Optimization of air–fuel ratio control of fuel-powered UAV engine using adaptive fuzzy-PID

Traditional control method of air–fuel ratio (AFR) of aero engine cannot meet the performance requirement of fuel-powered unmanned aerial vehicle (UAV), which may lead to efficiency reduction and emission increase. In order to improve the control accuracy, this paper proposes a new AFR control method based on fuzzy-PID. We analyze the control results under different working conditions by using adaptive fuzzy-PID. Through simulation and experimental studies, we can draw the conclusions as follows: compared with PID control method, firstly, AFR control error can be reduced by 80% in normal condition; secondly, the control error is reduced by 55% in rapid acceleration condition; in addition, the control error can be reduced by 71% in continuous disturbance condition; comparison results with existing Fuzzy-PID also show that the improved controller has advantage in terms of resisting rapid and continuous interferences; moreover, in practical application of fuzzy-PID control, the highest AFR errors are about 3%. In normal condition, the error is reduced from 5 to 1% compared with PID control, which demonstrates the effectiveness of the improved fuzzy-PID control model. This research can be a reference in the application of UAV aero engine control.