SHORT-PULSE ROGOWSKI LOOP WITH METAL CORE

The mechanical strength of a Rogowski loop (RL) with a small cross-section and the stability of its electrical characteristics are increased by winding the RL coil on a metal core, which forms with the coil a line with distributed parameters. The load resistor of the RL is placed in an opening of the core, with one lead connected to the core and the other lead connected to the end of the coil; the resistor and its connections to the coil and to the cable that carries the signal have minimal stray inductances. RLs are described that have diameters of up to 1700 mm and nanosecond transient recovery times that are used in the self-integrating mode for the measurement of currents of up to 600 kA with durations of 20-60 nsec. The core reduces the signal amplitude by approximately 10%.