Start-up method of micro turbine engine with closed-loop fuel flowrate control

The micro pressure difference method was used to measure fuel flowrate,which has the advantages of low pressure loss,high accuracy and fast response.A new orifice measuring section was designed,and a series of calibration experiments were done with different orifices.The experiments results show that the relation between flowrate and the square root of pressure difference was linear in the flowrate measuring range,which is in accordance with theoretical analysis.On the basis of the measuring method,a single neuron PID (proportion-integration-differentiation)controller was designed and used in the closed-loop control experiments of fuel flowrate.In contrast to open-looped control,this new control method is independent of pump characteristics,power voltage and outlet pressure.It also has good dynamic performance.In the end,the method was used in MTE(micro turbine engine) starting tests,which shows that it improves the quickness and reliability of start-up process dramatically.