Abstract: A diesel engine comprises a plurality of cylinders (2), an inlet duct (4), an exhaust duct (6), a turbocharger (8, 10) and a supercharger (14), the turbocharger being of variable output type and including a turbine (8) in the exhaust duct (6) and a supercharger (14) being of variable output type and situated in the inlet duct (4) between the compressor wheel (10) and the cylinders and being electrically driven or mechanically driven by the engine. The engine also includes a first sensor (25) arranged to produce a signal indicative of the speed of the engine, a second sensor (27) arranged to produce a signal indicative of the load to which the engine is subjected and a third sensor (26) arranged to produce a signal indicative of the pressure in the inlet duct (4) downstream of the supercharger (14). The sensors (25, 27, 26) are connected to a controller (29) which is also connected to the turbocharger and the supercharger and is arranged to vary their output independently.

Abstract: An in-cylinder pressure sensor obtains a high resolution pressure curve for each cylinder cycle allowing the various data to be derived for improved monitoring and control of operation of the engine. A more accurate measure of work done by the engine is obtained allowing more accurate estimation of the vehicle torque and hence real torque control. In addition, engine losses can be more accurately calculated and the estimates corrected yet further by obtaining an accurate top dead centre position for the engine cylinders.

Abstract: An in-cylinder pressure sensor obtains a high resolution pressure curve for each cylinder cycle allowing the various data to be derived for improved monitoring and control of operation of the engine. A more accurate measure of work done by the engine is obtained allowing more accurate estimation of the vehicle torque and hence real torque control. In addition engine losses can be more accurately calculated and the estimates corrected yet further by obtaining an accurate top dead centre position for the engine cylinders.

Abstract: A diesel engine comprises one or more cylinders (2), an inlet duct (4), an exhaust duct (6), a first pressure boosting device (10) of variable output type situated in the inlet duct (4) and a second pressure boosting device (14) of variable output type situated in the inlet duct downstream of the first pressure boosting device (10). A selectively operable bypass duct (11) is connected to the inlet duct (4) at positions upstream and downstream of the second pressure boosting device (14). A selectively variable throttle valve (15) is situated in the inlet duct (4) at a position between the second pressure boosting device (14) and the upstream connection of the bypass duct (11) with the inlet duct (4). An exhaust gas recirculation (EGR) duct (20) is connected to the exhaust duct (6) and to the inlet duct (4) at a position between the throttle valve (15) and the second pressure boosting device (14).