Self-sensing synchronized switch damping based on zero-crossing detection with voltage decay compensation

Synchronized switch damping (SSD) techniques have been developed for structural vibration suppression in recent years. In SSD control, a self-sensing approach can invert the voltage on piezoelectric materials at displacement extrema without sensors or real-time controllers. However, tracing extrema from the voltage on piezoelectric materials has become challenging since the voltage generated by the vibration of controlled mode is minor compared with noises as the increase of damping performance. Furthermore, the voltage decay caused by the current leakage is dominant when the host structure vibrates at a low frequency. This paper proposes a self-sensing approach based on the zero-crossing detection technique with voltage decay compensation. The switching delay and voltage decay are considered in the electromechanical model of the SSD system. Accordingly, a band-limited proportional-differential circuit is implemented to offset the voltage decay and generate zero-crossings at displacement extrema simultaneously. Experiments show that the proposed method is still effective when the voltage decay in the SSD control is dominant.