Clueless take 2

Post by **T1 Terry** » Wed, 17 Nov 2010, 15:34

Richo wrote: In any case it will probably work out cheaper and easier to have a 3-phase motor setup to ~140Vac in delta mode.
So it won't really matter which size you pick because it is a custom job any way.
I would expect any self respecting rewinder could do this job for you.

This sets you pack for around 340Vdc.
Which simplifies the conversion from the traction pack through 12V bus battery to the 240Vac inverter to supply appliances.

If the motor is being rewound anyway could I get it rewound for even lower voltage so the battery pack could be a lower voltage?

T1 Terry

Post by **Johny** » Wed, 17 Nov 2010, 15:54

You have to be a bit careful here. The lower the motor voltage, the higher the current will be. High current controllers get big and expensive. The controller is easily the most important part of an AC EV.

Richo has a good point is also choosing a voltage that makes adding peripherals easy. 240 VAC mains devices that use switching power supplies tend to run off 340 VDC pretty easily. It makes heaters, DC-DC (for the 12 VDC system) easier and cheaper. It also opens up hacking a 12VDC to 240 VAC inverter to directly feed it's internal 340 VDC Bus possible. (The result is a high efficiency 240 VAC power source on board - lots of possibilities).

You also have to carefully choose the point at which your motor goes into constant power mode and the torque starts to reduce. That dictates your motor rewind voltage. I chose just under 80km/h. If I raised that speed then I would need higher current to get reasonable performance at lower speeds. The voltage I used was dictated by the controller(s) I had already purchased.

It's all less of a balancing act if your controller is capable of very high current.

Edit: Sorry Richo and woody - I just re-read this thread and realised you have covered these points already. Oh well, another take on it.

Post by **Catavolt** » Wed, 17 Nov 2010, 17:37

I live in Newcastle I can check the motors out for you.

Also I recently sold a 11kw 4p 132 frame wound to 100v with bearing encoder for a Smart car, $1750.00

Post by **T1 Terry** » Wed, 17 Nov 2010, 20:11

Thanks Jonny and Catavolt,
I'm back with the program now, the 100v motor wind and 340v battery pack is the best combination cost wise for my particular application, is that correct?
Thanks for the idea on price Catavolt and the offer to check out the motors, once I've priced it all up and checked the piggy bank to see if going ahead is financially viable I will take you upon your kind offer.
What type of controller am I going to need for this project? The jolt mentioned on other posts of a Curtis controller isn’t going to be an issue in this application or have I cross confused different types of controllers here?
Now to find out what a LiFeP04 battery pack is going to cost, this will test the sphincter muscles

T1 Terry

Post by **Johny** » Wed, 17 Nov 2010, 20:18

T1 Terry wrote: Thanks Jonny and Catavolt,
I'm back with the program now, the 100v motor wind and 340v battery pack is the best combination cost wise for my particular application, is that correct?

Have I missed some details?
What peak power at what RPM do you want?
Is the motor effectively coupled to the drive shaft so no varying gear ratios possible?

Post by **T1 Terry** » Wed, 17 Nov 2010, 20:37

The motor will effectively coupled to the ICE so operating range will be from 1,000rpm to 4,500rpm. The motor speed will be between 0 rpm and 4,500rpm, most like the regen will be more between 4,500max and 1,500 min and the assist between 1,500 and 2,500rpm.
Coupling it direct to the tailshaft could be another option, then both ranges would be between 0 rpm and an absolute max of 3,500rpm but I doubt I have hairy enough palms to pilot the thing at the upper rpm's, that's up around 130km/h.

T1 Terry

Post by **Richo** » Wed, 17 Nov 2010, 20:38

Catavolt wrote:Also I recently sold a 11kw 4p 132 frame wound to 100v with bearing encoder for a Smart car, $1750.00

Any chance of a link somewhere on this one?

Sorry off topic

Post by **Johny** » Wed, 17 Nov 2010, 21:05

T1 Terry wrote:....and the assist between 1,500 and 2,500rpm.

OK. You should get plenty of regen pretty much whatever reasonable motor power you end up with - normally it has to be dialed back a bit.

The big question now is how much assist power would you like?
More importantly, at what motor RPM do you want peak torque - 2500 RPM?

Another big question. What is the budget for the controller? The Curtis is a kind of toy compared with what you want to do. Your motor peak torque will indicate the correct peak current for the controller.

Post by **Catavolt** » Wed, 17 Nov 2010, 21:11

No links on the smart project yet.
You can contact user "ibruinsma" its his car I just supplied the motor.
I normally rewind induction motors to work with the Curtis AC controllers or industrial VSD but this 132m frame motor is to work with the Tritium controller .

Post by **T1 Terry** » Wed, 17 Nov 2010, 22:06

Johny wrote:
T1 Terry wrote:....and the assist between 1,500 and 2,500rpm.
OK. You should get plenty of regen pretty much whatever reasonable motor power you end up with - normally it has to be dialed back a bit.

The big question now is how much assist power would you like?
More importantly, at what motor RPM do you want peak torque - 2500 RPM?

Another big question. What is the budget for the controller? The Curtis is a kind of toy compared with what you want to do. Your motor peak torque will indicate the correct peak current for the controller.

When was there ever too much

this will be what ever I can get keeping the motor weight/cost and battery cost and controller cost within a budget. If it's ICE coupled 20kw to 50 kw would be great but if tailshaft coupled it would need to be up around the 50kw. The peak torque would need to be down around 1,500rpm if ICE coupled and down the 0 rpm end if tailshaft coupled.
What is the price of a Curtis controller, if it's not going to do the job then that's not really relevant I guess. I checked out the price of the Wave Sculptor 200

Is that sort of a top figure or.....

