Current Step Generation and Measurement with Nanosecond Rise Time using Coaxial Cable Generator

Current step generator is designed and tested based on charged coaxial cable for characterization of impulse current shunts. Current coil sensors were used with the shunts in measurement circuits for calibration of shunts. Solution is presented for current step generation to achieve the rise time of as low as 5 ns. Various sensors were used to measure generated current steps with steep front. Generation system consists of 110 m-long, 50 Ω coaxial cable and SF
₆
spark gap. Current steps with stable current up to 100 A were generated. Depending on the spark gap used for switching, and on the geometry of the setup, the measured rise time varied from 1.6 ns to 15 ns.