ENB205 Lecture Electrical and Computer Engineering
AC Circuit Analysis with Phasors
1. Convert sources in complex form.
2. Convert components (R,L,C) in complex form.
3. Carry out circuit analysis as if it were a DC circuit (but with complex numbers on)
4. Convert the complex solution back to time-domain expression.
Frequency response of a circuit is the changes in its behaviour with change in signal frequency. Frequency respones
are important in some applications such as communication and electric filters. Frequency Response of a circuit can
be represented as:
Transfer function (mathematical representation)
Bode plot (graphical representation)
It indicates the relationship between input
and output of a system, be it electrical or
mechanical. It is usually defined as the
ratio of output to input.
In mechanical systems, input/output
could be force, energy, heat etc.
In electrical systems, input/output are
usually voltage, current or power.
1 Week 5 Tuesday, 27 August 2013 ENB205 Lecture Electrical and Computer Engineering
Time-independent Transfer Function Time-dependent transfer function
e.g. Circuit with time-varying components
E.g. DC circuit with resistor network.
Frequency-dependent e.g. circuit with inductive components
It is more of our interests as the input of