The FBD-method, a generally applicable tool for analyzing power relations

Starting from the most general case of m-wire unbalanced multiphase power systems with unsymmetrical loads under nonsinusoidal conditions, it is explained how the relations between currents, voltages and power quantities are analyzed in the time domain using the FBD method. Treatment in the frequency domain on the basis of Fourier series expansion of the time functions is also possible. It is shown that components of the total nonactive currents may be compensated without any time delay and without changing the collective instantaneous power. Rules are given for deriving simple equivalent circuits with m-equally structured branches from given voltages and currents