A nonlinear integrated model-based control design and analyses of an automobile powertrain using an infinitely variable transmission.

摘要

Emerging technologies and increasingly demanding performance requirements on automobile powertrains has rekindled research interest for the application of continuously variable transmissions (CVT). Research on sophisticated combustion engine controls, hybrid vehicles, and even otherwise entirely conventional powertrains are demonstrating significantly practical solutions for employing the CVT, even in the infinitely variable transmission (IVT) configuration. Various decentralized controllers have been shown in the literature to meet design objectives despite difficulties such as a seemingly inherent nonlinear nonminimum phase structure introduced by the transmission ratio changing continuously. The current investigation reveals that an integrated multiple input-multiple output (MIMO) model does not necessarily have the nonminimum phase structure. Further, the problem formulation is conducive to performance analysis, and the resulting system realization has desirable control properties.; The model is derived from rigid body dynamics, exemplifying a conventional spark-ignition internal combustion engine (SI-ICE) with a toroidal-tractive CVT configured as an IVT. Close-loop robust reference tracking is then demonstrated by a simulation of the system controlled by a model-based algorithm derived by merging the continuous gain scheduling approach with the output regulation approach.; Gain scheduling is popular in commercial industries because large ranges of diverse operations can be achieved even for system structures that cannot be handled by any standard techniques. Output regulation is unpopular in commercial industries because partial differential equations must be solved regardless of the system nonlinearities when the system is MIMO. These two dichotomous control methodologies are shown to be symbiotic under auspicious circumstances such as those posed by the integrated IVT powertrain control problem. The performance requirements on, and the dynamical structure of, the rigid body model derived for the IVT powertrain naturally suits this combined approach to reap the beneficial properties warranted by both.