The comparison of a.c. power supply and d.c. Power supply is given below:
Merits :
(i) The generation cost of a.c. is less than that of d.c.
(ii) It can be made available in wide range of voltages using transformers.
(iii) The a.c. devices such as motors are mechanically more robust and stout than the d.c. devices.
(iv) The power loss in a.c. transmission is negligible as compared to that in d.c. transmission.
(v) The a.c. can be easily converted to d.c. The reverse is not true.
(vi) For reducing the alternating current, we can use choke coils in which the loss of energy is much less than that in the rheostat used for reducing d.c.
Demerits :
(i) The a.c. is more dangerous and fatal than d.c.
(ii) The 220 V a.c. supply has the peak value of about 311 V which can cause more severe shock to the persons coming in contact with it.
(iii) The a.c. is transmitted mostly at the outer surface of the wire, and so the conductor needs to be in the form of several stranded wires.
(iv) The a.c. contains higher harmonics in addition to the fundamental frequency.
(v) The a.c. cannot be used for electrolysis, electroplating, electro refining, electro-typing, etc.
