Interval type-2 Fuzzy Logic Controller of heat exchanger systems

Heat exchanger systems are widely used in chemical plants. They are affected on load and disturbance of the process plant, change in operation condition and nonlinearity. In this paper, we design an interval type-2 Fuzzy Logic Controller (FLC) for stirred tank heat exchanger systems. It controls the coolant flow in order to result in the desired temperature of output fluid. The inputs of this interval type-2 FLC are temperature error and change of error, while its output variable is the change on control signal for regulating the flow of coolant using a valve. Based on simulation results, there are evidences that show the performance of interval type-2 FLC is better than type-1 FLC in the case of handling the uncertainty, disturbance or change in operation condition of stirred tank heat exchanger systems.