NUMI NuMI Magnet Power Supply System WBS Power Supply System Level 3 Manager Nancy Grossman FNAL July 11, 2001

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 2 Outline Overview and Specifications (Nancy Grossman, 20’)  Conventional Power Supplies and Cables (PS)  Kicker Power Supply and Cables (PS) Status of Refurbished PS (Steve Hays, 30’) Status of Kicker PS (Chris Jensen, 30’) Status of Cooling System for PS (Dave Pushka, 30’) Cost/Schedule/Concerns (Nancy Grossman, 10’)

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 3 Overview of the Magnet Power Supply System Conventional Power Supplies (PS) (all existing PS’s to be refurbished or bought from FNAL spares inventory; Steve Hays, Bob Ducar)  Ten 500 KW PS  1 Main Ring PS  Three 240 KW PS (one used at MI8 for testing horns)  Ten 20 KW PS  PS for 12 Main Injector trim magnets 1 Kicker PS (to be designed, built and tested; Chris Jensen) AC (480 panel to PS) and DC Power Supply Cables and Connectors (Steve Hays, Bob Ducar) All large power supplies are ramped. All quad and trim PS’s are DC and have their own PS.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 4 Refurbished Magnet Power Supplies Specifications Conventional Power Supplies and Cables (Steve Hays, Bob Ducar) Must provide reliable, stable power to beamline elements while minimizing power consumption. The NuMI facility is expected to be operational for of order ten years, and the power supply system has been designed with this in mind. Power supplies must accommodate a repetition period of 1.9 seconds (~1 msec flatop).  Want PS to stabilize at flatop, read it to check current and have time to still extract. Personnel safety must be assured from possible electrical, mechanical and radiological hazards during installation and operations. Voltage and current requirements for the various beamline elements determine what power supplies and cables will be needed.  Table summarizes these requirements and indicates the chosen power supply for each case. For beam tuning and focusing, each trim and quadropole magnet has its own power supply. Bend circuits use several 500 kW supplies in series (or for the V105 circuit a Main Ring Power Supply) in order to obtain the desired voltage levels.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 5 Refurbished Magnet Power Supplies: MI60

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 6 Technical Progress & Status: HV101 PS at MI60

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 7 Technical Progress & Status: V100, LAM60 and Quad PS MI60

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 8 Refurbished Magnet Power Supplies: MI62

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 9 Refurbished Magnet Power Supplies: Target Hall Service Building

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 10 Refurbished Magnet Power Supply Regulation Power supply regulation “requirements” shown below  Groundwater irradiation  Stability of beam on target 720 Hz line ripple effect on the PS currents is shown in the table below.  Need filters on all bend strings

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 11 Refurbished Magnet Power Supply Regulation Simulations were run for the NuMI V105 string, assuming a constant reference voltage. 5% change in line voltage was easily corrected for at the level of ~25 ppm with standard voltage regulation. (most variation one would expect) 5% load change (resistance) gave a 240 ppm current variation.  Corresponds to about a 10 0 C change in the copper in the magnet or the LCW changing 15 0 C  Need additional regulation.  HOLEC transductor ($5K/string) & Special FNAL regulation electronics ($5K/string)  Both are designed and installed in the Main Injector  This combination of electronics would give another factor of ppm

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 12 Refurbished Magnet Power Supply Regulation Three strings are still above the required specifications. So now what?

