High Power Solid State Modulator Development at SLAC Craig Burkhart Power Conversion Department March 5, 2010
SLAC Development Team Richard Cassel (slide material) Minh Nguyen Ed Cook (LLNL) Craig Brooksby (NSTec) Page 2
Inductive Adder Topology Modules with transformer coupled output Primaries in parallel Secondaries connect in series Array low voltage IGBTs to 2x50ufd 2.5kv 1/3/1 E Q1 generate high voltage pulse G C3 C 130ufd 150v IGBT DRI C1,2 D1 3kv 3.3Kv 800A T All components at near ground potential Single turn (or few turn) transformers have high bandwidth Fault tolerant E G C IGBT DRI E G C IGBT DRI E G C IGBT DRI E G C IGBT DRI Page 3 Q1 3.3Kv 800A Q1 3.3Kv 800A Q1 3.3Kv 800A Q1 3.3Kv 800A 130ufd 150v C1,2 130ufd 150v C1,2 C1,2 C1,2 C3 D1 3kv 2x50ufd 2.5kv 130ufd 150v C3 D1 3kv 2x50ufd 2.5kv 130ufd 150v C3 D1 3kv 2x50ufd 2.5kv C3 D1 3kv 2x50ufd 2.5kv 1/3/1 T 1/3/1 T 1/3/1 T 1/3/1 T
SLAC Induction Modulator Program 1. XP(8-Pack): Driving eight PPM klystron (XP) 500kV 2000A (500MW RF) 1.6 µsec 120 Hz for RF Program. (XP klystron did not get manufactured) 2. XL4(4-Pack): Driving four XL4s using one half the drivers 400kV 1260A (200MW RF) 1.6 µsec 30-60 Hz for RF Testing. (Operated) 3. DFM (Design For Manufacturing) (8-Pack): Design a prototype, to Drive 8 XP klystrons (Program change klystron reduced to 2 Klystrons per modulator) 4. DFM1 (Hybrid 2-Pack): Build a DFM prototype 15 stack and drive (2) XL4 klystrons using an existing 1:10 pulse transformer 400kV 630A 3.2 µsec. (Operational) 5. DFM (Integrated 2-Pack): Design and build a DFM Modulator using 12 turn secondary transformer to drive 2 XP klystrons (Project change to ILC, design never completed) Page 4
SLAC Induction Modulator Development 8/4-Pack Table-top 2-Pack Table-top 37.5µF @4.3 kv capacitors 3.3 kv IGBT 6.5 kv IGBT Larger IGBT heat sink Page 5
NLC 8-PACK (8-XP) MODULATOR Water Load 500 kv, 650 Amps CORES AND SECONDARY 76 Primaries @ 5400 A 3 Turn Secondary 400 kv @ 1800 A, 725 Meg watts for 3.2µs, 350 kw Ave. SOLID STATE DRIVERS 152 IGBT s Drivers (two per Primary) 1800 volts per IGBT 2700 Amps per Driver 5045 Klystron 400 kv, 450 Amps Page 6
NLC 4-PACK (4-XL4) MODULATOR controls Klystron supplies drivers CORES AND SECONDARY 76 Primaries @ 5400 A 3 Turn Secondary 400 kv @ 1200 A, XL4 Klystrons 400kV @ 320 A 1.6 µsec SOLID STATE DRIVERS 76 IGBT s Drivers 1800 volts per IGBT 3600 Amps per Driver (4) XL4 Klystrons 400kV 1200A Page 7
Table-top (6575 Equivalent) Modulator IGBT DRIVER Collector GRN Grid +15V Emitter DRVn1 C10 100ufd 3kv Dn1 8kv T10 Qn1 23 kv Cn2 6000 A 1/1 50ufd 400v 2 ea 3.3Kv 800A + + 20 IGBT drivers 10 CORE sections + + C31 100ufd 3kv 23 kv, 6.0 ka IGBT DRIVER Q31 D31 8kv T31 Collector 0.007 V-Sec GRN C32 3 usec Grid +15V 1/1 Emitter 2 ea 3.3Kv 800A 50ufd 400v DRV31 C21 100ufd 3kv IGBT DRIVER Q21 D21 8kv T21 Collector GRN C22 Grid +15V 1/1 Emitter 2 ea 3.3Kv 800A 50ufd 400v DRV21 C11 100ufd 3kv IGBT DRIVER Q11 D11 8kv T11 Collector GRN C12 Grid +15V 1/1 Emitter 2 ea 3.3Kv 800A 50ufd 400v 5045 KLYSTRON 340 kv 396 A 3 us 1/15 Pulse Transformer 10 Primaries @ 5400 A 20 IGBT drivers 2.2 kv, 2.7 ka 1 Turn Secondary 1:15 conventional X-former 330 kv, 360 A (Note: Rise time slow due to pulse transformer leakage inductance and stray capacitance) Page 8
NLC DFM1 Hybrid Modulator Water Load 500kV 500A 37.5µF @4.3 kv (2) XK4 capacitors Klystrons 400kV 440A DFM1 Hybrid modulator utilizing DFM fabricated parts; Larger IGBT heat sink15 Metglas cores, 30 IGBT drivers, with a single secondary turn driving a conventional 1:10 pulse transformer: 530kV, 600A, 1.6 µsec, 120 Hz Page 9
ORION 5045 Klystron Modulator 2 > 2 > 1 > 1 > 8 cells @ 24kV, 6kA 8 Primaries @ 6210 A 16 IGBT drivers: 3.0 kv, 3.1 ka 1 Turn Secondary 1:15 conventional X-former: 360 kv, 414 A 1) Iout 200A/V: 5 VOL 50037.5µF nsec @4.3 kv 2) Vout 1kV/V: 5 VOL 500 nsec capacitors Resistive load 4 ohms 30nF Modulator only 24kV 6000A Page 10
SLAC Modulator Program Conclusions IGBT-based solid state modulators are capable of meeting (and exceeding) the high power klystron requirements R&D opportunities to improve efficiency, fault tolerance, and modulator lifetime Pulse power optimized IGBT High voltage, high bandwidth adder design Integrated HLRF design: optimize entire source including modulator Page 11