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Electronics => Electronics => Topic started by: owk on May 25, 2011, 01:51:45 PM

Title: DIY DC motor Controller
Post by: owk on May 25, 2011, 01:51:45 PM

I was wondering if anyone has eagle cad schematics for a  DIY dc motor controler for high voltage high amp motors? I found a link http://reprap.org/wiki/DC_Motor_Driver_1_1 (http://reprap.org/wiki/DC_Motor_Driver_1_1) showing a simple dc motor controller , can this be modified for the heavier loads?

Title: Re: DIY DC motor Controller
Post by: owk on May 25, 2011, 01:53:42 PM

I should have mentioned that i would like to provide a pwm signal to the motor controller from a RC rx, so how can this be done , or do you know of anything out there that can handle this?

Title: Re: DIY DC motor Controller
Post by: Razor Concepts on May 25, 2011, 01:59:36 PM

Could you specify voltage and amps?

Title: Re: DIY DC motor Controller
Post by: owk on May 26, 2011, 08:31:01 AM

12v and lets say something around 40A

Title: Re: DIY DC motor Controller
Post by: rbtying on May 26, 2011, 09:25:12 AM

Use an RC ESC - they're best suited to what you're trying to do, I would think.  That kind of current isn't something you want to mess around on.

If you really want to DIY it, you'll need power MOSFETs in a full H-bridge configuration, instead of the dedicated ICs on the schematic you posted.  They can only handle .75A, after all.

Title: Re: DIY DC motor Controller
Post by: owk on May 26, 2011, 09:29:59 AM

I need to get bidirectional control is there a way to mod an ESC so that i can get that control?

Title: Re: DIY DC motor Controller
Post by: garrettg84 on May 26, 2011, 10:00:18 AM

Quote from: owk on May 26, 2011, 09:29:59 AM

I need to get bidirectional control is there a way to mod an ESC so that i can get that control?

Most RC ESCs today are actually for brushless motors (essentially they are AC motors...). A straight DC motor controller could be made out of the RC ESC if you could hack the firmware and it would definitely have the capability of running bidirectional. They typically power brushless motors with 3 leads and the ESCs contain 3 half h-bridges. So you would actually have a spare half-h per ESC you modded. Most of the hobbyking ESCs also have AVR controllers on them, so if you are familiar with Atmel ICs then this should be simple.


There are a few pages I'd found in the past about hacking some of the hobbyking brand ESCs and turning them into DC controllers.

Title: Re: DIY DC motor Controller
Post by: owk on May 26, 2011, 10:43:15 AM

i would really appreciate if you have nay links to open source code of a hacked esc , im still a beginner at all of this, much appreciated

Title: Re: DIY DC motor Controller
Post by: garrettg84 on May 26, 2011, 11:13:20 AM

This is what I had found previously:
http://www.robowars.org/forum/viewtopic.php?p=66515 (http://www.robowars.org/forum/viewtopic.php?p=66515)
http://www.robowars.org/forum/viewtopic.php?p=68066#68066 (http://www.robowars.org/forum/viewtopic.php?p=68066#68066)

Title: Re: DIY DC motor Controller
Post by: cyberfish on May 27, 2011, 09:30:13 PM

At 40A, IGBTs may be more efficient than MOSFETs.