Correct Answer - Option 2 : shunt reactor
Ferranti effect:
- The effect in which the voltage at the receiving end of the transmission line is more than the sending voltage is known as the ''Ferranti effect.''
- This type of effect mainly occurs because of light load or open circuit at the receiving end.
- VR > Vs
- Ferranti effect is due to the charging current of the line.
- Ferranti effect is not a problem for short transmission lines because there is no capacitance effect
- Ferranti effect means receiving end voltage is greater than sending end voltage
- This phenomenon occurs in medium and long transmission lines which are at lightly loaded or no-load condition. This is because of capacitance effect
How to reduce Ferranti effect:
- This effect 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.
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Synchronous phase modifier(SPM) is used as under excitation it works similarly to shunt reactor which absorbs lagging reactive power and delivers leading reactive power.
The value of the shunt reactor is given by
\({X_{sh}} = \frac{B}{{1 - A}}\)
where A and B are T-parameter of the transmission line
