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Re: Question about power capacity of electrical motors.

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On 7/22/2017 2:36 AM, Tim Williams wrote:
>>> "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> wrote in message
>>> news:oksjee$qt5$1@dont-email.me...
>>>> However, I've heard of cases of high intensity magnetic fields where
>>>> you can get continuous, sustained fields significantly higher than 
>>>> this:
>>>>
>>>> Orders of magnitude (magnetic field).
>>>> 11.7 T 117 kG Field strength of a 500 MHz NMR spectrometer
>>>> 16 T 160 kG Strength used to levitate a frog[14]
>>>
>>> About at this point, even the best superconductors, at LHe temperature,
>>> can't sustain operation.  These two cases, and many at lower intensities
>>> (including thousands of MRI machines in the 1-5T range), are all
>>> superconducting.

The question in regards to magnetic field strength in electric motors is 
whether increasing the power by increasing the current is limited by 
magnetic saturation of the core material. This magnetic saturation is at ca. 
2.2 T ( tesla) for ferrite cores. But do large electric motors commonly 
approach this value anyway? This is higher for example than the highest 
magnetic field for permanent commercial magnets made of neodymium, at ca. 
1.3 T:

https://www.first4magnets.com/tech-centre-i61/information-and-articles-i70/how-is-the-strength-of-a-magnet-measured-i81

But these magnetic fields of neodymium permanent magnets are so strong they 
could crush your hand if you placed it between two neodymium magnets you 
could fit in your palm. So I'm inclined to think the magnetic field 
strengths generated by electric motors are not that strong.

Anyone know what are the strengths of the magnetic fields commonly generated 
by large electric motors.


   Bob Clark


----------------------------------------------------------------------------------------------------------------------------------
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while maintaining their strength.

Some proposals to accomplish that here:

From Nanoscale to Macroscale: Applications of Nanotechnology to Production
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American Journal of Nanomaterials.
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http://pubs.sciepub.com/ajn/4/2/2/
----------------------------------------------------------------------------------------------------------------------------------

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Re: Question about power capacity of electrical motors. "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-07-21 19:36 -0500
  Re: Question about power capacity of electrical motors. Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2017-07-22 10:39 +0200
    Re: Question about power capacity of electrical motors. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2017-07-22 12:47 -0400
      Re: Question about power capacity of electrical motors. edward.ming.lee@gmail.com - 2017-07-23 08:07 -0700
      Re: Question about power capacity of electrical motors. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2017-07-26 18:18 -0400
        Re: Question about power capacity of electrical motors. "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-07-26 18:27 -0500
  Re: Question about power capacity of electrical motors. "Robert Clark" <rgregoryclark@gmSPAMBLOACKail.com> - 2017-07-22 11:40 -0400
    Re: Question about power capacity of electrical motors. "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-07-23 14:32 -0500

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