The best location for use of a booster transformer in a transmission line is

A. at the sending End
B. At the Receiving End
C. At the intermediate point
D. anywhere in the line

Answer: C. At the intermediate point 

Explanation:

Booster Transformer

• Booster transformer is one which is often used towards the end of a power line to raise the voltage to the desired value. 
• It is used for controlling the voltage of a feeder at a point far away from the main transformer.
• Booster transformers are used to eliminate the stray currents and the disturbances, obliging the return current to flow to the return conductor.
• Booster transformer is used in railways for eliminating the flow of stray current. The stray current disturbs the communication system and also damage the electronic devices of the trains passing through them.
• They are used to maintain uniform voltage along the line that have distributed load, the voltage drops due to serial resistance is compensated periodically with a booster transformer, otherwise the voltage given to first users will go too high and last users too low.
• Booster is low voltage high current series wound DC generator inserted into a DC circuits to add or inject a certain voltage proportional to the circuit current. The main purpose of providing booster in power system is to compensate the voltage drop of feeder.
• Booster add voltage to the feeder and compensate the voltage drop. Hence it increase the efficiency and reliability of the system. 
• That is why it is one of the important device of power system.
• A booster transformer is used towards the end of a power line to raise the voltage to the desired value. It is used for controlling the voltage of a feeder at a point far away from the main transformer.
• The secondary of the booster transformer is connected in series with the line, and its primary is supplied from the secondary of the regulating transformer.
• Booster transformer is used in railways for eliminating the flow of stray current. The stray current disturbs the communication system and also damage the electronic devices of the trains passing through them.