Stepper motor driver voltage question
As long as you stay below the 2A, it will be fine.  This is a common misconception about voltage ratings on stepper motors.

The 3V refers to how much DC voltage you could apply to a coil continuously.  The coil resistance is probably about 1.5Ω, so if you put 3V DC across a coil it would draw 2A.

The stepper driver will be sending pulses, so you don't actually need to worry about the voltage rating.