Study of the virtual instrumentation applied to measure pulsed heavy currents

The design and implementation of a high-performance virtual instrumentation (VI) based on the Rogowski coil are discussed. The instrumentation can measure pulsed heavy currents of the high-power high-voltage laser source whose performance indices are introduced. The analysis of models, including both time-domain and frequency-domain characteristics of the Rogowski coil, is presented. Problems related to the data acquisition systems (DASs), including the window data transfer technique, have been investigated to meet the requirements of real-time testing applications. Some experimental results verifying the validity of the proposed instrumentation for measuring pulsed currents of the laser source are presented.

I. Introduction

The PRINCIPLE of measuring the current with a Rogowski coil has been known since 1912 [1]. Recently, attention has been paid to the use of the Rogowski coil transducer for measuring currents in the region of a few tens of kiloamps, which have significant high-frequency components. The coil has a wide bandwidth that only depends on its type. What is more, it has no core saturation effects, a compact structure, and is lightweight. The coil is linear: the same coil transducer can be used to measure current in a wide range. It is also accurate: the system can be made with an uncertainty better than 0.1%, see [2]–[3] [4].