| A turbocharger is used to feed air into the engine in order to keep the air-fuel ratio at acceptable levels and optimize the combustion. The boost pressure is controlled by the main STT Emtec electronic control unit (ECU), operating a pulse width modulated valve. The ECU is also controlling the amount of exhaust gases to be re-circulated by the EGR valve.
The control system is depending on the engine load, speed and temperature. The exhaust gases are cooled by an EGR cooler to reduce the exhaust gas temperature before it is mixed with the inlet air. In addition an intercooler system is added to increase the density of the compressed inlet air.
A full technical description listing advantages of this system follows on pages 3, 4, 5 & 6. |
