Identification of engine model set for electro-mechanical transmission

The model based control strategy plays a key role in the power coordinate control. The powers from the electrical and mechanical sources are deeply coupled, and the dynamics of the engine strongly affect the coordinate control. In this paper, sweep signals are used as excitation signals to obtain a frequency domain model set of a class of plants with uncertainties. After collecting data from identification test, the Chirp-z transform is adopted to calculate the discrete frequency spectra of input and output signals. Then, discrete frequency response is obtained. With little priori knowledge of the plant and the type of uncertainties, Laguerre orthogonal basis functions are chosen to construct the nominal frequency domain model. Furthermore, a model set of the plant is determined by using a genetic algorithm, which can depict model errors and some unknown uncertainties. The results are helpful for system analysis and controller design.