[SyCo]

I'm new to the EV world. I bought a unfinished project see here http://www.diyelectriccar.com/forums...-ac-38064.html

I've got some specs about the motor but since I'm a newbie, I don't know if everything I need is there.

ASDA4004
15.5 KW
3 o
30.3 V
405 A
90 Hz
1735 rpm
cos 0 0.831
Duty S2-60 minutes

With the information above, can I know how many "poles" the motor have ?


According to that pic:


Is 1735 rpm the maximum RPM or I can go higher ?

thank you

[major]

Originally Posted by SyCo

I've got some specs about the motor but since I'm a newbie, I don't know if everything I need is there.

ASDA4004
15.5 KW
3 o
30.3 V
405 A
90 Hz
1735 rpm
cos 0 0.831
Duty S2-60 minutes

With the information above, can I know how many "poles" the motor have ?


According to that pic:


Is 1735 rpm the maximum RPM or I can go higher ?

Hi Sy,

RPM = Freq * 120 / p

Freq in Hz, p = # of poles. This gives you the synchronous speed. Induction motors will run less by a few percent (slip).

So you have 90 Hz, 1735 (use 1800 as synch RPM) which makes it a 6 pole motor.

The curve shows it up to 4500 RPM, so I guess that would be O.K.

Regards,

major

[SyCo]

Originally Posted by major

Hi Sy,

RPM = Freq * 120 / p

Freq in Hz, p = # of poles. This gives you the synchronous speed. Induction motors will run less by a few percent (slip).

So you have 90 Hz, 1735 (use 1800 as synch RPM) which makes it a 6 pole motor.

The curve shows it up to 4500 RPM, so I guess that would be O.K.

Regards,

major

Wow that's great details. So it is a 6 pole motor.

About the "slip" I have a setting in the controller menu (Curtis 1238 AC) called "SlipGain". Do you know if I should set this value ? Currently it is set at 5.01. I've messed with it because previously it was 3.xx.

For the RPM... at around 1700rpm it shows 20KW, at 4000rpm it shows 12KW and finally at 4500rpm it shows 0KW. I see the mechanical power decrease as does the torque. Does it mean it is better to work at the rated 1700rpm (what does this stand for actually ??) or it means I can use the motor up to 4000 rpm depending of my setup ?

thank you

[SyCo]

Some development... before posting this thread, the controller was set to "4 pole" and "64 steps" for the encoder (as specified on motor sheet for the encoder). With those settings I was not able to reach more than ~450rpm @ 100% throttle. I thought it was the encoder so I set it to "32" steps. Now I was able to reach ~1700rpm @ 100% throttle but it was kind of slow.

After I've read major's answer, I've set my controller to "64 steps" and "6 pole"... WOW what a difference. I'm now reaching ~1700 a LOT faster than before.

I'm also in contact with someone at Curtis Instruments and it seems that with my specific handheld programmer I can "learn" my motor charateristics... I'll let you know the results.

Now anyone knows about the max RPM I can use ?

[major]

Originally Posted by SyCo

Now anyone knows about the max RPM I can use ?

The curve shows 4500. Why not use that?

[SyCo]

Originally Posted by major

The curve shows 4500. Why not use that?

hum well don't forget I'm still new at this

I was asking because the motor sticker say "1735 rpm" (pic below). Doesn't that mean MAX rpm ?

and because the previous owner made a 1:2 multiplication gearbox (well with chain and sprockets) so if I use all 4000 rpm my flywheel will reach ~8000rpm.

and finally, I thought it was best with electric motor to use kinda low RPMs with high torque ?!

btw I really want to learn, so any help is always appreciated ... even if I seem to came from far way in term of EV knowledge usually I'm learning quite fast.

[major]

Originally Posted by SyCo

I was asking because the motor sticker say "1735 rpm" (pic below). Doesn't that mean MAX rpm ?

No, that is just the power rating figure.

And I can't believe that guy geared down the motor to the tranny, 1:2. Reverse those sprockets if you can. Better yet, go one to one. You still got 4 or 5 gear ratios in the tranny to choose from, right? Oh well, you can just keep it in first for now.

So with that in mind, set the max motor RPM to 3000, that would be 6000 on the tranny input. It doesn't mean you need to use all of that.

I'd think you'd want to be running this motor at about 3 to 4000 RPM for cruise speeds. If you can tune the controller for it and have high enough voltage, I'd run the darn motor to like 6 or 7000 RPM. Maybe higher. Get those sprockets right and try some high RPM.

major

[SyCo]

@major

Thanks a lot... for now I don't want to mess too much with the mechanical part. Winter is coming here (up north) and I'm limited in garage space and tools. During the summer I can go to my dad's garage where we have a lot more space and tools.

So I will take your recommendations and try to setup that thing to run at a higher RPM and choose the appropriate gear for now.

I'm still waiting at Curtis Instruments for the motor learning procedure so I don't want to push that RPM too high.

And I also need to evaluate and choose what batteries I'm going to purchase.