Irregular output from DC Motor used as a generator?
It seems like you have a loose connection somewhere. With magnet wire, you need to carefully scrape the varnish off the surface of the wires, twist them together and solder them. The voltage A to neutral trace shows the voltage jumping up and down. That must be the result of a loose connection. The scope patterns seem to be inconsistent with one another. It appears that moving the scope probes may move the wires so that the connections change.