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Discussion Starter #1 (Edited)
Hey Guys!

I am part of a multidisciplinary technical/non-technical club within a university (SFU) near Vancouver BC, and our team's goal is to compete within a competition that SAE puts on. Team's all over North America participate, and this will be our first appearance on the track in Summer 2019.

Other than passing an assortment of technical inspections, we have to complete a 75 meter acceleration test, and a 20 lap (20 km) endurance test as well. Ideally we would like the slickest motor out there, but as this being our first competition we want to be able to make it through the inspections
(as a vast amount of teams do not) and participate in the racing events.

Our current problem is finding an appropriate 300V motor on a budget. Our ideal motor/controller combination is the Emrax 228 MV paired with the Bamocar D3, but this is much to expensive for us. No type of motor is off the table, obviously being reasonable though.

So, I would really appreciate help on finding motors that operate at 300V. Our Formula car will roughly be around 300kg, 3m in length and roughly 1.5/2m wide. We are trying to minimize footprint and weight by the motor. The rules say our max power output by the motor is 80 kW or less.

I understand these are quite vague parameters, but motor brand suggestions and motors them selves would be greatly appreciated. As I said above the emrax and bamocar are our ideal solutions.

http://emrax.com/products/emrax-228/

http://www.mankeit.com/pdfs/E-BAMOCAR-D3.pdf

Cheers!
 

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Discussion Starter #3
Interesting suggestion (how he thinks at 300V it would produce 100kW), do you know where the people within the blog are picking these up?
 

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The Motenergy ME1616 is rated at 55 kW peak and according to the website is available in various voltages. Standard specification is 96V and it can be bought for around $1200. It weighs twice as much as the Emrax motor and is about twice the size, but it is water-cooled. The company answers emails quickly in my experience.

Is the 300V requirement part of the SAE rules?

Malcolm
 

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Discussion Starter #6
The 300V is not a requirement, but we got a sponsored IMD from bender that was programed for a 300V system. So we are trying to find motors that operate at 300V before we jump ship and ask bender if they will re-program the unit.
 

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Keep in mind you don't actually want a 300V system. 300V is your absolute peak voltage per the rules. You'll want some headroom in there.

Are y'all a first year team overall, or just first year electric? 300kg is really heavy unless that includes driver...Even then, that's heavy.

A few teams have used salvage motors from a Tahoe Hybrid transmission, which has two Remy HVH 250's in it. Rinehart makes a suitable controller.

You might look at buying a Zero motorcycle setup or maybe even whole used bike, as well.
 

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A few teams have used salvage motors from a Tahoe Hybrid transmission, which has two Remy HVH 250's in it. Rinehart makes a suitable controller.
A salvaged motor makes sense to me, especially for a low budget. Availability of a matching and usable (outside of the original car) controller is important, so that's great tip. I assume Rinehart offers this controller because the HVH 250 is available to other buyers (not just the auto manufacturers), unlike most production EV and hybrid motors.

Using the HVH motor without the Two-Mode Hybrid transmission case means making a housing for it... maybe a good project challenge.
 

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Discussion Starter #9
Keep in mind you don't actually want a 300V system. 300V is your absolute peak voltage per the rules. You'll want some headroom in there.

Are y'all a first year team overall, or just first year electric? 300kg is really heavy unless that includes driver...Even then, that's heavy.

A few teams have used salvage motors from a Tahoe Hybrid transmission, which has two Remy HVH 250's in it. Rinehart makes a suitable controller.

You might look at buying a Zero motorcycle setup or maybe even whole used bike, as well.
Yea we are a first year team! And on the note about weight, I recorded 18 school spec's given and there all within the 250kg - 300kg range (roughly), what school did you compete with?

And Nice that Remy motor is quite impressive! did you guys use that combination?

Yea, I called Zero to see if they would sell there motor/controller separately and what not but just got a flat no.
 

