Parameters affecting harmonic propagation and distortion levels in nonlinear distribution systems

The proliferation of different nonlinear and electronically switched loads has the potential to greatly elevate the harmonic distortion levels on the electrical distribution systems. The effect of different system and load parameters on the harmonic distortion is investigated. The attenuation and diversity effects represent the main factors that affect the system pollution. The effect of changing the inductive source impedance X/R ratio, system loading levels, load combination and nonlinear load position on the overall system distortion and the three-phase four-wire system neutral current and neutral to earth voltage (NEV) is studied. The analysis uses the time domain approach and utilizes the Electromagnetic Transient Program (EMTP) to model the different harmonic producing devices.