HA Power Supplies - Demonstration Criteria and Status February 23, ATF2 Project HA Power Supplies Demonstration System Evaluation Criteria And Status as of February 23, 2006 Paul Bellomo and Briant Lam

HA Power Supplies - Demonstration Criteria and Status February 23, Demonstration Criteria Build a power system with Ethernet control that will provide 150A in a 3 out 4 redundant module configuration. Demonstrate performance, redundancy and current sharing

HA Power Supplies - Demonstration Criteria and Status February 23, Rack and Power System Layouts

HA Power Supplies - Demonstration Criteria and Status February 23, System Block Diagram Note that the demonstration system might not include all the elements shown in this block diagram

HA Power Supplies - Demonstration Criteria and Status February 23, Availability Improvement By Oversizing and Redundancy

HA Power Supplies - Demonstration Criteria and Status February 23, Test Parameters and Success Criteria Evaluated ParameterSuccess Criteria Rated load current from redundant configuration 150A regulated output from either 4 modules or 3 modules Load current sharing ≤ 5% current mismatch from 3 or 4 modules at 100% and 25% rated output Redundancy Loss of one module, system recovers current within 1 millisecond Current stability versus time and temperature ≤ 3 ppm drift in 10 minutes, monitor  ≤ 10 ppm drift in 8 hours, monitor  Bandwidth≥ 10Hz by Bode plot Ethernet controlNew Ethernet controller

HA Power Supplies - Demonstration Criteria and Status February 23, Status as February 23, 2006 Presently operating and evaluating five parallel-connected power modules under closed loop control under BitBus control Operating with phase-shifted input PWM signals to increase effective switching frequency and reduce output ripple. Operating to a combined 100A of load current while monitoring individual power module output current and output ripple voltage. Observed nicely balanced currents in the power modules. Correlated load current sharing to the precision of match among the five phase- shifted PWM signals. Simulated a failure of one power module by disabling the PWM signal to one power module during five power module operation to 100A,. Observed a re- distribution of load current among the remaining four operating power modules. This indicates that the redundancy scheme is feasible. Confirmed the expected increase in output voltage ripple when one power module is disabled. The demonstration system is on a correct technical path, it is on budget and it is on schedule

HA Power Supplies - Demonstration Criteria and Status February 23, The System

HA Power Supplies - Demonstration Criteria and Status February 23, Operating Power Supplies

HA Power Supplies - Demonstration Criteria and Status February 23, The Power Modules

HA Power Supplies - Demonstration Criteria and Status February 23, Near-Term Next Steps 1.Operate four power modules in a three-out-of-four redundant configuration connected to an inductive load to provide a combined output of 150A. Upon the loss of one module the remaining three will each operate at their rated output of 50A. Monitor the transient current re- distribution among the power modules under these conditions. 2.Place four power modules into an environmentally-controlled temperature chamber (refer to the next slide). Connect them to an inductive load. Test the load current stability and power module current sharing versus time and temperature of the three-out-of-four configuration. 3.Upgrade the BitBus controller to an Ethernet controller

HA Power Supplies - Demonstration Criteria and Status February 23, Environmental Test Chamber

HA Power Supplies - Demonstration Criteria and Status February 23, End Slide - Development Workaround During Decision Period Workaround during decision phase Item 3 critical path – Interface with KEK to specify the controls, performance/features of the power modules and their crates