Fortressing your power network
Improving reliability and availability of the utility’s transmission system
History shows that powerful emperors built and ruled their empires from unconquerable forts. Indeed the power of the ruler was directly proportional to the degree of invincibility of their fort. Apart from military operations, the impact of forts on political and administrative matters was also profound.
So what constituted an impregnable fort? Forts were built on the seemingly simple principle of multiple layers of defense. They were surrounded by deep moats – the first layer of protection – which made them inaccessible to invading enemies. The thick outer walls acted as the second line of protection and absorbed the firing. Bastions built at regular intervals allowed defensive fire in several directions and worked as the fort’s third ring of defense.
Utilities need protection in a similar manner to avoid interruption in power from high current surges entering the substation during lighting flashovers. This multiple layer-like protection for the utility could come from the transmission line towers if they are equipped with the right solution.
Selected towers along the transmission line are installed with Line Surge Arresters (LSA) parallel to the insulation. In case of a back flashover, part of the lightning in the affected tower will be shunted to the earth – the first layer of protection for the utility. The LSAs in the towers in the immediate vicinity then act as the next layers of protection. They shunt the current from the phase to the ground. Like the ramparts and bastions of the fort, they block the current surge from entering the utility. The result: constant, uninterrupted power supply from the utility to the consumer.
This concept of robust fortress-like protection for the utility is provided by the PEXLINK solution. This is an LSA concept from ABB that minimizes disturbances on overhead lines resulting from unforeseen impulse overvoltages. The PEXLINK concept offers secure and robust performance to improve line availability and the reliability of the electricity supply.
Watch the video on the PEXLINK solution here: