The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory operates the world's largest and most energetic laser. The facility supports studies of high energy density physics with the ultimate goal of achieving ignition and energy gain for the first time in a laboratory setting. The success of its mission depends heavily on key subsystems like the Power Conditioning System (PCS), where near 100% availability is required in supporting 24/7 laser operation. The 192 modules of PCS store and then deliver approximately 400 MJ of electrical energy to the laser amplifiers. The sheer number of modules coupled with the aggressive shot schedule present a challenge for both preventive maintenance and the implementation of engineering changes. Because the system comes into play very late during the shot process, it is extremely important to minimize the number of occurrences and duration of reactive maintenance activities. We will discuss PCS performance, training and maintenance strategies, along with a series of development and upgrades that will help assure long-term system reliability and availability while supporting NIF's missions.
The National Ignition Facility (NIF) is a 192-beam laser fusion driver operating at Lawrence Livermore National Laboratory. NIF relies on three large-scale pulsed power systems to achieve its goals: the Power Conditioning Unit (PCU), which provides flashlamp excitation for the laser's injection system; the Power Conditioning System (PCS), which provides the multi-megajoule pulsed excitation required to drive flashlamps in the laser's optical amplifiers; and the Plasma Electrode Pockels Cell (PEPC), which enables NIF to take advantage of a four-pass main amplifier. Years of production, installation, and commissioning of the three NIF pulsed power systems are now complete. Seven-day-per-week operation of the laser has commenced, with the three pulsed power systems providing routine support of laser operations. We present the details of the status and operational experience associated with the three systems along with a projection of the future for NIF pulsed power.
Summary form given only. The Power Conditioning System of the National Ignition Facility provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) stores up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 mus pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning System continue to progress rapidly, with the goals of completing accelerated production in late 2007 and finishing commissioning by early 2008, all the while maintaining an aggressive operations schedule. To date, more than 60% of the required modules have been assembled, shipped and installed in the facility, representing more that 240 MJ of stored energy available for driving NIF flashlamps. The MESMs have displayed outstanding reliability during daily, multiple-shift operations.
The National Ignition Facility (NIF) Power Conditioning System (PCS) is a modular capacitive energy storage system that will be capable of storing nearly 400 MJ of electrical energy and delivering that energy to the nearly 8000 flashlamps in the NIF laser. The first sixteen modules of the power conditioning system have been built, tested and installed. Activation of the first nine power conditioning modules has been completed and commissioning of the first "bundle" of laser beamlines has begun. This paper will provide an overview of the power conditioning system design and describe the status and results of initial testing and activation of the first "bundle" of power conditioning modules.
The National Ignition Facility (NIF) Power Conditioning System (PCS) is a modular capacitive energy storage system that provides over 34 kilojoules of energy to each of the nearly 8000 flashlamps in the NIF laser. Up to 400 megajoules of energy can be stored in the NIF PCS system, discharged through spark gaps and delivered to the flashlamps through a coaxial transmission line system requiring nearly 100 miles of high-voltage cable. The NIF PCS has been under development for nearly 4 years. During this time, the system was developed and designed by Sandia National Laboratory in Albuquerque, NM (SNLA) in conjunction with Lawrence Livermore National Laboratory (LLNL). Extensive reliability testing was performed at SNLA on the First Article NIF Test Module (FANTM) test facility and design improvements were implemented based on FANTM test results, leading to the final design presently undergoing system reliability testing at LLNL. Low-cost energy-storage capacitors, charging power supplies, and reliable, fault-tolerant components were developed through partnerships with numerous contractors. Extensive reliability and fault testing of components has also been performed. This paper provides an overview of the many efforts that have culminated in the final design of the NIF PCS. The PCS system design will be described and the cost tradeoffs discussed. Plans for fabrication and installation of the NIF PCS system over the next 6 years will be presented.