Nonlinear dynamic inversion for the powered yaw control of distributed electric propulsion aircraft
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.
all electric aircraftdistributed electric propulsiondifferential thrustflight controlnonlinear dynamic inversionactive disturbance rejection control