Expanders for dispersed power generation: maintenance and diagnostics problems

The article discusses the problems related to the operation of various types of expansion devices used in small cogeneration systems. Both volumetric and dynamic expanders were considered, including scroll, screw, vane, piston and turbine expanders. For each of these solutions, principles of operation were explained as well as major advantages and disadvantages. The results of experimental research on several expanders of various types were also presented. The overview of expanders included in this paper, along with basic operational problems and functional characteristics, is the collection of valuable information facilitating selection of a suitable expander for specific applications. This is particularly important in the context of search for new energy sources and opportunities to improve the energy efficiency of available energy resources.