Design of a Data-Driven Adaptive Control based on OFSP for Discrete Nonlinear Systems

This paper presents the design of a data-driven adaptive control system based on output feedback strictly passive (OFSP) with a feedforward input for nonlinear systems in discrete-time domain. It is well recognized that an adaptive control system based on OFSP conditions can achieve asymptotic stability via a static output feedback. However, these conditions are very restrictive on most realistic systems. Therefore, a parallel feedforward compensator (PFC) is introduced to alleviate such restrictions, but remains a steady state error which is removed by utilizing the feedforward input. Besides, the data-driven approach is one of effective control strategies for nonlinear systems in the process control, and the control parameters can be updated rapidly at each equilibrium point. However, there is no research work that had been done in terms of applying the data-driven approach in a adaptive control system based on OFSP. Therefore, once the robust stability of the adaptive control system based on OFSP can be guaranteed, the adaptive gains can be optimized by the data-driven approach such that the output performance is able to be improved. The proposed scheme is verified through an numerical example, the results of which demonstrate the effectiveness.