Active vibration damping

The damping of undesired vibrations in mechanical structures by means of piezoelectric components can be carried out either actively or passively. These methods are characterized as follows:

Active vibration damping

• External power source and control electronics required
• Application of countermovements in the control loop

Passive vibration damping

• Energy conversion in the material itself
• The electrical energy generated by the structural vibrations (mechanical energy) in the piezo elements is converted into heat for example, by means of resistors

In active vibration damping a structure exhibiting undesirable, weakly damped natural resonances is equipped with special actuators and sensors connected in a servoloop. The controller is set up so that in the vicinity of the intrinsic frequencies, the actuator behaves like a high-viscosity damper.
If one integrates piezoelectric elements (also termed adaptive materials), e. g. actuators, in the form of piezoceramic plates or disks, into a structure, it can then be equipped with sensor and actuator functions. With suitable control algorithms, it can then adapt itself to the desired conditions.