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 13 Refurbished Magnet Power Supply Regulation Bandwidth Each string will be tuned for maximum bandwidth.  20 Hz is assumed in the previous calculations, 40 Hz may achieved (but not guaranteed).  Gives a factor of 2 in current stability. Auto-tune Load changes are typically slow changes and thus Auto-tune can correct for these. One could then argue why do you need the extra power supply regulation too?  Auto-tune does not always work.  Needs beam and working beam position monitors to work.  Assumes next beam pulse like the previous one.  Experience at FNAL where significant beam control is needed says do both.  Since the power supply regulation is also driven some by groundwater concerns, we want something that is always working.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 14 Refurbished Magnet Power Supply Regulation NuMI bend string power supply regulation levels will be achieved by:  Filters on all 7 strings.  HOLEC and FNAL Electronics on all 7 strings.  Auto-tune.  Tuning for maximum bandwidth. Quadropole power supplies (20 KW PEI’s):  Standard regulation is at +/- 0.05% of the maximum current (100 or 200 amps)  Corresponds to up to +/-0.44% variation in operating current.  Believed to be sufficient. Main Injector Trim Magnet power supplies:  Standard regulation is at +/- 0.1% of the maximum current (15 amps)  Believed to be sufficient.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 15 Refurbished Magnet Power Supplies Status Conventional Power Supplies and Cables (Steve Hays, Bob Ducar) MI60 Power Supply Cables:  DC cable pulls complete (except kicker PS), including termination on PS side.  AC cabling of power supplies is complete (except kicker PS). MI62 Power Supply Cables:  AC cabling done except for Main Ring PS. Conventional Power Supplies:  9 refurbished, 4 for Target Hall still need to be refurbished.  Ones in existing construction are also in place (except MR PS and Kicker PS).  6 large power supplies, 7 quads and 12 trim power supplies.  Testing of the PS will begin shortly.  Filter chokes and the Main Ring PS need to be installed (not behind schedule).  Scheduled to happen soon. All ahead of schedule and within budget.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 16 Specifications for the Extraction Kicker Minimum Integrated Field: 2.24 kG - m Kick 120 GeV: 563 µrad to inside of ring Field Rise Time (1%-99%): 1.30 µs Field Fall Time: N/A Field Flattop Time: 9.78 µs minimum( 6 batches) Flattop During Pulse:± 1% Flattop pulse to pulse:± 1% Repetition Rate:1.9 seconds Required Charging Time:1.5 seconds Magnet Location: Immediately Downstream Q602 Power Supply Location: MI-60 Service Building, South Power Supply Room

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 17 Kicker Power Supply Kicker Power Supply - based on MI-52 kicker design (Chris Jensen) Design modifications to change polarity of supply. (Significant design effort.) Pulse Forming Network driving two (or three series/parallel) magnets in parallel. PFN has 32 sections, 33 nF/section, 825 nH/section, 46 kV at minimum kick Increase coupling of Pulse Forming Network (versus MI-52) Longer lifetime capacitors for PFN (versus MI-52)

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 18 Kicker Power Supply Work on the charging power supply specification is in progress. Drafting is in progress:  Design is ~40% complete  Swtich tube enclosure 50% complete. Some long lead time parts ordered:  End of line clipper diodes  Controls parts Kicker controls are 30% complete. Much of the design is delayed due to magnet design questions (ceramic tube) Much of the kicker construction, machining and purchase orders will be delayed to FY2003.  Due to funding profile with re-baseline  Still allows several months of float in the kicker construction, testing and installation.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 19 Other Presentations Overview and Specifications (Nancy Grossman, 20’)  Conventional Power Supplies and Cables (PS)  Kicker Power Supply and Cables (PS) Status of Refurbished PS (Steve Hays, 30’) Status of Kicker PS (Chris Jensen, 30’) Status of Cooling System for PS (Dave Pushka, 30’) Cost/Schedule/Concerns (Nancy Grossman, 10’)

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 20 Costs Refurbished Power Supply & Cable Costs  Total Budget: ~$900K  Percent Complete:~48%  Cables, MR PS, regulation/filters, testing Kicker Power Supply and Cables  Based on 2 magnet design….  Total Budget: ~$534K  Percent Complete: ~40%  Need new cost estimate based on 3 magnet design - in progress.

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 21 Schedule & Milestones

NUMI NuMI Internal Review July 11, 2001 Magnet Power Supply System Page 22 Concerns/Summary Refurbishing of conventional PS and installation of their AC and DC cables is ahead of schedule and within budget.  Regulation requirements are tight, but doable  Concerned about integration of the power supply regulation/readout into the NuMI Beam Permit System Kicker Magnet Power Supply  On schedule and budget so far, but…  Will the magnet design change to 3 magnets versus two due to having to use a shorter ceramic tube?  Cost/schedule implications of that are in progress and nearly complete.