Development of Precision Impulse Current Measuring Device

This paper introduces the development and characteristic parameters of a high precision impulse current measuring system. The coil is composed of a multi-layer PCB board, including shielding layer, coil layer, through-hole layer and loop layer. The differential signal output is designed to enhance the anti-interference ability. The requirements of different types of integral circuits for coil parameters are studied, and the relationship between the size, turns and high frequency characteristics of Rogowski coil is studied to ensure that the coil has good high frequency characteristics. The step response test of the measuring device shows that the response time is less than 60 ns and the relative overshoot is less than 10%. Compared with the standard Pearson coil, the peak error is less than 0.2%, the time parameter measurement error is less than 0.3%. The linearity of the measuring device is about 0.3% with current range from 5kA to 40kA. The test results show that the impulse current measuring system can measure high frequency current signal.