RL,RC N RLC SERIES/PARALLEL CIRCUITS

OBJECTIVES Compute the circuit impedance for combined series-parallel RC and RL circuits. Determine circuit voltages, currents, and average power in combined series-parallel circuits. Discuss some basic RC, RL & RLC circuit applications. Relate voltage in and voltage out to the concept of lead and lag networks.

COMBINED SERIES-PARALLEL To analyze combination circuits which have both series and parallel branches, apply the concepts learned for both series and parallel RC/RL circuits.

METHODOLOGY ZT = ZS + ZP Find the total series Z for each branch. Reduce the circuit. Find the total impedance (Zt). Solve for V, I, q, and P as required. ZT = ZS + ZP

Ex: CAPACITOR Find ZT, IT, VC2, P (Note: Vs = E) Z2

Ex: CAPACITOR (cont) P = EI cos (qT) = (10V)(461 mA) cos(-42.4o) P = 3.40 mW

Ex: INDUCTOR Find ZT, IL3, P (Note: Vs = E) Z2 Z3

Ex: INDUCTOR (cont) P = EI cos (qT) = (10V)(1.01 mA) cos(31.4o) P = 8.62 mW

TOOLS Note from the previous examples, all of our tools from DC work: Ohm’s Law Voltage Divider Current Divider Kirchoff’s Current Law Kirchoff’s Voltage Law They are the same – but we use COMPLEX NUMBERS.

RC APPLICATIONS RC Lag Network RC Filter Low Pass Filter RC Lead Network RC Filter High Pass Filter

RL APPLICATIONS RL Lead Network RL Lag Network RL FILTER Low Pass Filter High Pass Filter

RLC APPLICATIONS Band Pass Filter Coax Cable

Review Quiz Voltage LEADS/LAGS current in an inductor? Voltage LEADS/LAGS voltage in a capacitor? How are true power and reactive power related to apparent power? What is a lead network? lag network? What is the methodology for solving combination series-parallel circuits?