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Post by Tritium_James » Mon, 12 Apr 2010, 19:44

Tritium is pleased to announce the release of our new AC motor drive - the WaveSculptor 200 - specifically designed for EVs.

Brief specs are:
Power Rating: 165kVA peak, 75kVA at 50°C continuous, 100kVA at 30°C, liquid cooled
Motor Type: Three-phase permanent magnet (BLDC) or Induction
Cruise Efficiency: >97%
Environmental Rating: IP65
Maximum Battery Voltage: 450V DC
Maximum Motor Current: 300Arms
Communications: CAN bus
Dimensions: 500 x 172 x 82mm
Mass: 8kg
Price: A$6000 + GST for 1-10 units.

More information is available on our website, this product's page is here: http://www.tritium.com.au/products/TRI74/index.html

The datasheet is on that page, and the user's manual will be available later in the week. We also have a range of ancillary items to go with the system, such as a driver controls, and pack safety system (precharge + BMS).

If you've got any questions - please ask!
            

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Post by Electrocycle » Wed, 14 Apr 2010, 06:05

good news!
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Post by Richo » Wed, 14 Apr 2010, 06:33

What does the 450Vdc equate to in number of batteries?
107 x TS cells charged to 4.2V or 140 x TS cells nominal at 3.2V.


So the short answer is NO but the long answer is YES.
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Post by Tritium_James » Wed, 14 Apr 2010, 15:11

Richo, that's right, we were running 108 TS cells with the prototype of this controller in the Civic.

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Post by Mesuge » Thu, 15 Apr 2010, 12:28

James, is the 1200V IGBT version for high voltage setup off the table? You are using external HV contactor/fuse box anyway in your package, right? So, perhaps you might be interested.

In that fashion you (and your customers) can run all sorts of interesting <500VAC motors, apart from industrial ACIMs discussed here, also those basically same cross-licensed systems: ~70-105-120kW @ 4500 rpm perms from SUV-limo hybrids (Ford-Nissan-Toyota). Other prooven motors like HV induction Siemens OEMs come to mind, etc..

I'd guess in aggregate they had to sold throughout 2000s at least 100k of these gargantuan hybridos, understandably not as common as Prius-HSD parts from wrecked cars out of roughly 1.5mega copies produced to date, but definately sourcable material..
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Post by Johny » Thu, 15 Apr 2010, 22:07

I hate to be a typical pain in the butt TJ but I agree that if a 1200V IGBT version (600 to 800VDC DC Bus) was available it would give us hackers more piece of mind that there was a commercial EV 3 phase controller out there. Not sure how much of your controller would have to change, Bus Caps, internal SMPS etc. but worth a cursory glance?
Unfortunately the potential for volume is way less then the current unit but just thought I'd stick my 2 bob's worth in...

Mesuge - your Avatar is 2MB in size - takes a long time to load and I don't even know how you convinced the forum to load it!

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Post by Mesuge » Fri, 16 Apr 2010, 00:29

Johny wrote: Unfortunately the potential for volume is way less then the current unit but just thought I'd stick my 2 bob's worth in...

Mesuge - your Avatar is 2MB in size - takes a long time to load and I don't even know how you convinced the forum to load it!


That doesn't have to be the case, Tuarn's RedSuzi and other projects have shown and as you also are trying to document, it can be done in methodic-safe fashion. And as higher dischargeC prismatic/cylindric cells in the 15-30-40Ah capacities are becoming available it will make even more sense from the compact/lightweight batt. package standpoint. And with this distributed ~12x batt. subpacks approach the BMS/charging nightmare (of HV system) is avoidable. To quote myself, "even the hybrid people went 650VDC years ago".

