Optimal placement and active vibration control algorithm for smart piezoelectric blades

As complex thin-walled curved components, aircraft engine blades feature intricate structures and operate under harsh conditions. Blade vibrations can directly affect the operational stability of aircraft engines. For the research of next-generation aviation engine blades that utilize piezoelectric materials for active vibration suppression, this paper proposes an optimal placement scheme based on finite element analysis and a variable step-size adaptive filtering control algorithm, for optimal placement of piezoelectric elements and active vibration control of smart piezoelectric blades. Firstly, three optimization objective functions for the configuration of piezoelectric elements are presented. The position of the piezoelectric elements is optimized by performing modal and transient analyses on the blade's finite element model and employing an improved differential evolution algorithm. The superiority of the modal strain absolute value-based position optimization scheme is validated through feedforward proportional control simulations. Subsequently, a VSS-FxLMS algorithm that dynamically adjusts the step size based on the error signal amplitude is proposed, capable of balancing convergence speed with steady-state error. Finally, a smart piezoelectric blade is designed according to the optimal placement results, and a real-time active vibration control experimental platform is constructed. Real-time control experiments are conducted and comparatively analyzed for single-frequency and multi-frequency disturbances. The experimental results demonstrate that the proposed VSS-FxLMS algorithm achieves effective vibration suppression with a faster convergence rate.