ABSTRACT
Voltage sags and momentary interruptions cause the most widespread power quality problems, several other power quality disturbances can damage equipment, overheat equipment, disrupt processes, cause data loss, and annoy and upset customers. This chapter explores several of these, including transients, harmonics, voltage flicker, and unbalance. Several instances of equipment failures have been reported on the higher-voltage systems, usually from switching a large capacitor bank. Grounding problems within a facility can lead to equipment failures or malfunctions. Several events can fail equipment during a fault/interruption, from the disturbance that caused a fault, the voltage sag during the fault, a voltage swell during the fault, or the inrush while the system is recovering. A fault or lightning strike on the utility side can elevate the potential of the electric-supply ground relative to the television cable ground. Transients are triggered from capacitor switching, from line energization, and from faults.
