Resonance in RLC Circuits: Determining Resonant Frequency and Bandwidth - Prof. Maria Alba, Lab Reports of Electrical Circuit Analysis

Download Resonance in RLC Circuits: Determining Resonant Frequency and Bandwidth - Prof. Maria Alba and more Lab Reports Electrical Circuit Analysis in PDF only on Docsity! TEET 3145 Circuit Analysis II Laboratory # 9 RLC Circuits Fall 2009 Georgia Southern University   Mechanical and Electrical Engineering Technology Page 1 of 2 Name: _______________________________ Resonance in RLC Circuits Objective. Study the phenomenon of resonance in RLC circuits. Determine the resonant frequency and bandwidth of the given circuit using a sinusoidal response. Introduction. A resonant circuit, also called a tuned circuit consists of a resistor, an inductor and a capacitor together with a voltage or current source. It is one of the most important circuits used in electronics. For example, a resonant circuit, in one of its many forms, allows us to select a desired radio or television signal from the vast number of signals that are around us at any time. A circuit is in resonance when the voltage and current at the input terminal are in phase and the input impedance of the circuit is purely resistive. Figure 1: Parallel Resonance Circuit Consider the Parallel RLC circuit of figure 1. The steady-state admittance offered by the circuit is: Resonance occurs when the voltage and current at the input terminals are in phase. This corresponds to a purely real admittance, so that the necessary condition is given by The resonant condition may be achieved by adjusting L, C, or ω. Keeping L and C constant, the resonant frequency ωo is given by: --------------- ( eq .1) Frequency Response is a plot of the magnitude of Output Voltage of a resonance circuit as function of frequency. The response starts at zero, reaches a maximum value in the vicinity of the natural resonant frequency, and then drops again to zero as ω becomes infinite. Figure 2 shows a typical frequency response.