Capacitor Bank Module for Multi Megajoule Energy Storage

Abstract

Summary form only given. Within the context of the pulsed power system's development undertaken by CEA for the megajoule laser (LMJ) facility, new capacitor bank module (CBM) is developed by ILICE (Tomsk) and ITHPP (France). Two CBMs were produced and tested in Tomsk. Large number of modules (480) in the complete LMJ installation imposes strict requirements to CBM's parameters. These include reliability of the elements (30 years estimated LMJ lifetime), cost minimization, ability' to withstand failure regime, stability from shot to shot in controlled parameters, limits on size and weight, easy maintenance, and a row of other technical requirements. Main parts of the CBM are: HV power supply, control system, air conditioning system, capacitor block, cables delivering the energy to the load. The capacitor block includes 1 preionization and 10 main capacitors, 1 preionization and 1 main switches, charging and damping resistors, pulse shaping inductors, high voltage relays and safety system. Control system provides operation of the capacitor block in selected mode, monitoring and recording currents as well as voltages, command for dumping at failure and some other functions. CBM's parameters are: total capacitance 3000 muF, charge voltage up to 24 kV, peak current amplitude 240 kA, peak stored energy 864 kJ, pulse width at 10% of peak power 360 mus, dimensions 2.3times1.5times2.5 m3, weight ~2500 kg. In nominal regime (24 kV, 40 m cables), the energy delivered to the flash lamps in each channel is 74 kJ (86% efficiency). No failures were observed in more than 1000 test shots and all the CBM parameters are well within the requirements. Detailed description of the CBM and test results is given in the report.