Search found 192 matches

by Biff
Aug 15 2018 9:25am
Forum: E-Scooter and Motorcycle General Discussion
Topic: List of racing E-motos
Replies: 14
Views: 1046

Re: List of racing E-motos

Don't forget about the Australians too. Ripperton, Voltron and CataVolt, all 3 are dedicated pioneers and worthy of an entry in your list of historic electric race motorcycles. http://elmoto.net/showthread.php?t=2136 https://insideevs.com/voltron-evo-much-never-enough-wvideo/ http://members.dodo.com...
by Biff
May 14 2018 5:08pm
Forum: E-Vehicles General Discussion
Topic: Sevcon Self Characterisation Wizard
Replies: 6
Views: 919

Re: Sevcon Self Characterisation Wizard

I have been working with Sevcons for about 7 years now and have not ever come across that software. I saw in your screen-shot that the copyright notice in there is 2007 - 2010. I bet that the software has not been used or updated by Sevcon for a very long time and is simply not compatible with the I...
by Biff
Mar 16 2017 6:52pm
Forum: Motor Technology
Topic: QS motor magnet max temp before demag ?
Replies: 27
Views: 2081

Re: QS motor magnet max temp before demag ?

I have found that magnets demag at much lower temperatures when they are not in motors.
by Biff
May 25 2016 8:04pm
Forum: Motor Technology
Topic: Sevcon Gen 4 Fault Question: Changing CAN Node
Replies: 10
Views: 623

Re: Sevcon Gen 4 Fault Question: Changing CAN Node

use dvt helper menu item to "find range errror" I suspect it is the "Emergency (EMCY) telegram COB-ID" object 0x1014 Node 1 value is 0x00000081 I think it is supposed to be 0x00000082 for node 2 etc., but not sure. put the controller in pre-op, change the param, then put it back in operational, powe...
by Biff
Apr 08 2015 3:04pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: About Sevcon Gen4 Motor Controller
Replies: 1
Views: 492

Re: About Sevcon Gen4 Motor Controller

in DVT helper look at the TPDO/RPDO tab, that will tell you what the data is in those TPDO's if you want to decode it in your own program. you can launch the DVT Vehicle interface (click on the wheel icon in the Main DVT program) that will connect to the controller, read the TPDO configuraiton and t...
by Biff
Dec 16 2014 7:35pm
Forum: E-Scooter and Motorcycle General Discussion
Topic: how to program a sevcon gen4
Replies: 179
Views: 53575

Re: how to program a sevcon gen4

Oh oh, running a gen4 size 4 with a ME0913 it looks fine until I throttle up above 2000 rpm the motor spins out of control stops brutally and gives these two messages on the DVT: 0 : 0x52c3 Current Control Fault 1 : 0x51319 Mtr Slv in Wrong State I did not setup any master slave as it's a single mo...
by Biff
Nov 13 2014 1:38am
Forum: Motor Technology
Topic: Farfle's Mk 4.5 outrunner
Replies: 33
Views: 2744

Re: Farfle's Mk 4.5 outrunner

The model I used was just like the one that Farfle posted, I just extended the depth. it is a planer model. I posted my script and parsing spread sheet to this forum in 2011, I think it should still be around if you search. I can post agiain, but will have to update it abit because there is alot of ...
by Biff
Nov 12 2014 1:19am
Forum: Motor Technology
Topic: Farfle's Mk 4.5 outrunner
Replies: 33
Views: 2744

Re: Farfle's Mk 4.5 outrunner

I got a chance to update your .fem to work with my scripts, here are the preliminary results I think the high frequency might be due to the loose meshing. The simulation had around 8,000 nodes, my "fine" meshes usually have 80,000. it made this simulation run in a few minutes rather than 30-40 minut...
by Biff
Nov 05 2014 1:39pm
Forum: Motor Technology
Topic: Farfle's Mk 4.5 outrunner
Replies: 33
Views: 2744

Re: Farfle's Mk 4.5 outrunner

looking at the FEMM plot, it seems there is alot of material pushing 1.8T, that could lead to pretty high hysterisis losses at high speed, but since you probably aren't going to be high speed for long periods, (drains the batteries too quickly) you might be all right. Send me the .fem file and I'll ...
by Biff
Sep 26 2014 12:23pm
Forum: Motor Technology
Topic: Field Weakening VS Gear Box VS Higher voltage battery
Replies: 145
Views: 12418

Re: Field Weakening VS Gear Box VS Higher voltage battery

one thing that hasn't been mentioned is that when designing a system, it is important to balance acceleration and cruising speed and efficiency. Most electric vehicles are not expected to operate at their top speed, high speed usually means higher than sustainable power levels, or extremely reduced ...
by Biff
Aug 30 2013 2:18pm
Forum: Motor Technology
Topic: 12 kw rc motor
Replies: 1876
Views: 198466

Re: 12 kw rc motor

Biff, Thanks so much for sharing all that. Very interesting about the tooth geometry. Once the design is good, can you increase the stator and magnet lengths and expect the same good result but higher power, or are you back to only somewhere between revision 1 and 40? with a radial design for the m...
by Biff
Aug 30 2013 10:08am
Forum: Motor Technology
Topic: 12 kw rc motor
Replies: 1876
Views: 198466

Re: 12 kw rc motor

Miles wrote:
Biff wrote:Arlo asked why not have a 24tooth 22pole tooth design. That is a good magnetic design, I don't know why they wouldn't pick that combination.
Because there is only one winding symmetry?
possibly
by Biff
Aug 30 2013 3:08am
Forum: Motor Technology
Topic: 12 kw rc motor
Replies: 1876
Views: 198466

