A Vibration Suppression Method of Wind Tunnel Strut Based on Time Delay Compensation

Abstract

The invention discloses a wind tunnel strut vibration restraining method based on time delay compensation belonging to the technical field of wind tunnel test, and particularly relates to a wind tunnel strut vibration restraining method based on time delay compensation. Modal test is carried out on a cantilever beam system of a strut wind tunnel model through a hammering method to get a frequency response function of the system. A state feedback gain matrix is calculated using an LQR algorithm, and all states of an estimation system using a Kalman filter are output according to observation. The phase difference between acceleration sensor and piezoelectric actuator excitation signals in vibration control is analyzed using Lissajous figures, a phase shift algorithm is programmed in a controller to compensate the time delay, and finally, active vibration control is realized. The method can eliminate the influence of time delay, and has high flexibility and a large adjustable angle range. The problem that model vibration affects the safety of the system due to time delay in the existing wind tunnel ground experiment is solved. The method is of high adjustability, and is suitable for actual measurement in wind tunnel ground experiment.

Description

technical field [0001] The invention belongs to the technical field of wind tunnel tests, and in particular relates to a method for suppressing vibration of wind tunnel struts based on time-delay compensation. Background technique [0002] The wind tunnel test is based on the principle of relativity of motion, fixing the model or object of the aircraft in the artificial environment on the ground, artificially creating airflow to simulate various complex flight states in the air, and obtaining experimental data. important part of production. [0003] In wind tunnel experiments, the wind tunnel model generally adopts the tail support method. The tail of the model is connected to the force measuring balance and the support rod, and the tail of the support rod is fixed on the machete. The wind tunnel model-balance-support rod system forms a typical cantilever beam structure. This kind of support method has little influence on the flow field around the model, but because the le...

AI Technical Summary

Problems solved by technology

The time lag of the acceleration sensor and the piezoelectric actuator excitation signal is obtained through the hammering method and Lissajous graph analysis, and the time lag compensation phase shift algorithm and the linear-quadratic-Gaussian control algorithm (linear-quadratic-Gaussian control, hereinafter referred to as The controller combined with LQG) solves the problem of system instability caused by phase lag in the signal transmission process to a certain extent, and can ensure the closed-loop stability of the system

Images