1 Answers
Chetan Shidling Staff answered 5 years ago
The advantage and disadvantages of the D.C. transmission system.
Advantages.
- It needs only two conductors as compared to three for a.c. transmission.
- There is no inductance, capacitance, phase displacement and surge problems in d.c. transmission.
- Due to the lack of inductance, the voltage drop in a d.c. transmission line is smaller than the a.c. line for the same load and sending end voltage. For this reason, a d.c. transmission line has better voltage regulation.
- There is no skin effect in a d.c. system. Hence, the entire cross-section of the line conductor is utilized.
- For the same working voltage, the potential stress on the insulation is smaller in the case of d.c. system than that an a.c. system. Therefore, a d.c. line needs less insulation.
- A d.c. line has smaller corona loss and decreased interference with communication circuits.
- The high voltage d.c. transmission is free from the dielectric losses, particularly in the case of cables.
- In d.c. transmission, there are no stability problems and synchronizing difficulties.
Disadvantages
- Electric power cannot be generated at large d.c. voltage due to commutation problems.
- The d.c. voltage cannot be stepped up for transmission of power at large voltages.
- The d.c. switches and circuit breakers have their own limitations.