ABSTRACT
This chapter describes the fundamentals of power calculations in AC circuits. We start defining the concept of impedance as an AC analog to resistance, but that depends on frequency when including storage elements (capacitors and inductors). Using impedance and its reciprocal (admittance) we generalize nodal and mesh analysis methods that are practical for complicated AC circuits and an excellent option when the circuits are very large, as it occurs in an electric power system. Subsequently, we define AC power, both its instantaneous and average calculations, and focus on complex power and the important notion of power factor and its correction. We finalize the chapter discussing DC to AC converters or inverters, which play an important role in modern electric power systems since some renewable power harvesters are DC, and there is a need to connect AC systems operating at different frequencies. The chapter provides a review of material typically contained in introductory circuit analysis textbooks [1-3] as well as electric power systems textbooks [4].
