Search found 421 matches

by toolman2
Jun 26 2019 8:30am
Forum: Motor Technology
Topic: Revolt RV-series motor review and comparisons
Replies: 209
Views: 14802

Re: Revolt RV-120-regular

Too many pots in the fire! I unwound the stator again and that let me weigh it without bearings...4 pounds. I rounded some sharp edges where I made the wire transfer slots larger. And finally I coated the entire bare stator in electrical paint and then baked it at 300F in the oven. I should have do...
by toolman2
May 29 2019 9:35am
Forum: Motor Technology
Topic: Sanity check: outrunner with large no-load current, low inductance
Replies: 13
Views: 653

Re: Sanity check: outrunner with large no-load current, low inductance

[quote=kiwifiat post_id=1470008 time=1559089906 user_id=31725 What controller are you using or recommending that can supply the 611Amps DC required to generate 22kw at 90% eff driven at 40v? That is 2.4kw of heat, how long is a 4kg motor going to take before it turns into a demagnetized paper weight...
by toolman2
May 28 2019 10:14am
Forum: Motor Technology
Topic: Sanity check: outrunner with large no-load current, low inductance
Replies: 13
Views: 653

Re: Sanity check: outrunner with large no-load current, low inductance

Does your 120/90 motor have sufficient torque to maybe gear it down and run it slower? Eddy current losses are proportional to the square of the frequency. +1 yes, running this motor to 6500rpm unloaded would use 1kw as would producing about 40Nm (that it can do), so loaded to that level is fully m...
by toolman2
May 15 2019 10:29am
Forum: General Discussion
Topic: Tesla switches to permanent magnet reluctance motors and sees range gains
Replies: 19
Views: 1518

Re: Tesla switches to permanent magnet reluctance motors and sees range gains

PM motors at full load can achieve ~97% when everything is done perfectly. When cruising at a light load, they might be <~90% SRPM motors can achieve ~97% when everything is done right at full load, but then also cruise at light loads with minimal efficiency hit. Why you don't want one for an ebike...
by toolman2
Feb 22 2019 7:16pm
Forum: E-Vehicles General Discussion
Topic: ICE vs Electric Motor Transmissions
Replies: 81
Views: 4826

Re: ICE vs Electric Motor Transmissions

So wouldn't you rather just stick with a 1st gear as a fixed ratio transmission and have a motor with lower core losses at high speed? I generally assume a 90% efficiency per stage for a real-world gear reduction. Yes, definitely. If the selected motor did not come with comparably larger losses els...
by toolman2
Feb 22 2019 6:17am
Forum: E-Vehicles General Discussion
Topic: ICE vs Electric Motor Transmissions
Replies: 81
Views: 4826

Re: ICE vs Electric Motor Transmissions

Would the benefits of a super low speed torque gear on your race dirt bike be something you'd find useful on a road going commuter bike? In Hilly areas yes, and at least the momentary pause in torque production wouldn't matter so much. TBH i don't really use second on that bike in battle, its mainl...
by toolman2
Feb 21 2019 11:38am
Forum: E-Vehicles General Discussion
Topic: ICE vs Electric Motor Transmissions
Replies: 81
Views: 4826

Re: ICE vs Electric Motor Transmissions

Awesome to have this debate continue after a few years off. :) Its probably the most interesting one ever for me here, that i have also learnt the most from, and over time and with certain advances in EV motor and controller design i would now generally agree with Luke on this stuff, but not 100%. S...
by toolman2
Jan 03 2019 9:56am
Forum: Motor Technology
Topic: SPM VS IPM Motor - And Field weaken, is it worth it
Replies: 85
Views: 5981

Re: SPM VS IPM Motor - And Field weaken, is it worth it

One bit here i meant to get back to you about madin is the 'unwanted regen/blowing fets' thing. -If the controller is half smart about it then it continues to supply field weakening current even when you are off the throttle to keep the motors generated voltage below battery level so no regen needs ...
by toolman2
Dec 31 2018 11:23am
Forum: E-Bike Non-hub Motor Drives
Topic: Joby jm1s help needed
Replies: 5
Views: 494

Re: Need help with JOBY motor jm1s

Avi wrote:
Dec 26 2018 7:03pm
I know there are many types of encoder
 What Type would fit my motor ??
The motor have 22 poles.
 Can this idea really work ?
Thank's...
:D
Yes, this idea can really work.
by toolman2
Dec 31 2018 10:55am
Forum: Motor Technology
Topic: SPM VS IPM Motor - And Field weaken, is it worth it
Replies: 85
Views: 5981

Re: SPM VS IPM Motor - And Field weaken, is it worth it

That link to the phasor stuff is an awesome explanation Lebowski, as is your thread on the topic. Interesting that (for me at least) its 3 years later that i take the time to learn from this stuff. In my particular controller algo it will always try to make the torque producing current (Id ?) equal ...
by toolman2
Dec 30 2018 10:25am
Forum: Motor Technology
Topic: SPM VS IPM Motor - And Field weaken, is it worth it
Replies: 85
Views: 5981

Re: SPM VS IPM Motor - And Field weaken, is it worth it

maddin88 wrote "First you need to find a controller which can apply field weaken current already at 0 RPM, and second thing is you should have enough room left for BEMF to climb. Because if BEMF ((V/RPM) x RPM) starts to get higher during field weakening as battery votlage, it could blow the control...
by toolman2
Dec 27 2018 8:45am
Forum: Motor Technology
Topic: SPM VS IPM Motor - And Field weaken, is it worth it
Replies: 85
Views: 5981

