Pulse train skip one cycle

[marce002]

i would like to hear anothers opinions since im not going to interfere with the sensors ... im just telling the controller that speed is half.

[langwadt]

i would like to hear anothers opinions since im not going to interfere with the sensors ... im just telling the controller that speed is half.

speed is not the purpose of the sensors, the purpose off the sensors is to tell the controller when and how to drive each coil of the motor that is why there is three of them

[marce002]

I need to explain that this motor does not have speed sensor nor magnets so the speed computation is with hall sensors.. it is very common... now i just want to div by 2 the freq of the pulses without interfering with phase wires...

[Ian.M]

I agree with Langwadt and DavidAlfa.  The controller uses the three hall sensor signals to generate the timing for the phase sequence driving the coil wires.  If you halved the pulse rate from each sensor the phase sequence frequency would also be halved, and would no longer be synchronous to the rotor,  resulting in rapid deceleration of the motor if its spinning or failure to start if not.   Also most controllers would detect a sensor fault and error out.

The *ONLY* option that could achieve more speed from your existing controller would be if its firmware can be reconfigured to increase the controller's max. RPM limit and remap its throttle response.  Even if you have the controller's configuration utility, this is unlikely to be possible for a factor of two speed increase if the firmware is closed source.

[langwadt]

I need to explain that this motor does not have speed sensor nor magnets so the speed computation is with hall sensors.. it is very common... now i just want to div by 2 the freq of the pulses without interfering with phase wires...

it doesn't need a speed sensor, it can use the hall sensors that are already there to control the coils. The motor almost certainly have magnets. you can't do anything to the hall signals without messing up how the phase wires are driven

[marce002]

PAOPBZ?

[PA0PBZ]

PAOPBZ?

All I know is that you asked in your first post: how to halve the frequency of the pulses. You didn't specify where these pulses came from or where they were going to so I showed you how to do a divide by 2. I have no experience with motor controllers so I can't comment on the information that was added later. If more experienced members say that you can't do what you are trying to do I accept that.

[EPAIII]

Any circuit that you put in the path will have some delay: it is just a matter of how much. So, unless you want to deliberately introduce a full, one cycle delay, it will not be "exact".

You may want to think a bit more about just what is really needed and formulate your requirements in a more precise manner.

but i need to not affect the bldc motor feed to coils, so the timming should be exact. I need to send identical pulses to the controller like the original pulse train, so the motor coils do their job, but only affecting the amount of pulses (sending less pulses) , so the controller will speed up the train because the input is a lower speed wheel

[EPAIII]

Perhaps if you gave us more information about the exact motor and controller board you will be using, then better advise could be had. Designing a motor control scheme can be tricky.

Or provide as much info as you can cobble together at this stage in your design process.