# Difference between permanent magnet and electromagnet exciter generator in principles wise?

I searched about this, but couldn't find any helpful explanations. All it says is that magnetic field is generated by either permanent magnets or electromagnets. In both cases, how does the exciter generator start, so that it creates magnetic field according to physics, (e.g. Lorentz law, or another) ?

• Hi, I'm having problems understand your question! Is this about the DC motor-generators? What do you mean by exciter? Dec 22 '18 at 21:40
• I am new to the subject, that might be the reason. I guess the ones with permanent magnets are DC, and electromagnets are AC. I want to understand how exciter generators actually work, so that the AC or DC powered generator can start. Simply, I want to learn the principle of exciter generators (how they get started, and how they excite)
– Vyun
Dec 22 '18 at 23:10
• The excitation winding is a part of stator in DC machines which produce the constant magnetic field, every conductor carrying current generates a magnetic field around itself that's how an electromagnets works a very very simplified version. But i don't understand where the problem lies? How AC induction or DC-machines works are actually the very comprehensive theory, i'm afraid i can't explain it here, because i don't know how much you know about electromagnetism, but if you have still question about specific type of AC or DC machines i would glad to help, sure others try to collaborate. Dec 22 '18 at 23:16
• So, all generators actually initially produce AC current? In principle, if what generator is transforming mechanical energy to electrical energy, I just do not understand what role the exciter generator takes.
– Vyun
Dec 24 '18 at 22:34