Parameters Estimation of a Linear Model for the Microjet Engine Starting Phase with Least Square Method

In this paper,modeling and simulation of cold start phase for a microjet engine is investigated using both air and electric start methods. Based on a model identification approach, the mathematical models are developed and evaluated with experimental results. For the first time in small gas turbine engines,obtained results show that, ARX linear structure and BJ linear structure are appropriate for electric and air start modeling respectively. Parameters estimation of the models are performed with least square method.These models are selected based on AIC criteria. In addition, a monitoring system is designedand developed in LABVIEW environment to save Input/output data. The simulation results are then compared with experimental data where a good agreement is observed. Consequently the proposed models can be used in future works for different purposes like controller design and optimization.