So, perhaps with more HV conversions running around, there would be an interest in this option, I'd say there is some interest brewing up on other forums. From the other Wavesculptor related threads/posts here I gather James is not using prefab/completed power module from his IGBT supplier, so there will be some design changes necessary, however you can buy the completed unit 1200V from them already, "just" upload the software, we linked it inside the AC Zilla thread.

edit: btw. the avatar thingy was just lame attempt to crash the forums, sorry didn't realize the 2MB joke would be saved by the forum system.
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Post by Tritium_James » Fri, 16 Apr 2010, 01:45

Hah, I knew this topic would get bought up as soon as we released our drive!

Yes, we can do a 1200V version. Our gate drive and other HV parts of the circuit have been designed with the larger clearance and voltage ratings in mind from the start, and we can reconfigure the bus capacitors fairly easily. In fact, we have a 1200V version running already as part of our grid-connect work for a different project.

However, we do not currently have the test equipment - mainly being a 900V battery pack - to do the testing required for the high voltage version at this time. We will also need to re-do all the compliance testing, as this would count as a new product for EMC labelling purposes.

So the real constraint here for not releasing a 1200V version is time. We don't have the manpower to do the extra development right now, we're concentrating on getting the 600V version out the door, along with the associated bits and pieces of hardware, and continuing to refine the software such as the automatic motor tuning and user interface stuff.

For those who are planning on buying an industrial motor, the 450V limit of our new drive isn't really a problem anyway. We have a nice little copper-rotor 7.5kW 4-pole 132 frame motor from SEW Eurodrive, that is rated 100V line-line, as a standard off-the-shelf item. That's a standard voltage in Japan or somewhere similar. It's 90-something percent efficient, was a bit under $2k, and took 5 weeks to get here after ordering. We'll be running it to 3x speed, and Tp/Tn is about 3, so its capable of almost 70kW in short bursts. Most of their range is available in this winding option, so I'm sure there's something with a bit more grunt that would use up the full performance of our new drive. So the higher voltages are not really necessary - something to think about, anyway...

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Post by Mesuge » Fri, 16 Apr 2010, 02:45

Fair enough, thanks for the detailed update.
7.5kW and 90% efficient? So these must be the alongated shape - perm ones, right? I think there is a vintage VW conversion thread with 11/15kW (in HV version) of these with ABB VFD somewhere buried in this forum.
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Post by Tritium_James » Fri, 16 Apr 2010, 13:58

No, it's not that long, and it's actually a lot smaller than our other (older) 132 frame motors that we have around in the lab. The big difference is that it's got a copper rotor, where 99% of other motors on the planet are aluminium. The copper gets you a few percent more efficiency, at the cost of a bit more weight. No permanent magnets either, it's just a normal induction machine.

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Post by Johny » Fri, 16 Apr 2010, 14:49

Thanks TJ. It's really great to hear that the plans have been laid for a higher voltage bus version. I had read about the SEW copper rotor motors when I was researching what/where to get mine. At the time they were too expensive but that has paled into very low significance as the time and other expenses (restoration) have blown out my project - it's good to hear that they (SEW copper rotor ACIMs) are readily available.

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Post by Huub35 » Sat, 17 Apr 2010, 08:46

Tritium_James wrote:

...

For those who are planning on buying an industrial motor, the 450V limit of our new drive isn't really a problem anyway. We have a nice little copper-rotor 7.5kW 4-pole 132 frame motor from SEW Eurodrive, that is rated 100V line-line, as a standard off-the-shelf item. That's a standard voltage in Japan or somewhere similar.

...


Hello James,

this is interesting, I did not find a 7.5 kW motor with SEW that has this high a bd. Could you provide the typecode of this motor, as something like this (a bit bigger though) might be an alternative to the ABB HO motors.

Regards,


Huub

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Post by Tritium_James » Sat, 17 Apr 2010, 13:22

The one we have is a DRE132MC4/FF.

