2 results
Now showing1 - 2 of 2
- 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