Distributed electric propulsion aircraft makes it possible for additional control authority by differential thrust,thus giving rise to the concept of powered yaw control.A powered yaw control scheme based on the nonlinear dynamic inversion was proposed.A nonlinear flight dynamic model was established for the distributed electric propulsion,which explicitly considered the effect of differential thrust.Subsequently,according to the time-scale separation principle,this model was divided into two subsystems for the fast and slow dynamics,respectively.An nonlinear dynamic inversion controller was designed for the slow dynamics for the powered control,while the computed roll,pitch,and yaw rate were sent to the fast dynamic sub-system as reference.The fast dynamics controller was also designed using nonlinear dynamic inversion,which realized the tracking of the desired roll,pitch,and yaw rate by adjusting the thrust of multiple electric propulsors.Considering the redundancy and fault-tolerance of distributed electric propulsion system,the powered yaw control strategy was extended to the redundancy and propulsor failure scenarios.Meanwhile,to overcome the effect of gust encounters and changes in motor parameters,the local thrust controller for each electric propulsor was designed in the framework of active disturbance rejection control.The numerical simulation results show that the strategy can achieve 90° powered yaw and resist gust encounter of 15 m/s.
关键词
全电飞机/分布式电推进/推力差动/飞行控制/非线性动态逆/自抗扰控制
Key words
all electric aircraft/distributed electric propulsion/differential thrust/flight control/nonlinear dynamic inversion/active disturbance rejection control