4 results
Now showing1 - 4 of 4
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Linear parameter-varying control for air/fuel ratio in SI engines with parameter dependent time delayThis paper is concerned with the air/fuel ratio control of direct injected, spark ignition (SI) combustion engines. The air/fuel ratio is essential for torque generation together with emissions and requires therefore a precise regulation. The system dynamics are modeled for controller design as a first order linear parameter-varying (LPV) system plus parameter varying time delay where the time delay is approximated by a first order Padé function. The scheduling signals determined by the engine operating point are reduced to a single scheduling parameter. The functional dependence on the plant parameters stored in look-up tables is then approximated by rational functions of this scheduling parameter. For controller synthesis a mixed sensitivity design (four-block) is used with parameter dependent weighting to adjust the requirements to the varying plant dynamics. An LPV controller with guaranteed stability and induced L2-norm performance is then obtained by solving linear matrix inequalities (LMIs) on a prespecified grid. Simulation results are presented to validate the designed LPV controller. They show performance superior to that of a scheduled PID controller used in serial production cars.Publicationtype: Conference Paper62 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Identification of low-complexity LPV input-output models for control of a turbocharged combustion engineComplexity issues related to experimentally identified LPV models are addressed, in particular the trade-off between model accuracy and number of scheduling parameters. For this purpose, an existing identification algorithm for LPV input-output models is combined with a parameter reduction technique based on principal component analysis. The approach is illustrated with experimental results on control of a turbocharged combustion engine. A low-complexity LPV input-output model is identified and validated. After transforming this model into state-space form-taking dynamic dependence on scheduling parameters into account-an LPV gain-scheduling controller is designed and assessed in closed-loop simulation with a validated nonlinear model.Publicationtype: Book Part18 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , LPV controller synthesis for charge control of a car engine - A hybrid evolutionary algebraic approachThis paper presents the design of an LPV controller for the intake manifold of a spark ignition engine. A nonlinear model of the plant is - with slight simplifications - turned into an affine LPV models in the form of an LFT representation. Using a hybrid evolutionary-algebraic synthesis approach that combines LMI techniques based on K-S iteration with evolutionary search, a scheduled PID controller is designed. A systematic method for initializing the search is discussed, that generates a set of LTI controllers which is then approximated in a least squares sense by an LFT controller. Nonlinear simulation indicates that the scheduled PID controller achieves the performance requirements.Publicationtype: Conference Paper17 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Application of LPV gain scheduling to charge control of a SI engineThis paper presents an application of LPV control to an LFT model of the intake manifold of an SI engine. The gain scheduled LPV controller approach is motivated by the highly nonlinear nature of the system. A nonlinear model of the plant is derived and slightly simplified to construct an LPV model as LFT representation. Using a controller synthesis technique based on K-S iteration a controller is obtained and tested in nonlinear simulations.Publicationtype: Conference Paper14