T1 Terry

Post by **Johny** » Wed, 17 Nov 2010, 22:20

The Wave Sculptor 200 is a fantastic controller and would be perfect for you but it is on the dear side (for you, not generally) because it is so compact. Unless I am mistaken you could accommodate a physically rather large controller but it will be difficult to find one in the power range you want that runs from 340 VDC.
Most 40-50kW VFDs run off 600-700VDC.
However, many of them will happily run down to 250 VDC - I have a feeling that Weber and Coulombs for-sale controller will but it's the same price as WaveSculptor.

I was going to point you at Spark Bros controller but:
1/ It's 400V x 3 phase which makes it 650 VDC
2/ He has removed the guts from all the posts on that for sale topic.

Industrial VFDs come up every now and then but the 50kW range is not as common.

Post by **antiscab** » Wed, 17 Nov 2010, 22:47

This AC Kit is based around the largest curtis controller.

put it ICE coupled, and it should be useful.

Matt

Post by **T1 Terry** » Thu, 18 Nov 2010, 00:36

Thank Matt,
I checked out that Curtis controller on another site and the 550amp is a 2 min rating. What happens after the 2 mins, does the smoke come out? are there water cooled options with these controllers or are we now heading into the top shelf stuff? I did like the idea of the 108v battery pack though and the regen and the price was a little less breath taking.

T1 Terry

Post by **antiscab** » Thu, 18 Nov 2010, 00:54

if that controller is well designed, than after 2 minutes, power drops off.

Those AC controllers are much more recent in design than the horrible 1231C.

watercooling the base plate would improve that, though build it first to see how it goes

Matt

Post by **EV2Go** » Thu, 18 Nov 2010, 04:54

The 1231C is an excellent size for a wheel chock...

Any chance of a picture or diagram of the proposed motor / engine arrangement?

Was just thinking when the motor isn't powered it doesn't consume a great deal of power (mechanical I mean) perhaps there may be a way to put the motor between the engine and the diff instead of a PTO arrangement???

Edit:
Sorry slightly off topic but...

plus

Would make a nice little AC Mini conversion

Post by **Catavolt** » Thu, 18 Nov 2010, 15:43

Post by **Catavolt** » Thu, 18 Nov 2010, 15:43

NHP do a 130amp AC drive 180-400vdc $4-5k 22kw cont 33kw 1min peak 44kw 30secs 6 weeks delivery from any electrical wholesaler .

I have more data if any wants it.

Post by **T1 Terry** » Sun, 21 Nov 2010, 00:22

The kit Matt pointed me to has a Curtis controller and a HPGC AC50-01 Motor, 52 hp Peak @ 96 volts, 60 hp peak @ 108 volts and judging by the torque chart up around the 550amp mark to get the 60hp. What batteries am I looking for with that sort of discharge capability. The ones I’ve looked at so far seem to be rated at 2C for a 100ah battery. Do I need to run 3 sets in parallel to get the required discharge current or am I missing some thing as usual?

T1 Terry

Post by **antiscab** » Sun, 21 Nov 2010, 02:28

TS/SE will do 3C for 30 sec, and more like 1C continuously.

34 x 200Ah cells would do.

you can do smaller higher rate cells, put the cost will be the same for the same energy capacity.

Matt

Post by **T1 Terry** » Tue, 08 Feb 2011, 00:43

OK, after reading some in the DIY forum I have discovered that the 550amps may not be battery draw but amps supply from the controller (remember the title says I'm clueless) so how do i find out what the battery amp draw max would be?
The next bit is related to battery voltage, the Curtis Model 1238R controller says it’s suited for 72v to 96v systems, does that mean I'm restricted to running a max battery pack voltage of 96v?

T1 Terry

Post by **antiscab** » Tue, 08 Feb 2011, 01:44

thats the nominal voltage range for lead acid packs.

the controller allegedly still works up till 130v (max).

Matt

Post by **coulomb** » Tue, 08 Feb 2011, 13:55

Yes, there are people using 35 and I think even 36 LiFe cells with this controller. There is also a 650 A RMS output version in the last week or so. And a 144 V nominal version this year some time.

Post by **T1 Terry** » Thu, 10 Feb 2011, 14:49

The kit Matt pointed out in an earlier post uses a HPGC AC50-01, does anyone know how long one of these motors can handle full load before they overheat? The other monster motor on another thread looked the goods until the weight was announced, 220kg is a tad over the top.

Also, there is the new higher output controller from Curtis that coulomb mentioned, would I be better to go for one of these? Would they have a longer 500amp rating than the 2 mins the 1238-7501 controller has?

What if I went to a DC motor and used a Kelly controller for the progressive regen? The operating range I need the torque is from 1,500rpm up and peak rpm would be 4,500max, could I get a 50kw peak DC motor with good bottom end torque or is this restricted to the AC world?

T1 Terry

Post by **Johny** » Thu, 10 Feb 2011, 14:57

T1 Terry wrote: The kit Matt pointed out in an earlier post uses a HPGC AC50-01, does anyone know how long one of these motors can handle full load before they overheat?

The website indicates:
"One HPGC AC50-01 Motor, 52 hp Peak @ 96 volts, 60 hp peak @ 108 volts, 15 hp continuous, 6500 RPM"

So they appear to suggest 15 HP continuous at 6500 RPM.

Post by **T1 Terry** » Thu, 10 Feb 2011, 15:58

How long is the run time for peak power? The controller says it can handle 2 mins @ 550amps but no mention as to how long the motor can handle it. My plan is to use the addition torque/HP for hill climbing but mostly for regen braking. I assuming the motor and controller are copping it equally as hard on the pull as in regen so peak run time counts as far as motor/controller section. Keep in mind I'm trying to slow 10 tonne down hill.

T1 Terry