Aeroengine on-board adaptive model based on improved hybrid Kalman filter

A method of establishing aeroengine on-board adaptive model was proposed based on improved hybrid Kalman filter (IHKF). The output of nonlinear on-board engine model (NOBEM) was regarded as the steady-state basic model of piecewise linear Kalman filter(PWKF), while its performance deterioration factor was regarded as the augmented state vector of PWKF for on-line estimation, and fed back to NOBEM for on-line updating. In addition, the switching logic of work mode was established, which could make the IHKF work better. By applying this method to a turbofan engine, a series of simulation results show that the model can always match the actual engine in the whole flight envelope, under different engine states and severe performance deterioration, thus meeting the needs of practical applications.