A Computer System: Measurement of Welding Surge Currents

Abstract

This paper presents both the hardware and software for a system for the measurement of welding process electric parameters. The distinctive feature of the system is its application for control of the process of high-quality contact micro-welding of critical destination products, which is characterized by the pulse current in the range from 100A to 20kA and by the pulse duration from a few to hundreds of milliseconds. The system is portable and consists of the measuring coaxial shunt, oscilloscope and computer with software. Structure, modeling and main principles of constructing the system components are described. Its technical and metrological parameters are given.

Multiplicative Method for Reduction of Bias in Indirect Digital Measurement Result

“…4 (curves 3 and 4 appropriately). These graphs are plotted using expressions As it can be seen from Table 2, in spite of a restricted resolution of multimeter V7-22A, the proposed error correction method works and provides enhancement of resistance measurement accuracy by no less than two orders of magnitude, what is in correspondence with the effect predicted by expression (8).…”

“…Shunt resistors have been extensively used in power electronics, see for instance [7,8], due to their low cost and relative simplicity, while providing reasonable accuracy. Current-technology precise AC shunts are implemented with rated resistance from 0.00001 to 100 Ohm at currents of 0.005 A through 500 kA to be applied in the 50 Hz to 1 MHz frequency range [9].…”

Modeling of Resistive Type Superconducting Fault Current Limiter

“…This makes the choice of reduced superconductor material safer, which decreases volume and total conduction damages. Regarding purposes of the thermal or electric-magnetic behavior, paper [ 9 ] suggests a modern finite component framework for the integrating the electrical and thermal equations throughout the -single solver for a high-temperature superconductor‖. The coated conductor is a structural conductor that influences the existing restricting attributes of surface materials, HTS, ground, etc.…”

“…A system that represents a trendy study of superconducting technology [7] used to develops focusing on the initiative of the -European project ECCOFLOW‖ [8] and implemented in electrical networks. Its main purpose is to design current limiter circuit based on the second-generation high temperature (HTS) [9] cable and is named SFCL.…”

Calculation of resistive current transducer parameters

“…In order to register such parameters, resistive current transducers are applied. Due to their low cost, good metrological performance, and ease of production, coaxial shunts are usually used as irregular shaped pulse current supplies [1].…”