Nonlinear Phenomena and Robust Stability for Discrete Control Systems

This paper analyzes the nonlinear phenomena and stability of discrete-time and discrete-value (discretized/ quantized) control systems. In this study, it is assumed that the discretization is executed on the input and output sides of a continuous nonlinear element, and the sampling period is chosen such that the absolute value of the backward difference of control signal does not exceed the resolution value. Based on the premise, the robust stability for nonlinear discrete (point-to-point) control systems is examined in a frequency domain. The relationship beween the sizes of sampling-period and resolution-value is clarified in numerical examples.