Availability assessment of water-cooled DC power supplies for 70 kW and 40 kW, 650 MHz solid state RF amplifiers

Abstract The assessment of availability is a critical requirement of any accelerator facility and it allows incorporation of appropriate mitigation strategies to minimize unscheduled interruptions during the operation. Several units of 70 kW and 40 kW, 650 MHz solid state RF amplifiers (SSA) will be required in 800 MeV proton LINAC for powering its high-beta and low-beta superconducting RF cavities respectively. The 70 kW and 40 kW SSAs will be biased by 50 V, 3300 A water-cooled DC power supply and 50 V, 1950 A water-cooled DC power supply respectively. In 50 V, 3300 A DC power supply, total 28 (22 + 6 active redundant) numbers of 50 V, 150 A DC power supply modules (PS modules) are connected in parallel to create a 50 V, 3300 A DC bus. Similarly in 50 V, 1950 A DC power supply, total 16 (13 + 3 active redundant) numbers of 50 V, 150 A DC PS modules are connected in parallel to create a 50 V, 1950 A DC bus. The availability requirement of DC power supplies of 70 kW and 40 kW SSAs is > 0.99998 as demanded by proton LINAC. Various steps are taken to improve the reliability of individual PS modules and DC power supplies. Availability assessment of water-cooled DC power supplies of 70 kW and 40 kW SSAs has been carried out and presented in this manuscript. The availability of water-cooled DC power supplies for 70 kW and 40 kW SSA systems are estimated to be > 0.99998.