They sell three variants, a DRS, DRE and DRP, indicating Standard, Efficient, and Premium efficiency ratings. The catalog indicates efficiency at 100% and 75% load. However, what is VERY interesting is that for this size motor (132MC4) the power ratings for the S,E & P variants are different (9.2kW, 7.5kW, 5.5kW), so that the 75% rating for the S is about the same as 100% in the E, and 75% in the E is about the same as 100% in the P. If you plot the efficiencies on a graph vs power rating, it comes out pretty close to a straight line. My gut feeling at this point is they are all identical motors, just rated differently. The motor efficiency goes up as you put less power through it, so an 'E' motor is really just an 'S' motor running at about 70% of full power. I may be wrong about this, but it's looking increasingly likely.

The other interesting thing is there is an L variant, which is specified for servo motor use. The mechanical dimensions are identical to the S,E and P variants. My feeling once again is that it's the same motor as the other three, but specified for intermittent use. The exciting thing about this motor is that it's specified for use at 400% of Tn. This is higher than the Tn/Tp for the other three motors, which is tending to reinforce the thinking we (at Tritium) have been trending towards for a while, which is that you can quite easily exceed the breakdown torque (Tp) for these motors when you're running from an intelligent motor drive that can control the D (magnetising) and Q (torque producing) axis currents independently. Obviously at some point you begin to saturate the motor, but my distinct suspicion at this point is that this will happen a long way above the breakdown torque. It may be possible to get very high peak powers from this 7.5kW motor... we're in the process of mounting it on our dyno at the moment, and should know next week how far we can push it.

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Post by Huub35 » Sat, 17 Apr 2010, 14:49

James,

this is very interesting indeed, and matches with a suspicion that I also had for some time.

This might also be related to the discussion we had in another thread (2/4 pole diferences), where we saw the bd ratio of motors being changed from one year to the next (On eof the ABB 132 frame motors is currently under discussion on this aspect).

On of the questions I have in this respect, is what is determining the maximum bd ratio. Jour post indicates that this is depending on the drive control, but I assume there must be also some sort of physical limit? Maybe you can explain a little on this?

regards,


Huub

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Post by woody » Sat, 17 Apr 2010, 15:10

My understanding of the breakdown limit is that it's directly related to the V/F used to drive the motor.
The published BD is usually at 400/50 = 8.
If you exceed this, you get more current, more (over) magnetism, more torque, but less efficency.
Danfoss torque boost does this.
From the ABB motor formulas I have, even with standard V/F, the current increases more than proportionately as you head towards BD - I.E. less efficiency. About 4 x current at a BD limit of 3.
My understanding is that the V/F is rather arbitrary - it is chosen in combination with the nominal power to meet a certain efficiency standard - and with a VFD you can choose your own to suit.
The nominal V/F will involve some overmagnetism, the hysteresis curves are quite gentle to start with.
I'm inclined to agree with James about the "plate engineering" the same motor could be rated at 90% efficient 100Nm with 3x BD ratio, or 80% efficient 150Nm with 2x BD ratio...
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Post by Tritium_James » Sat, 17 Apr 2010, 15:53

Exactly, Woody - as you push them harder at some point you get less torque for your current. But I guess it's all a matter of how much less. The plot of efficiency vs power is quite straight for the region 5.5kW -> 9.2kW, and 91 -> 88%, going from the data I have from the catalogue. How far this continues before getting non-linear I have no idea at this point.

On the other hand, even if it drops to say 75% efficient when you're pushing it to 400 or 500% of Tn, who cares? You only need that amount of torque for literally a few seconds in normal driving. Then you're back to cruising at around nominal torque and the efficiency is up over 90% again.

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Post by Mesuge » Sat, 17 Apr 2010, 22:18

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DRE series, btw. /FF stands for flange mounted w. bores ~= IEC B5
and LC/MC stands for copper cage rotor variant

Color me stupid, but can't see those >90% efficiencies, it's more like 89% nom. >> Catalogue
And if you brutally overclock it as you've done (>8x), with the stock or slightly upgraded aircooling, I doubt the eff. will go up, more likely a bit downwards from that. Your dyno data might differ - pls. explain it for us mere mortals, is it just the nameplate diversion to fit some eff. category/standards? I guess most yearn for the magic 90% eff. boundary for major portion of the cruising regime envelope (accel. portion less so as explained - ok). Beside the 4-6% wasted energy from this e-drivetrain combo in comparison to BLDC setup, just for the psychological reasons, who wants 80% something AC in their car nowadays?? Even the genI Prius over a decade old clunker will be laughting at us all the way (I know he is perm though).. Image
So, is the only option left ponny up to 160 framesize for >90% eff?

