An Innovative Control System for a 2/4 Stroke Switchable Engine

Document Number: 2007-01-1199

Date Published: April 2007

Author(s):
Andrea Baccile - Ricardo UK, Ltd.
Daniele Ceccarini - Ricardo UK, Ltd.
Ling Cheng - Ricardo UK, Ltd.
Alessandro Iacoponi - Ricardo UK, Ltd.
Tim Lake - Ricardo UK, Ltd.
Andrew Noble - Ricardo UK, Ltd.
John Stokes - Ricardo UK, Ltd.

Abstract:
The 2/4SIGHT engine concept is based on a novel design of combustion system, which makes use of an electric-hydraulic valvetrain and advanced control technologies, enabling automatically controlled dynamic switching of the engine between two- and four-stroke operations. This concept has the potential to improve fuel consumption by up to 30% compared to a conventional gasoline engine.

A 3-cylinder GDI engine with two-stage boosting system and electro-hydraulic valvetrain is the main application for this project, with 6-cylinder application being studied in simulation.

The design of a Control System poses several challenges due to the simultaneous introduction of several innovations such as advanced boost system, electro-hydraulic valvetrain system and two/four-stroke operating mode.

In order to develop and optimize the design of the control system, an integrated simulation environment has been developed. This includes the model of the engine operating either in 2- or 4-stroke mode, the model of the innovative boost system, the model of the electrohydraulic valvetrain system, and the whole control system.

The Engine Control Strategies have been structured into the modules "Operating Mode Supervision," "Operating Mode Transition Management," "Air Charge Control and Estimation for 2- and 4-stroke operations" and "Valve Lift Profile Management."

A dedicated Valve Control Unit (VCU) controls each hydraulic valve; therefore, each cylinder can be independently controlled in all the operating conditions (2 stroke, 4 stroke and transitions).

Communication between the Engine Management System and the VCUs is defined by a communication protocol designed and developed to allow fast, safe and reliable operations.

File Size: 417K
Product Status: In Stock

Included in: V116-3

See other papers presented at SAE World Congress & Exhibition, April 2007, Detroit, MI, USA, Session: Electronic Engine Controls (Part 3 of 6)

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