The global mega trend to reduce the dependency on fossil fuels to bring down transportation related CO2 emissions has pushed the use of an increasing number of alternative fuels. These fuels include bio diesels produced from various ester origins, and fuels with ethanol content (E10+). As the regional strategies to overcome foreign oil dependency vary, modern world cars will need to be prepared for diverse fuel qualities. Continental, the international automotive supplier, is coordinating a consortium named IQ FUEL to develop a highly integrated micro sensor system that determines the actual fuel composition in the tank. This new Fuel Quality Sensor makes it possible to optimize the engine control strategy according to the current fuel quality in the tank. In addition the intelligent sensor can detect substances in the fuel, such as sulfur, the gasoline water content, additives, and other contaminants. By using this information, engine components and parts of the exhaust gas after treatment can be protected against possible influences on their operation and the emissions level.
A new approach to optimize engine management
Engine management systems face an increasing diversity of fuel qualities today. The resulting variations in combustion- and pollutant-relevant fuel properties mean that we have to determine what we inject in the combustion chamber. Otherwise variations will go unnoticed which would bring down fuel efficiency and cause overly high emissions. The new intelligent Fuel Quality Sensor will make it possible to tune the engine control strategy according to the actual fuel quality in the tank and to get the maximum out of the engine at minimum consumption”, explained Klaus Hau, Head of Continental's Sensor & Actuator business unit. By early 2012 Continental will be able to provide functional samples of the sensor micro system to customers.
Intelligent sensor determines fuel properties
The new sensor is an embedded device that uses a MOEMS component (Micro OptoElectroMechanical Sensor) to determine fuel composition by measuring light transmission in the infrared spectrum. This optical measuring principle can be used to detect many different fuel properties such as density, heat value, cetane and octane number, sulfur content classification, viscosity and others. A single type of sensor hardware covers both, diesel and gasoline engine applications. Sensor data are analyzed by embedded chemiometric models that predict the fuel content based on a single specific parameter. Once installed, the sensor micro system will monitor the fuel composition and provide this information to the engine controller. Newly developed software modules in the engine management system (EMS 3) will be able to adjust core parameters like injection (timing and quantity). “Whatever the individual OEMs requirement is, the intelligent Fuel Quality Sensor will provide a starting point for adapting engine management. By integrating the sensor module in a vehicle and enhancing the engine controller software it will become possible to compensate fuel quality variations, to optimize engine operation and to protect not only sub-systems such as the exhaust gas after-treatment but also the engine itself”, says Gerhard Böhm, Head of Continental’s Engine System business unit. “The fuel quality sensor will thus help to ensure constant engine operation despite increasingly unpredictable fuelling options.”
Continental has been delivering fuel sensing solutions for many years and has utilized its experience (e.g. with flex fuel sensors and cylinder pressure monitoring) to integrate the new Fuel Quality Sensor and to translate the system’s comprehensive capabilities into engine management benefits.