A Design Method for Stabilizing Modified Smith Predictors for Multiple-Input/Multiple-Output Time-Delay Plants

Abstract

The modified Smith predictor is well known as an effective time-delay compensator for a plant with large time-delays, and several papers on the modified Smith predictor have been published. The parameterization of all stabilizing modified Smith predictors for single-input/single-output time-delay plants is obtained by Yamada et al. However, they do not examine the parameterization of all stabilizing modified Smith predictors for multiple-input/multiple-output time-delay plants. The purpose of this paper is to expand the result by Yamada et al. and to propose the parameterization of all stabilizing modified Smith predictors for multiple-input/multiple-output time-delay plants. Control characteristics of the control system using obtained parameterization of all stabilizing modified Smith predictors are also given. Finally, a numerical example is illustrated to show the effectiveness of proposed parameterization of all stabilizing modified Smith predictors.

A Design Method for Control System to Attenuate Periodic Input Disturbances Using Disturbance Observers for Time-Delay Plants

“…Design C(s) to stabilize the unity feedback control system in (48). Such controller C(s) can be designed using the parameterization of all stabilizing modified Smith predictors for multiple-input/multiple-output plants in [24]. According to [24], when G(s)e −sL is stable, the parameterization of all stabilizing modified Smith predictors C(s) for stable plants G(s)e −sL is written as…”

A Design Method for Two-Degree-of-Freedom Modified Smith Predictors for Multiple-Input/Multiple-Output Time-Delay Plants

“…In order to show that the effectiveness of the proposed method, we compare differences between the response of the one-degree-of-freedom control system in [29] and that of the two-degree-of-freedom control system. The response of the output y(t) written by Eq.55 of the one-degree-of-freedom control system in Fig.…”

“…Since the parameterization of all stabilizing modified Smith predictors for minimumphase time-delay plants was obtained, we could express previous studies of modified Smith predictors for minimum-phase time-delay plants in a uniform manner and could thus design modified Smith predictors for minimum-phase time-delay plants systematically. Yamada et al expanded the result in [27] and proposed the parameterization of all stabilizing modified Smith predictors for nonminimum-phase time-delay plants [28]. But, their method cannot specify the input-output characteristic and the feedback characteristic separately.…”

A Design Method for Modified Smith Predictors for Non-Minimum-Phase Time-Delay Plants with Multiple Feedback-Connected Time-Delays

“…According to [6,8,12,23,24], the modified Smith predictor ) (s C makes the transfer function from r to y have a finite number of poles.…”

“…From this viewpoint, Yamada and Matsushima clarified the parameterization of all stabilizing modified Smith predictors for minimum-phase time-delay plants [23]. Yamada et al expanded the result by [23] and clarified the parameterization of all stabilizing modified Smith predictors for non-minimum-phase time-delay plants [24]. However, the method in [23,24] cannot apply for time-delay plants with multiple feedback-connected time-delays such as plants with reflection of radio wave or complicated feed pipe.…”