75-5 & 75-7 Motors - Looking for Test Engineers

methods

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Hello,

This post is borderline Marketplace but before we talk about sales I would like to talk about field testing.

We have in our possession a handful of modified 75-5 and 75-7 motors that have been paired with a Sevcon Gen 4 and a custom crimped wiring harness.

View attachment 5

Some motors have a complete carbon wrap and some are a hybrid of steel band and carbon wrap. We have a screening process that runs the motors up to a fixed RPM while monitoring temperature and power. To pass, this particular batch of motors have run for 20 minutes at 5500 RPM with temps hitting 110C to 120C. This is as much confidence as we can build in the lab so we would like to put 10 out in the wild to get some validation data.

I have been avoiding unnecessary destructive testing... but some of the tests have been up to 6,200 RPM for extended periods at high temp. The relationship between force on the carbon wrap and RPM can be described by this formula:

RCF (or G-force) = 1.12 x R x (RPM/1000)²

Note that there is a squaring of RPM so that should tell you that the difference between 5000RPM and 6000RPM can be considerable. Below is some data based on the above formula.

forceVSrpm.jpg

If these calculations are correct (somebody peer check please) then that tells us that to run at 6000RPM instead of 5000RPM we experience a 50% increase in force!!! That's considerable... and plays heavily into our methodology for assessing margin and reliability. Its not possible or representative to just "over-test" the motors to some arbitrarily high RPM as it will result in D-Test (Destruction). Instead reliability is assessed by burning in at a margin RPM for a period of time that allows thermal equilibrium to be achieved.

CarbonWrap75_7_006.jpg
CarbonWrap75_7_007.jpg
CarbonWrap75_7_008.jpg

All that is great - I trust the data. :D Thats how we do it with a lot of aerospace stuff that we cant just launch into space willy-nilly....

Whats better is FIELD DATA.... :shock:
oooooooohhhhhh.... :mrgreen: :mrgreen: :mrgreen:

Something we rarely got to work with at the National Lab.

So... We are looking for some candidates who want to act on an opportunity to get some very nice motors paired to some very nice controllers with a custom firmware flash and (Not to Exceed XYZ) engineering support from yours truly.

This isn't a blowout sale so please be ready to pay market on the parts. This is a value-add run where we are offering to get your project up and running (don't underestimate the difficulties...) in return for some basic run-time data. We are interested in the following applications:

* Marine applications - sail boats, out-runner conversions, custom rigs (but beware the corrosion!)
* Road applications - Tadpoles, light EV's, solar cars, student projects, karts, you name it
* Air applications - Anything that can glide
* Generation applications - Wind mills, hydro electric, regenerative, etc.
* Nerd applications - Hey... if you want to just tinker with the system and report back that's fine too.

Lets let this be an open space to speak of the technical ins and outs of what the motors are capable of, what applications are appropriate, etc.

On site here we have a Dyno that should be capable of up to 50hp. We are testing at 24V, 48V, and >96V. Current levels from 10A to >400A

DYNO_001.jpg
DYNO_005.jpg


If you are interested start sounding off in this thread and lets talk about how we can get the ball rolling with some really interesting projects. If you have any data on your load profile we can start by running those numbers here to get an idea of how good the match is.

* Continuous and peak RPM
* Torque/Thrust
* Load profile (load vs time)
* Cooling availability (thermal mass, airflow, liquid)
* Available Power (48V, 96V...), chemistry (lead or lithium), capacity etc (so we can profile in sag under load, max current, continuous current, run time,...)

-methods
 
I seek a configuration that can beat Luke at the dragstrip. :mrgreen:

I wish I was able to exploit your services, Sir. Perhaps sometime in the future when I'm better funded.
 
That should be easy enough to accomplish...
DeathBike was kind of weak. I rode it in the dark with no lights on a wet road with sketchy gear and it only went ... uh... well... it only went 1/3 throttle and I could never get past that :mrgreen:

We just completed some tests at >6000rpm and temps hovering at 120C. That's a pretty harsh test. We are still playing with different epoxies. They can get pretty expensive at the high end and I dont think we need to blast off into outer space where we may see 220C. I'm trying to inch into the D-Testing so as not to create unnecessary waste. So far I have only been able to kill the Dyno - and that was pure user error as I ran it backwards :shock:

-methods
 
Oh my, that would be the perfect package for a fun little moped build. Would you be interested in me using this package in a moped like this?

What is the weight of motor and controller?
Do you have a approximate price tag?
Since you are after user data, I guess you want to get the data fairly soon? Any deadline for project completion?
 

