ACTIVE DISTURBANCE REJECTION CONTROL (ADRC) FOR A PILOT SCALE REVERSE OSMOSIS SYSTEM

摘要

Water scarceness has become a serious dispute in many countries now-a-days. So it is necessary for every individual to conserve water in their day to day domestic activities. Industries must be equipped with proper water treatment and recycling units with the intention of recycling water used by them. Thereby the recycled water should be meritoriously reused for other purposes. Industries like Dye and Pharmaceutical industries should be compulsorily equipped with waste water treatment plants, for example Reverse osmosis (RO) systems. Reverse osmosis systems plays a crucial chunk in wastewater treatment thus reducing the silt density index, hydroxyl ion concentration, etc. Generally reverse osmosis systems are used for providing ultra-fine purified water from saline water, waste water and also conduit water. Reverse osmosis systems bear a simple user-friendly setup and are easy to operate in all problems expository situations effectively. Hence it is clear that a pertinent control mechanism should be followed for the competent functioning of the process. This work focuses on the design and implementation of an Active disturbance rejection control system (ADRC) on an experimental RO membrane water system to address large set-point changes and variations in feed water. The transfer function of the system is to be formulated by suitable mathematical modelling of the reverse osmosis process and the outcome is corroborated with the System Identification toolbox available in MATLAB, with the help of real time observed values. This model then was used as the basis for the design of a nonlinear Active disturbance control system, using geometric control techniques.