Search found 30 matches

by ElectronS
Feb 14 2019 1:29pm
Forum: Motor Technology
Topic: BESC - beefed up VESC motor controller for high power ebikes
Replies: 142
Views: 23028

Re: BESC - beefed up VESC motor controller for high power ebikes

nice work :bigthumb:

the copper busbars are soldered ??? watch out for the fact the the pcb and the copper have different thermal expansion , so this might cause problems later .
by ElectronS
Oct 07 2018 3:38pm
Forum: Motor Technology
Topic: How much Heat can To-247 handle in real world
Replies: 10
Views: 1197

Re: How much Heat can To-247 handle in real world

One thing to be aware of is much of the time TO-247 are limited by the wirebond to the source pin, it's not uncommon to see 200A+ mosfets dies in TO packages with a 100A limit on the wirebond. You have to check the data sheet for any mention of package limitations. old to-247 packages like IRFP3077...
by ElectronS
Oct 05 2018 10:22am
Forum: Motor Technology
Topic: How much Heat can To-247 handle in real world
Replies: 10
Views: 1197

Re: How much Heat can To-247 handle in real world

Electron, I'm an ol' guy now...and have forgotten the specifics of this calculation I did back in 2012. There should be a thread on here with a deeper discussion. Note the significance of switching losses versus conduction losses at high PWM frequencies. Thank u all , you have opened my eyes on the...
by ElectronS
Oct 04 2018 5:36am
Forum: Motor Technology
Topic: How much Heat can To-247 handle in real world
Replies: 10
Views: 1197

Re: How much Heat can To-247 handle in real world

Those are TO-220's not TO-247's. To figure out max temp you need two things: 1) Heat. For static loads it's easy; it is I2R where R is RdsON. For switching loads it is a lot harder, since you have dynamic losses as well, and these depend on a great many things (like Miller capacitance, which change...
by ElectronS
Oct 04 2018 5:32am
Forum: Motor Technology
Topic: How much Heat can To-247 handle in real world
Replies: 10
Views: 1197

Re: How much Heat can To-247 handle in real world

What does the RDSon go up to at those temperatures? The resistance goes up with temperature, which generates more heat, which raises the temperature....so you have to account for that, too. Also, I'd recommend assuming worst-case thermal resistances between all the parts and heatsinks/etc., just in...
by ElectronS
Oct 03 2018 7:58am
Forum: Motor Technology
Topic: How much Heat can To-247 handle in real world
Replies: 10
Views: 1197

How much Heat can To-247 handle in real world

Hi guys i am a newbie EE building a 2 parallel mosfet per side power stage , and would like to know how much current is possible to pass for 2 minutes (peak) and 60mins continous. by figuring out how much thermal power a to-247 package can handle from your experience . The power stage will be someth...
by ElectronS
Mar 29 2018 7:07am
Forum: Motor Technology
Topic: power stage using SMD and IMS
Replies: 10
Views: 2083

Re: power stage using SMD and IMS

another interesting design by infeinon ac motor driver for installing on 150mm Diameter motors
by ElectronS
Feb 21 2018 4:57pm
Forum: Motor Technology
Topic: power stage using SMD and IMS
Replies: 10
Views: 2083

Re: power stage using SMD and IMS

why donot you post some pics on your 3kw design and share your thoughts about the subject :)
and what is the unique custom design you are talking about :twisted: :mrgreen:
by ElectronS
Sep 30 2017 2:25pm
Forum: Motor Technology
Topic: Axiom: a 100kW+ motor controller
Replies: 414
Views: 88672

Re: VESC-controller

Hi

Great work ,

just a random question, what is the software you are using for designing the pcb , it looks awesome in 3D , much better than ALtium Designer 2016

cheers
by ElectronS
Dec 25 2016 11:42am
Forum: Battery Technology
Topic: Does a Lead Acid Battery exist with 1C or 2C discharge rate
Replies: 29
Views: 2551

Re: Does a Lead Acid Battery exist with 1C or 2C discharge r

The battery starting to look at is Westart. I know very little about them but look exciting. http://www.szwestart.com/ProductView.asp?ID=1065. I'm looking atthe 20ah grephene cell if I ca get it to fit ? wow this look HOT , i didnot know about this chemistry ... what is price of it ? lets say the 1...
by ElectronS
Dec 25 2016 5:27am
Forum: Motor Technology
Topic: Various types of dc motors for traction application
Replies: 9
Views: 1079

Re: Various types of dc motors for traction application

thanks for the valuable info guys .

maybe i am doing it wrong ( my calculations )

So how to choose a suitable motor and gearbox for a kart that weighs 800Kg maximum (with passengers) , top speed 65km/h , wheel diameter is 60cm , maximum incline 20 degree.

any rule of thumb ?
by ElectronS
Dec 25 2016 5:16am
Forum: Battery Technology
Topic: Does a Lead Acid Battery exist with 1C or 2C discharge rate
Replies: 29
Views: 2551

Re: Does a Lead Acid Battery exist with 1C or 2C discharge r

That's $1,000 for 48v 1,500 for 72v. Do you need the weight of lead ? No offcourse , any weight saving is a plus for sure . but i was just naming another good quality lead acid that i found , if someone would want it for general use. As for me i am back considering lithium , searching for cheapest ...
by ElectronS
Dec 24 2016 7:59am
Forum: Motor Technology
Topic: Various types of dc motors for traction application
Replies: 9
Views: 1079

