ABSTRACT
This research proposes a simplified approach to the modelling of quadruple tank system via the use of bond graph technique. The novelty of this approach is that quadruple tank system equations are easier to obtain. In addition, the process of obtaining the system equations is less prone to error because of the use of the pictorial advantage of bond graph. This is an advantage for complex systems such as Multi Input Multi Output (MIMO) systems. The 20-SIM software (bond graph technique software) was used in this work. In order to address the inherent multivariable constraint issues of the quadruple tank system such as looping and coupling effects, while minimizing the cost of control, the quadruple tank system was partitioned into Single Input Single Output (SISO) systems. This established the basis for the implementation of the Decentralized Model Predictive Control (DMPC) for the quadruple tank system. Due to the numerical ill-conditioning of the system state equations, a Quadratic Programming (QP) based scheme with inequality constraints was adopted. This was implemented in the Control toolbox of MATLAB. The classical predictive control scheme, achieved control horizon of a numerical value of one, and prediction horizon has values between 1 and fifty with an average settling time of 0.8439 seconds. However, the QPDMPC schemes' control horizon (M 10) and prediction horizon (M ) accommodating increasing values (infinite horizon) with time while the settling time of 0.04 seconds was attained. Validation of the controllers was carried out relative to classical PID controller.