- #1
XZ923
- 136
- 63
Hello all, first time posting here. Just to give a quick background, I'm NOT an electrical engineer; I'm a motorsport mechanic by trade. However, in the motorsport world electrical work typically doesn't go beyond "start replacing parts and see where it goes", so I try to learn as much as I can because I actually find it interesting. I have a question regarding three-phase stators that will probably be easy for you guys.
In a system using a permanent magnet alternator, the stator does not have a ground or a neutral. My understanding is that if there is a neutral lead off the wye connection of a wye-wound three-phase stator it should hold that phase-to-phase voltage=phase-to-neutral*the square root of 3, ie if the phase-to-phase is 50 ACV the phase-to-ground (yes I am aware I'm using neutral and ground interchangeably here, I'll get to that in a second) should be ~28.866 ACV. And that is what you get when you measure phase to chassis ground. But here's my question: the stator doesn't have a neutral off the wye OR a ground connection, it's just the three AC output leads! If you measure phase-to-ground resistance it's an open line, but if you measure phase-to-ground ACV you get essentially what you would get with a neutral line off the wye. Can someone explain why this is? I'd appreciate it.
In a system using a permanent magnet alternator, the stator does not have a ground or a neutral. My understanding is that if there is a neutral lead off the wye connection of a wye-wound three-phase stator it should hold that phase-to-phase voltage=phase-to-neutral*the square root of 3, ie if the phase-to-phase is 50 ACV the phase-to-ground (yes I am aware I'm using neutral and ground interchangeably here, I'll get to that in a second) should be ~28.866 ACV. And that is what you get when you measure phase to chassis ground. But here's my question: the stator doesn't have a neutral off the wye OR a ground connection, it's just the three AC output leads! If you measure phase-to-ground resistance it's an open line, but if you measure phase-to-ground ACV you get essentially what you would get with a neutral line off the wye. Can someone explain why this is? I'd appreciate it.