Cable for High Pulse Power Applications

Recent development and application of a novel electromagnetic technique, to reposition the coolant tube spacers (garter springs) in the fuel channels of CANDU nuclear reactors, has created the need for a pulse power cable that has very low ac resistance at a frequency range of 700 to 1500 Hz. The technique involved discharging a 200 kJ capacitor bank into an electromagnetic coil, inserted inside the fuel channel, via a transmission line at least 11 m long. The electrical resistance of the transmission line, made of commercially available cables, was found to cause excessive damping of the discharge current waveform which was required to have an exponentially decaying sinusoidal shape. This paper describes the design, development and performance of a new compact cable that has been successfully used to carry repetitive current impulses generated by capacitor banks operating in the oscillatory mode at high current levels. Various dimensional and operational constraints, assembly of the cable terminations by an electromagnetic method and mechanical behaviour of the cable are also discussed.