Identification of harmonic content and their origin in power networks

A method for identifying harmonic content and their origin in power networks is proposed. It is based on the use of Fourier series for identifying the amplitude and phase of the harmonic components of the signal. It uses the direction of flow of the harmonic real power to identify the direction of flow of the harmonic current and therefore establishes its origin. The direction of flow of the harmonic real power is identified by the phase angle between the harmonic voltage at a bus bar and the harmonic current flowing out of the bus bar. The method depends on the accurate identification of the period of the power frequency for the tested signal. The accuracy of the method is demonstrated using synthesized signals as well as simulated system cases using the EMTP.