Experimental Validation of a Model-Based Water Injection Combustion Control System for On-Board Application University of Bologna

Format:

Book

Conference/Event

Author/Creator:

Ranuzzi, Francesco, author.

Contributor:

Brusa, Alessandro

Cavina, Nicolo

De Cesare, Matteo

Scocozza, Guido

Conference Name:

14th International Conference on Engines & Vehicles (2019-09-15 : Capri, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2019

Summary:

Water Injection (WI) has become a key technology for increasing combustion efficiency in modern GDI turbocharged engines. In fact, the addition of water mitigates significantly the occurrence of knock, reduces exhaust gas temperatures, and opens the possibility to reach optimum heat release phasing even at high load.This work presents the latest development of a model-based WI controller, and its experimental validation on a GDI TC engine. The controller is based on a novel approach that involves an analytic combustion model to define the spark advance (SA) required to reach a combustion phase target, considering injected water mass effects. The calibration and experimental validation of the proposed controller is shown in detail in the paper. At first, the focus is on the open-loop branch, to evaluate the performance of the combustion model and its ability to manage Spark Advance (SA) taking in account the phasing implications of WI, maintaining a pre-defined combustion phase target. Then the closed-loop (CL) chain is introduced, defining a structure that allows reaching the target while keeping knock intensity (KI) levels under an established threshold using two different control levers (SA and WI). At the same time, the controller has been designed to minimize water consumption. The proposed controller has then been implemented in a Rapid Control Prototyping environment, to validate the strategy on a real engine. As shown in the paper, this approach allows to manage both combustion phasing and knock level in an engine equipped with WI.The closed-loop controller was initially based on in-cylinder pressure signals both for knock intensity and combustion phasing measurements. To allow the proposed controller to be ready for an on-board implementation, there is the need to replace the pressure signal used from the in-cylinder pressure sensor, not available on commercial vehicles. For this, a specific signal processing algorithm has been developed to extract the angular combustion phase from the accelerometric signals available on-board, and it has been validated with experimental data

Notes:

Vendor supplied data

Publisher Number:

2019-24-0015

Access Restriction:

Restricted for use by site license