Inside my full scale AC brushless motor

Hey Etischer!! I've been following your build on another forum. How funny to run into you here. BTW, we need an update over there, I know some people are very interested in your project. See you! :)

[zeropointbug]

Originally Posted by greenlurker

Hey Etischer!! I've been following your build on another forum. How funny to run into you here. BTW, we need an update over there, I know some people are very interested in your project. See you! :)

haha, nope, not Tischer here, I just used his one pic of the rotor itself, i thought i made a note on it but i guess i neglected. my bad.

But, I am in the talks with him about getting a HOMEMADE inverter for the project, yes homemade! The guy is good with IGBT's and elbow grease!

[zeropointbug]

Wow, I didn't expect so many admiring the motor, beauty for sure!

Yes, like Brian said it's an AC Induction motor, and like Lutach posted the specs of a very similar motor, mine is only slightly more powerful (110hp @ 360volt), and lighter (175lb). It's the S20 version, new version maybe? All the Siemens number naming makes no sense. Crazy Germans.

Originally Posted by sikeston34m

No, it's not magnetized at all really.

I've seen this in the forklift AC motors at work. This is also something that throws a monkey wrench into the gears of my understanding.

I realize these are sensor based motors, but I've always wondered a few things:

#1. How does the stator conduct magnetism in such a way to get rotation? I'm sure it's in the winding. Please point me toward more information on this.

This is the beauty of an Induction motor, unlike permanent magnet type, series wound type, or other synchronous type motors, the AC inductions stator coils (stationary) have a 3 phase AC power going through them. Now there are three seperate phases in the motor which are each connected to the ends of the next one (just imagine three people holding hands in a circle), and there are also 6 poles, which if you know anything about Brushless DC motors, you times the poles by the phases... 3 phase x 6 poles = 18 coils, each phase consisting of 6 coils in series, get it? Now, imagine each AC power wave being 60 degrees out of phase to the next one, and then imagine that each coils magnetic field expanding with the AC signal, then from the starting point of the first 'sine' wave (let's call it Phase 1), 60 degrees later the phase 2 starts, then some 60 degrees later the phase 3 coil is starting it's way up. At the time the Phase 1 coil has hit zero again 60 degrees later, it goes into 60 degrees negative wave, and so on, and so on. Now try to imagine all this going on in a circular plane, there being somewhat smooth transitions between each Phase coil to the next... what do you have? A seemingly full rotating magnetic field; imagine having magnets around the perimeter of a motor case and making them spin, spinning field right, well here you are doing it with AC magnetic fields. Invented by the magnificent Nikola Tesla over 100 years ago, some think he was an alien brought here because he invented the 20th century, way ahead of his time.

Anyways part two, the rotor...

Okay, this is super simple really, have you ever had a Neodymium magnet and held it close to alum. or copper plate? Well, nothing happens right? Well as soon as you start to move it, there is resistance, the faster you move it, the more resistance that is apparent. That's because for every action there is an opposite, but equal REACTION (well with magnets it's not quite equal), the MOVING magnetic field in the magnet is INDUCING a magnetic field INTO the very material you are moving it along, the magnetic field induced will naturally be OPPOSITE that of the magnet pole facing it. When you stop moving it, it disappears, when you go, it repels, get it? It's an active dynamic relationship.

NOW, imagine that rotating magnetic field I explained, the rotor is not more than a hunk of aluminum, well aluminum bars actually under that sheathing... anyways, the rotating magnetic field going on around it is INDUCING (hence Induction motor) a magnetic field into the rotor which will be opposite the fields and repel, yada, yada... now to control the speed of the motor, you have a variable frequency controller (inverter), electric car inverters can do 0 - 400 Hz operation, the higher the frequency, the faster the rotating magnetic field is spinning, and the faster the field is spinning, the motor magnetic 'slip' it's called is placed on the rotor, which creates more repulsion, and thus more torque, and power.

My fingers hurt, I think I touched on the basics, err, fundamentals of how it works.

BTW, the rotor weights 34lbs, pretty light really considering how much weight it will be moving!


#2. Can these be used in a sensorless setup? Do they Generate enough EMF to go sensorless?

By now you probably know this answer?

[MTBikerTim]

Hey ZPB, Glad to see some progress on the full scale conversion. Have you had any more luck sourcing the controller? I remember that's where you were stuck when I last talked to you.

[zeropointbug]

Originally Posted by MTBikerTim

Hey ZPB, Glad to see some progress on the full scale conversion. Have you had any more luck sourcing the controller? I remember that's where you were stuck when I last talked to you.

Hey man, yah, progress, if you want to call it that!

ETischer is the guy (Eric Tischer), if you missed it in my last post, I might get an inverter from him, homemade from industrial inverter and some great big IGBT's.

