Operator based fault detection and compensation design of an unknown multivariable tank process

Abstract

In this paper, robust nonlinear tracking control design and operator based fault detection design employing robust right coprime factorization for an uncertain heat exchange tank process are proposed. To prevent unexpected temperature variation and accident of heating an empty tank, liquid level in tank must be controlled simultaneously with the liquid temperature, where control is Multi-Input Multi-Output (MIMO) control. Therefore, first, nonlinear models of liquid temperature process and liquid level system are obtained. This liquid level model is the system assumed the fault occurrence, meanwhile those models have uncertainties and coupling effects. Second, operator based nonlinear feedback tracking control system are realized by using robust right coprime factorization corresponding to the MIMO process. Third, operator based fault detection and compensation design is proposed, and this design is inserted into the control system. Moreover, tracking controllers are designed to obtain desired tracking performance. Finally, the effectiveness of the proposed models and methods is confirmed by simulations.