Realtime modeling of driveline dynamics as estimator for control of AMT-gearbox in heavy-duty road vehicle
Typ
Examensarbete på kandidatnivå
Program
Publicerad
2020
Författare
Hamilton, Andreas
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
With Automated Manual Transmissions(AMT), gearshifting is controlled through
algorithms controlling both engine and actuators inside the gearbox. The objective
is to optimise shift in terms of comfort, energy efficiency and to minimise the time
without propulsion. There is relatively low stiffness and high inertia in the driveline
of a truck which affects torques and speeds of shafts in the gearbox. Torque is
complicated and expensive to measure in production gearboxes. Therefore there is a
value in developing algorithms for estimation and prediction. The algorithms modeling
the drivetrain needs to be computationally efficient to be run in real time but
also include the first order of resonance for the complete driveline. It is shown that a
simplified mathematical model of differential equations can replicate the behaviour
of the driveline and predict torques and speeds of shafts. Efforts has been made to
reduce the number of states in order to reduce the computational load. Comparison
of model with data from a test truck shows that accuracy can be achieved for a simplified
model with the use of known physical properties for a specific vehicle. The
model is also tested with forward Euler iteration method to determine necessary
step size to produce a stable prediction.
Beskrivning
Ämne/nyckelord
AMT-gearbox, driveline control, real time, dynamic model, estimation, prediction