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Where to find high frequency VFD?

xg1745

Plastic
Joined
Jan 17, 2011
Location
AB, Canada
I am looking for a high frequency VFD 400-700Hz. Everything I can easily find tops out a 400Hz but I need 660 for a 40k spindle. Any idea where to look? Thanks.
 
Open loop is fine, Is there any advantage to SVD drive in this application? (from my understanding it is more for low end torque, this one will be at minimum 400hz 24k rpm) Abs position is also not important.

It is a 2 pole 2.2KW 230v motor, I would prefer to run it from single phase so probably a 7.5hp drive? Cost and shipping to Canada are also important.

Thanks.


open loop?
sensorless vector?
v/hz style?
vector?
voltage? current?

we offer all of the above.
 
Not many drives go to 800Hz output, it's usually the most expensive "Universal" drives that can be configured as VFDs or Servo drives that will. The Control Techniques Unidrive is one of those, as is the Siemens S120. But not all of their other models in the same brand do it.
 
I picked up a brochure on Lenze AC Tech SMVector drives at Armature Electric in Vancouver BC this AM. The brochure indicates that the output frequency is up to 500 Hz with 1000 Hz optional. I went to their website to look for more info and found a newer version of the brochure but it doesn't seem to show the option. (http://www.actech.com/documents/saleslit/CB-SMV-1211-e1.pdf). Might be worth contacting Lenze AC Tech to get the scoop.

Technically, to increase the output frequency the motor's back EMF may have to be reduced or the DC bus voltage increased. The PWM switching frequency usually gets increased too but this leads to greater power losses and heating. This may have something to do with the 1000 Hz option being dropped from the above brochure. The embedded microprocessor and waveform generation logic also ought to be faster. These are needed for vector operation so it's more likely to find a vector drive with a higher output frequency - no guarantee though.

Hope this makes sense,

Cheers,

Duane
 
should the OP be looking at a 600v system so as to get better v:hz ratio and increased hp at higher frequency?
Rob
 
should the OP be looking at a 600v system so as to get better v:hz ratio and increased hp at higher frequency?
Rob

Depends - every spindle manufacturer that I have worked with rates the spindle at an elevated frequency at 200 or 400 volts. Typically - I have seen 50Hz ratings at 100V (2V/Hz) which would mean that the synchronous frequency of the motor at 480V feed would be 240Hz and constant HP region extending to ~500Hz . . . and typically you would want to set the drive up to run 6-12 kHz switching frequency.
 
Unfortunately the motor does not have the leads to up the voltage. I have found a couple of Lenz, a Hitachi and some imports that can do it. But I could not find anyone to actually sell me one yet (at least easily in stock and shipping to Canada).

Duak - Thank you for the info, I will Armature Electric a try if I can't find anyone local. I have give up on used/surplus at this point

From my (very limited) understanding it would not need to be a vector drive as frequency is high and torque control is not important, also wouldn't it be alot more expensive as the processor would need to keep up with higher output frequency as opposed to a dumb timer? Hardware closed loop seems impractical at this speed and (also no need for abs positioning)

eBay has a few import drives that claim output up to 2.4khz, but that does not make sense to me. PWM switch rate maybe but not output?
Also last time I got one of these capacitors were not soldered (actually fell out) and some diodes were in backwards, barely got it working.

Thanks.
 
Try the Iranian craigslist; you may find some "needing work". :)

I understand that 1200 hz is used on uranium centrifuges, but be prepared to answer some questions, from people who don't smile.

My source: Page 18, of http://fissilematerials.org/library/gfmr10.pdf

Since October 2010, various reports began to suggest that a sophisticated computer malware
(worm) attack may have targeted Iranian nuclear facilities for more than a year,
which could help explain why the number of operational centrifuges at Natanz began
to decrease after May 2009.70 In November 2010, Symantec published a detailed report
analyzing the malware (Stuxnet). The report confirms that the worm is most prevalent
in Iran (more than 60 % of infected hosts) and designed to sabotage industrial control
systems and, even though not explicitly considering enrichment plants, reveals that
frequency converters (operating between 800 and 1200 Hz, i.e., a typical frequency
range for gas centrifuges)
are the main target of the attack.71 In late November, some
reports suggested that Iran had temporarily halted all enrichment activities.72

Does 700hz qualify as "dual use", and subject to greater scrutiny?
 
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no quote?

....But I could not find anyone to actually sell me one yet (at least easily in stock and shipping to Canada)......

We did, didnt we?? Made in USA in MI by the original designer of first & best 3000hz vfd drives anywhere; we can usually ship same or next day whenever required! Standard product too, no spl option... we even preload the drive with your motor data for plug n play if u give us the motor data..... the hitachi we sell should be able to ship same day too....
 
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Unfortunately the motor does not have the leads to up the voltage.

If you are running the motor above its "nominal" frequency, then it will accept a voltage in proportion...... a 230V motor will run on 460V at 120 hz.

Naturally, the motor insulation needs to be rated for that, but a 230/460 motor would happily run on 460V 120 Hz when wired for 230. You get double HP from nominal.
 
careful......

ur motor is rated 380v @ 400hz @ 12,000rpm.

It is good to 380v @ 500hz @ 15,000rpm.

Then it begins to drop off in kw as it goes faster:

380v @ 733hz @ 22,000rpm

then lastly 380v @ 933hz @ 28,000rpm.

So, buy a 0-240hz drive and u will only go 3,600rpm max.
So buy a 0-400hz drive and u will only go 12,000rpm max.

Buy a 933hz output drive and go all 28,000rpm!

We sell the only USA made and designed 3,000hz output high performance vfd drive. PM me for a quote if you wish.
 
Hey Mike,
Yes the spindle rated 380 @400hz 12,000rpm, but my client requested for Max speed 22,000rpm, looking for 800Hz inverter.
 
Refu.de (std to 1000hz, 3000 as option, vector or v/hz)
spindel.com (3 models, 400, 800, 3000hz v/hz)
hitachi.com (std 400, 800 is std option, v/hz or sensorless vector)
danfoss (just saw one of their 1000hz v/hz models.

Those are just off the top of my head...... So it seems you do have quite a few options.....I would caution against going faster than the max speed the motor is rated for - just because your client 'wants' double the speed is not good reason to supply it w/o homework. The cetrifigal force can throw those rotor bars when max rated is exceeded. Ever see or hear that happen? You don't want to....

Don't laugh at the nuclear bomb making stuff; seems some countries that start with the letter i are always looking for this technology (which of course is restricted for shipment to them).
 
Vacon as well, in fact, they are the drive suppliers targeted by the stuxnet worm in the Iranian centrifuge debacle (i say debacle only because it was found out about).

There are a number of new very large (as in 350HP) high speed turbo blower designs being used now in the wastewater industry that require 1200Hz output from the drives, they run at 65000rpm using 2 pole motors. I just had to investigate this because our company stops at 750Hz now, and engineering wanted to know what the market is for large drives at that speed. I shudder to think of something that big spinning that fast! I hope the walls of that equipment room are thick reinforced concrete...
 
Hey Mike,
Yes the spindle rated 380 @400hz 12,000rpm, but my client requested for Max speed 22,000rpm, looking for 800Hz inverter.

Spindle is rated for 12K and you want to spin it 22K.
Electrical would be the least of my concerns.
I hope you have done your home work on the construction and bearings and know why it is rated at 12K.
Going fast is a bit more involved than just pumping up the frequency.
Bob
 








 
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