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Electronics => Electronics => Topic started by: hendrachubby on March 14, 2009, 07:10:22 AM

Title: DC Motor Braking
Post by: hendrachubby on March 14, 2009, 07:10:22 AM
Hello,
I'm now trying to control a dc motor, but if i stop the motor it just free and can't brake.
Anyone can help me to explain how to brake a dc motor using motor driver ? can i do it with any motor driver ?
Title: Re: DC Motor Braking
Post by: chelmi on March 14, 2009, 08:57:47 AM
Hello,
I'm now trying to control a dc motor, but if i stop the motor it just free and can't brake.
Anyone can help me to explain how to brake a dc motor using motor driver ? can i do it with any motor driver ?


Usually you have to set the two direction input pins of your motor controller to high:
http://itp.nyu.edu/physcomp/Labs/DCMotorControl#toc6 (http://itp.nyu.edu/physcomp/Labs/DCMotorControl#toc6)

I you use a classic H-Bridges chip (L293 or SN754410) this should work.

Chelmi.
Title: Re: DC Motor Braking
Post by: hendrachubby on March 14, 2009, 10:53:43 AM
Is it work with any DC motor ? Is the same method with shorting the 2 terminal of motor causing it brakes ?
Title: Re: DC Motor Braking
Post by: chelmi on March 14, 2009, 11:38:12 AM
Is it work with any DC motor ? Is the same method with shorting the 2 terminal of motor causing it brakes ?

I would think so. What DC motor do you have ? What do you mean by "shorting the two terminal of motor?"
Title: Re: DC Motor Braking
Post by: hendrachubby on March 14, 2009, 12:28:11 PM
I use sanyo denki DC motor, i try to connect the terminal of the motor and turn the motor with hand, i feel the motor brake acting like a generator i think.
Title: Re: DC Motor Braking
Post by: want2learn on March 14, 2009, 01:28:52 PM
Yes you can brake a dc motor by 'shorting' both motor terminals together although braking with an h-bridge holds the motor better
Title: Re: DC Motor Braking
Post by: Soeren on March 15, 2009, 06:02:13 AM
Hi,

Yes you can brake a dc motor by 'shorting' both motor terminals together although braking with an h-bridge holds the motor better
How's that???
Shorting the terminals is close to zero Ohm, shunting it with an H-bridge adds two R_ds_on to the equation!
Title: Re: DC Motor Braking
Post by: Webbot on March 15, 2009, 02:47:53 PM
You've said which motor you are using but what controller are you using?

Some controllers (like my designs in the member pages) - use a tri-state switch to switch between forward/reverse/brake.