what r the effects on no load current due to operation of a transformer below rated frequency at rated voltage

Question

Specific answers please.

Answer 1

operating a transformer below rated frequency result in less efficiency. A transform works by "changes" in magnetic fields intensities, in a transformer's case, switching directions. This change, the greater, in terms of fastest change or greatest delta in field intensity per time, results in an output. The primary winding "couples" to the secondary winding via the magnetic core, usually an electrical steel, or sometimes called silicon steel.

A transformer is designed to be most efficient at its rated frequency, operating it at high or lower frequencies will result in inefficiencies, in higher frequencies, due to inductance causing higher impedances, or too low a frequency resulting it lowering the delta of the magnetic field intensities.

You should see a lower then expected peak voltage on the secondary winding output in no load conditions.

If you are interested in these things, look up tesla coils, These are simply very high ration step-up transformers run in the no load condition. A high voltage current discharge via HV capacitors, is sent into the primary winding, resulting in extreme voltage build-up on the Non-loaded secondary winding. This voltage reaches so high, that it breaks down the dielectric strength of "air" and arcs current threw plasma (aka the spark) to reach ground. Basically a lightning machine. Some even make is a hobby, and call themselves "coilers" That mast they use, and stick large aluminum ball son top of, is just a Step Up transformer, the windings are wrapped around the mast, leading to the top.

Here is a nice picture

http://members.iinet.net.au/~will2/tesla-coil.jpg

feel free to email me

Answer 2

You need to be more specific.
How much lower Hz?
As the Hz falls so the magnetizing current falls as well, BUT it has very little effect on with frequency excursions of around 5%
Source: Electrical Engineer with 40+ years experience

Answer 3

my favorite transformer is megatron.