Tool/software:
Hi,
I have a project which I am using TI DRV10970PWPR to drive my 3-phase BLDC motor specifically Minebea NMB BLDC 24P16A. Now when I applied PWM input signal to the driver with frequency of at least 15kHz as recommended by the datasheet, it causes my motor to behave badly. After 2 complete rotations, it rotate back a little or stop for some milliseconds. It will do that every 2 rotations.
However, when I used PWM input signal with frequency below 500Hz, it works well, at least up to 79% duty cycle for 200Hz, for example, or up to 49% duty cycle for 500Hz. Above those % duty cycle mentioned, the motor behaves badly similar to what I just described.
Anyway, I am ok to use PWM with frequency around 200Hz which is what i see as the optimum one based on my application and the duty cycle that I will use which is just up to 70% anyway.
My question now for TI is that is it ok that I am using PWM frequency that is way below the recommended frequency mentioned in the datasheet of TI DRV10970? What do you think is the consequence or ramification, if there is any?
Additional information is that I am running the motor with very very light load (a 50g disc of 38mm diameter and 10mm thickness) with just spinning it at constant rpm of 600 up to 900 and operating the motor at just 6V which is also the supply to the motor driver.
