Load Current Control Model for a Gas Micro-Turbine in Isolated Operation

Micro-turbines operation like power generator in oil facilities or rural industries, which are far away from generation and distribution services, is one of the most important applications for this generation device. This work presents a load current control model, for a 30 kW gas micro-turbine, fueled with natural gas, operating in isolated mode. A brief description of the isolated operation issues is performed, standing out the differences with power grid connected operation. Each model element is explained, emphasizing in the necessary modifications characteristic of isolated operation. It is explained the methodology for obtaining the model parameters, using the Toolbox Ident for systems identification of MatLab. Three types of models were tested: ARX, ARMAX and Box-Jenkins. The minimal square estimator is used to get the transfer function parameters in z domain. These functions were transformed into the frequency domain of s variable using zero order holder. Each model block was validated independently, explaining the nature of each variable and the reason for the correspondent error. In the end of this paper it was developed an application in Simulink-MatLab, using all the parameters obtaining for analyzing the whole model performance. Result graphics are shown with the conclusions. Recommendations for future developments are commented in the end