What type of motor would have the highest Stalled Torque?

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Sergio Trigos
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I am referring to the output torque of an electric motor when the rotational speed of the rotor is 0 RPM. Some sources say that having a stalled torque damages some motors, and I know that some motors have a constant torque regardless of their speed while others have a max torque at 0 RPM. So If I need an electric motor that can create a decent torque while stalled, which type of motor would be recommended? regardless of weight, size, price, and complexity.

Also if you have a source where I can find torque to speed graphs for the different types of electric motors, that would also be very helpful.
 
on Phys.org
Welcome to PF.

Traction motors are designed to move things starting from a dead stop.

https://en.wikipedia.org/wiki/Traction_motor

Edit:
Also if you have a source where I can find torque to speed graphs for the different types of electric motors, that would also be very helpful.

I just go to images.google.com and search for a term like "traction motor speed torque curve" Substitute any other kind of motor you want.
 
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Sergio Trigos said:
Also if you have a source where I can find torque to speed graphs for the different types of electric motors, that would also be very helpful.
Check motor manufacturer websites such as Baldor, Siemens, ABB, Leeson, Marathon, etc.

You may find this and related articles from the Plant Engineering site useful for general information on motor selection.
 
Brushless DC servomotors can run at full torque all day at zero RPM. Allen-Bradley and Siemens are two well known manufacturers. Here's a link to A-B: http://ab.rockwellautomation.com/Motion-Control/Rotary-Motors. Their MP series are very commonly used.
 
For maximum stall torque, a separately-excited DC motor, then a series-wound DC motor. Next would be the equivalent AC motors. They are both limited only by the amount of iron in them and the wire size (assuming a sufficient power supply. :smile:)
 
A NEMA Design D induction motor has its highest torque at 0 RPM. It is designed for high inertia loads. And, since it's an induction motor, it does not have brushes nor does it need a drive. Here's a good discussion about the various classes of induction motors: http://industrialelectricalco.com/wp-content/uploads/2014/01/nema-abcde-torque-curves.pdf.
 
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Sergio Trigos said:
I am referring to the output torque of an electric motor when the rotational speed of the rotor is 0 RPM. Some sources say that having a stalled torque damages some motors, and I know that some motors have a constant torque regardless of their speed while others have a max torque at 0 RPM. So If I need an electric motor that can create a decent torque while stalled, which type of motor would be recommended? regardless of weight, size, price, and complexity.

Also if you have a source where I can find torque to speed graphs for the different types of electric motors, that would also be very helpful.
DC motor is one of the best choice to get the absolute most torque as compared to any other. Because its voltage phase and current phase are perpendicular to each other which gives a max absolute torque.
 
I think you might also look at motor with fewer turns and a gearbox. Fewer turns makes it faster with less torque. The loss of torque is recovered by using a gearbox. Some losses in the gearbox but reduced turns lowers winding resistance and increases stall current.
 
The OP has not told of the application. In some cases, replacing direct drive with hydraulics is a better solution than high torque motors.

Related:
https://en.wikipedia.org/wiki/Diesel%E2%80%93electric_transmission said:
A diesel–electric transmission, or diesel–electric powertrain, is used by a number of vehicle and ship types for providing locomotion.

A diesel–electric transmission system includes a diesel engine connected to an electrical generator, creating electricity that powers electric traction motors. No clutch is required. Before diesel engines came into widespread use, a similar system, using a petrol (gasoline) engine and called petrol–electric or gas–electric, was sometimes used.

Diesel–electric transmission is used on railways by diesel electric locomotivesand diesel electric multiple units, as electric motors are able to supply full torque at 0 RPM. Diesel–electric systems are also used in submarines and surface ships and some land vehicles.