Re: MOT Charging reactor

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "S&JY" <youngsters-at-konnections-dot-net> 

James,

Some time ago I experimented with using MOT secondaries for my DC resonant
charger reactor.  I ran 4 of them in series which worked well.  I didn't
remove the shunts, and power was around 1 KVA.  Total inductance was 40
Henry or so.     I used this with both an RSG and a high velocity TSG.
Neither approach was totally satisfactory.

I also took apart one of the 4 MOTs to add an air gap, and it didn't make
enough difference to be worth the bother.  But if you insist . . . it takes
about 10 minutes to hand hacksaw through the two welds and pop off the I
core section from the E main core.  Fortunately, MOT cores are not
interleaved.

I abondoned this approach and now use a small air core reactor (140 mH) to
resonant charge the tank capacitor through one set of RSG gaps, then
discharge the cap through the primary through another set of RSG gaps.
Works much better for me and avoids power arcs when your RSG dwell time get
too long at lower RPMs, or you crank too much power through your TSG.
--Steve Y.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, September 01, 2004 4:16 PM
Subject: MOT Charging reactor


 > Original poster: "James Robinson" <james.robinson-at-vistek.tv>
 >
 > Hi all,
 >
 > This is my first post to the list, so hello all!
 >
 > I am in the process of building my second coil, which will be a DC
supplied
 > system, utilising reactive charging of the tank capacitor.  I have a big
 > pile of old MOTs, which I am considering some of for the reactor.  What I
am
 > wondering  is, how easy it is to disassemble an MOT core (for the purpose
of
 > inserting an air gap) - I assume the laminations are interleaved, so I
 > figure even once the welds are removed, its not going to be the easiest
task
 > to separate all the laminations and re-orientate them into solid E and I
 > sections (the whole thing is covered with resinous gloop).  I would
ideally
 > like 6 inductors - so this could be quite a lot of work!
 >
 > Any tips from someone who has tried it before would be greatly
appreciated.
 > Otherwise has anyone found another source for such a beast of an inductor!
 >
 > For reference, I anticipate running 1-2kW through the system from an MOT
 > based "stiff" DC supply. The switching mechanism will be a TSG
incorperating
 > magnetic + high velocity air quenching - hence the need for some prety
 > serious HV current limiting!
 >
 > James Robinson
 >
 >
 >