MKD stack upgrade MKD generator meeting Viliam Senaj 23/06/2015

Effect of return rod displacement RR displacement [mm]0 Present situation Inductance stack [nH] Inductance MKD total [nH] TeV [kV] Emax [MV/m] Trise increase [ns]

Solution with return rods displaced by 20 mm Return rod displaced by 20 mm Araldite insulation of RR Modified top insulator – upper tube included Reduced diameter of 4 upper HV deflectors and full insulation by araldite HV contact insulated by araldite Modified 4 top snubber capacitors – araldite tube around instead of HV deflectors

Solution with return rods displaced by 20 mm

Time plan Drawing of machining plans ~ 2 weeks Procurement of raw material for 3 switches ~ 2 months Machinning ~ 4 weeks Assembly ~ 3 days Test of single stack in HV case up to 40 kV ~ 1 week Test inside generator ~ 6 months

Magnet kV o vs 20 mm displacement (132 vs 165 nH)

Main dividers 2 x 100 MΩ

Main dividers 2 x 100 MΩ - solution

HV divider 10 x 5 MΩ, top deflector

HV divider 10 x 5 MΩ – solution

HV contact region - today

HV contact region - solution

Final solution

MKD E/B2 freewheel signal

MKD schematics