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Where'd you get the weight information? The program event guide often lists weight with driver if that's your source. I'm not saying go crazy trying to optimize, but you should be shooting for under 230kg. That said, as a first year team, your priority should be to pass tech and compete in all events. At Lincoln, that will get you a top 5 finish. Keep it as simple as it can possibly be.

The Remy is a good motor, but heavy. GFR ran it in one of their first e-cars. As far as Zero goes, a full bike isn't a bad way to go. There's a 2015 Zero DS ZF12.5 in Austin, TX for $7500 for example. Compared to other systems, that's not bad. The Rinehart for the Remy is something like $4500 alone and then you've got to find and buy the motor.

Thaaat said, and I might be ridiculed some for it, but I would even go as far as using a brushed system for a first year team. Series wound golf cart motors are plentiful, cheap, there are tons of controller options, and they can be over-volted quite a bit. Less wiring, less tuning, easier setup, waaay cheap.

I was on Texas A&M's Hybrid team in '11 on the motor team, then our FSAE team in '12.
 

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Thaaat said, and I might be ridiculed some for it, but I would even go as far as using a brushed system for a first year team. Series wound golf cart motors are plentiful, cheap, there are tons of controller options, and they can be over-volted quite a bit. Less wiring, less tuning, easier setup, waaay cheap.
I see the logic there - there are many aspects to a car, and no team creates sophisticated solutions for all of them from scratch in a single year; you could put together a suitable chassis which packages the electric powertrain components first, then upgrade various components in subsequent years. A challenge with this approach is the interdependence of all components: a low-voltage battery feeding a DC controller for a brushed motor means that none of the parts are usable as-is in system using modern technology (higher voltage AC). The motor's physical format determines mounting options, and its operating speed range determines gearing (and gearing ratio determines mechanical drive options). Of course if you shoot for just under 300 volts even with a brushed DC motor, the battery would be compatible with a different controller and motor later; you could leave a big space for the motor, and connect it to the final drive with a two-stage chain drive, for motor (size and speed) flexibility.

As with any design exercise, the first step should be to establish goals and requirements, then chose a solution to address those. Is the point to learn about advanced electric drive systems, or to make a quick car, or what?
 

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A challenge with this approach is the interdependence of all components: a low-voltage battery feeding a DC controller for a brushed motor means that none of the parts are usable as-is in system using modern technology (higher voltage AC). The motor's physical format determines mounting options, and its operating speed range determines gearing (and gearing ratio determines mechanical drive options). Of course if you shoot for just under 300 volts even with a brushed DC motor, the battery would be compatible with a different controller and motor later; you could leave a big space for the motor, and connect it to the final drive with a two-stage chain drive, for motor (size and speed) flexibility.
I definitely see the value in this, but I'm not sure I would push for that in a first year team. I would think (having never been in the situation), that documenting the process, scheduling, competition planning, competition itself, budgeting, etc...would be more valuable than attempting to make the design scale. I dunno...I guess to me, the tough part of a custom solution would be characterizing the motor and tuning. I just see a team getting stuck on motor tuning and not being able to finish the car. Buying a package makes it as simple as mounting and wiring. If you can afford it, then a 300V package makes a lot of sense for the reasons you've stated.

As with any design exercise, the first step should be to establish goals and requirements, then chose a solution to address those. Is the point to learn about advanced electric drive systems, or to make a quick car, or what?
Long one coming up that only kind of replies to you, ha.

That's a very interesting question. Motivation varies greatly. FSAE at A&M is a capstone design project. Back when I did it, the official goal of the program was to teach the engineering design process and implement it in a pseudo real-world project. Unofficially, we just wanted to win. I firmly believe that making winning the goal means everything else will follow. You learn what you need to learn, or you won't have the knowledge required to win.

