Description SCR

In 2004 European countries introduced the Euro 4 vehicle emission standard and in 2009 they upgraded these requirements to Euro 5    These standards were designed to reduce vehicle pollution and atmospheric emissions.

To meet these standards the vehicle manufacturers were typically forced to adopt one or both of the following technologies to reduce the vehicle emissions of NOX

a) EGR – Exhaust Gas Recirculation System

b) SCR – Selective Catalytic Reduction

EGR System

This system typically works by reducing combustion temperatures which in turn reduces NOX output.

However for this system to work effectively the vehicle must use good quality low sulfur fuel but in many markets this low sulfur fuel is simply not available.  Using this poorer quality fuel often leads to engine problems and can cause premature and major  failure of the engine and components.

The vehicle manufacturers can be reluctant to cover these failures with their warranty because the vehicle was not originally designed for this high sulfur and poor quality fuel.  Consequently they often blame the driver for using fuel of an incorrect specification to lower their warranty costs.

 

SCR system

The common alternative to the EGR system is the SCR system.

This system relies on the addition of an additive injected into the exhaust stream to lower the vehicle emissions.

This additive is most commonly known by the name Adblue. In Europe it is available at many fuel filling stations either in containers or special dispensing pumps.   In addition to the normal fuel tank vehicles equipped with this technology also have a special Adblue tank.  The size of this additional tank is generally proportional to the size of the main fuel tank as Adblueconsumption is typically 4% to 8% of the fuel consumption.

The Adblue injection rate is constantly changing and is controlled by the vehicle electronics. The amount of Adblue injected is based on many different parameters.  these include engine speed, engine load, engine temperature, exhaust gas temperature and exhaust catalyst temperatures.

The additional injection of this Adblue increases the running cost of the vehicle making it unpopular with the vehicle operators.  This mandatory use of adblue  fluid on  these vehicles gives the vehicle operators major problems should ablue not be available in their location or if the adblue system develops a fault.  If the vehicle detects a problem with the Adblue system or if the adblue fluid is not used then the vehicle automatically enters a special reduced power mode.  This reduced power mode remains until either the ablue system is repaired or the adblue system is refilled.

We have developed our SCR emulation system to allow these vehicles to be operated in full power mode without the additional injection of the Adblue fluid.

This use of our SCR emulator lower the vehicle running costs, improves fuel consumption and greatly reduces or eliminates the repairs costs often associated with the adblue system.

Our SCR emulator receives many different messages and data streams from the vehicle high speed CAN communication message bus.  It then carries out complex mathematical  modeling and then broadcasts these modified messages and data back to the vehicle.   In this way the vehicle is fooled into thinking it is communicating with a fully operational Adblue system when in actual fact the Adblue system is not working and has been disabled.

The SCR emulator can be used to ensure the vehicle remains in full power fault free operating mode without using Adblue or when the original Adblue system is faulty.