An adaptive negative capacitance shunt network for increasing performance and robustness in terms of noise and vibration attenuation

Abstract

Due to its broadband performance, the negative capacitance shunt can be used for damping multimode systems with varying eigenfrequencies. They are usually built with operational amplifiers and passive components. This setup is sufficient for laboratory tests, but in real applications, this rather simple setup cannot be used, due to a tradeoff between efficient damping and the risk of instability. Therefore an adaptive negative capacitance circuit is presented in this paper, which is developed for automatically tuning the capacitance ratio to the appropriate value. Tests at a beam structure show, that both better damping and the avoidance of saturation effects and instabilities are achieved.