ABSTRACT
This chapter provides the reader with an introduction to the use of complex notation and the j operator, which provides us with a convenient way of representing the effect of phase shift due to reactive components. Complex notation allows us to represent electrical quantities that have both magnitude and direction (reader will already know that in other contexts we call these vectors). The Argand diagram provides a useful method of visualising complex quantities and allowing us to solve problems graphically. When dealing with parallel circuits it is much easier to work in terms of admittance (Y) rather than impedance (Z). Expressing impedances and admittances in complex form provides us with some useful ways of solving complex series/parallel networks. It is usually easier to work with admittances when solving parallel circuits and with impedances in the case of series circuits. SCILAB is able to manipulate complex numbers and uses %i to represent the j operator.
