A flexible control scheme for current wave forming using multiple capacitor bank units

Summary form only given. The key issues in high power, high energy applications such as electromagnetic launchers include safety, reliability, flexibility, efficiency, compactness, and cost. To explore some of the issues, a control scheme for a large current wave forming was designed, built and experimentally verified using a 2.4 MJ capacitor bank. The capacitor bank was made up of eight capacitor bank unit, each containing six capacitors connected in parallel. Therefore there were 48 capacitors in total, with ratings of 22 kV and 50 kJ each. Each unit is charged through a charging switch that is operated by air pressure. For discharging each unit has a triggered vacuum switch (TVS) with ratings of 200 kA and 25 kV. Hence, flexibility of wave forming can be obtained by controlling the charging voltage and the discharging timings. The whole control system includes a personal computer, RS232 and RS485 converters, electrical/optical signal converters and eight 80196 micro controller based capacitor-bank unit controllers. Hence, the PC based controller can set the capacitor charging voltages and the TVS triggering timings of each capacitor-bank unit controller for the current wave forming. It also monitors and records the system status data. The RS232 and 485 converters minimize the use optical cables without reducing EMI noise immunity and reliability, this resulting in cost reduction. The paper contains the complete control scheme and details of each subsystem unit. Some experimental current wave forming results are also included.