high rpm(500-1000) stepper motors...

[Shashijain]

i have heard that rmp of stepper motor can be varied from few rmp to 10,000rmp!!...
bt the problem occurs when duration of pulse become less then the response time of the coil...

can anyone help me how to increase the rpm of stepper motor???

or is there any special stepper motor whos rmp can b varied upto 10,000rmp??

or no. of poles increases the rpm???

remmember i have to use 12-15 volts only.....

 

[FvM]

High step frequencies are achieved with low inductance motors in constant current mode.
Typical driver supply voltages are up to 100 V.

 

[Prototyp_V1.0]

remmember i have to use 12-15 volts only.....

This could be the restricting factor here.

To increase speed to a stepper over a certain level (depend on model), voltage have to be increased.
This is in order to be able to feed the stepper with enough current.

Another possible problem could be the rating of the stepper. Would it sustain such high speed?

 

[Shashijain]

is there any effect of no. of poles on the maximum step frequency???

 

[Prototyp_V1.0]

is there any effect of no. of poles on the maximum step frequency???

Frankly I don't know.

But I've made up some thaughts.

If stepper motor is driven only by a set of basic H-bridges, wich mean voltage over coils can be just on or off, I guess that greater number of poles could lead to shorter spikes/frequency when rpm remains the same as for a regular motor.
But I have to admit that I doesn't have any experience with steppers with 5 poles or more.

I beleive a multipole stepper can be set up in different ways. t.ex a configuration will allow it to run without any H-bridges. Regular transistors in open colector configuration will do the job. In such a configuration, any pulse should have shorter duration than on a similar regular stepper when rpm is the same.
However, the logic driver circuit (or program) still may allow multiple coils being active in same time.

So bottom line is: I think there is no "yes" or "no" answer on that question, because what matters more than number of poles is how the driver circuit is set up. I guess a DAC on each input to the stepper (very sophisticated driver) may be the way that allow the stepper to run fastest of all methods. In theory it will alow the stepper to move smoothly from one step to another.
However, a 7-pole stepper compared to a 4-pole stepper is possibly designed for better precision, that is smaller steps.