Re: SPM VS IPM Motor - And Field weaken, is it worth it

Why do you think it's a bad geometry for the reluctance torque? image.jpeg Nice reference, there u have it the magnetic path through the q axis is designed to be explicitly bad to create a reluctance difference between d and q axis. Providing Reluctance torque aditional to the magnetic torque. Maby...
by toolman2
Dec 20 2018 9:17am
Forum: Items for Sale - New
Topic: Nucular electronics - complete kit for ev! [beta]
Replies: 796
Views: 67250

Re: Nucular electronics - complete kit for ev! [beta]

It's not so good for this, it uses a lot of amps to get any effect. Ive been seeing this sort of result also, using some of the most impressive (well, power density wise at 20+kw output for 2.7kg) motors on the planet like Joby's etc that are SPM -there seems to only be around 30% maximum extra rpm...
by toolman2
Nov 23 2018 7:24am
Forum: Motor Technology
Topic: Brushless motor efficiency
Replies: 25
Views: 1968

Re: Brushless motor efficiency

Hey trialspower, ive had a reasonable dabble with that motor in its many forms. They do have a fair bit of loss in the rpm department but are possibly one of the most torquey 120mm motors you are going to find, its possible to get them to 5000rpm at around 900w of rpm related losses with 30khz pwm a...
by toolman2
May 24 2018 10:16am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4130
Views: 332751

Re: Sur-Ron - New Mid drive Bike

I don't consider anything to be "beyond useful range" if it works. Its a hotrod not a commuter. This setup has a ton of pulls on it, still working perfect. Well now i don't feel so bad about blowing a few hundred watts here and there on some of my wrong choices of motors or drivetrains for race bik...
by toolman2
May 22 2018 9:40am
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4130
Views: 332751

Re: Sur-Ron - New Mid drive Bike

Jackson is going to share some controller logs. We are sagging to our 45vdc LVC cut on a fully charged 21s pack. With so much sag you loose a lot of power. 45V would be 2,15V per cell :shock: I wonder why they went with 25R and not LiPos? Indeed, so something like 22kw dissipated as heat in the bat...
by toolman2
May 21 2018 8:16pm
Forum: E-Bike Non-hub Motor Drives
Topic: Sur-Ron - New Mid drive Bike
Replies: 4130
Views: 332751

Re: Sur-Ron - New Mid drive Bike

I was shocked to see the gps logs to see 70mph, as i mentioned earlier, it was on a slightly downhill straight. Field weakening is an incredible advantage in motors that play well with tons of "weakening", which seems like an absurd misnomer for something that costs no low speed performance and jus...
by toolman2
Feb 05 2018 7:42am
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

The 154mm outrunner as it came ordered as 35kv before rewind. (40 magnets, 36 teeth) and 4.9kg 0.0263 ohms. 33.6kv A picture is worth a thousand words :D Apologies for the delay larsb. There's a pic that i posted up with this stator a page or so back, and more of the whole motor on alibaba if that ...
by toolman2
Jan 31 2018 8:34am
Forum: E-Bike Non-hub Motor Drives
Topic: higher or lower kv
Replies: 90
Views: 7171

Re: higher or lower kv

Here is an example from real life circumstances. The same everything except kv (rpm/v). 1. QS 205 V3 kv11.89 battery 72v (200A consntant capable) Sabvoton 72150 (settings: 150A battery, 300A phase) rim 17'' 2. QS 205 V3 kv9.03 battery 72v (200A constant capable) Sabvoton 72150 (settings: 150A batte...
by toolman2
Jan 26 2018 9:37am
Forum: E-Scooter and Motorcycle Photos & Videos
Topic: Suzuki GSX-R e899 K2
Replies: 376
Views: 46000

Re: Andre´s GSXR 1000 K2 with QS Motor 273 80H, 34kW

It seems you have enough room on top of the swing arm just in front of the rear tire to add a "mid"drive motor with a chain to the hub motor. That motor would also put some extra weight on the rear tire. A used motor and controller from a Zero motorcycle would be perfect. But even a 110V brushed mo...
by toolman2
Dec 03 2017 8:36am
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

About 98kv
by toolman2
Dec 03 2017 8:23am
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

Just to fill in the gaps: Joby JM1 0.01 ohms phase to phase. inductance 21.7uH. uses around 590w to do 8500rpm. JM1s 0.015 ohms inductance about 28uH used about 580w to do 8000rpm -it was an early one before they went to thinner 0.12mm lams. and the rest of the specs in the spreadsheet are correct. ...
by toolman2
Nov 30 2017 9:36am
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

The 120-100 or CA series motor (also with a bit more quality and watercooling as the colossus) is a pretty good motor, the Chinese style specs mean nothing im afraid -and this motor would be about 2 or 3% less efficient than the 154 motor but i don't think can be beaten for torque in the 120mm diame...
by toolman2
Nov 24 2017 7:02pm
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

Yep that's the same kind of motor speedmd, the one ive been working on is a 50mm stator version and has the skirt bearing -the one you have pictured is the 35mm i think. and you can get any of them on alibaba also. Yes, thats well put madin. and out of all of these types of motors, its the high pole...
by toolman2
Nov 16 2017 9:33am
Forum: Motor Technology
Topic: Motor comparison spreadsheet
Replies: 552
Views: 56170

Re: Motor comparison spreadsheet

Thanks speedmd, the d7500 is the same sort of design as those gng or bht type motors but its a fair bit bigger. The airgap is 90mm and a 60mm long stator and those outer bolt holes you can see in the case are 160mm apart, also the case is pretty long because there is a separate and adjustable hall a...