Modulators - Inductive adder. Technical description. Turn-on AND Turn-off Capability – hence PFN/PFL is NOT required: instead Capacitors are used to store energy; Excellent scalability; Output pulse can be modulated; BUT: pulse length is limited by saturation of magnetic material…. n-layers Output = n x voltage per layer Turn on/off: MOSFETs or IGBTs Magnetic coupling 𝐴 c pulse capacitor SC-switch 𝐼 sec Stalk (secondary) stacked layers magnetic core 𝐼 prim primary winding insulation parallel branches PCB

Modulators - Inductive adder. Overview summary. Goal Thyratron/PFL replacement Timescale to possible deployment Medium term for CPS (~4+ years?) Long term for FCC/CLIC Gains w.r.t. present technology Increased reliability and reduced maintenance – expected to have good fault tolerance Modularity Solid state switches (presently risk with single-source thyratron supplier) Short delay (~200ns) for turn-off of magnet field (c.f. clipper and especially dump switches) High precision possible High stability Possible deployment scope CPS systems for short pulses (<3us pulse) – around 20 generators across 10 systems Ongoing activity domains - projects and present resource levels CLIC DR [1 PJAS, 0.1 STAFF] FCC low impedance [~0.7 FELL, 0.1 STAFF] KFA45 generator replacement [~0.3 FELL] – no budget at present Present status and outlook CLIC prototype tested at 6.3 kV, 1 µs, 125 A (voltage being increased). FCC prototype under construction: Measurements in coming 12 (and 24 months) Section Involvement BTP X EC Xx EDS XX KSC PPE XXX SE

Modulators – Marx Generator. Technical description. Marx generator concept: n capacitors charged in parallel by relatively low voltage power supply Udc, through diodes Dc and switches Tc. Subsequently switches Tp connect all capacitors C in series with the load, applying approximately nUdc. For fast rectangular pulses MOSFET technology is required. Load voltage: 3.2kV across 1.2Ω. 60ns rise, 30ns fall Turn-on AND Turn-off Capability – hence PFN/PFL is NOT required: instead Capacitors are used to store energy; Excellent scalability; No magnetic material to limit pulse length (but droop of capacitor voltage); Reliability (single point failure) needs careful investigation.

Modulators – Marx Generator. Overview summary. Goal Thyratron/PFL replacement Timescale to possible deployment Medium term for CPS (~4+ years?) Long term for FCC/CLIC Gains w.r.t. present technology Increased reliability and reduced maintenance – fault tolerance to be studied Modularity Solid state switches (presently risk with single-source thyratron supplier) Short delay (~200ns) for turn-off of magnet field (c.f. clipper and especially dump switches) Possible deployment scope CPS systems for short pulses (<3us pulse) – around 20 generators across 10 systems Ongoing activity domains - projects and present resource levels FCC/CLIC/KFA45 [<0.1 FELL, 0.1 STAFF] (Collaboration with ISEL & EPS) Possible collaboration with ETHZ (best technology to be identified  not necessarily a Marx) Present status and outlook Measurements on “low” (~3kV) voltage, but nominal current, ongoing – test @ CERN Prototype with KFA45 specifications in design (but terminated load) Section Involvement BTP X EC EDS KSC PPE XX SE