Control of diesel engines with electrically assisted turbocharging through an extended state observer based nonlinear MPC. (February 2019)

• Record Type: Journal Article
• Authors: Song, Kang; Upadhyay, Devesh; Xie, Hui
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 233:Number 2(2019:Feb.)
• Page Start: 378
• Page End: 395
• Publication Date: 2019-02
• Subjects: Electrically assisted turbochargers -- air path control -- VGT-EGR -- nonlinear model predictive control -- extended state observer -- active disturbance rejection control; Mechanical engineering -- Congresses; Transportation engineering -- Congresses; 629.2
• DOI: 10.1177/0954407017744145
• Languages: English
• ISSNs: 0954-4070

Abstract

A two-layer controller for a diesel engine equipped with an electrically assisted turbocharger is proposed. A previously identified control-oriented plant model is used for control design. A GT-SUITE based high fidelity engine model is used as the plant. The high-level controller is designed based on the active disturbance rejection control method and uses an extended state observer for added robustness. The high-level controller tracks the boost pressure and intake manifold oxygen concentration. The low-level controller seeks to deliver the desired compressor power through an optimal affine split between the exhaust turbine power and the electric power. The optimal power split is determined by an optimal vane position for the variable geometry turbine. The corresponding optimization problem is solved using a nonlinear model predictive control algorithm that is adapted for fast numerical solution. Controller validation is conducted on the GT-SUITE engine model over the FTP-75 cycle. Results confirm the effectiveness the proposed control design and also illustrate engine performance benefits of an assisted turbocharging system, in terms of transient response (~70% reduction in accumulated boost pressure tracking error) and fuel economy (~4.4% reduction in brake specific fuel consumption) relative to a conventionally boosted system.