Did you order it with the temp sensor&protection options, and are other options like better bearing, winding insulation necessary/suitable? Given the copper cage rotor, any of the better sealing options advisible?

Not complaining, hah, I just have to come to the terms, we have to be greatfull even for this eff. level pushed from a mere 7.5kw/~65kg industrial grade puppy. Alrighty then, apparently ~95% EV motors are reserved for the holly/bollywood people only Image   
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Post by Huub35 » Sun, 18 Apr 2010, 01:25

woody wrote: My understanding of the breakdown limit is that it's directly related to the V/F used to drive the motor.
The published BD is usually at 400/50 = 8.
If you exceed this, you get more current, more (over) magnetism, more torque, but less efficency.
Danfoss torque boost does this.
From the ABB motor formulas I have, even with standard V/F, the current increases more than proportionately as you head towards BD - I.E. less efficiency. About 4 x current at a BD limit of 3.
My understanding is that the V/F is rather arbitrary - it is chosen in combination with the nominal power to meet a certain efficiency standard - and with a VFD you can choose your own to suit.
The nominal V/F will involve some overmagnetism, the hysteresis curves are quite gentle to start with.
I'm inclined to agree with James about the "plate engineering" the same motor could be rated at 90% efficient 100Nm with 3x BD ratio, or 80% efficient 150Nm with 2x BD ratio...


Hi Woody,

if I understand this correctly, then for acceleration you would like to have a different V/F (for the higher torque) then for cruising (where V/F of 8 would lead to published=better efficiency numbers)?

Does this mean that almost automatically we are heading for vector control, as V/F control will not allow this over the whole rpm range (as we know, for low rpm most VFD's have some tricks up their sleeves)?

Wow, the speed that I get learning moments through this forum, amazing and the main reason I am so grateful about this forum!

Regards,


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Post by antiscab » Sun, 18 Apr 2010, 01:32

Mesuge wrote:
And if you brutally overclock it as you've done (>8x), with the stock or slightly upgraded aircooling, I doubt the eff. will go up, more likely a bit downwards from that.


increasing power by increasing rpm also increases efficiency for most motors (basically unless the windings are superconducting or for some reason the fan is still mechanically attached)

Tuarn's bench demonstration showed this

increasing power by increasing torque reduces efficiency (again, unless the windings are super conducting)

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Post by Mesuge » Sun, 18 Apr 2010, 02:15

matt> yes thanks for the reminder - I should have written it more
clearly as to whether James used the stock fan for his dyno tests
and/or what kind of custom/forced cooling setup was it?

-
http://www.drives.co.uk/news/technews/r ... ews426.htm

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Video for Siemens GP100A:

Product sheets and Catalogues

Good short primer on these red squirrels here, they also talk about
more efficient Siemens copper rotor motors, perhaps worthwile exploring
for our purposes, also name 3rd contender in this market, Favi brand.

Interesting "scholarly" short intro paper on the copper rotor subject, they compare Siemens, SEW and others. Identify both as industry leaders in this technology, Siemens comes first, it seems they didn't use for the shoot out the latest DRE (2007?) by SEW, but the older one DTE/DVE series (2003?)? A bit confusing since this was published 1Q/09: -paper-
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Post by woody » Sun, 18 Apr 2010, 06:08

Huub35 wrote:
if I understand this correctly, then for acceleration you would like to have a different V/F (for the higher torque) then for cruising (where V/F of 8 would lead to published=better efficiency numbers)?

