The effect of power converter on the design of a Linear Alternator for use with a Joule Cycle-Free Piston Engine

Abstract

This paper describes the effect of alternative power conversion techniques on the performance of a Linear Alternator driven by a Joule Cycle-Free Piston Engine for electrical power generation. The design of a tubular Longitudinal Flux machine with axial magnets is performed using 2-D axisymmetric FEA modelling with transient solver to extract the rated power for three power conversion scenarios: Resistive Loading, Grid Interface, and Unity Power Factor Controlled Converter. The design study is carried out for a specific engine operating force and velocity, taking into consideration geometrical constraints for a compact system. Results are presented and discussed emphasizing the effect of the power conversion method on the idealized resultant machine physical and performance parameters.

Recent progress on performance and control of linear engine generator

“…Jalal et al 106 from Newcastle University utilised a Soft Magnetic Composite (SMC) with high resistivity to build the stator core back. The windings were sandwiched between them to form a compact stator, as shown in Figure 9.…”

“…Figure 9. LG in Newcastle University: (a) schematic diagram, (b) stator module, and (c) prototype 106. …”

Performance of a tubular machine driven by an external‐combustion free‐piston engine

“…This paper discusses the design and modelling of a tubular linear generator developed to extract electrical power from an external combustion FPE operating on the Joule cycle. The authors have previously presented work on the development of the electrical machine [2], the effect of power converter on machine design [3], and the importance of end effects on engine performance [4]. A simplified representation of the electrical machine coupled to a full thermodynamic model is given in [5].…”