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My Ducati is waiting for a new motor ;) ...
 
Wow! it seems to me as an outstanding piece of work. But please let me ask one fundamental question? What is your primary goal to achieve with this Zero motors modifications?

My first idea was that with CFRP wrap you would like to achieve higher rotor speeds than 6000rpm? Did you make some modification of the rotor geometry/magnets as well? The stator remain unchanged default from Zero?
 
Ratking said:
Oh my, that would be the perfect package for a fun little moped build. Would you be interested in me using this package in a moped like this?

Interested in all DIY applications

What is the weight of motor and controller?
Do you have a approximate price tag?
Since you are after user data, I guess you want to get the data fairly soon? Any deadline for project completion?

I can put out some weight numbers later - fiddling with load testing now. :twisted:
As for as price - lets leave that for the sales thread.
We are interested in collecting as much data as we can and sooner is better.


-methods
 
Jozzer said:
My Ducati is waiting for a new motor ;) ...


I'm working on it.... You said 10,000RPM and 100hp right?
How about two pcs 50hp and then you can gear it like its 10,000 RPM???

-methods
 
Martin A said:
What are the dimensions of the motor and controller. I'm looking at building an Aprilia Magnet http://www.gizmag.com/go/3629/ inspired trike.

Let me get back to you on that at the same time we talk about weight.

-methods
 
This is a different venture and these motors carry none of those trade markings.
Lets not bring that company into any of these discussions if possible. :)

We can talk offline if you want. Basically we need to focus on DIY extreme R&D activities here.

thanks
-methods




Pajda said:
Wow! it seems to me as an outstanding piece of work. But please let me ask one fundamental question? What is your primary goal to achieve with this Zero motors modifications?

My first idea was that with CFRP wrap you would like to achieve higher rotor speeds than 6000rpm? Did you make some modification of the rotor geometry/magnets as well? The stator remain unchanged default from Zero?
 
Now for an update:

I have been trying to get some good dyno data going. The dyno was half built when I started. So far (as I start to get up over 10hp) I have had to add a large heat-sink to the drive Sevcon and its time to straighten out the chain line and get more tooth engagement. These motors are stupid powerful... easy to underestimate. When I start to load the system up I can first spin the teeth right off the belt (Blowing blue dust everywhere :mrgreen: ) and then I was able to yank the adjustment bolt (1/2") right out of the tensioner.

These are good things...

So... I think we are going to spread the motors further apart and make them adjustable. Its pretty gnarly sitting 2' from this thing when it starts cranking under load :shock:

-methods
 
Good to see you back in the hunt Captain Sparky! I too was amazed at that wee little belt in your dyno pix.

Have you thought about in line connection with a elastomer or double row chain coupling?
 
bigmoose said:
Good to see you back in the hunt Captain Sparky!

What would really be interesting would be if you were to explain to us what you would hope to find in people you were to work with. . . .

methods said:
Hello,

This post is borderline Marketplace but before we talk about sales I would like to talk about field testing.

If these calculations are correct (somebody peer check please) . . . .

So... We are looking for some candidates who want to act on an opportunity to get some very nice motors paired to some very nice controllers with a custom firmware flash and (Not to Exceed XYZ) engineering support from yours truly.
This is a value-add run where we are offering to get your project up and running (don't underestimate the difficulties...) in return for some basic run-time data.

If you are interested start sounding off in this thread and lets talk about how we can get the ball rolling with some really interesting projects.
-methods
 
Dauntless said:
What would really be interesting would be if you were to explain to us what you would hope to find in people you were to work with. . . .


That's not how he works lol.
 
These sound like just the thing I need for my next dog/cargo-hauling trike. One on each wheel geared down nice and low should about do it, then I can haul entire buses full of St Bernards up mountains. :)
 
Currently have a R6 with a Size6 and 75-7 motor. The motor has been modified to operate as a 6 phase motor in the future with the addition of a size4 controller. 28s of 2012 Nissan Leaf cells.

6000 RPM =110mph, usually cruise at 75 (-4100RPM) for 10-20minutes. Can really do any profile to test. Bike uses 10kW at 75mph, like 6kW at 60mph. Can do full current for 4-5sec before I'm over 80mph. I've pulled 63kW from the battery multiple times before. Currently have a sevcon clearview display to monitor motor temp. CA can DAQ the battery and vehicle, but don't have a good way to get motor data at the moment.

I wouldn't want a new motor, but I'd be willing to swap the rotor for the potential to get more RPM (7000RPM+). I assume these are SPM rotors?


