1. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Low Voltage System for the Alice TPC " Test of Wiener PL500 supply " Alternative scenario: DC-DC converters

2. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Test of Wiener PL500 Supply Test setup: Resistor network on loan from CAEN CANbus software by GSI summer student

3. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Test of Wiener PL500 Supply Testresult noise:

4. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Test of Wiener PL500 Supply Testresult load variation:

5. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Test of Wiener PL500 Supply Preliminary conclusions: behaves as expected: regulation and „differential“ noise „common mode“ noise needs further study Next steps: connect to test setup with CERES preamps ship to CERN for further tests General: due to reduction of power consumption according to the latest estimates: price for LV system will be considerably reduced

6. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Konfiguration existing at GSI now: Test of Wiener PL500 Supply CAN bus interface common services 4 modules with up to 7 V and 115 A each, always 2 in parallel

7. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI DC-DC Converters First test results by CAEN are available: -> slides by 7th Conf. on Advanced Technology and Particle Physics Como, 15-19 Oct 2001 Giuseppe Vitale

8. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Results (III) = B field // to toroid plane = High power (I load: up to 36 A) = B up to 10 kG = Efficiency loss due to B : 11% DC-DC Converters

9. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI DC-DC Converters DC-DC Converter control philosophy

10. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI " A 4V 36A DC-DC Converter has been developed for LHC applications " First prototype successfully passed all radiation and magnetic field tolerance tests

11. Rainer Renfordt IKF Frankfurt TPC meeting 10/11December 2001 @ GSI Possible scenario based on presently available information: modules for 4 V and 36 A with a size of 10 x 10 x 10 cm3 one would need (2 + 4)/Sektor*36 = 216 converters -> conceivable mounting on endplate, cooling needs study open questions: electromagnetic noise? price? packaging? More tests are planned for next year (G. Stefanini) -> for the moment the Wiener supplies are still the baseline solution DC-DC Converters