Rationalization Of Power System Architecture For More Electric Aircraft And Its Stability Analysis

With the fast development of the civil aviation industry,environment issue is becoming increasingly serious due to the rapid increase of fossil fuel combustion,aircraft emissions?such as CO₂,NO_x,etc.?and noise emissions.To overcome environment concerns,civil aviation is pushing ahead with More Electric Aircraft?MEA?technology.It is proposed to increase the use of electrical energy as it is proved to be more efficient than other kinds of energies such as pneumatic,hydraulic and mechanical energies that are commonly used in the aircraft.MEA technology is to saving energy by increasing aircraft efficiency and reducing maintenance requirements.While the improvement of the complexity and electrification of the on-board devices,it is required to optimize the aircraft electric power system architecture for saving costs about weight.In addition,the MEA power system stability would be compromised since more and more power electronics converters and motor drive systems,which normally behave as constant power loads,installed onboard MEA power system.In this paper,it is identified the best electric power system architecture for future MEAs based on the comparison and evaluation of both system weight and stability performance of the existing architectures.Then the optimization design of system parameters of MEA power system are proposed.The main efforts done in this paper include:?1?The typical four architecture of aircraft power system has been selected as the research object.First,the two candidates are choosing through weight saving analyses,stability performance for the initially selected candidates are further evaluated.Therefore,the most suitable architecture of power system can be obtained.?2?According to the selected best power system architecture,high-precision model is established including generators,power electronic converters and constant power loads.The influence of the interaction between subsystems on system stability is studied.The optimization of parameters is proposed by large-signal stability analysis.?3?The source,power conversion and type of load in the system are established,then the whole MEA power system model can be built by establishing high-precision reduced-order model of each component mentioned above.Based on the model,the influence of subsystem interaction in power system on the stability is studied.The optimal design criteria of system parameters is obtained by large-signal stability analysis.?4?A MEA high-precision nonlinear power system model is established,and the impact of its control parameters on system stability is further analyzed,then the optimal design of control parameters is proposed.To solve the influence of certain system parameter's performance constraint on power system stability,a stability compensation method is proposed in this paper.The virtual parameter is introduced to ensure the global stability of the system.?5?A simulation model of a 200kW MEA power system is established in Matlab/Simulink,all theoretical analyses are verified by simulations.