[zeropointbug]

Hey Lutach, you wouldn't know where I could get a hold of a Simovert Inverter would you? My plan when I bought these motors was to use the Simovert, but Metricmind (North Am. distributor) can't sell the inverter WITHOUT a package motor... nonsense if you ask me. Just puts a hamper on electric car development, you know?!

It's either we buy a MES-DEA inverter (Swiss made), $5500, and he doesn't gaurantee it to operate properly, and we can't change the software parameters either to make it work. Sad situation really, so we are trying to get rid of the motors somehow.

[lutach]

Originally Posted by zeropointbug

Hey Lutach, you wouldn't know where I could get a hold of a Simovert Inverter would you? My plan when I bought these motors was to use the Simovert, but Metricmind (North Am. distributor) can't sell the inverter WITHOUT a package motor... nonsense if you ask me. Just puts a hamper on electric car development, you know?!

It's either we buy a MES-DEA inverter (Swiss made), $5500, and he doesn't gaurantee it to operate properly, and we can't change the software parameters either to make it work. Sad situation really, so we are trying to get rid of the motors somehow.

I'll send Siemens and e-mail, not sure if the electronic components I sell to them goes to the automation devision that makes the Simovert Inverters. You can also look into an AC Propulsion, Saminco, Aveox, Semikron, Sevcon (Depending on voltage you plan on using) or Curtis (Depending on voltage you plan on using). I contacted Brusa to see if they were able to make a 500KW inverter, but all they said they could do was 200KW+.

Edit: Forgot to mention M.S. Kennedy, they have 3 models under motor controls page 2. Not sure if they are a complete system, but it's worth a try.

Haha... that is funny. Well, quite an interesting project nonetheless. You guys are insane... homemade gear of that magnitude?! Best of luck :D

[doo540]

Can some one please post some links to some good forums on full size vechile conversions?

[lutach]

Originally Posted by doo540

Can some one please post some links to some good forums on full size vechile conversions?

http://www.evforum.net/forums/
http://endless-sphere.com/forums/index.php (I've seen RC-Monster's member(s) there)

[zeropointbug]

Thanks Lutach, I didn't know you were so connected. BTW, it's Automotive division... ;)

BRUSA is a joke if you ask me, for SURE they have the best components out there as far as quality and compactness (inverters are small), but the price.... $22,000 for a 100hp motor?! Come on, and $9000 for there 50kW inverter! How do they expect that to be feasible? If they are going to charge that much, then at least make some high powered units, something around 250Kw+.

Saminco, there inverter is not powerful enough. Aveox doesn't have anything. Semikron, nor Sevcon, I couldn't find any inverter at MS Kennedy, it think you were looking at an IGBT pack, the powre stage of an inverter.

AC Propulsion, I would love to use there system, $22,000 for motor/controller package, with built in 20kw battery charger, 220hp. They designed the power propulsion for the Tesla Roadster.

The best motors though, are made by UQM, they have a 125kw (167hp) motor system which weights 90lbs! $22,000 for motor/controller package. If i had the money, I would use it in my other EV project (light weight, high performance car) targeting 1000lbs curb weight, with at least 120hp, should get you from 0-60mph in < 4 secs, I'm aiming for 3 seconds. Won't be too hard with such a light weight. I'm also thinking of implementing a 10kw generator for long trips, with 200+mpg.

[lutach]

Originally Posted by zeropointbug

Thanks Lutach, I didn't know you were so connected. BTW, it's Automotive division... ;)

BRUSA is a joke if you ask me, for SURE they have the best components out there as far as quality and compactness (inverters are small), but the price.... $22,000 for a 100hp motor?! Come on, and $9000 for there 50kW inverter! How do they expect that to be feasible? If they are going to charge that much, then at least make some high powered units, something around 250Kw+.

Saminco, there inverter is not powerful enough. Aveox doesn't have anything. Semikron, nor Sevcon, I couldn't find any inverter at MS Kennedy, it think you were looking at an IGBT pack, the powre stage of an inverter.

AC Propulsion, I would love to use there system, $22,000 for motor/controller package, with built in 20kw battery charger, 220hp. They designed the power propulsion for the Tesla Roadster.

The best motors though, are made by UQM, they have a 125kw (167hp) motor system which weights 90lbs! $22,000 for motor/controller package. If i had the money, I would use it in my other EV project (light weight, high performance car) targeting 1000lbs curb weight, with at least 120hp, should get you from 0-60mph in < 4 secs, I'm aiming for 3 seconds. Won't be too hard with such a light weight. I'm also thinking of implementing a 10kw generator for long trips, with 200+mpg.

I've been trying to make my own electric vehicle since 1994 when I started messing with brushless in R/C. I was too young back then and now people are too greedy and prices have gone through the roof. They don't have the automotive devision anymore. The Simovert is made in the Automation Devision, I might be wrong as they have a lot of devision and plants spread around the globe.

Brusa is a joke, but they have the product.
Try this: http://www.isecorp.com/ise_products_.../inverters.php.

