Harmonics - Power Quality and Active Filters

摘要

All buildings face a variety of power quality problems as a result of the quantity and sensitivity of the connected load. One such concern of particular interest to the designer/user is harmonic current generation and the mitigation of its effects. The issue of harmonic distortion within a Commercial building facility is vast and complex. Harmonic disturbances and harmonic phenomena in general are not easy to understand. The mathematical relationships between voltage & current are extremely complex & depend upon the various components in each installation (generators, transformers, PFC capacitors & distribution network), the type of loads & the frequency of Harmonics. Modification in the installation or the load may significantly change the interaction between the various elements. Controlling harmonic phenomena requires not only know-how and experience, but also specialised equipment and software (spectrum analysers, software to calculate distortion in cables, network simulation software, etc.). With this in mind, it is important to remember that there are no magic remedies or universal truths concerning harmonic disturbances. Each installation requires a specific solution and to find that solution, a methodical approach is necessary.