Engine Speed Based Estimation of the Indicated Engine Torque
Independent thesis Basic level (professional degree)Student thesisAlternative title
Varvtalsbaserad estimering av indikerat motormoment (Swedish)
The aim of this master's thesis is to implement and evaluate a method for estimating the indicated engine torque. The method is developed by IAV GmbH, Fraunhofer-Institut and Audi AG. The determination of the indicated torque is based on high resolution engine speed measurements. The engine speed is measured with a hall sensor, which receives the signal from the transmitterwheel mounted on the crankshaft. A transmitterwheel compensation is done to compensate for the partition defects that arises in the production and thus enable a more precise calculation of the angular velocity. The crankshaft angle, angular velocity and angular acceleration are estimated and the helpvariable effective torque is calculated using these signals as input. Through a relationship between effective torque and the indicated pressure the indicated pressure is extracted from a map. The indicated torque is then calculated from the pressure.
The method is validated with data from an engine test bed. Because of the low obtainable sample rate at the test bed, 4MHz, quantisation errors arises at engine speeds over 1000 rpm. Therefore the model is validated for low engine speeds and the result is promising.
Place, publisher, year, edition, pages
Institutionen för systemteknik , 2005.
Technology, Indicated torque, indicated pressure, finite automaton, transmitterwheel error, engine speed estimation
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-2789ISRN: LITH-ISY-EX--05/3569--SEOAI: oai:DiVA.org:liu-2789DiVA: diva2:20131