DIY Electric Car Forums banner
1 - 20 of 22 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
Hi,

Fortunately, more and more Tesla Model 3 cars meet an early demise and end up being torn apart for parts. So, prices of the motor/dif unit of these cars are comming down. Now of course many people earning their cash with those parts will tell you you need the matching Tesla controller / electronics. But why? To me it seems any controller for brushless 3-phase motors should be able to make it spin. Maybe some electronics inside the unit (don't think there are any) need to be taken out of the equasion, but I think it has 3 big wires wanting a voltage difference to make current, magnetic flux, and make the lot spin. Am I correct in this assumption?

(BTW, reason for asking is I would like to fit such a unit to the rear subframe of my Miata NB, and make a homebrew controller. Later, much later...)

Cheers,

Hugo
 

·
Registered
Joined
·
3,036 Posts
As long as you can make it happy with creepage distances, water and dust ingress, and cooling attachments, of course you can.

Your time needs to be totally worthless to go to that much trouble and risk, though.
 

·
Registered
Joined
·
124 Posts
Yes, It can in theory. If i were to do it, i'd remove the inbuilt inverter from the side of the motor, then interface directly to the 3 phase wires of the motor and the hall encoder.
In its most basic form, that is the main wiring connection to the motor to make it spin. Beyond that, how good is your inverter?
 

·
Registered
Joined
·
3,036 Posts
Yes, It can in theory. If i were to do it, i'd remove the inbuilt inverter from the side of the motor, then interface directly to the 3 phase wires of the motor and the hall encoder.
In its most basic form, that is the main wiring connection to the motor to make it spin. Beyond that, how good is your inverter?
It's not a hall encoder, lol.

It's also not "all ya gotta do, is..."

Need to excite the resolver, decode it, sense current in the three windings, interface to temperature sensors, among all the PiTA mechanical/thermal stuff.

Yes, it can be done. The inverter only needs to put out 40V to spin it, so, how much power do you need, not how good is your inverter.
 

·
Registered
Joined
·
124 Posts
yes, its very complicated. Im not here to hold his hand and tell him, are you? If he really wants to do it, He will figure it out, or he wont.
His question was asking if the basic connections to the physical motor were the same as any other motor. Yes, they are.

Pull one apart and figure it out. take pics. Show everyone as you go so the info is there for the next person who comes along to try it.
 

·
Registered
Joined
·
3,036 Posts
No they are not the same. You said hall sensors. Some motors use them. A Tesla motor doesn't.

If you don't know anything about electronics or motors, working a Tesla motor is jumping headfirst into the deep end...with no water in the pool.

The motor and inverter are electrocution hazards if you run them open like this. Safer to stick a fork in a toaster.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #9 ·
Thanks for all the input. Should I take the plunge (I'm also considering Axial flux motor, but then I need to to the mechanical drive myself), the plan is to bypass anything Tesla specific. Maybe even fit Hall sensors myself. So I have a 3-phase motor with Hall sensors. I've made controllers for those before, from RC stuff to 10kW bikes. Yes, this will be bigger and more dangerous, but who knows. I tried a lot of weird things and non killed me so far. Didn't stick a fork in the toaster, yet, will try at the weekend brunch ;)

Cheers,

Hugo
 

·
Registered
Joined
·
124 Posts
No they are not the same. You said hall sensors. Some motors use them. A Tesla motor doesn't.

If you don't know anything about electronics or motors, working a Tesla motor is jumping headfirst into the deep end...with no water in the pool.

The motor and inverter are electrocution hazards if you run them open like this. Safer to stick a fork in a toaster.
Oh noes, I said hall sensor, What an egregious mistake....
You really going to be pedantic about stupid bullshit in an irrelevant thread?

Have you even built anything yet? or are you just all talk and bullshit? Just another keyboard mechanic?
 

·
Registered
Joined
·
3,036 Posts
Oh noes, I said hall sensor, What an egregious mistake....
You really going to be pedantic about stupid bullshit in an irrelevant thread?

Have you even built anything yet? or are you just all talk and bullshit? Just another keyboard mechanic?
Son, you were still shitting in your pants when I was practicing engineering.

