Adaptive modelinverse technology for nonminimum phase system
                                                            YANG Liangliang，WANG Fei，SHI Weimin
                   (Faculty of Mechanical Engineering and Automation, Zhejiang SciTech University, Hangzhou 310018, China)

Abstract: Aiming at the trajectory tracking control problem in nonminimum phase system, the feedforward controller design method, modelinverse technique and adaptive control of nonminimum phase system were studied based on the closedloop injection architecture of it. The nonminimum phase ignore (NPZIgnore), zerophaseerror tracking control (ZPETC) and zeroamplitudeerror tracking control (ZMETC) technology were used to design the system feedforward controller, and the effect was analyzed. Based on it, aiming at the nonminimum phase zero offset in the system, the forgetting factor least squares method was used to realize the feedforward controller’s selfadaptation, and the simulation and experiment were carried out. The results indicate that the feedforward controller designed with ZMETC technology can improve the tracking accuracy of the nonminimum phase system more effectively than the ZPETC technology and the NPZIgnore technology. The tracking error is reduced by 61.45% and 56.27%, respectively. The adaptive algorithm can realize adaptive control of system parameter changes and improve the antiinterference performance of the system.

Key words: non minimum phase system（NMPS); feedforward control; modelinverse technology; adaptive; least squares method; trajectory dynamic tracking