In which of the following cases Ferranti on long overhead lines can't be experienced?

1. The line is lightly loaded

2. The line heavily loaded

3. The power factor is unity

Ferranti Effect:

• The effect in which the receiving end voltage is higher than sending end voltage in the long transmission line.
• It mainly occurs because of a light load or open circuit at the receiving end.
• It is due to the charging current of the line.
• When an alternating voltage is applied, the current that flows into the capacitor is called the charging current.
• The charging current increases in the line when the receiving end voltage of the line is larger than the sending end.
   

Method to Minimize Ferrant Effect:

• This voltage can be controlled by placing the shunt reactors at the receiving end of the lines.
• A shunt reactor is an inductive current element connected between line and neutral to compensate for the capacitive current from transmission lines.
• When this effect occurs in long transmission lines, shunt reactors compensate the capacitive VAr of the lines and therefore the voltage is regulated within the prescribed limits.

Ferranti on long overhead lines can't be experienced when

• The line heavily loaded.
• The power factor is unity.