Paul Bellomo and Briant Lam

1
ATF2 DC Magnet Power Supplies Paul Bellomo and
Briant Lam
2
Scope and Summary

• Phase 1 Demonstration Phase
• To demonstrate performance, control and
  redundancy. One (1) system with four modules,
  each rated 20V, 50A in a three out of four
  configuration, for a rated output of 20V 150A.
• Major components. Ethernet controller, bulk power
  supply, power supply modules and crate, current
  transductor, and interconnecting cables. These
  components might not be exactly the same as the
  Phase 2 components.
• 29k cost. March 31, 2006 completion
• Phase 2 System Design Phase
• Forty-one (41) systems for accelerator use
• Major components. Ethernet controllers, bulk
  power supplies, power supply modules and crate,
  current transductor, and interconnecting cables
• 671k cost. Start April 1, 2006 and October 31,
  2007 delivery
• Phase 3 Installation, Training and
  Commissioning Phase
• Spares, installation, training, and maintenance
  issues. Spares cost 38.3k. Installation Training
  and Commissioning Cost 293k

3
Glossary of Terms
4
Phase 1 Preliminary Power Supply List (For
Phase 2)
5
Phase 1 Design Basis

• Forty-one (41) DC power supplies
• All are 20V output, current outputs are multiples
  of 50A
• A 20V, 50A modular approach will minimize number
  of power supply types, spare parts inventory and
  maintenance
• A modular approach further suggests redundancy
  for high availability (HA)
• Buck regulator modules are high efficiency,
  switch-mode. Switching frequency is than 20 kHz
  for audible quietness and small size

6
Phase 1 - Typical System Block Diagram
7
Phase 1 Availability Improvement by Parts
Reduction and Module Redundancy
8
Phase 1 - Bulk Power Supply Types
Purpose voltage source that provides raw power
for modules

• Simple Rectifier Bulk Supply
• 6 or 12 pulse
• Transformer matches line V to load V. Operates _at_
  50Hz LARGE and heavy
• Control and interface issue
• Difficult to rack-mount
• Not recommended

• Switch-mode Bulk Power Supply
• Line to load V matching transformer is downstream
  of high frequency gt 20kHz switching element.
  Small size and light
• Each 30V, 400A 12kW
• Recommended

9
Phase 1 - Bulk Power Supply Manufacturers
Elgar Electronics Corporation9250 Brown Deer
RoadSan Diego, CA 92121 Website
www.elgar.com IE Power 12 Falconer Drive, Unit
15Mississauga, OntarioCanada L5N
3L9www.iepower.com Lambda-EMIAroma Square Bldg
5F Kamata, Ohta - KuTokyo 144-8721
Japanwww.densei-lambda.com Matsusada - Shiga
Headquarters 745 Aoji-Cho,Kusatsu -City, Shiga,
525-0041 Japan www.matsusada.com
10
Phase 1 Power Module Buck Regulator Topology
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Phase 1 Power Module Current Sharing Options

• Master-slave. Failure of master takes down entire
  set of modules. Defeats the redundancy intent.
  Not recommended
• Droop. Do nothing. Connect the power supply
  outputs in parallel. Relies on degrading output
  impedance of the power supplies to equalize the
  power supply or module output currents. Stability
  acceptable but regulation (immunity to
  transients) suffers. No control over current
  sharing precision. Not recommended
• Democratic. Recommended approach and discussed
  further in subsequent slides

12
Phase 1 Democratic Current Share Circuitry
13
Phase 1 The Power Modules

• Purpose current regulation of magnet current
• All 20V, 50A
• Parallel for current share and redundancy
• OCEM Italy IE Power Canada

14
Phase 1 - Ethernet Power Supply Controller

• Purpose
• Interfaces remote computer to power supply
• Closed loop control for current setting and
  regulation
• Features
• EPICS IOC (if desired by KEK, but not yet
  integrated into the demonstration controller)
• 100Mbps TCP/IP communications via the UDP
  protocol
• Built on excellent performance of controllers
  employed in PEP and SPEAR, 300,000hrs MTBF.
  Controllers slated for LCLS project use.

15
Phase 1 - Current Transductor
Purpose Monitors output current for use in
regulation loop Monitors current for system
display and histograms
GMW Associates955 Industrial RoadSan Carlos, CA
94070650-802-8292 ian_at_gmw.com Hakuto Company
Ltd. Scientific Equipment Department, 1-13,
1-chome, Shinjuku, Shinjuku-ku, Tokyo 160,
Japan Tel. [phone]
0.3 ppm / OC
16
Phase 1 - Cost Estimate
Materials Three power modules, add current
share 2,500 Bulk power supply 4,000 Power
supply controller 2,000 Miscellaneous
hardware 1,000 Materials total 9,500
Labor 1 Engineer for 5 months _at_ 15 time_at_
19k/month 14,000 1 Technician for 5 months _at_
10 time _at_ 11k/month 5,500 Labor
total 19,500 Total cost 29,000
17
Phase 1 - Schedule and Status
18
Phase 2 - Configuration of 41 Systems
Assumes racks are available and suitable for use
as depicted Brown modules, Blue spares
19
Phase 2 - Cost Estimate
20
Phase 2 - Schedule
21
Phase 3 Recommended Spare Parts
22
Phase 3 Installation and Training

• KEK provides site
• AC panel-board locations for power supply input
  power
• DC cable tray layouts
• Locations of the remote computer connections and
  termination points
• Details of the magnet and personnel protection
  systems
• Rack details
• System software
• SLAC provides
• Wiring diagram for each of the 41 systems. These
  diagrams show the intra-rack cables.
• Installation drawings of the AC power conduits
  and cables.
• Installation drawings showing the routing of DC
  cables from the power supplies to the magnet
  loads via the KEK Cable tray system
• Controller software

23
Phase 3 - Schedule

24
Phase 3 - Costs
25
Cost Summary and Closing Slide
26
Discussion Issues and Closing Slide
SLAC provides assembled racks with AC
distribution to reduce installation and travel
costs.