Saminco has made inverters for record speed runs. Aveox can make motors for good for 150Kw and controllers good for 800V and 200A http://www.aveox.com/Products-Controllers.aspx. Semikron has the Semistack for Automotive use http://www.semikron.com/internet/index.jsp?sekId=356. Sevcon has the espAC http://www.sevcon.com/pages/espac.html, but it's only good for 80V, but you can contact them to see if they can make one for higher voltage. Curtis Model 1238, but same situation as Sevcon. Here is the info on M.S. Kennedy motor controller: http://www.mskennedy.com/client_imag...les/4850re.pdf, http://www.mskennedy.com/client_imag...les/4851re.pdf and http://www.mskennedy.com/client_imag...les/4852rd.pdf. Kelly has brushless controllers too 120V 200A cont. http://www.kellycontroller.com/. UQM was also an option, but their price is up there. Raser Technologies makes some good stuff too http://www.rasertech.com/. There are many others in other countires and there's the system I'll be using for my super car which I can't give that info out .

[lutach]

I just have tons of info on this subject and I can go on forever . Here is a very nice conversion: http://www.electric7.com/.

As for my electric car, I shared some of the basic info with a top engineer at Flextronics Brasil and he was impressed. With one of the ideas I have he calculated a range of close to 500 miles at a speed of 65-80MPH. This was calculated with the weight of a Corvette. The drive system has enough power to push the Corvette to over 200MPH incase any one tries to bring out the "Electric are too slow" crap.

[BrianG]

Unless battery technology changes dramatically, or solar power becomes much more efficient, I don't think we will see high power and long range in the same vehicle very soon. Power is V X A, and even a HV setup will pull some serious current to get high HP figures.

So, what about the use of turbine engines as a generator? I would imagine an engine could be tuned for maximum efficiency for a certain rpm and could run that all the time. And a turbine has less losses IIRC (higher efficiency). So, hook up a small ~50HP one to charge the batteries. For most people, a measely 200HP is all that's needed for decent launches (barring racing), and it only takes a small fraction of that power to keep a car moving at highway speeds. So, the batteries would provide the current peaks for starts, and they would be continually charged by the generator. You'd still have a range limit when you run out of fuel or your discharge is greater than the battery mAh combined with the charge rate of the engine/generator.

Twin 500HP motors with a 200m range? Hmm, let's see; 1000HP is 746,000w. If "only" 5% of that is needed to maintain normal speeds on the highway, that's still 37,300w (50HP). At say 400v, that's over 93A. To get 200m range at 70mph, you'd need 2.85 hours of runtime. That equates to 265Ah. Even doubling that voltage would still need ~132Ah. Still a lot of cells no matter how you set up the voltage. So, there's gotta be something to charge the system to get that kind of runtime. Or am I way off base here?

[lutach]

Originally Posted by BrianG

Unless battery technology changes dramatically, or solar power becomes much more efficient, I don't think we will see high power and long range in the same vehicle very soon. Power is V X A, and even a HV setup will pull some serious current to get high HP figures.

So, what about the use of turbine engines as a generator? I would imagine an engine could be tuned for maximum efficiency for a certain rpm and could run that all the time. And a turbine has less losses IIRC (higher efficiency). So, hook up a small ~50HP one to charge the batteries. For most people, a measely 200HP is all that's needed for decent launches (barring racing), and it only takes a small fraction of that power to keep a car moving at highway speeds. So, the batteries would provide the current peaks for starts, and they would be continually charged by the generator. You'd still have a range limit when you run out of fuel or your discharge is greater than the battery mAh combined with the charge rate of the engine/generator.

Twin 500HP motors with a 200m range? Hmm, let's see; 1000HP is 746,000w. If "only" 5% of that is needed to maintain normal speeds on the highway, that's still 37,300w (50HP). At say 400v, that's over 93A. To get 200m range at 70mph, you'd need 2.85 hours of runtime. That equates to 265Ah. Even doubling that voltage would still need ~132Ah. Still a lot of cells no matter how you set up the voltage. So, there's gotta be something to charge the system to get that kind of runtime. Or am I way off base here?

When I saw what SSC posted, I thought he found some alien technology and I know most of it is like any hyper marketed product. They must say good things to get big money fools to back them up. I hope he can back it up which will be great for the auto industry, but as of now all of it is BS.

I would love to post some of my ideas here, but would hate to see it being used by someone else. With all the components for my car working properly, I can get probably over 1000 miles. The figures have been confirmed by a great team of engineers working for one of the biggest EMS companies and by a great friend of mine who used to prepare my go kart for racing. He btw is a aerodynamic expert who helped me figure out the best possible drag co efficiency to get the numbers I was looking for. It only takes about 20Kw or less (Weight of vehicle and drag co efficiency plays a major part on this) to get a car to maintain 65-80MPH and it only takes that because of the size of these motors being used which makes tons of torque. Electric motors makes power from torque and beyond a certain RPM range that torque goes down and Kw goes up.