Small Disturbance Stability Analysis Of Aircraft Power Supply System

Modern aircraft is developing in the direction of more electricity and all-electricity.As the core of more electric aircraft,the safe and stable operation of the aircraft power supply system is an important guarantee for the normal operation of the aircraft.Because of the multi-generator parallel connection,multi-converter cross-connection,electrical load The nature of the complex,its complex transient process often involves a large number of nonlinear phenomena,making the small disturbance stability analysis of aircraft power supply system has speciality and complexity.On-board secondary power supplies such as transformer rectifiers are the most common non-linear loads in aircraft power systems,and their operating modes and parameters have an important impact on the stability of the power supply system.The dq transformation method is used to transform the power supply circuit of the transformer rectifier,and the small disturbances stability of the equivalent circuit is analyzed.The sensitivity of the line parameters is calculated at the steady-state operating point,and the influence of different parameters on the small disturbance stability of the aircraft power supply system is analyzed.Finally,simulations using Simulink verify the correctness of sensitivity calculation.According to the analysis,the DC side voltage of the uncontrollable transformer rectifier will change with the parameters of the aircraft power supply system,and it will also have a bad influence on the small disturbance stability of the aircraft power supply system.Therefore,the power supply circuit of the PWM type controllable rectifier is adopted.The dq transform is performed,and the small disturbance stability analysis and sensitivity calculation are performed on the equivalent circuit.Finally,for the PI regulator in the PWM rectifier,the influence of the regulator parameters on the small disturbance stability of the aircraft power supply system is analyzed and verified by simulation.The calculation and analysis results also show that the transmission cable will have an impact on the stability of the aircraft power supply system.The specifics are as follows: With the reduction of equivalent inductance,equivalent resistance and DC side resistance,the stability of the aircraft power supply system will come.The worse,as the DC side inductance decreases,the stability of the aircraft power system will get better and better.The analysis results also show that the controller parameters also affect the stability of the aircraft power system.