Experiments toward chattering-alleviated discretized variable structure controller design of a brushless DC servo system

A novel sliding mode control scheme is presented in this paper. Among most sliding mode control schemes reported up to date, chatter is inevitable due to non-ideal switching control activity. Here, an implicit sliding mode control (ISMC) scheme, in which the switching hyperplane has been moved to the σ-space for chattering alleviation is presented. Experimental validation is performed by implementing the scheme on a high speed digital signal processor (DSP) to control a DC brushless servo system under varying inertia (ranging from 0.00006374 kgm² to 0.000338 kgm²). From experimental results, it can be seen that the proposed scheme shows significant robustness but with less chatter as compared to the conventional sliding mode controller design