Design method of compound frequency robust controller for cluster flutter suppression of longitudinal flight model

Abstract

The invention provides a design method of a longitudinal flight model cluster flutter suppression combination frequency robust controller. The design method comprises the following steps: determining a model cluster formed by amplitude frequency and phase frequency characteristics in a full envelope directly under the condition of giving different heights and mach numbers by a sweep frequency flight test; determining an open loop cut-off frequency section directly according to the amplitude frequency characteristics in the flight envelope; determining a phase margin section corresponding to the cut-off frequency section directly according to the phase frequency characteristics in the flight envelope; determining the number of compensation links and the parameter value by adding a multistage tandem lag-lead compensation link controller and according to the phase margin index in the aircraft full envelope and a model recognition method of system recognition; verifying effects of the controllers under the condition of giving the decibel number of the amplitude margin index in the aircraft full envelope; and designing the low-altitude flight robust controller which meets the requirements on flutter suppression, low overshoot and stability from the concepts of the phase margin and amplitude margin.

Description

technical field [0001] The invention relates to a design method of an aircraft controller, in particular to a design method of a longitudinal flight model cluster flutter suppression composite frequency robust controller, which belongs to the categories of measurement and control technology and flight mechanics. Background technique [0002] The control of the take-off and landing process of the aircraft plays an important role in flight safety; due to the large change in flight speed during the take-off and landing process of the aircraft, even according to the longitudinal model, it will face strong nonlinear problems; on the other hand, the control rudder of the aircraft has saturation, dead zones, etc. Phenomenon; From the perspective of flight safety, when flying at ultra-low altitudes (such as aircraft takeoff / landing), the controller must ensure that the system has a certain stability margin, no overshoot and stability, which makes the design of ultra-low-altitude flig...

AI Technical Summary

Problems solved by technology

[0006] In order to overcome the fact that the existing method cannot design a stable low-altitude flight controller that meets the stability margin index in the full flight envelope and can suppress flutter when the model of the aircraft changes greatly in the full flight envelope Technical defect, the present invention provides a kind of longitudinal flight model cluster flutter suppression compound frequency robust controller design method, this method obtains the full-envelope curve directly through sweeping flight test under the condition of different heights and Mach numbers A model cluster composed of amplitude-frequency and phase-frequency characteristics; directly determine the open-loop cut-off frequency interval according to the amplitude-frequency characteristics within the flight envelope; directly determine the phase margin interval corresponding to the cut-off frequency interval according to the phase-frequency characteristics within the flight envelope ; determine the number of compensation links and parameter values ​​by adding a multi-stage series lag-lead compensation link controller and the phase margin index in the full envelope of the aircraft and the model identification method in system identification; Amplitude Margin Index Under the condition of given decibel number, the controller effect verification is carried out; starting from the concept of phase margin and amplitude margin, a low-altitude flight robust controller that can suppress flutter, have small overshoot, and be stable in line with the full flight envelope is designed

Images