February 23, 2006 1HA Power Supplies - Demonstration Criteria and Status

ATF2 Project HA Power Supplies

Demonstration System Evaluation Criteria

And

Status as of February 23, 2006

Paul Bellomo and Briant Lam

February 23, 2006 2HA Power Supplies - Demonstration Criteria and Status

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

February 23, 2006 3HA Power Supplies - Demonstration Criteria and Status

Rack and Power System Layouts

February 23, 2006 4HA Power Supplies - Demonstration Criteria and Status

System Block Diagram

Note that the demonstration system might not include all the elements shown in this block diagram

February 23, 2006 5HA Power Supplies - Demonstration Criteria and Status

Availability Improvement By Oversizing and Redundancy

February 23, 2006 6HA Power Supplies - Demonstration Criteria and Status

Test Parameters and Success Criteria

Evaluated Parameter Success 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

RedundancyLoss 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 control New Ethernet controller

February 23, 2006 7HA Power Supplies - Demonstration Criteria and Status

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

February 23, 2006 8HA Power Supplies - Demonstration Criteria and Status

The System

February 23, 2006 9HA Power Supplies - Demonstration Criteria and Status

Operating Power Supplies

February 23, 2006 10HA Power Supplies - Demonstration Criteria and Status

The Power Modules

February 23, 2006 11HA Power Supplies - Demonstration Criteria and Status

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

February 23, 2006 12HA Power Supplies - Demonstration Criteria and Status

Environmental Test Chamber

February 23, 2006 13HA Power Supplies - Demonstration Criteria and Status

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