how to soften bldc motor start up

[etiquoe]

hi..
i'm still working on my sensored bldc motor driver.
i need a solution to make my bldc motor start up softer.
i'm using open loop speed control method.
and one more problem is at above 50% duty cycle no start up failure occur, but at below 50% duty cycle the bldc motor start up often failed.

anyone help please

regards.

 

[srizbf]

if the motor fails below 50%, it may be due to the supply voltage is not proper value.