hias9 said:
Here is a little video: https://files.fm/u/ngq4xbax2
The frequency is the switching frequency of the controller.
In this video, some torque is commanded to the motor by slightly engaging the throttle, but I hold the bike with the brake so it's not turning and hall is not changing state.
The hall I am measuring is always enabled throughout the entire video.
The video only raises more questions. If you will answer the specific questions previously posted, and test those things suggested, and then answer the questions in this post, it will help us understand your test setup and the specific problem.
By "enabled" do you mean activated by a magnet?
If so, it will be in grounded state, not near 5v. Near 5v is the
deactivated state of an open-collector hall sensor.
If it is actually in a grounded state, then the problem is far worse.
Regarding the oscilloscope display, since you haven't stated how you have it setup, I have to make assumptions based on scopes I've used. If they are wrong, please describe exactly how you have it setup--if you don't, we can't know what is actually being displayed, which means we can't know what signal you are actualy seeing (whether it is tiny riding on the supploy, or huge beyond full scale of the supply, or something between).
It shows 5v on the bottom corner. If that is 5v / division, and the centerline with the arrow on the left edge is 0V, then the signal you are seeing is about 10v or more in swing from highest peak to lowest peak, and is about 12-13v nominal. This means that your pullups in the controller are not supplied by 5v, but probably 12v or 15v, which should be enough to increase the signal-to-noise ratio to help the controller read the signal under normal conditions.
But a swing of 10v is huge, and indicates a need for physical and/or electrical (shielding) isolation of the hall wires from the phase wires, as the currents in the phase wires are so high that they are inducing currents in other nearby wires (like the hall signals, and probably also in their power and ground wires, which will affect the actual hall operation).
If the hall should be in a grounded state, and it is reading 10v swings around a 12-13v level, either the hall has actually failed and is no longer able to ground the signal line when active, or else there is a high enough resistance between the point you're measuring and the hall itself that the voltage developed across that resistance by the induced currents from the motor phases is causing the problem.
If it is really this bad of a noise problem from phase-current induced currents in other wires, you may even want to isolate the phase wires from *each other* as they will induce currentsinto each other that might affect the controller's own monitoring of the phases, if it does any, and it's control of the motor.
Does the same kind of problem happen when letting the motor freely spin under a normal load (like when riding, or with a dyno-type load if you can set one up), as it does with a locked rotor like this?
Does the same kind of problem happen when the motor phases are disconnected from the controller and the same test is performed? (so that there is no current in the phase wires and thus no induced currents in the hall signal lines) If so, there is a problem inside the controller itself you would need to trace down, to find the source of the interference signal that is making it's way into the signal lines.
Same applies to using a hall sensor directly connected to the controller PCB with all of the hall signal wires removed from the PCB (as suggested in my previous reply).