Designingan Adaptive PID Controller for Dissolved Oxygen Control of the Activated Sludge Wastewater Treatment using Hedge Algebras

In this paper, we present the design methodology of the coefficients of adjustment of classical PI controller based on hedge algebras approach (HA - Hedge Algebras) to improve the quality of operation of the system. The adjustment works online with a wide range of adjustment enough around the value calculated by empirical methods Ziegler - Nichols. Subjects selected for trial is the controller method for dissolved oxygen in the wastewater treatment system by activated sludge method. Through system simulation in Matlab or Simulink environment at some different reference values, the results have been evaluated for quality control shows that the response time and overshoot reduce significantly, static deviation level is small. Through these results, it can be tested on the control system for more complex subjects to evaluate the effectiveness of methods and practical applications on the industrial control systems