The demand on light weight in modern rail vehicles often contradicts the goal of high structural stiffness. Because of this, there is a need for development of new methods for reducing flexural vibrations without adding significant weight, in order to improve ride comfort. One method could involve attaching piezoelectric elements on the car body.
The attached piezoelectric elements convert mechanical energy from the structural vibrations into electrical energy, which is then dissipated in a shunt circuit. The piezoelectric elements are in this study shunted with two types of passive shunt circuits, one designed to damp a single structural vibration mode and another designed to damp two modes simultaneously.
Simulations, where the car body is modelled as an elastically supported simple beam, indicate that the method yields significant vibration suppression at the targeted modes with only a small amount of added weight. The simulations are supplemented by experiments on a 1:5 scale model of a Shinkansen 100 series vehicle.