Damping coefficient detector for damped oscillation

Abstract

In this research, the damp coefficient detector of damped oscillation is designed by analog signal processing and also relies on the current conveyor, which is indicated. It consists of four parts: a peak detector, a logarithmic amplifier, a limiting circuit and a differentiator amplifier. The peak detector output voltage has achieved the DC voltage which decays exponentially with time. Then, it is converted by the logarithmic amplifier in order of the linearity decays of the voltage and is revealed as the negative slope. Since the magnitude voltage of the peak detector is decreased until it rapidly approaches to zero, the analysis will not be in accordance with the idealized case. Thus, the limiting circuit is connected in front of the differentiator amplifier. This circuit functions as a maximum detector between the logarithmic amplifier and one of constants. Finally, the differentiator amplifier is applied to determining the derivative of limiting circuit output voltage. While, the input voltage indicates the under damped oscillator which is acquired by the RLC circuit and is investigated by distinct conditions. Consequently, the output signal obtains a DC voltage signal which has direct proportion with a damped oscillation. In addition, the relation between the analysis and PSPICE simulation results is also consistent.