The System Development of Electrically Heated Catalyst (EHC) for the LEV and EU-III Legislation

Future requirements of the legislative body in the USA and Europe, towards the reduction of exhaust emissions of motor vehicles, forces the automobile industry to improve its technology continually. An electrically heated catalyst, abbreviated EHC, offers a very high potential for exhaust gas reduction in the cold start phase of the engine.

A team of German automobile manufacturers is therefore developing a complete EHC System and laying down specifications which will enable the supply industry to undertake goal-orientated development of following components. The complete system comprises the components: heated catalyst, electricity supplier, electronic control, cables, plug and socket connections, secondary air system and their respective functions. In the following, the possible variations of the EHC system are explained and the components presented.