It's not pedantic. You were being an idiot. This is not Ann Landers or Ask Heloise. People reading this thread will think, "hmm, hall effect, I did that with my RC cars, so I'll buy an LDU". You now have OP talking about using hall effect, idiot.

No, dear child, it's not pedantic. At these power levels, you have to accurately determine the position of the rotor. If you don't, break out the kleenex tissues, because you'll have built yourself a 300lb vibrator.

I'll be nice and not tell you where to shove your homebrew vibrator because you were not grown up enough to learn vs being offended and defensive when you were WRONG. F*cking snowflakes.
 

·
Registered
Joined
·
124 Posts
hahaha, go fuck yourself old man, Time to retire and move on you senile old fuck.
Son, you were still shitting in your pants when I was practicing engineering.
So no? you haven't/aren't building anything? You'll just claim to know everything current because you used to have a job doing it, what 40? years ago? Wow, you are a special one aren't you.

Go do something with your life instead of being a loser hanging around online all day. Do you not have real friends? a real life? Its a shame Im not a mod, because id abuse my powers and delete everything you post, any time you post anything.
 

·
Registered
Joined
·
124 Posts
No, I just don't like Remy, because hes a rude fuck to pretty much anyone who comes along. great way to motivate people to not join in your forum is to have an idiot at the door driving people away.
This used to be how the internet was a few decades ago, the gatekeeping and assholery. The world has moved on.
 

·
Registered
Joined
·
306 Posts
Hi,

Fortunately, more and more Tesla Model 3 cars meet an early demise and end up being torn apart for parts. So, prices of the motor/dif unit of these cars are comming down. Now of course many people earning their cash with those parts will tell you you need the matching Tesla controller / electronics. But why? To me it seems any controller for brushless 3-phase motors should be able to make it spin. Maybe some electronics inside the unit (don't think there are any) need to be taken out of the equasion, but I think it has 3 big wires wanting a voltage difference to make current, magnetic flux, and make the lot spin. Am I correct in this assumption?

(BTW, reason for asking is I would like to fit such a unit to the rear subframe of my Miata NB, and make a homebrew controller. Later, much later...)

Cheers,

Hugo
Hi you could take a look at Home - openinverter.org - Open Source AC motor inverter for some ideas and also Damien Maguire's You Tube channel. https://www.youtube.com/c/Evbmw/videos
Most of it is regarding the elder Tesla S Model using the induction motor which is easier to control than the newer Model 3.
Also in some cases they use the original Tesla Power Drive Unit by just "hacking" the logic part with a custom logic card.
 

·
Registered
Joined
·
19 Posts
Discussion Starter · #18 ·
Thanks for the on-topic and non-verbally-abusive reply, it is appreciated. I don't have the English vocabulary to search, sites like the ones you link are a great help not only on the topic but also on expanding my vocabulary and therefore googling-abilities. I know the Model 3 motor is different, is basically boils down to field orientated controls as they changed the magnet positions. I built controllers with that before, for home-made brushless motors. Downside would be having to figure out the correct settings, as they are seemingly endless, without detailed knowlegde of what is inside the motor.

Again thanks for the input, my investigation and learning exersize continues.

Hugo
 

·
Registered
Joined
·
36 Posts
Hi,

Fortunately, more and more Tesla Model 3 cars meet an early demise and end up being torn apart for parts. So, prices of the motor/dif unit of these cars are comming down. Now of course many people earning their cash with those parts will tell you you need the matching Tesla controller / electronics. But why? To me it seems any controller for brushless 3-phase motors should be able to make it spin. Maybe some electronics inside the unit (don't think there are any) need to be taken out of the equasion, but I think it has 3 big wires wanting a voltage difference to make current, magnetic flux, and make the lot spin. Am I correct in this assumption?

(BTW, reason for asking is I would like to fit such a unit to the rear subframe of my Miata NB, and make a homebrew controller. Later, much later...)

Cheers,

Hugo
Have you tried EVControls.com and I understand ZeroEV.co.uk also have a controller that interfaces with the Tesla inverter.

I have just received the EVControls Model 3 controller interface as they seem the best price by far. Beware as only the rear motors have the capacity to be controlled. The front motors are slaves.
 
1 - 20 of 22 Posts
Top