Why should be the frequency is 50 hz only why not others like 45, 95 56 or anything , why should we maintain the frequency constant if so why it is only 50 ?
Answers:
We can have the frequency at any frequency you like, but than you must also make your own motors, transformers or any other equipment you want to use.We maintain the frequency at 50hz or 60hz cos the world maintains a standard at 50 /60hz and the equipments are are made to operate at these frequency.
The reasons for power supply frequency in India to be 50 Hz and in US to be 60 HZ are:
1.ENVIRONMENTAL FACTORS
The average annual temperature of India is greater than that of US.
2.POWER GENERATION REASONS
To generate power of that frequency it costs a lot and the size of the alternator is huge and it costs an incredible amount which we cant afford.
3.EDDY CURRENT LOSSES
As frequency increases eddy current and hysteresis losses increases and hence power loss also increases.
In US the frequency is 60 Hz and 110 V supply. In India it is about 220 V, 50 HZ supply. For a particular load say 100 KW, the current will be 0.416 A, but in US the same load will consume about 0.9 A. Here the thing is, the heat produced in the cable because of the flow of current will be large in US compared to India. Since US is a cold country they can use this level but not by India.