Active Helicopter Vibration Control Method Based on Adaptive Harmonic Identification and Frequency Response Correction

Abstract

The invention discloses an active control method for helicopter vibration based on adaptive harmonic recognition frequency response correction. In order to solve problems such as the decline of control effect or even control divergence, an adaptive harmonic identification algorithm is proposed to correct the parameters of the frequency response function of the control system in real time according to the harmonic coefficient of the control error response signal, so as to realize the comparison of the helicopter modeling error. The purpose of actively controlling the vibration of the helicopter under severe conditions. This method has the advantages of high frequency response estimation accuracy, fast control convergence, small calculation amount and no need for additional excitation. It can achieve high efficiency, strong adaptability and fast convergence control effect when the modeling error is large.

Description

technical field [0001] The invention belongs to the technical field of helicopter vibration control. Background technique [0002] Active vibration control technology is widely used in the field of vibration control of helicopters to meet the strict requirements for low vibration levels of helicopters. The realization of the traditional active vibration control algorithm depends on the accurate acquisition of the parameters of the dynamic model of the active vibration control system of the helicopter. The dynamic model of the active vibration control system of the helicopter is usually established through dynamic tests or wind tunnel experiments offline, so there are inevitably modeling errors. At the same time, factors such as changes in the flight state of the helicopter, changes in the load mass and the center of gravity will also cause changes in the dynamic model of the control system. In addition, for the variable speed helicopter, the change of the rotor load freque...

AI Technical Summary

Problems solved by technology

However, the realization of this kind of algorithm often needs to introduce additional white noise excitation to realize the identification of the secondary channel, so it will reduce the control effect

In addition, the Adaptive Harmonic Steady State (AHSS) control algorithm based on high-order harmonic control can realize the frequency response identification of the control system in the frequency domain, but such algorithms rely on the discrete Fourier transform of the measured response data, and a sufficiently large time interval is required to ensure that the system response reaches a harmonic steady state

For the helicopter body structure with low damping and low natural frequency, the too long harmonic steady-state time interval of this type of control algorithm will lead to too long control convergence time, which cannot meet the high standard of helicopter vibration level requirements

At the same time, in order to realize the accurate identification of the frequency response function, this type of algorithm needs to continuously apply additional continuous excitation, which will also cause the control effect to decline

In addition, these algorithms usually need to perform matrix inversion or matrix eigenvalue calculation. When the number of system control inputs and measuring point responses is large, the calculation amount of the algorithm will be greatly increased.

Images