Mobility is essential to modern life, and is a key driver for economic growth. At the same time, the world's ever-increasing traffic volumes are a major source of pollution, which poses a fundamental threat to our future.
The solution lies in emission-free transport, an aim that leading car manufacturers and developers around the globe are working towards intensively. Until that goal can be fully achieved, new electronic systems and technologies will be instrumental in reducing emissions from combustion engines.
TT Electronics is a recognised expert in this specialist field, where the impact that exhaust fumes, extremely high temperatures and other aggressive factors can have on surrounding components represents a significant challenge.
An example of these increasing demands can be found in the latest generation of high-power vehicles, where the combustion process generates ultra-high temperatures to keep emissions down. These temperatures can harm the engines’ expensive turbocharger systems, meaning that precise monitoring is required to ensure temperatures remain within acceptable bounds, and to limit the engine power, should the acceptable range be exceeded. Our state-of-the-art temperature sensors can monitor this. They transfer thermal data as electrical information which can be handled by engine control units (ECU). For the driver of the car, the impact is barely noticeable.
TT Electronics’ sensors excel in their ability to withstand a variety of corrosive gases and aggressive liquids, thanks to their extremely robust housing. This level of protection has traditionally come at the expense of inferior temperature measurement: enclosing the cells typically makes them slow to detect changes in temperature, when what we need for turbocharger applications is real-time information. This is where our long experience and sophisticated modular mechanics concepts come in. Combined with endlessly tried-and-tested technologies such as thermal resistive like PT-200 and others, our sensors are highly responsive and extremely resistant to harmful external factors. The variety of available technologies and our ability to design customised solutions have already proved a competitive advantage in many cases.
Further limitations on specific pollutants (soot particles, nitrous oxides, CO and CO2) have been introduced at regular intervals for on-road and off-road vehicles. Europe and the USA have played a pioneering role, and their regulations generally provide a model for other countries around the world.
The currently applicable emissions standards are EURO 6, EPA 13 (both on-road) and Tier4final (off-road). The limits defined by these standards are forcing vehicle and engine manufacturers to introduce sophisticated exhaust after-treatment systems, as well as modifying their engines. The most important adaptations are diesel oxidation catalysts (re-oxidation of unburned hydrocarbons), diesel particulate filters (retention of rust particles) and selective catalytic reduction (conversion of harmful nitrous oxides in nitrogen and water).
While this change has so far mostly affected diesel engines, some petrol engines – particularly those with direct fuel injection – will have most likely to be fitted with gasoline particulate filters from September 2018 at the latest, when the next stage of the emissions standard (EURO 6c) is due to come into force.
To implement these measures effectively, we will need extreme systems that are able to support control algorithms, so that initial process and end values can be measured and transmitted in a suitable form to the vehicles’ electronic control units (ECUs). Sensors for key indicators measure the relevant physical properties, converting them into electrical signals and then relaying them to the ECU.