Re: 12 kw rc motor

it is important to note that waveform shape has alot to do with the magnet and tooth head geometry. A very subtle change in the interface can have significant impact on the BEMF waveform (but might not affect Kv that much). When I design a motor, I can spend a significant effort refining that partic...
by Biff
Aug 27 2013 9:35pm
Forum: Motor Technology
Topic: 12 kw rc motor
Replies: 1876
Views: 198466

Re: 12 kw rc motor

With 28s poles you don't need to take it to 9000 RPM, because it will make the same power at 6400 (9000/6400 = 28/20). And it will have the same losses. EDIT: and the same electrical frequency. And the same amps. And the same battery. I can not make my point any clearer. I believe you are incorrect...
by Biff
Jul 27 2013 10:09pm
Forum: Motor Technology
Topic: Using femm
Replies: 56
Views: 5500

Re: Using femm

Answer 1 and 2) You put the current you want at that instant on each phase. If you want to simulate the torque produced at one instant when 100A RMS is being delivered, you need to know what phase angle you want to simulate (call it phi), then you would set phase A as 100 * sin(phi) Phase B = 100 *...
by Biff
Jul 25 2013 11:17pm
Forum: Motor Technology
Topic: Using femm
Replies: 56
Views: 5500

Re: Using femm

Answer 4) I don't know of a way to change the number of turns at one time. Sometimes I go in a text editor and edit the nodes, its not that difficult when there aren't very many coils, and it is very easy to just calculate what effect changing the number of coils will have in your post processing sp...
by Biff
Apr 02 2013 11:24pm
Forum: Motor Technology
Topic: Estimating max torque/speed 15" dia - 3" wide ring outrunner
Replies: 16
Views: 992

Re: Estimating max torque/speed 15" dia - 3" wide ring outru

I would bet with that dimension you can get about 600Nm of torque, or 120kW at 2000 RPM for short periods.

It would have no problem driving an EV.

If you want to see what a big outrunner can do, look at protean http://www.proteanelectric.com/

-ryan
by Biff
Apr 02 2013 11:15pm
Forum: Motor Technology
Topic: Sevcon Gen4 Problem - any tips?
Replies: 24
Views: 5215

Re: Sevcon Gen4 Problem - any tips?

Hi Ryan, which window do you mean? The one in the middle? If so this is mostly empty.. I am talking about the CAN window , it is 2 spaces up and on the left half of the screen from the photo you took. Take a photo of the entire screen (or save a screen shot by pressing your Print Screen key on your...
by Biff
Mar 30 2013 11:33pm
Forum: Motor Technology
Topic: Sevcon Gen4 Problem - any tips?
Replies: 24
Views: 5215

Re: Sevcon Gen4 Problem - any tips?

When you launch the DVT program can you see messages in the CAN message window?

IF you query flts what is the response?

-ryan
by Biff
Mar 02 2013 2:26am
Forum: Motor Technology
Topic: Conclusive proof gearboxes are awesome.
Replies: 790
Views: 70879

Re: Conclusive proof gearboxes are awesome.

I can't read German, but I am willing to bet that the article discusses "adding a gearbox when using this motor adds efficiency". I don't doubt that could be ture, and that is a relatively easy question to answer. The more difficult question is: Given a production budget of $___ , a weight of ___kg,...
by Biff
Feb 23 2013 2:09am
Forum: Motor Technology
Topic: Conclusive proof gearboxes are awesome.
Replies: 790
Views: 70879

Re: Conclusive proof gearboxes are awesome.

I think a big misconception in this thread, is that you get some magic trick of using less power if the motor is spinning much faster. The reality is, the least amount of energy you're going to use to create a given torque from a motor will be the lowest RPM you can create this torque you require a...
by Biff
Jan 06 2013 2:32pm
Forum: Motor Technology
Topic: Rickys High Power Flexable motor controller
Replies: 368
Views: 44011

Re: Rickys High Power Flexable motor controller

Sevcon doesn't have a hard limit, with previous firmware current control got sketchy above 500Hz so they didn't recommend exceeding that. Sevcon is continually updating their firmware so you might be able to push things past 500Hz now, but don't expect it to go much past that, 550, maybe 600Hz if yo...
by Biff
Oct 03 2012 12:34am
Forum: Motor Technology
Topic: Using femm
Replies: 56
Views: 5500

Re: Using femm

Quite often it will hang and run out of memory if you have a very small area that is trying to be meshed, such as an area that is created between an arc and line that is tangent to that arc. It usually gives a coordinate point at which it ran out of memory, you zoom to that area and see if there is ...
by Biff
Sep 21 2012 5:18am
Forum: E-vents
Topic: bairdco racing at adams, september 15, 2012
Replies: 114
Views: 15632

Re: bairdco racing at adams, september 15, 2012

Thanks for the video Farfle, looked like a bunch of fun. Wish I could have been there.

-ryan
by Biff
Sep 12 2012 12:39am
Forum: Motor Technology
Topic: 12 kw rc motor
Replies: 1876
Views: 198466

Re: 12 kw rc motor

Buries timing boards are awesome I have 3 of them and for a motor using halls all the time yes its great. But you will find the no load advance vs the loaded advance to be quite different. Just like an ICE at idle you up the advance and it idles higher and stronger but when you put you foot down an...