The presence of harmonic voltages and currents in the supply network cause many common power quality (PQ) problems.
There are three introductory Application Notes: Causes and Effects describes how harmonics are generated in the system, outlines the resulting problems and introduces the principles of the generic mitigation measures that are available. Interharmonics introduces the subject of non-integer harmonics which are becoming increasingly prevalent. Capacitors in Harmonic-rich Environments discusses the particular issues affecting capacitors.
The presence of harmonic frequencies can have an important influence on the accuracy of RMS measurements. The issues are discussed in True RMS Measurement.
Two important harmonic mitigation measures are discussed in Passive Filters and Active Harmonic Conditioners. Each of these Application Notes discusses the principles of operation and practical application.
Harmonic regulation can be a controversial and misunderstood issue. Understanding Harmonic Compatibility Levels explains the rationale behind regulation.
Harmonic currents cause additional losses that are not always fully taken into account by designers. Neutral Sizing in Harmonic-rich Environments discusses the process of selecting the proper size for neutral conductors in three-phase installations.
Selection and Rating of Transformers desribes the methods of selection and de-rating of transformers supplying harmonic loads. |
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