Design and implementation of a decentralized controller for flotation process

Abstract

This research aims to design and implement a decentralized flotation process in real-time hardware in the loop scheme. The research objective is to supply sufficient literature on the flotation process and control development methods. To develop an open-loop and design controllers for the closed-loop model of the flotation process. The behaviour of the closed-loop system is investigated using the MATLAB/Simulink software environment. The investigation is based on the set point-tracking and disturbance suppression of the closed-loop system designed. The research is expected to identify the best performance between the decentralized and decoupling control methodology. The controllers are designed individually based on the developed transfer function of the flotation process. The first controller is a decentralized and decoupled PI controller. The second controller is a decentralized and decoupled Advanced controller. The advanced controller consists of a Model Reference Adaptive controller using the Massachusetts Institute of Technology (MIT) rule. The results of the relevant controllers are compared against each other by adjusting the manipulated variables, (air flow rate and wash water) and monitoring the Froth layer height and Gas holdup in the collection zone. These controllers are also subjected to disturbances that may occur in practice. The advanced controller modelled in the MATLAB/Simulink environment is translated to the Beckhoff Automation TwinCAT 3.1 environment for implementation on a Beckhoff PLC. The TwinCAT development environment is used for real-time simulation and analysis. The closed-loop hardware system behaviour is investigated under various process and disturbance conditions. The system simulation and hardware implementation results are to be compared. The PLC is then used for hardware in-loop implementation of the closed-loop system of the flotation process. The outcomes of the thesis are applicable to a flotation process implementing the proposed designed control strategy.