Lyapunov Function based Nonlinear Control of EGR-VVT Dual Loop in IC Engines

This study presents a control Lyapunov function (CLF) based nonlinear control design method for the intake and exhaust manifold pressure tracking problem with three control input: throttle valve opening, Exhaust Gas Recirculation (EGR) and Variable Valve Timing (VVT). Firstly, the optimal set-points are designed by solving the stationary optimization problem of minimize the fuel consumption and meanwhile to satisfy the coefficient of variation of IMEP (Indicated Mean Effective Pressure) constraint. Secondly, the Recursive Least Square (RLS) algorithm and Polynomial Fitting Method (PTM) are adopted to obtain an optimal estimation for the model parameters. Finally, a CLF based nonlinear control design method is applied to ensure the fast pressure tracking performance, and meanwhile to guarantee the combustion stability. Finally, the model and controller has been tested in on a real gasoline engine, and the experiment results demonstrate the performance of the control- oriented models.