Improving the Performance of a Small-Scale CHP Plant using Fuzzy Sliding Mode Controller

In order to cope with the problem of increasing fuel consumption and the greenhouse effect, efficient energy systems such as Combined Heat and Power (CHP) plants have been widely studied and used over past years. The strongly nonlinear behavior of the components of a CHP plant has led to the development of advanced controllers to ensure their safe and reliable operation. In this study, the Thermodynamic model of a small-scale CHP plant based on a recuperated micro gas turbine (MGT) was developed and governing equations of the system were obtained. Then, the system components were simulated by means of MATLAB Simulink. The aim of the paper is to design a Fuzzy - Sliding Mode (FSM) controller to control the speed of the turbine - compressor shaft and the turbine exhaust temperature simultaneously. The performance of the FSM controller was compared with the performance of a PID controller optimized using genetic algorithm (GA-PID) with two different input electrical load commands. The results show that the fuzzy - sliding mode controller improves the settling time in the shaft speed configuration at the desired value and maintains the exhaust gas temperature below the temperature limit.