J4 ›› 2015, Vol. 42 ›› Issue (1): 180-186.doi: 10.3969/j.issn.1001-2400.2015.01.029

• Original Articles • Previous Articles     Next Articles

Proximate time-optimal control scheme for speed-constrained servo systems

CHENG Guoqing1;HU Jingao2   

  1. (1. Dept. of Logistics Management, Xiamen Univ. Tan Kah Kee College, Fujian  363105, China;
    2. College of Electrical Engineering and Automation, Fuzhou Univ., Fujian  350108, China)
  • Received:2013-08-28 Online:2015-02-20 Published:2015-04-14
  • Contact: CHENG Guoqing E-mail:cheng@xujc.com

Abstract:

A proximate time-optimal control (PTOC) scheme with mode switching is proposed for typical servo systems characterized by the double-integrator model, aiming to achieve fast and accurate position regulation under speed constraint. The PTOC law exerts the maximum control authority for acceleration and deceleration when the initial position error is large, and ensures a smooth transition to linear control when the error goes down to some specified value. To satisfy the speed constraint, a stage for speed regulation is inserted between the acceleration stage and the deceleration stage of the servo system, and a mode-switching logic is designed. A linear extended state observer is adopted to estimate the un-measured speed and the unknown disturbance, to be used for feedback and compensation, so as to remove the steady-state error. The control scheme is then applied to a permanent magnet synchronous motor (PMSM) position servo system. Experimental tests have been carried out using the TMS320F2812DSP and the results verify that the controlled system is capable of tracking a wide range of target positions with desirable performance in the presence of load disturbance and speed constraint.

Key words: servomechanism, motion control, optimal control, disturbance rejection, observer

CLC Number: 

  • TP273