Micro Gas Turbine Range Extender Performance Analysis Using Varying Intake Temperature

A micro gas turbine (MGT) can potentially be an alternative power source to the conventional internal combustion engine as a range extender in hybrid electric vehicles. The integration of the MGT into a hybrid vehicle needs a new approach for technical validation requirements compared to the testing of an internal combustion engine. Several attributes of the MGT are predicted to cause concerns for vehicle sub-system requirements such as high ambient temperature and start-stop behaviour. This paper describes the results from specially developed experimental techniques for testing the MGT in a typical automotive environment. A black box MGT was used in this study for performance investigation during hot and cold starts. The MGT was instrumented and fitted with automotive standard components to replicate typical vehicle operational conditions. The intake air temperature was varied between 10 and 24 °C. A significant reduction in the power output of the MGT was observed as the intake temperature was increased. The proposed case scenario caused a reduction in nitrogen oxide emissions in the range of 0.02−0.04 g/km because of the lower combustion temperature at high intake temperature. However, hydrocarbon and carbon monoxide emissions have not shown a noticeable reduction during the power output degradation. The experimental results have highlighted the potential issues of using the MGT at higher intake temperatures and suggest design change to take the effect of higher engine bay temperature into account.