FANTM: First Article NIF Test Module

Designing and developing the 1.7- to 2.1-MJ power conditioning system (PCS) that power the flashlamps of the main and power amplifiers for the National Ignition Facility (NIF) lasers is one of several responsibilities assumed by Sandia National Laboratories (SNL) and Maxwell Physics International in support of the NIF Project. The NIF is currently being constructed at Lawrence Livermore National Laboratories (LLNL). The test facility that evolved over three years to satisfy the project requirements is called the First Article NIF Test Module (FANTM). It was built at SNL and operated for about 17000 shots to demonstrate component performance expectations over the lifetime of NIF. A few modules are used initially in the amplifier test phase of the project. The final NIF system requires at least 192 modules in the four capacitor bays. The paper briefly summarizes the final design of the FANTM facility and compares its performance with the predictions of circuit simulations for both normal operation and fault-mode response. Applying both the measured and modeled power pulse waveforms as input to a LLNL amplifier gain code indicates that the 20-capacitor PCS can satisfy the NIF requirement for an average gain coefficient of 5.00%/cm and can exceed 5.20%/cm with 24 capacitors.