航空发动机机载模型迭代计算优化方法研究

Research on Iterative Calculation and Optimization Methods of Aero-engine On-board Model

航空发动机是一个复杂、时变的多变量热力物理系统,其部件级模型的收敛精度与收敛速度对基于模型的发动机健康管理和容错控制等领域研究具有重要意义。现有的发动机部件级模型一般基于传统拟牛顿法进行各平衡方程的联立求解,较于传统牛顿-拉夫逊法(N-R法)收敛速度得到优化,但难以满足全包线范围内动态模型机载化应用的精度兼实时性要求。提出了一种自适应变步长因子拟牛顿法,可在保证模型计算精度的同时,最大程度地减少模型迭代次数,从而大幅提升模型计算速度,为模型的机载化应用创造条件。基于现役发动机计算平台MPC5554微控制器的仿真实验结果表明:相比于传统算法,所提算法具有更好的收敛性与实时性。

Aeroengine is a complex and time-varying multivariable thermophysical system. The research on the convergence accuracy and rate of the component-level model is of great significance to the modelbased engine health management, performance and fault-tolerant control. The existing engine componentlevel models are generally based on the traditional quasi-Newton method to solve the equilibrium equations simultaneously. Compared with the traditional Newton-Raphson method(N-R method), the convergence speed is optimized, but it is difficult to meet accuracy and real-time requirements of the dynamic model airborne applications within the full envelope. An adaptive variable step factor quasiNewton method is proposed, which can reduce the number of model iterations to the greatest extent while ensuring the calculation accuracy of the model, and greatly improve the calculation speed of the model and create conditions for the on-board application of the model. The simulation test results based on the current engine computing platform MPC5554 microcontroller show that, compared with the traditional algorithm, the proposed adaptive variable step factor quasi-Newton algorithm has better convergence and real-time performance.