BLDC control issues spinning

[Benn Ng]

Hi guys,

i am using micro controller arduino uno to produce 3 phase PWM pulses by using DDS method available online.

the PWM pulses will be fed into a diadem circuit to provide diadem for accidental turn on of each pair of mosfet(3pair for 3 phase)

each PWM generated will be fed into a inverter to produce a complentary signal of each other.

PWM1 = PWM1A(high logic),PWM1a(low logic)
PWM2 = PWM2A(high logic),PWM2a(low logic)
PWM3 = PWM3A(high logic),PWM3a(low logic)

each pair of PWM will be fed into ir2110(mosfet driver to drive h bridge)

with each pair of PWM into each driver, the ac signal from each mid point of a pair of mosfet will be used to drive the BLDC

BLDC used is MT2826 from rctigermotor. not sure how this motor current rating or power rating works.

DC link for H bridge is 15V,3A since power is 45W

control circuitry are using 5V,15V isolated but all circuitry are using common ground.

but the BLDC only have the zzzz sound but is not spinning or moving at all?

please advise. thanks you

attached is the AC signal output from 3phase h bridge

 

[chuckey]

Because of the inertia of the rotor of your motor the speed of your waveform must start slow and speed up to the running frequency.
Frank

 

[Benn Ng]

hi chuckey, i started of using a dc link of 15V ,3A power supply. the current remain as 3A but starting at 0V and slowly increase by 1V until it reach 15V but it still have that zzz sound instead of spinning properly.

the power supply generator at 15V 3A show a constant current and constant voltage instead of preset values.

please advise.

 

[srizbf]

Hi guys,

i am using micro controller arduino uno to produce 3 phase PWM pulses by using DDS method available online.

the PWM pulses will be fed into a .......

your description didnt have any info on the feedback pulses from bldc.(hal sensor)

did you sense it and control the bldc?

- - - Updated - - -

and if sensor signals are used , one possiblity is the interchange of feddback wires , which may result in the zzzz sound.

 

[Benn Ng]

Hi, my motor are sensor less. I intend to try changing the order of the motor U v w. Maybe the buzzing sound happen because the order is wrong? Maybe u w v . Possible chances?

 

[srizbf]

Hi, my motor are sensor less. I intend to try changing the order of the motor U v w. Maybe the buzzing sound happen because the order is wrong? Maybe u w v . Possible chances?

yes.
it is U,V,W.

 

[Benn Ng]

i have research on that u v w or u w v. changing the wires only affect the direction of it spinning like cw or ccw.

i have tested on a small load motor . but only when at a particular analog input will the motor spin but once out of the particular analog control. the motor stop spinning and buzzing sound occur.

i would like to seek help in ensuring that my ac output waveform are correct that could be fed into the bldc. if the waveform are correct. that only thing to consider is the power supply to be higher.

thanks

 

[srizbf]

i have research on that u v w or u w v. changing the wires only affect the direction of it spinning like cw or ccw.
..............
thanks

did you follow the sensorless control methodology in your control algorithm?