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It isn't unthinkable that the motor is 'derated' to match the AZD DMOC controller output and that paired with a more powerful controller this motor will 'come alive' .
Now we are on the same page here. I have been looking more close at the datasheet of the Motor and remembered one thread posted by a user Coulomb. There is a mention about
S2: 3 min 20KW per 1000 U/min at 280A rms /
see
http://www.diyelectriccar.com/forums/showthread.php?p=330954#post330954

This means you could theoretically draw out 150KW for 3 minutes at 7500U/min if you can hold 280A rms at this speed (you have only 40KW at 2000 U/min). I very much doubt. but that it would be possible to hold this for faster speeds, but if rpm is faster than 5000, you would most possibly be using mechanical gearing if more torque is needed.
 
This document seems to be genuinely from Siemens.
http://media3.ev-tv.me/Azure300VDC-400Acurve.pdf

It states 298Nm at 400A, 300V.

Extrapolating that torque/Amp relationship at higher current levels you get:
(obviously there are some increasing losses, these are just ballpark numbers)

370Nm at 500A
440Nm at 600A
520Nm at 700A
590Nm at 800A

Crank the voltage up to 400V (350V full load), and it should pull pretty good up to about 3500-4000 rpm.

Now we are talking.. :cool: :eek:
 
This document seems to be genuinely from Siemens.
http://media3.ev-tv.me/Azure300VDC-400Acurve.pdf

It states 298Nm at 400A, 300V.

Extrapolating that torque/Amp relationship at higher current levels you get:
(obviously there are some increasing losses, these are just ballpark numbers)

370Nm at 500A
440Nm at 600A
520Nm at 700A
590Nm at 800A

Crank the voltage up to 400V (350V full load), and it should pull pretty good up to about 3500-4000 rpm.

Now we are talking.. :cool: :eek:
Extrapolating that torque/Amp relationship at higher current levels you get:
Although this is an acceptable approximation with series wound DC motors, it is invalid to use for induction motors. Going beyond the manufacturer's stated maximum torque or current is undoubtedly past breakdown torque.
 
This document seems to be genuinely from Siemens.
http://media3.ev-tv.me/Azure300VDC-400Acurve.pdf

It states 298Nm at 400A, 300V.
Ok this shows that you can drive the motor on 400A for 0,5 minutes (it has been stated on other datasheets/plates that it can been driven at 280A for 3 minutes).
I would think that this is the maximal current but I thought also before 300A was it. The theoretical limit seems then going to 200 kW (assuming the 500V version could do that too)
So who is going to make a try with a 10.000 Euro controller to prove that?:)
I know Ballard did with 138 series, and was smoked bad (Powered by a fuel cell, this was a bus project)
 
Discussion starter · #67 · (Edited)
Now we are on the same page here.

ruckus said:
Quote:
Originally Posted by ruckus
It isn't unthinkable that the motor is 'derated' to match the AZD DMOC controller output and that paired with a more powerful controller this motor will 'come alive' .
Yeh, but where might one find a 'more powerful controller'?
BTW, this was a joke... I wasn't actually agreeing with him
 
Discussion starter · #70 · (Edited)
So those charts were made with a 250A controller?
No, they're just the ratings at for 10minute continuous use at 35deg ambient with 8 l/min water cooling. This is the limit of the motor to withstand that power for 10mins - which is a long time by the way, and 70kW for 600seconds is nothing to scoff at.

The document later states "The cooling system was found to be quite
powerful: the limiting temperature of the inverter was never achieved, a reduction of power output was always due to the machine winding temperature." - And it's a 400A controller, so that should put your concerns at ease.

A peak of 70kw isn't gonna give it much of a leg up on the HPEVS systems.
A higher peak is given on the Siemens data nameplate as 3min rating, or 0.5min rating in the graph you linked.
The HPEVS is probably rated peak for <1min for marketing purposes (though i know nothing about the motor and haven't checked), you've got to compare apples with apples - and probably what's the most relevant is the continuous ratings. Some manufacturers rate at 60min, if so, the graph I provided shows about 55kW cont @ 35degC ambient.

If Siemens says the maximum current is 280A RMS (~400A peak) for <3mins, I'm inclined to believe them. You can push it harder say for 10seconds with diminishing returns if your only increasing current (hitting saturation), but it may take 10seconds to hit 150deg from 35deg, but 5minutes to cool back down to 35deg to do it again. Also if your increases the temp so quickly, you need very fast response of sensors and controller to turn it off in time without doing permanent damage to the motor.

It sounds like you are after a more powerful motor, then buy the 5138 or a PM motor.
 
It sounds like you have a very interesting document there. Is it available online?

Just curious what the 215V version might be able to do since there are now quite a few out there after the AZD sale.

Yes, there is nothing beyond the point of saturation except destruction, but the critical question is the amps just before saturation. I think 298Nm at 400A is fairly close, but not quite the limit.

I am sure that somebody will push that limit soon enough. Knowing humans :rolleyes:
 
Well I haven't seen the inside of a DMOC 645 but inside AZDs latest rendition of controller the 845 they were using SKiM 606GD066HD modules rated at 440 amps at 70C or if you can cool the junction down to 25C then your rated to 550 amps. Not bad for a footprint thats only 10cm x 15cm.

Attached pics of these controllers. I have more than one. Same controllers as on the 645 (TIs 28F335 and 470 Cortex M3 device).
 

Attachments

Cool. :cool:

Just to clarify, the Semikron Skim606GD066HD is rated at 641A at 25C and 512A at 70C. The nominal rating of 600A is good up to about 105F (42C).

I have the 606 in the Scott Drive 200 that is going into the 36 IH with the BLDC, PMAC, or whatever you want to call it.

While it is capable of over 250kva peak, with battery sag, some heat, and motor losses I figure roughly 180kw output.
 
Discussion starter · #76 ·
A 400A+ IGBT? Sounds interesting. What is the limit?
Depends what power stage I put on it.
ATM using 1200V 300A IGBTs, but also have a bunch of 600V600A IGBTs to blow up for 'research'. The final version for my project will be on a 600V900A brick


You spoke poorly of the DMOC which is also a 400A controller. Any particular complaints against it, or just that it is your competition?
I have seen/researched a few control/driver boards from across the models, and I don't like the design personally. Picked out a few component p/n's which seemed borderline spec'd, 2 layer boards, some crucial traces seemed too long & too many via's with no stitching caps, etc. I'm very picky though.

Also, at the time it wasn't working yet people were still charging a premium for them... but I now see some people have got it spinning the Siemens motor which is cool, and now justifies the price.

So no, not competition, all I meant was I wouldn't buy it over some of the better known brands.


Sounds like you are going into the controller business. :)
Nope, just writing a thesis on induction motor control.
If I was going into business, I wouldnt of given away my schematic and code to so many people.
 
Also, at the time it wasn't working yet people were still charging a premium for them... but I now see some people have got it spinning the Siemens motor which is cool, and now justifies the price.
Any links to people who have it working?
 
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