The starting frequency achieved and starting force required are associated with the cylinder bore, the moving mass, and effective stroke of the engine, which can be applied to the matching design and optimization of the prototype.