A development of a shunt lightning current measuring system using a Rogowski coil

Abstract

In recent years, the number of lightning damages has been increased with that of lightning flashes. Therefore, it has become important to understand the features of lightning current damaging electrical and electronics equipment. At the sites of wind turbines and tall antenna towers such as TOKYO SKYTREE ® , lightning current waveforms are observed using large-scale Rogowski coils. Data of not only the main current measured by the large-scale Rogowski coils but also the shunt current damaging electrical and electronics equipment are useful to establish lightning protection methodologies. In this paper, we present the developed system using a Rogowski coil to measure such shunt current.

A Cost-Effective Lightning Current Measuring Instrument with Wide Current Range Detection Using Dual Signal Conditioning Circuits

“…In general, lightning current is detected using a current transformer. To measure a high surge current, a Rogowski coil that does not saturate even at a high current or an expensive and large current transformer with good frequency characteristics is used [ 20 , 21 ]. The proposed LCMI uses an air core Rogowski coil at a price of several hundred dollars, which is relatively economical.…”

“…The output of the circular Rogowski coil follows Ampere’s circuit law, and the voltage ( ) induced in the Rogowski coil can be expressed as [ 20 ] where is the magnetic flux, M is the mutual inductance, is the permeability of the vacuum, 4π × m/H, N is the number of turns, and A is the cross-sectional area of the coil. The voltage induced in the Rogowski coil appears in the relationship between the differential value of the lightning current and the mutual inductance in the down conductor.…”

The Rogowski Coil Technology Advancements: A Review of High Current Applications

“…The coil is placed around current flowing wire for measuring the current as shown in (Fig. 1) (Kawabata, et al, 2013), due to the current flow a magnetic field is generated around the conductor, according to Faraday's induction law the field is converted into a signal, that is proportional to the derivative of the current change which is flowing in the conductor (Nanyan et al, 2018). The rate of current change induces a voltage in the coil, given by…”

A current and vibration based detection system for lightning strikes on transmission towers

“…In the past, many different methods have been proposed for the detection of lightning strikes. Some of these included the use of current transformers [2][3][4] for lightning current detection and measurement whereas others focused on electromagnetic radiation and sound waves in air, which can end up being quite expensive [5] and cannot distinguish strikes directly to towers or lines from strikes in the vicinity.…”

“…In order to derive the formula for the emf in the coil, the flux needs to be calculated. The flux, ϕ, in the cross sectional area of the coil is given by (2). Given a time dependent current I at angular frequency ω, the emf induced in the coil is given by (3) and 4where M is the mutual inductance of the coil.…”