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mahi7
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Electrical Machine

09/13/2014 5:42 AM

why don't we give DC supply to the stator of synchronous motor?
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kvsridhar
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#1

Re: electrical machine

09/13/2014 6:46 AM

Because we are likely to lose our job immediately

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adreasler
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#10
In reply to #1

Re: electrical machine

09/15/2014 10:01 AM

Had to give you a GA on that, short, sweet, to the point, and it made me have to wipe coffee off my computer screen.

It's nice to be able to have a laugh in the morning at work.

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SolarEagle
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#2

Re: electrical machine

09/13/2014 6:56 AM

The rotor is only used to create a magnetic field, the DC voltage creates a constant stable field....

The stator creates the rotating field that drives the motor....

http://www.electricaleasy.com/2014/02/synchronous-motor-construction-working.html

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mahi7
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#5
In reply to #2

Re: electrical machine

09/13/2014 9:45 AM

thank you soon much I understood well
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Unredundant
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#6
In reply to #2

Re: electrical machine

09/13/2014 10:02 AM

This is the point at which Tesla and Edison parted ways. Edison claimed that AC was merely confused DC.

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Unredundant
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#8
In reply to #6

Re: electrical machine

09/13/2014 9:21 PM

"A repulsion motor is a type of electric motor for use on alternating current (AC). It was formerly used as a traction motor for electric trains (e.g. SR Class CP and SR Class SL electric multiple units) but has been superseded by other types of motors and is now only of historical interest. Repulsion motors are classified under single phase motors. In repulsion motors the stator windings are connected directly to the AC power supply and the rotor is connected to a commutator and brush assembly, similar to that of a direct current (DC) motor.[1]" Wickapedi search "repulsion start, induction run" Note: similar to that of a direct current (DC) motor". Note: almost on topic.

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redfred
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#3

Re: electrical machine

09/13/2014 8:45 AM

Think about the definitions of both concepts of synchronous and the electrical concept of direct current with respect to time.

Now, I suspect (hope) you asked this question looking for a better answer than "that's why their called..." because you have a deeper question like; If a DC supply were applied to the stator windings while an AC supply gets applied to the rotor windings of a synchronous motor would the motor still work at all? Will it work as well? If it won't work as well, why?

Please, ask your deeper question.

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lyn
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#4

Re: electrical machine

09/13/2014 9:33 AM

You can use DC. If you switch the polarity 50, or 60 times per second.

No, wait. That's alternating current.
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Rixter
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#7

Re: electrical machine

09/13/2014 3:50 PM

Synchronous motor turns at speed proportional to AC frequency. DC is zero frequency, so motor won't turn.
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HiTekRedNek
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#9

Re: Electrical Machine

09/14/2014 10:07 AM

There is much confusion in the application of the term "Synchronous motor" versus "Induction Motor".

A true synchronous motor does not require rotor slip to perform work.

An induction motor always requires the rotor to "Slip",or lag behind the rotating stator field to produce work.

True synchronous motors are used where precise speed is required,and are usually small,such as clock motors,etc.

However,there are larger versions that are used for power factor correction,whereas a DC voltage is applied to the stator to increase or decrease the power factor.

Here is a link that explains in greater detail.

Let this be the start of your discovery of electric motors.

The associated links can lead to more and more knowledge.

I hope you enjoy your journey.

https://en.wikipedia.org/wiki/Synchronous_motor

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adreasler (1); HiTekRedNek (1); kvsridhar (1); lyn (1); mahi7 (1); redfred (1); Rixter (1); SolarEagle (1); Unredundant (2)

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