What is Insulation Coordination Study?
Insulation Coordination Study is a comprehensive analysis conducted to ensure the reliable and safe operation of electrical power systems. It involves evaluating the insulation levels and coordination of various electrical equipment, such as transformers, circuit breakers, cables, and surge arresters, within the system. We aim to deliver an insulation coordination study that verifies the compatibility of your chosen equipment and guarantees its adherence to the necessary performance standards for overvoltages, switching surges, and lightning-induced overvoltages.
Shielding Failure of transmission lines
Our studies cover the following types of overvoltages:
Lightning Overvoltage (Fast Front Overvoltage): The amplitude and shape of the overvoltage impinging on your substation from the overhead line conductor, as well as the behavior of traveling waves within the substation, are important factors. Our studies consider the steepness of the overvoltage and the separation distance between surge arresters and protected equipment.
We analyze direct strokes on phase conductors, which occur when low-magnitude lightning strokes bypass overhead shield wires.
Back Flashover in Power Systems
We identify potential back flashovers in transmission lines during lightning events, where the insulator voltage rises beyond its limits due to a rise in tower potential.
Switching Overvoltage (Slow Front Overvoltage):
Our studies address switching overvoltages generated during circuit energization, reenergization, or breaker and disconnector switch operations. Restrike-free operation of GIS circuit breakers and shunt reactors helps limit the impact of switching surges.
Temporary Overvoltage (Power Frequency Overvoltage):
Faults, switching operations, resonance conditions, nonlinearities, or their combination can lead to temporary overvoltages. These overvoltages are characterized by factors such as amplitude, oscillation frequency, and total duration.
Very Fast Transients Overvoltage (VFTO): Within a GIS, very fast transient overvoltages occur whenever there is an instantaneous change in voltage. These changes can result from the opening or closing of a disconnector switch. Our studies focus on the main source of VFTO generation, which is DS switching.
At VB® Engineering, we have the expertise and knowledge to conduct insulation coordination studies tailored to your specific needs. Trust us to ensure the appropriate selection of equipment and the satisfaction of performance criteria.