title: A novel condition for stable nonlinear sampled-data models using higher-order discretized approximations with zero dynamics.
abstract: Continuous-time systems are usually modelled by the form of ordinary differential equations arising from physical laws. However, the use of these models in practice and utilizing, analyzing or transmitting these data from such systems must first invariably be discretized. More importantly, for digital control of a continuous-time nonlinear system, a good sampled-data model is required. This paper investigates the new consistency condition which is weaker than the previous similar results presented. Moreover, given the stability of the high-order approximate model with stable zero dynamics, the novel condition presented stabilizes the exact sampled-data model of the nonlinear system for sufficiently small sampling periods. An insightful interpretation of the obtained results can be made in terms of the stable sampling zero dynamics, and the new consistency condition is surprisingly associated with the relative degree of the nonlinear continuous-time system. Our controller design, based on the higher-order approximate discretized model, extends the existing methods which mainly deal with the Euler approximation.
authors.affiliation: College of Science, Guizhou Institute of Technology, Guiyang Guizhou 550003, China; College of Computer Science and Technology, Guizhou University, Guiyang Guizhou 550025, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zeng
authors.affiliation: College of Automation, Chongqing University, Chongqing 400044, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Liang
authors.affiliation: College of Computer Science and Technology, Guizhou University, Guiyang Guizhou 550025, China.
authors.forename: Shuwen
authors.initials: S
authors.lastname: Xiang
keywords: Consistency condition; Controller design; Exact sampled-data plant; Higher-order approximation discretized model; Zero dynamics