A Novel Self-Powered Lightning Current Measurement System

Abstract

To address the lack of reliable power supplies for lightning current measurement systems (LCMS), this paper proposes a novel self-powered LCMS. The required operation power of a LCMS can be provided by harvesting the surge current that is measured using a power coil such that the system can be energized to complete a single-cycle measurement and data recording. In this manner, the stand-alone LCMS is triggered by lightning currents, and, hence, the signal acquisition can be activated automatically. In particular, this paper designs a two-channel passive peak-holding circuit as a low-power substitution to the conventional high-speed sampling modules. The polarity, current peak, and trigger time can be measured and ultimately be stored in a nonvolatile memory. The theoretical and simulation studies are presented in detail to determine the structure, size, and number of winding turns of the power and signal coils. The circuitry design of the power supply and signal conditioning units are also addressed. Experimental results verify that the proposed LCMS can accurately measure the amplitudes of lightning currents, achieving an accuracy of a maximum error of 4%, while the LCMS is fully self-powered to satisfy the energy demand from the measurement and data acquisition tasks.