The competition is structured so that in order to win, a team must do well in Static and Dynamic events. A team can place in the top 10 with poor Static results, but it is unlikely they'd win. That means the design process, from need statement and initial concepts to detail design, needs to be clearly documented and presented if a team wants to have any chance of winning...It should be obvious, but that means knowing and actually using the design process for decision making. A lot of teams, especially newer ones, don't do this.

Along with that, in the end, the winner is the team with the most combined Static and Dynamic event points. Therefore, the goal of any team (assuming they are trying to win or place well) is to score as many points as possible. Tying every decision made back to points gained or lost is a great way to justify designs. Does this gain or lose points? If it loses points, there needs to be justification for it based on other factors.

Now, all of that is more suitable to well established teams, but the concept still applies...Make goals and always justify how designs help accomplish them. For these guys, maybe their need statement should say that they must pass tech and compete in all the events. Passing tech and competing means a complete, functional car is needed. If a concept significantly complicates passing tech over another or requires significantly more design or manufacturing time, then it probably shouldn't be picked. There should be a schedule laid out specifying a hard deadline on having the car on the ground and running, ideally at least a month prior to competition. Working backwards from that, a hard deadline on completion of designs. If a concept isn't able to be completed by that deadline, it gets the ax.
 

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Figured to toss in a quick $.02. From my experience on SAE Baja, and having shared shop space with the FSAE guys... adhering to all of the small detail rules regarding safety and chassis design - simply getting a working car together for competition that passes all inspections is a staggering accomplishment for a new team. That being said, a new team will likely not want to go bleeding edge on technology from an electric drives standpoint

Someone mentioned earlier the ME1616 motor, which is the liquid cooled version of the ME1507 - either of those motors would get the job done - and going someone mid range on voltage 100-150V will keep costs of controller and BMS reasonable if budget is a major constraint. A person could expect 40-50hp out of a ~120V ME1507
 

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Figured to toss in a quick $.02. From my experience on SAE Baja, and having shared shop space with the FSAE guys... adhering to all of the small detail rules regarding safety and chassis design - simply getting a working car together for competition that passes all inspections is a staggering accomplishment for a new team. That being said, a new team will likely not want to go bleeding edge on technology from an electric drives standpoint

Someone mentioned earlier the ME1616 motor, which is the liquid cooled version of the ME1507 - either of those motors would get the job done - and going someone mid range on voltage 100-150V will keep costs of controller and BMS reasonable if budget is a major constraint. A person could expect 40-50hp out of a ~120V ME1507

You may also try contacting the manufacturer of the ME1616, Motenergy, and seeing if they could get you a custom wound version for either a higher voltage or dual 3phase system. More complex, but still a cheap option give you more power. Or just run two of them with two size6 sevcons.

Look up and PM Frodus on these forums. He can get you a good deal on controllers/motors




Sent from my iPhone using Tapatalk
 

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Discussion Starter #15 (Edited)
Where'd you get the weight information? The program event guide often lists weight with driver if that's your source. I'm not saying go crazy trying to optimize, but you should be shooting for under 230kg. That said, as a first year team, your priority should be to pass tech and compete in all events. At Lincoln, that will get you a top 5 finish. Keep it as simple as it can possibly be.
Okay great thanks for the bench mark, passed that on to the chassis guys!

Thaaat said, and I might be ridiculed some for it, but I would even go as far as using a brushed system for a first year team. Series wound golf cart motors are plentiful, cheap, there are tons of controller options, and they can be over-volted quite a bit. Less wiring, less tuning, easier setup, waaay cheap.


I was on Texas A&M's Hybrid team in '11 on the motor team, then our FSAE team in '12.

Texas A&M, I bet your facility was unreal!

