抑制俯仰Ⅱ型PIO的四种滤波器性能比较

Performance comparison of four pre-filters used to prevent pitch categoryⅡPIO

FWB、DS、DASA、RLF作为4种成熟、有效的非线性滤波器均用于解决以作动器速率饱和为特征的Ⅱ型驾驶员诱发振荡(PIO)相位滞后的问题,从而抑制PIO发生.借助描述函数理论,对各滤波器中非线性环节线性化处理,得到4种滤波器拟线性传递函数和相频特性曲线,研究、比较各滤波器在不同参数、不同输入条件下开环相位补偿能力.针对俯仰PIO问题,选取本机动态特性较差、易发生PIO的纵向飞机模型,构建带速率限制作动器的人机闭环系统,通过3个典型的俯仰飞行仿真任务,从抑制作动器速率饱和能力、俯仰响应特性、相位补偿能力、减轻驾驶员操作负担4个方面全面比较各滤波器性能.实验表明:DASA滤波在抑制PIO、改善飞机俯仰响应特性方面相对较优.实验结果为滤波器设计、俯仰PIO抑制的相关研究提供有益参考.

Category II PIO cases are mostly characterized by actuator saturation. FWB, DS, DASA, RLF are four nonlinear pre-fihers that have already been used to compensate for the phase lag led by actuator saturation, thus to prevent pilot-induced oscillation （PIO）. Different means were used to make comparison among four pre-fihers. Dscribing function was used to analyze and compare the phase compensation in open loop analysis by linearizing the nonlinear components of the fourpre-filters. The study mainly focused on pitch attitude PIO, in a pilot-vehicle closed loop system with a neutrally stable pitch bare aircraft that could easily cause PIO, three typical pitch flight simulation tasks were used to make comparison in terms of actuator veloci- ty saturation prevention, pitch output dynamic characters, degree of phase compensation and alleviation of pilot operation burden, measured by pilot input magnitude. DASA turns out to be a better design among the four pre-fihers. The result can provide a useful reference for filter design and pitch attitude PIO prevention study.