Question

HVDC transmission is economically used for underground cables of length more than:
1. 25 km
2. 10 km
3. 50 km
4. 30 km

Answer 1

Correct Answer - Option 3 : 50 km

Explanation:

• HVDC links interconnect two AC systems that are not synchronous i.e. two AC systems operating at a different frequency.

• HVDC systems use D.C. for transmission of bulk power over long distances.
• HVDC transmission is economical only for long-distance transmission lines having a length more than 600 km and for underground cables of length more than 50 km.
• For long-distance power transmission, HVDC lines are less expensive, and losses are less as compared to AC transmission.
• Converter substations used at both the sending and the receiving end of the transmission lines generate harmonics which can be reduced using filters.