Induction Furnace
Author: Srinivasan
A Furnace is a device used for heating. The term furnace is used exclusively to mean industrial furnaces which are used for many things, such as the extraction of metal from ore (smelting) or in oil refineries and other chemical plants, for example as the heat source for fractional distillation columns.
An Induction Furnace is an electrical furnace in which the heat is applied by induction heating of a conductive medium (usually a metal) in a crucible placed in a water-cooled alternating current solenoid coil. The advantage of the Indution Furnace is a clean, energy-efficient and well-controllable melting process compared to most other means of metal melting. Most modern foundries use this type of furnace and now also more iron foundries are replacing cupolas with induction furnaces to melt cast iron, as the former emit lots of dust and other pollutants. Induction Furnace capacities range from less than one kilogram to one hundred tonnes capacity, and are used to melt iron and steel, copper, aluminium, and precious metals.
Operating frequencies range from utility frequency (50 or 60 Hz) to 400 kHz or higher, usually depending on the material being melted, the capacity (volume) of the furnace and the melting speed required. Generally the smaller the volume of the melts the higher the frequency of the furnace used; this is due to the skin depth which is a measure of the distance an alternating current can penetrate beneath the surface of a conductor. For the same conductivity the higher frequencies have a shallow skin depth - that is less penetration into the melt. Lower frequencies can generate stirring or turbulence in the metal.
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Is it possible to modify 3 phase Induction motor to Generator?
3 phase 400 volts say 10 kw motor .This may be a funniest qestion.This doubt is there for more than 20 years. can I try to totally change rotor with magnet or with windings with seperate excitation.brief Answer requested
Yes you can add slipring (extenal exitation)or with permanend magnet which should not cost more
what do I need to run a/c induction motor from a generator?
Specifically If there is anything in between like inverter /controller, regulator,transformers,etc. and good sources for info and/or purchase.
I would need to controll the speed of the motor.So I would need some type of controller correct?And any info to get this would be helpful.Thanks.
What is the minimum rating of a generator which is sufficient to start an induction motor direct on line?
A general safe rule is required indicating ratio of generator to motor rating
The synchronous electric generator and motor. 10 points promised?
Who invented them? I can’t find it.
If nobody can find it, can they please tell me whether it was Tesla’s work that lead to the synchronous electric generator and motor? I know Tesla invented the induction motor and generator, and the synchronous machines are really a form of these. Just slightly changed.. If so, I can just say that.
Thanks in advance. 10 points for best answer.
It is possible to couple 3phase AC induction motor and AC generator ?
You don’t need anything generators produce ac as long as the generator produces enough power to run it you should be alright. If your talking car generator then you need an inverter. check the mail order catalog Nothern tool and equipment you need to know output power of the source and load rating of the motor to be sure you can run it.
It depends on the electric motor rating.With a 75 KW generator,40Hp motors could go on line by direct on line starters.It might be safe to say 2kw per motor Hp. would be safe to start motors by DOL starters.
In order to invent a DC generator with a commutator, it would have been necessary to realize that the current in a loop of wire rotating in a magnetic field changes direction as the loop rotates. A commutator is essentially a mechanical rectifier that rectifies the alternating current that is generated in the rotating wire coils and provides a rotating connection to conduct direct current away from the rotor. However, the developers of DC generators would have considered the alternating current in the rotor to be a problem to be solved rather than something useful. Once Tesla proved that alternating current was something useful, various approaches to building an AC generator would have been obvious to anyone who knew how to build a DC generator.
Wikipedia has a huge amount of information and lots of links from one article to another in Wikipedia as well as links to external sources. Most of the information is quite accurate, but there are errors and exaggerations. Here is a page of links to articles related to electric generators:
http://en.wikipedia.org/wiki/Category:Electrical_generators
If it is possible, likely it has been done. See the link.
yes, you can couple them directly if they are both rated at the same RPM, or via a gearbox or pulleys to get the RPMs to both be at the proper value.
This assumes you have the proper source of 3 phase AC.
But I don’t know why you would do this? You will get an AC voltage that is not very stable in voltage or frequency, unless you provide feedback controls.
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