Função de Transferência e Estabilidade

Prévia do material em texto

Step 1 of 3 11.025E Write the expression of open loop transfer function of a feedback amplifier. Determine the closed loop poles. Expand the term with cubic power. Take Now write the equation with this assumption. Therefore, the roots of the cubic equation are Step 2 of 3 The root locus of the feedback amplifier is shown in Figure 1. j@ a 0 Figure 1 Step 3 of 3 The amplifier becomes unstable when the complex poles lie on the imaginary axis, that is, when The real part of the complex roots should be zero. Equate the real part to zero. Therefore, the feedback factor at which the amplifier becomes unstable is 0.008