Does this mean that almost automatically we are heading for vector control, as V/F control will not allow this over the whole rpm range (as we know, for low rpm most VFD's have some tricks up their sleeves)?
I think the other half of this trick up the VFDs' sleeves is dropping the V/F for reduced torque and increased efficiency - the most extreme example being freewheeling. E.g dropping the V/F to half would only allow 1/4 the torque, but more efficiency.
The current limit of the VFD brings an early end to the party - e.g. a 55kW VFD has about 175A to play with - and a 400V 22kW motor takes 40 amps nominal, ~160 at 3x overload - not much is left for more torque. If you run a 230V motor you won't have enough for 3x breakdown.
Having a huge current available, like the wavesculpter does - is very handy.
I haven't found a good explanation of vector drive though - it's controlling the stator and rotor currents separately - is this just a matter of manipulating the PWM more closely so that the in phase (rotor) and out of phase (stator) currents are better controlled?   
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Post by Tritium_James » Thu, 22 Apr 2010, 22:57

Woody, if you want a good explanation of vector drive you'd better break out the maths textbook :)   But yes the very simple explanation is exactly as you said. The terms you're looking for are the D and Q axis currents.

Also, I've got the user's manual finished and have updated the product page, so scroll down to the bottom to find it. Direct link here: http://www.tritium.com.au/products/TRI7 ... Manual.pdf

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Post by Mesuge » Sat, 24 Apr 2010, 02:14

James, the manual cleared many questions, thanks for that. Btw. would you consider doing some research into these Siemens coppers as well, are they any good for this application? In terms of efficiency they are clearly outperforming the SEW.
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Post by Tritium_James » Sat, 24 Apr 2010, 02:44

The nice thing about the SEW motor is that it's available stock at the very low voltage (100V) version. This means we can spin it to 3x rated speed without needing a very high voltage pack. Unless there are other variants from Siemens (there probably is) then they would need rewinding, which adds to the cost and might result in lower efficiency too.

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Post by coulomb » Thu, 06 May 2010, 01:01

Tritium_James wrote: We have a nice little copper-rotor 7.5kW 4-pole 132 frame motor from SEW Eurodrive, that is rated 100V line-line, as a standard off-the-shelf item. That's a standard voltage in Japan or somewhere similar.

According to this Wikipedia page, there are two countries in the world where the mains is 100 V nominal. That's 100, not 110 or 115/117/120, a bare 100 volts. How do they get driers and ovens to work on that low voltage, I wonder?

The two countries are Japan, and Okinawa, a perfecture of Japan (just north of Japan). North America has 120 V mains, and they get around the problem of high power appliances with their split phase system, where they have 240 V with a centre tap, and that centre tap is their neutral. So high power appliances have 240 V available, and general usage items use 120 V.

But this split phase system seems to be largely confined to North America. Other countries with 120 V mains possibly use another phase from a 3-phase transformer, resulting in 208 VAC (half of our 415 V phase to phase voltage). The equivalent in Japan would be another phase from a 3-phase transformer, resulting in about 173 V phase to phase, which they round to 175 V. (Or perhaps their mains is actually 101 V, and they round that down to 100 V).

So assuming that Japanese (and Okinawan) homes and businesses mainly have 100 V single phase or 175 V three phase available, their induction motors would presumably be wound for 175 V. If these are wired in star for 175 V, then they would be 100 V if connected in delta. (I imagine it would be more common to see 175 V delta, and 303 V if wired in star, just as most of our 415 V motors are 415 V in delta, and 720 V if wired in star.)

Just imagine: the motor that pulled your Japanese car along the production line was probably running at just 175 V!

So if you're dealing with a motor supplier and they tell you that 220 V is the lowest standard voltage, you could ask them to check their Japanese office. They should have 175 V and possibly even 100 V motors available for that presumably quite significant market.

Oops, just done some last minute research, and it looks like Japan might have a split-phase system after all. For example, this motor:

Image

would appear to indicate that Japanese 3-phase is 200 V, so their 100 V outlets are presumably from a centre tap, a la North America.

Does anyone know?
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