This paper describes a novel technique to control the air fraction in the intake of dual-loop exhaust gas recirculation (EGR) Diesel engines. This control strategy enables to efficiently regulate the air fraction while satisfying a desired EGR proportion (between low-pressure EGR and high-pressure EGR). Based on a modified physical model of the air fraction dynamics along the engine air-path, a linear parameter varying (LPV) linear quadratic regulator (LQR) control is designed to ensure the stability of the air fraction while minimizing a quadratic performance index. The controllability of the system, necessary for the LPV-LQR control design, is verified by defining a convex parameter set using a polytopic approach. The controller is evaluated under strong transient conditions using an engine model that has been experimentally validated as a reference.
LPV Control, Diesel Engines, LQR
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