The addition of two or more wave forms that are in phase, resulting in a combined wave with a higher peak amplitude than the individual waves. In electrical systems, this can occur with harmonic frequencies or reflected voltage surges, leading to dangerous voltage spikes that stress insulation. It is a critical factor when analyzing transient overvoltages and signal integrity in high-frequency circuits.
The reflected wave caused constructive interference at the motor terminals, doubling the voltage and puncturing the stator insulation.
Related terms
Harmonics
Voltage or current components at whole multiples of the supply frequency, produced mostly by nonlinear loads.
Swell
Short-lived rise in RMS voltage above normal, often seen on the healthy phases during an earth fault.
Overvoltage category
Class from I to IV ranking equipment by its position in an installation and the surges it must survive.