The positioning control of an electro-hydraulic variable rotational speed pump-controlled system using adaptive fuzzy controller with self-tuning fuzzy sliding mode compensation

The electro-hydraulic variable rotational speed pump-controlled system (EHVRSPCS) performs specific characteristics on non-linearity and time-varying. An exact model-based controller is difficult to be realized. In this study, the design method and experimental implementation of an adaptive fuzzy controller with on-line self-tuning fuzzy sliding-mode compensation (AFC-STFSMC) are proposed to deal with the system time-varying and non-linear uncertain behaviours by adjusting the control rule parameters. This control strategy employs the adaptive fuzzy approximation technique to design the equivalent controller of the conventional sliding-mode control (SMC). Furthermore, the fuzzy sliding-mode control scheme with self-tuning ability is introduced to compensate the approximation error of the equivalent controller for improving the control performance. The tuning algorithms are derived in the sense of the Lyapunov stability theorem; thus, the stability of the system can be guaranteed. The experimental results show that the AFC-STFSMC can perform excellent positioning control for the EHVRSPCS.