Power line disturbances: a user´s perspective on the selection and application of mitigation equipment and techniques

The author examines the role of equipment specifications in avoiding power quality disturbances and the responsibility of the end user for providing an acceptable operation environment for the load. He describes the cause and effect of power line disturbances due to voltage variation, powerfail, transients, surges and sags, and harmonic distortion. He explains the categorization of disturbances as type I, II, or III, depending on their duration. He discusses mitigation equipment and techniques, namely, dedicated circuits, shielded isolation transformers, voltage regulators, transient suppressors, and uninterruptible power supplies. He briefly considers grounding requirements