Re: Various types of dc motors for traction application

Chances are you're over-thinking this. While there are advantages to each type of motor, they're going to be small given the application. Regardless of type you need enough motor to do the job when appropriately geared, so think torque and speed requirements to give the performance you want for you...
by ElectronS
Dec 24 2016 4:52am
Forum: Motor Technology
Topic: Various types of dc motors for traction application
Replies: 9
Views: 1079

Various types of dc motors for traction application

i am doing a research on which motor is better suited for Small EV or kart conversion using a fixed gear (single stage). the options available are : PMDC , SepEx , Series , BLDC . ( No ac motors ) I have found so many information regarding BLDC motors and their advantages , but no useful info on the...
by ElectronS
Dec 23 2016 2:47pm
Forum: Battery Technology
Topic: Does a Lead Acid Battery exist with 1C or 2C discharge rate
Replies: 29
Views: 2551

Re: Does a Lead Acid Battery exist with 1C or 2C discharge r

thanks for the input guys , this was really helpful , and i have also received a recommendation for optima batteries , if anyone is also interested

http://www.robotmarketplace.com/products/optima.html
by ElectronS
Dec 20 2016 12:20pm
Forum: Battery Technology
Topic: Does a Lead Acid Battery exist with 1C or 2C discharge rate
Replies: 29
Views: 2551

Does a Lead Acid Battery exist with 1C or 2C discharge rate

as the title suggest , i want a 72v or 48v (100A-to 200A) battery pack that i can safely continuously discharge at 1C or 2C , ( 200A ) for ME1004 or ME1003 motor .... i know that Lifepo4 or lithium ion can do that , but they are expensive and i donot need the long cycle life ( 50 -100 cycles are eno...
by ElectronS
Dec 03 2016 10:39am
Forum: Motor Technology
Topic: Micro Lebowski Controller - DIY 3kw
Replies: 496
Views: 52538

Re: Micro Lebowski Controller - DIY 3kw

have you thought about heat-sinking (active or passive) and how that will be connected to your PCB ? I would recommend for PCB design in altium to use 3Dcontinental or similar website to find 3D step files (for free) for your components and then use them in your library which is very easy and simple...
by ElectronS
Dec 01 2016 10:04am
Forum: Motor Technology
Topic: power stage using SMD and IMS
Replies: 10
Views: 2083

Re: power stage using SMD and IMS

Are they using aluminium substrate?. I just read 30oz copper. Oh yeah... chunky :twisted: I'll finish my layout and post it on my 3kw micro lebowski thread. I wonder how much these fets cost I haven't looked at them yet? Anyone have a link to a supplier You have not read it correctly , it is 3oz or...
by ElectronS
Nov 30 2016 4:16pm
Forum: Motor Technology
Topic: power stage using SMD and IMS
Replies: 10
Views: 2083

power stage using SMD and IMS

Anyone has considered building a high current (above 200A-400A at 48v or 72v ) power stage using SMD mosfets or IGBTs in to-263-7 package or TO-leadless (ex:IPT020N10N3) Using an IMS (aluminum substrate board) does help greatly in heat transfer and easy connection to an external heatsink. something ...
by ElectronS
Sep 08 2016 8:52am
Forum: Motor Technology
Topic: Anyone owns or Tried a Curtis 1229 PMDC controller
Replies: 0
Views: 274

Anyone owns or Tried a Curtis 1229 PMDC controller

Curtis have presented since last year their beefest and best in class PMDC controller for 48v systems. the 1229 model link :http://curtisinstruments.com/?fuseaction=Products.home#/product/66 before i buy it , (around 500$) i would like to know if it is a good product and if the new features are real...
by ElectronS
Apr 26 2015 5:11pm
Forum: Motor Technology
Topic: Lebowski's motor controller IC, schematic & setup, new v2.A1
Replies: 1819
Views: 222156

Re: Lebowski's motor controller IC, schematic and setup manu

sorry for the odd question
do you depend on this project for your income ? if No

when are planning on making the source code public ? or never !!

thanks
by ElectronS
Apr 26 2015 4:43pm
Forum: Motor Technology
Topic: Open Sensorless BLDC controller
Replies: 197
Views: 79141

Re: Open Sensorless BLDC controller

great work walls99
it works good and looks good too :)

you mensioned several times in your post something about the latest version of the code , can you send to me or just publish it , even if it is not ready , i am intersted in the current sense and sync with PWM + PI control OF TORQUE

regards
by ElectronS
Jun 24 2014 10:54am
Forum: Motor Technology
Topic: undervolting sepex motor possible ?
Replies: 2
Views: 392

Re: undervolting sepex motor possible ?

thank u , i appreciate your help , i will try and see
by ElectronS
Jun 24 2014 5:47am
Forum: Motor Technology
Topic: undervolting sepex motor possible ?
Replies: 2
Views: 392

undervolting sepex motor possible ?

i found in junk yard an old separately excited dc motor and i want to use this motor in a project and i was wondering if i can run it with lower voltage than the rating because i cannot make battery pack that big . Rating (3kw , 200v ) desired operating voltage 72v or possibly lower 48v ?? (offcours...
by ElectronS
May 22 2013 4:39pm
Forum: Motor Technology
Topic: Brushed motor controller circuit
Replies: 3
Views: 805

Re: Brushed motor controller circuit

with the type of motor , anything less than OSMC (open source motor controller ) is not going to work . i have read about some students desiging a robot with 2 of these and have used highest roboteq controller with no sucess ! that finally used a design similar to OSMC modified for double current an...