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Sent from my iPhone using Tapatalk
 
Methods,

I am just wondering what is the main ghoal of these tests? From what i know , Ryan, the designer of that motor already tested these alot in the field and races.
For the Zero industry these are rated 16kW continuous for the 75-7 and this is from what i learned, a continuous power at witch the motor or the controller dont raise temp more than 1 degre C over a period of 2 hours.

I already have 3 of these: the 2012 hybrid 75-7 4 turns, the 2013 regular 75-7 and the new IPM 75-7R 2016. I will play with them over the next weeks/months.

i am really curious to these the 4 turn version on my dual size 6 (with split phase 75-7) and fid the limit in term of torque.

Actualy Arlo got nice numbers with 81hp using dual size 4.

I did not know that the 75-X motor also existed in carbon wrap rotor version.. that's interesting

Doc
 
Doctorbass said:
Actualy Arlo got nice numbers with 81hp using dual size 4.

Doc
My record is 87 ;) and that's rwhp! Over 90hp at the motor with 2 size 4s
 
Arlo1 said:
Doctorbass said:
Actualy Arlo got nice numbers with 81hp using dual size 4.

Doc
My record is 87 ;) and that's rwhp! Over 90hp at the motor with 2 size 4s


Arlo are you using 2x ZF3.3 modules for the 87hp at the Wheel? or more modules?

Doc
 
Doctorbass said:
Arlo1 said:
Doctorbass said:
Actualy Arlo got nice numbers with 81hp using dual size 4.

Doc
My record is 87 ;) and that's rwhp! Over 90hp at the motor with 2 size 4s


Arlo are you using 2x ZF3.3 modules for the 87hp at the Wheel?
Doc

I had lots of batteries. But Nothing to mount on the bike. The reason for this is I wanted to show how using really high C rated cells will make more power.

And yes rwhp Its accurate with NO corrections on the dyno
 
Doc[/quote]

I had lots of batteries. But Nothing to mount on the bike. The reason for this is I wanted to show how using really high C rated cells will make more power.[/quote]


Yeah that is straight in light with my drag bike project and the 13 pounds 70kW battery :twisted:

Doc
 
bigmoose said:
Good to see you back in the hunt Captain Sparky! I too was amazed at that wee little belt in your dyno pix.

Have you thought about in line connection with a elastomer or double row chain coupling?


Hey Big Moose

We have not talked since you gave me resume advice... never got around to thanking you for that.

Turns out the slipping belt was my mistake. This is actually a good one to share:

So... in DVT there is a test window that will write to the RPDO's

DYNO_002.jpg

If you press the Setup button it will write your RPDO1 with FS1, Forward, and Throttle

DYNO_001.jpg

This allows you to run the motor pragmatically - which is useful... unless you have more than one Sevcon on your network :evil:

It appears at first that the node selection box should have an effect on this tool BUT IT DOES NOT. I have found that the Test Box will speak to both node 1 and node 2 :| :| :|
Very irritating.
Anyway... I was unintentionally instructing the motors to fight... and they were doing so... and the belt was in the middle.

-methods
 
amberwolf said:
These sound like just the thing I need for my next dog/cargo-hauling trike. One on each wheel geared down nice and low should about do it, then I can haul entire buses full of St Bernards up mountains. :)

I like how you are thinking. 100hp is about what I was thinking a standard bike trailer would need. Most of them are rated for 2pcs 50lb kid... so 1hp/lb sounds like a good power to weight ratio.

-methods
 
Nuts&Volts said:
Currently have a R6 with a Size6 and 75-7 motor....

6000 RPM =110mph, usually cruise at 75 (-4100RPM) for 10-20minutes. Can really do any profile to test....

... potential to get more RPM (7000RPM+). I assume these are SPM rotors?


This sounds like a good stress test platform. What temperature do you allow your motors to get up to?
Care to share more about your 6 phase learnings? Yesterday we talked seriously about mounting two of these motors together in series. The mechanics are straight forward but the drive configurations is not an area where I am already familiar.

As far as additional RPM... my understanding is that the BEMF and thermal dump make it a diminishing returns deal... but... I like my stuff to be able to rev up past the point of sanity. I was just watching the new process and we have made some discoveries that I think may result in the ability to reach higher RPM should you want to. I can say for certain that I am going to test at least one representative motor up to its limit to understand our margin. It is my understanding that the carbon stretches much less than the standard steel bands... so my guess is that we will be able to push it a long way before it fails. We were just discussing how much extra thickness we could add without running into laminations worst case.

These are the motors that have the magnets surface mounted.

-methods
 
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