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Electronics => Beginners => Topic started by: Adrian_Arg. on February 19, 2023, 12:15:34 am

Title: hard drive engine
Post by: Adrian_Arg. on February 19, 2023, 12:15:34 am

I have a question, I have several hard drive motors, but all with three pins, and the schematics that I have seen are for four cables, using irfz44n, in those with three cables, what would be the correct schematic?

Title: Re: hard drive engine
Post by: DC1MC on February 19, 2023, 12:19:05 am

https://www.electroschematics.com/hdd-bldc-motor/ (https://www.electroschematics.com/hdd-bldc-motor/)

Is three-phase engine, maybe triangle connection:
https://www.youtube.com/watch?v=WDrRPRUpvgg (https://www.youtube.com/watch?v=WDrRPRUpvgg)

Title: Re: hard drive engine
Post by: Whales on February 19, 2023, 02:26:13 am

At a vague guess:

4 wires = 2 coils
3 wires = 3 coils in a "delta" or "wye" "3-phase" configuration

Title: Re: hard drive engine
Post by: Doctorandus_P on February 19, 2023, 09:13:47 am

The video linked to by DC1MC also uses a 4 wire connection, but with 3 MOSfets. This suggest a Y conncection for a 3-phase motor.

If you only have 3 wires, then you need three half bridges instead of 3 MOSfets. The motor itself is just a BLDC motor, and any motor controller that can do sensorless drive for a 12V motor should work.