I have an 8A choke used to filter a DC power line. It's big. It could be smaller if I used a permanent magnet to bias a nominally 4A choke to the equivalent of -4A.
Tricky in practice, especially with a toroidal core.
Will an iron powder core become permanently magnetised if I hit the choke with enough (reverse) current? If so, how much is enough?
Cheers