An instrument for engine torque estimation and misfire detection
Abstract
The design of an instrument for the estimation of indicated torque and the detection of misfires in spark ignition internal combustion engines are addressed. The relationship between crankshaft angle of rotation and time is exploited to derive models describing engine torque production and the engine rotating dynamics in the angular position domain. Based on these models, an algorithm is developed to estimate engine indicated torque and a method is introduced to detect engine misfire. The implementation of the algorithm is also considered and leads to the design of an instrument for the estimation of engine indicated torque and the detection of engine misfire. The instrument is composed of two parts: (1) the engine angular speed variation (EASV) signal demodulator, which uses an engine angular speed driven tracking filter to realize engine crankshaft angle domain data processing; and (2) a special purpose microprocessor to implement the algorithm and detect engine misfire. A discrete implementation of the EASV demodulator was built and used successfully at the Vehicular Electronics Laboratory at the University of Michigan. A version of the very large scale integration (VLSI) implementation and layout for the demodulator is also introduced. The special purpose microprocessor has its own hardware multiplier and hardware DFT unit for real time on-board misfire detection.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1991
- Bibcode:
- 1991PhDT........26D
- Keywords:
-
- Dynamic Characteristics;
- Estimating;
- Internal Combustion Engines;
- Propulsion System Performance;
- Rotating Bodies;
- Spark Ignition;
- Torque;
- Algorithms;
- Angular Velocity;
- Demodulators;
- Layouts;
- Microprocessors;
- Multipliers;
- Onboard Data Processing;
- Real Time Operation;
- Tracking Filters;
- Very Large Scale Integration;
- Instrumentation and Photography