A new self-tuning robust PI controller for HVDC systems

Abstract

The design and implementation of a new self-tuning fuzzy-based robust controller for basic DC controls in an HVDC system is presented. The fuzzy logic approach uses rules based primarily on simple logical reasoning to adjust adaptively the controller gains and time constants of a single PI controller. Also, a fuzzy control-mode changer is implemented and applied for smooth transition from one control mode to another. Error signals and their derivative are input to the fuzzy system to give optimum system performance under various normal and abnormal conditions. Simulation results verify the improved performance of the proposed controller compared to the conventional PI controller under various operating conditions.