ANALYSIS OF FREE-PISTON STIRLING ENGINE LINEAR ALTERNATOR SYSTEMS .1.THEORY/

Linear alternators are frequently proposed and used as electric-energy -producing devices in connection,vith free-piston Stirling engines. Ho wever, while considerable research work has been done on this type of engine and on its dynamics and thermodynamics, there are only few stud ies dealing with the linear alternator and its interaction with both t he engine and the load. The objective of this article is to provide a mathematical model able to describe a free-piston Stirling engine/line ar alternator combination as a whole system, where the electric, dynam ic, and thermodynamic aspects are linked together. The engine/alternat or system drives through a tuning capacitor a static Load, In particul ar the method is applied 1) to calculate the force resisting the pisto n motion produced by the alternator and the associated load and 2) to derive a criterion of electric, dynamic, and thermodynamic steady-stat e operation of the machine.