Ferranti Effect in HV Cable Systems 
When a long high voltage cable is energized with little or no load the voltage at the receiving end can become higher than the voltage at the sending end.
This is known as the Ferranti Effect.
The reason is that HV cables have high capacitance, which generates charging current and reactive power along the cable route.
If not controlled this voltage rise can:
Cause overvoltage in the network Increase stress on equipment insulation Affect system stability and reliability
To reduce this effect, utilities install shunt reactors.
A shunt reactor absorbs excess reactive power generated by the cable and helps keep the system voltage within safe limits.
In many long HV cable circuits, the shunt reactor is not just an option it is an important part of the system design.
Understanding cable systems is not only about carrying power but also about controlling the electrical effects that come with long cable routes.
