DC motor as generator

[Peter_wadley]

When you spin a DC motor.. is the voltage generated AC or DC?

 

[Analog]

When you spin a DC motor.. is the voltage generated AC or DC?

What kind of DC motor? PM? Stepper? Etc?

 

[Peter_wadley]

Perm mag.. just a basic model DC motor.

Thanks

 

[kchriste]

You get pulsating DC.

 

[dknguyen]

You get pulsating DC.

Yup. THe same split- ring commutators in a DC motor that turn the DC current into AC (so the motor can actually spin and not lock-up) have the reverse effect on the AC generated when you spin the motor to make it behave like a generator.

 

[Nigel Goodwin]

Yup. THe same split- ring commutators in a DC motor that turn the DC current into AC (so the motor can actually spin and not lock-up) have the reverse effect on the AC generated when you spin the motor to make it behave like a generator.

Yes, the commutator and brushes form a mechanical rectifier - for those old enough to remember vibrator power supplys (used to power valve radios in cars), you could buy them with or without extra contacts for mechanical rectification of the HV output.