Aviation Turboshaft Engine Acceleration Optimization Control Study

In this paper, the mathematical model and control law of certain turbo shaft engine is researched. According to the causation of axis system torsion vibration that occured in the recent trial run after setting engine on helicopter, modified the model with adding the factual factors of transmission clearance, axis elastic torsion, and aerodynamic characteristic of aerovane to simulate the axis system torsion vibration. Then simulation is carried out to check the modification and look for the ways to restain the vibration. Based on the model, optimal control for turbo shaft engine acceleration is investigated with the method of Sequential Quadratic Programming(SQP) which is one of the most successful methods for solving nonlinear constrained problem.In the process of optimal control, most of performance constrains and component constraints which are present in the actual engine acceleration are considered. In order to exploit the powerful mathematic function of Matlab, the optimal control arithmetic was compiled on the Matlab platform. And the data alternation between control subprogramme and main routine was achieved through the interface of Matlab and Fortran.The results of simulation show that the modification is in accord with the practical situation of axis system torsion vibration, and the vibration could be eliminated by adjusting the PID parameter. It is proved that the optimal control law is feasible, which shortens the acceleration time, improves the dynamic performance compared with the traditional PID control principle. And the SQP control law has the characteristic of restraining axis system torsion vibration...