Phase-controlled frequency response measurement of a piezoelectric ring at high vibration amplitude

This article presents the measurement of the first-order frequency response function (FRF) for a piezoelectric ceramic ring at high vibration amplitudes. Due to the softening-type nonlinearity of piezoelectric materials, the maximum of the FRF is bended toward lower frequencies. Therefore, at high vibration amplitudes the vibration amplitude can become unstable, and this results in the occurrence of the jump phenomena. However, as we drive the piezoelectric ring by phase feedback control of the electric current, the vibration amplitude is stabilized and the whole FRF can be obtained. In addition to the frequency shift induced by the nonlinear behavior, there is an additional frequency change induced by the heat generated in the piezoelectric material. Both effects are investigated experimentally around the first radial mode of the piezoelectric ring. Moreover, the phase-controlled forced excitation driving method is presented, and its implementation is described in detail.