I definitely see the value in this, but I'm not sure I would push for that in a first year team. I would think (having never been in the situation), that documenting the process, scheduling, competition planning, competition itself, budgeting, etc...would be more valuable than attempting to make the design scale. I dunno...I guess to me, the tough part of a custom solution would be characterizing the motor and tuning. I just see a team getting stuck on motor tuning and not being able to finish the car. Buying a package makes it as simple as mounting and wiring. If you can afford it, then a 300V package makes a lot of sense for the reasons you've stated.
Yea it's interesting, It seems that motor tuning is quite the challenge, something that I did not consider. I am doing my own EV conversion, and once you have the concept down a EV isn't overly complex (moving parts and what not) compared to a internal combustion engine (i know someone is going to call me out on this..)

Figured to toss in a quick $.02. From my experience on SAE Baja, and having shared shop space with the FSAE guys... adhering to all of the small detail rules regarding safety and chassis design - simply getting a working car together for competition that passes all inspections is a staggering accomplishment for a new team. That being said, a new team will likely not want to go bleeding edge on technology from an electric drives standpoint

Someone mentioned earlier the ME1616 motor, which is the liquid cooled version of the ME1507 - either of those motors would get the job done - and going someone mid range on voltage 100-150V will keep costs of controller and BMS reasonable if budget is a major constraint. A person could expect 40-50hp out of a ~120V ME1507
The bleeding edge for us is out of the question mainly because of budget, we are a new team with very little money. Starting from the bottom in regards to that.

I'll look more into those motors. I'm hesitant (too a point) to drop below 300V because we order our bender with 300V in mind, so sending it back I'm not sure how pleased they will be, but at the end of the day it is what it is.
 

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Discussion Starter #16
What's your guys opinion on Hub motors, and controlling them. We might have the ability to get two hub motors for extremely cheap. The spec's of these motors I don't know off the top of my head, but someone has figured they are suitable.
 

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Texas A&M, I bet your facility was unreal!

Yea it's interesting, It seems that motor tuning is quite the challenge, something that I did not consider. I am doing my own EV conversion, and once you have the concept down a EV isn't overly complex (moving parts and what not) compared to a internal combustion engine (i know someone is going to call me out on this..)

The bleeding edge for us is out of the question mainly because of budget, we are a new team with very little money. Starting from the bottom in regards to that.

I'll look more into those motors. I'm hesitant (too a point) to drop below 300V because we order our bender with 300V in mind, so sending it back I'm not sure how pleased they will be, but at the end of the day it is what it is.
You'd be surprised. Our shop was in the oldest operating lab building on campus and generally run down. We had everything we needed between that and the MEEN machine shop and we were thankful for what we had, but none of it was anything super special.

EV's are certainly easier from a mechanical build perspective, but you trade that for design and testing/tuning complexity on the electric side. BMS, brake plausibility, motor/inverter tuning, accumulator design and manufacture, etc...

This was posted in the for sale section recently. Pretty good deal if you guys decided to go that direction.

http://www.diyelectriccar.com/forums/showthread.php/sale-pm100dx-remy-hvh250-motors-3500-192345.html
 

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What's your guys opinion on Hub motors, and controlling them. We might have the ability to get two hub motors for extremely cheap. The spec's of these motors I don't know off the top of my head, but someone has figured they are suitable.
I don't know of any hub motors off the top of my head that will run at 300V. They generally have poor specific power, as well.
 

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Hub motors also add a bunch of mass to the hubs, which means increased unsprung weight... which is bad. I don't know why hub motors would be considered, but if you go that way I suggest being prepared to explain (in the design documentation and any presentation) the reasoning behind this choice.
 

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Discussion Starter #20
You may also try contacting the manufacturer of the ME1616, Motenergy, and seeing if they could get you a custom wound version for either a higher voltage or dual 3phase system. More complex, but still a cheap option give you more power. Or just run two of them with two size6 sevcons.

Look up and PM Frodus on these forums. He can get you a good deal on controllers/motors

Sent from my iPhone using Tapatalk
My recent reply didn't include your comment, thank you for the heads up really appreciate it!

I'll definitely contact them, have you heard of other companies doing custom windings for a one off?
 
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