1. FERMILAB LINAC PROTON SOURCE MODULATORS Dan Wolff/Howie Pfeffer

2. MODULATOR SPECS • Output Voltage: 120kV • Output Current: 140 amps • Output Pulse Length: 4.5 ms • Pulse Rate: 3 Hz • Input Voltage: 480 VAC • Spark Energy Limit: 20 joules • Regulation (incl. slope): 1 % (?) • Design should minimize cost for upgrade to 10 Hz pulse rate at 1.5 ms pulse width. Dan Wolff/Howie Pfeffer

3. POTENTIAL MODULATOR TECHNOLOGIES • FNAL (Bouncer-type) with Updated Technology * Higher Voltage IGBTs, New Caps, New Controls • SNS – High Frequency Switcher + Small Size + Being commercially produced - As yet, unproven operational reliability - Passive circuit on secondary to control spark energy deserves further investigation - HV/HF Transformer is tricky. Is it reliable? - Pulse flattening yet to be demonstrated • Miss-Matched PFN – Russian Idea, not demonstrated + No Bouncer Needed + Interesting, might be more reliable - Need to build one Dan Wolff/Howie Pfeffer

4. FNAL Bouncer-type 4.5 ms Modulator “Simplified” Schematic Dan Wolff/Howie Pfeffer

5. Bouncer-type Modulator with Updated Technology • IGBT Switch: • Using New Higher Voltage Devices: 50% reduction in cost and physical size • Main Capacitor Bank: Using New “HAZY” Self-Healing Polypropylene Capacitors 50% Reduction in Cap Cost and Physical Size • Modulator Controls: Using Lab G type – SM Components, fewer cable interconnects 25% reduction in parts, 50% reduction in labor Dan Wolff/Howie Pfeffer

6. Bouncer-type Modulator - New Features • Redundant IGBT Switch Design - Eliminating the Backup Switch: 20% reduction in cost - BUT Requires redundancy in number of switch devices and gate controls - Replaces Ignitrons with less expensive SCRs in crowbar circuit - Eliminates very high current crowbars and associated noise - Maybe a zero gains feature but better reliability • Boost Converter Regulation - Goal is to achieve +/- 5% control/regulation - Allows for multiple modulators fed from one charging power supply. • Smoothing Choke - Series choke of sufficient size to limit AC line fluctuations to +/- 1% (present Linac area AC lines 15Hz voltage distortion). - If new Linac fed from dedicated 345kV transformer, above requirement could be relaxed. Dan Wolff/Howie Pfeffer

7. 4.5 ms Modulator Design Features thatminimize 1.5ms upgrade costs • 2 parallel IGBT Switches • Main Cap Bank designed to separated into 3. RMS current based on 10 Hz 1.5 ms operation • Bouncer Caps and Inductors designed to be separated into 3. RMS current based on 10 Hz 1.5 ms operation • Charging Power Supply Assuming boost converter regulation works, the same charging PS could be used to power 3 of the 1.5 ms modulators. Dan Wolff/Howie Pfeffer

8. Original FERMI TESLA MODULATOR – Parts Cost • Pulser Parts Cost • Pulse Transformer: $108k • Pwr Transformer: $ 50k • Main Cap Bank: $ 31k • Cabinet: $ 15k • Other: $126k • Subtotal: $330k • IGBT Switch Subtotal: $ 50k • Modulator Controls Subtotal: $ 40k • TOTAL: $420K Dan Wolff/Howie Pfeffer

9. Original FERMI TESLA MODULATOR – Total Cost PULSER PARTS ESTIMATE: $420k RF MODULES (Spark Detection): $12k (AWAG) • LABOR ESTIMATE: (Total parts cost) – (Pulse Transformer) $422k - $108k = $314k • TOTAL (1996 $’s): $735k • TOTAL: Inflation Since 1996 (8 yrs at 2.5%/yr) = 22% 1.22 x $735k = $900k Dan Wolff/Howie Pfeffer

10. Original Fermi TESLA Modulator Updated Technology cost savings • IGBT Switch: Using New Higher Voltage Devices and eliminating the backup switch: • $60k savings in labor and parts • Main Capacitor Bank: Using New “HAZY” Self-Healing Polypropylene Capacitors • $30k savings in labor and parts • $5k savings in Cabinet, Reduced Service Building Size! • Controls Upgrade: • $30k Savings in parts and labor Total updated technology savings: $125k • TOTAL: Inflation Since 1996 (8 yrs at 2.5%/yr) = 22% 1.22 x ($735k-$125k) = $745k Dan Wolff/Howie Pfeffer

11. 4.5 ms Modulator Cost Estimate • Pulse Transformer: $108k [ x sqrt(3) ] $190k • Pwr Transformer: $ 50k [same] $50k • Main Cap Bank: $ 31k [ x1/2 x3] $50k • Cabinet: $ 15k [ x8/5 ] $25k • Other: $126k [see notes] $270k Subtotal: $585k • IGBT Switch Subtotal: $ 50k [ x 4/10 x2] $40k • Modulator Controls Subtotal: $ 40k [x 5/8] $25k • TOTAL parts: $650K Dan Wolff/Howie Pfeffer

12. 4.5 ms Modulator Cost Estimate – Total Cost PULSER PARTS ESTIMATE: $650k RF MODULES (Spark Detection): $12k (AWAG) • LABOR ESTIMATE: (Total parts cost) – (Pulse Transformer) $650k - $190k = $460k • TOTAL parts and labor (1996 $’s): $1122k • TOTAL: Inflation Since 1996 (8 yrs at 2.5%/yr) = 22% 1.22 x $1122k = $1370k Dan Wolff/Howie Pfeffer

13. ESTIMATED SIZE !Simple scaling, no attempt to optimize Dan Wolff/Howie Pfeffer

14. 4.5 ms ModulatorProject Organization • Project Leader: Howie Pfeffer • Magnetics: Chris Jensen • Controls: Jim Biggs (& P. Prieto) • Switch, Cap Bank, Bouncer, Misc., Leon Bartelson and construction: • Computer Simulations: Dan Wolff • Estimated project time Design, construction, and commissioning: 18 months after $’s available. Dan Wolff/Howie Pfeffer