Part 1 SAQ 1Exercise sheetCurrent spec2:212 min

ENGR5001 Part 1 Self-Assessment Questions, Q1

Develop a linear time invariant model showing the relationship between the input voltage ViV_i and output voltage VoV_o for the RLC network below (inductor LL and resistor RR in series, output taken across the capacitor CC).

What assumptions have you made? Put the equation obtained into the standard form, indicating the steady state gain, damping ratio, natural frequency, forcing function and/or time constant.

RLC network: L and R in series from the input V_i, output V_o across C.
RLC network: L and R in series from the input V_i, output V_o across C.
Formulas you may need
  • Inductor VL=LdidtV_L = L\dfrac{di}{dt}; resistor VR=RiV_R = Ri; capacitor i=CdVCdti = C\dfrac{dV_C}{dt}; Kirchhoff's voltage law (learn this)
  • Generalised second order form d2xdt2+2ζωndxdt+ωn2x=Ku(t)\dfrac{d^2x}{dt^2} + 2\zeta\omega_n\dfrac{dx}{dt} + \omega_n^2 x = Ku(t), steady state gain K/ωn2K/\omega_n^2 (learn this)
  • Generalised first order form τdxdt+x=Ku(t)\tau\dfrac{dx}{dt} + x = Ku(t) (learn this)