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Variable Power Factor as a Load 2

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tctctraining

Electrical
Nov 17, 2008
118
I need to simulate a load with variable power factor for testing purposes. Aside from using cap banks and inductors , I am thinking to use a Synchronous Generator and a voltage regulator to do this. There are couple issues that I appreciate your feedbacks.
1) Is this option feasible?
2) How much variation of power factor do I get.
3) Is reactive power control different from voltage control?
4) Does anybody know of manufacturer of controllers with least expensive parts?

Thanks
 
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As you lower the voltage the VARs will drop. But I suppose that you may want to stat your test with zero or very little VARs. That means zero voltage and the motor won't run. Using another motor to keep the motor spinning will supply the losses (except the heating caused by the magnetizing current) and will allow the motor to absorb VARs at close to zero volts.
If you have a large transformer available, it may be used instead of the motor as per sibeen's suggestion.
The air gap in the motor demands many more VARs per inch than iron and as a result a motor can be expected to absorb more VARs than a transformer of similar kW rating.
But when you compare the cost of two motors to the cost of a larger transformer it may be feasible. And if you have a suitable transformer available, by all means use it.
Thanks sibeen.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
There is a company in the US that specializes in building lab bench setups for training. I have used some of their products. They have in their catalog a synchonous motor (fractional HP) and a Prony brake. When coupled with the appropriate power supplies and metering, one can run a synchronous motor through the entire repertoire of operations including the VAR scenarios you desire.

Unfortunately the neurons in my brain that hold the name of that company died. I seem to remember that the Name begins with and "H", though.

old field guy
 
Hi oldfieldguy;
Your Cadillac solution sure trumps my compact solution. It stimulated some neurons and brought back memories of some training stints a long time ago.
Your post solidified a thought that was running around in the back of my mind and compelled me to Google.
tctctraining;
See
if the budget will handle it, consider this equipment.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
waross--

I restarted those neurons a split second before reading your post.

Yes, those are the people.

I had the good fortune to have access to a very complete set of their training aids at one time and I used the synchronous motor to demonstrate power factor correction using over-excitation and other operations.

This IS the top-line set-up for demonstrating various electrical power devices.

old field guy
 
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