How do I know this circuit makes sense and will work when implemented in a breadboard?

[Vivek405]

Hi all!


I am new here, so please guide me. I am currently working on a project which involves working with H-bridges for motor control. It is required that I am able to wire up the circuit and make it work. The only problem is that I am a Mechanical Engineering student, so I have no knowledge of how this circuit is supposed to work. Since it was passed on to me by the previous year students who are no longer working on this project, I have no way to confirm what is happening in the circuit.


The circuit is attempting to create 3 phases (A, B and C) to run a BLDC motor using 3 H-bridges, and while I understand the concept of what is supposed to happen, I am confused as to why it doesn't work in real life when plugged in. Could someone please advise if the circuit is correct, what is happening inside it and whether it will work as intended when plugged in to a breadboard, since I have tried wiring everything up exactly as specified and it didn't work (I know that the N-channel MOSFETs are not fried)?

Thank you!

 

[3DDave]

You are missing the part that enables the phases in the correct order. This is typically done with a microcontroller that uses some feedback from the motor to understand the rotor position.

For exsmple:

https://www.circuits-diy.com/how-to-build-a-3-phase-brushless-bldc-motor-driver-circuit/

The part you showed is the right hand part of the circuit I linked to. You need the microcontroller.

Similar

https://www.allaboutcircuits.com/in...brushless-dc-motor-control-with-hall-sensors/