Active Vibration Control of Helicopter Fuselage with Large Dynamic Modeling Errors

Active vibration control is an effective method for vibration control of a helicopter fuselage. However, when there are large dynamic modeling errors of a control system, the effectiveness of active vibration control may decrease, or even the control may diverge by using the existing harmonic control algorithms. Large modeling errors will result in inaccurate frequency response functions in the control system. In this paper, a new frequency response function updating-harmonic identification algorithm and its convergence condition have been proposed for effective active vibration control of a helicopter fuselage with large modeling errors through identifying the frequency response function of the control system in real time. In addition, to improve the accuracy of identifying frequency response function and further improve the effect of active vibration control, a dynamic harmonic control weight matrix algorithm is also proposed in this paper. The active vibration control simulations and experimental validation on a dynamically similar and geometrically scaled structure of a helicopter fuselage verify that the proposed algorithm in this paper can achieve faster speed of convergence and better effect of vibration control when there are large dynamic modeling errors over the existing harmonic control algorithms.