Effects Of Fluctuating Dc Current On Dc Motor

[mega_processor]

I am not sure if this is the right section to post but i always think working ofac/dc motor comes under physics.

anyways i tried to run a 14W dc fan on 20W solar PV and it ran fine.But i remember basics how any fluctuating current can damage motor,be it ac or dc.

But i exactly want to know what damage this can do over a period of time?Is there any buffer circuit i can use to protect the dc fan motor from surge and fluctuating currents?

lets not talk about solar charge controller for now.i am looking for a simpler and cheaper solution.

[Geek]

If it's a universal AC/DC motor with brushes, no damage... just annoying slowdowns now and again

[mega_processor]

It is a bldc motor.ie brushless

[CWB]

the fan should suffer no damage from a drop of input voltage .
the worst case scenario is the fan stalling , but the electronics/windings will be ok with this .
a common trick to slow down a brush-less fan is to insert a resistor or string of diodes in the power lead (usually the "+" side) and thus drop the input voltage .

[mega_processor]

in a solar pV voltage drop is not steep but yes current can vary ridiculously at times.the fan is made in china and they claim its bldc but somehow i will be opening the fan soon to clarify things and will post pictures of it from inside.