Return to search

The assessment of waveform distortion in power systems : validation of methods based on single-point measurements / Duan Serfontein

The portion of energy converted by non-linear loads in the modern power system is
increasing due to the energy-efficiency and sophistication possible with power
electronics. Higher voltage and energy ratings are continuously forthcoming. These
devices draw non-linear currents resulting in voltage waveform distortion at the Point
of Common Coupling due to non-zero supply impedances between voltage source
and the PCC. With the increase in waveform distortion comes the demand for better
Quality of Supply management.
The verification and quantification of the origin of waveform distortion in a power
system is a continuous field of study and forms a critical part of the mitigation design.
Methods utilizing single-point measurements, usually taken at the Point of Common
Coupling, for the assessment of the harmonic distortion generated by loads are
continuously being published. It’s been proven by means of computer simulations
and laboratory experiments that in an interconnected network where multiple sources
of distortion exist that loads have the ability to exchange harmonic active power
between each other. This project investigates the latter statement by conducting
practical experiments to conclude that loads have the ability to exchange harmonic
active power and that multiple synchronized measurements should be taken to
assess the harmonic distortion due to a load.
Laboratory experiments are carried utilizing an acknowledged single point
measurement method. The results are compared to the direction of harmonic active
power obtained from utilizing multiple synchronized measurements. To further the
information obtained from the laboratory experiments, practical experiments were
conducted utilizing the same methods. The results obtained coincided with the
results of previously conducted experiments of which the results were published.
From the results obtained it was concluded that in an interconnected network where
multiple sources of distortion exist that loads have the ability to exchange harmonic
active power between each other. Furthermore it was proven that the single point
measurement method investigated presented inconsistent results. Ultimately it was
concluded that the reason for the inconsistency was due to the fact that loads have the ability to exchange harmonic active power and that the single point measurement
failed to acknowledge this. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2012

Identiferoai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:nwu/oai:dspace.nwu.ac.za:10394/8486
Date January 2011
CreatorsSerfontein, Duan
PublisherNorth-West University
Source SetsSouth African National ETD Portal
LanguageEnglish
Detected LanguageEnglish
TypeThesis

Page generated in 0.0019 seconds