Исследование температурного поля стержневого и дискового шунта

Abstract

Проведен анализ конструкций токовых резистивных преобразователей, обеспечивающих измерение переменных токов в широком динамическом (до нескольких сот килоампер) и частотном диапазонах. Показан подход к исследованию факторов, влияющих на динамические характеристики стержневого и дискового шунтов. Проведен анализ распределения температурного поля стержневого и дискового шунта в программном пакете Comsol Multiphysics. Показано, что температурные поля стержневого и дискового шунтов имеет неравномерный характер из-за теплоемкости материалов и свободной конвекции.This article is dedicated to current sensor using current shunt. Electric current is an important physical quantity and its measurement is required in many applications, be it in industrial, automotive or household fields. Different technical solutions to measure currents are known and are found on the market. This application note is trying to give an overview of measurement device and show their respective advantages and disadvantages. It turns out that due to galvanic isolation between the sensed circuit and the measuring circuitry, current sensor using Hall effect is a good choice for many applications. But current sensor using Hall effect is not a good choice for high current. Rogowsky coil based on the principle of electromagnetic induction has several advantages, such as simplicity of construction, reliability, low cost, no need in a power source and relatively high sensitivity. Rogowsky coil is a good choice when it is impossible to carry out the installation of the shunt. But it has several disadvantages such as a limit of frequency. The next section looks into some aspects for current sensor designs with current shunt sensors, including choices of body types, designs and materials. A current shunt sensor example is presented. This article analyzes a current shunt sensor designed to conduct a pulse current to an electrical device. The current conducted in the current shunt produces heat due to the resistive losses, a phenomenon referred to as Joule heating. The Joule heating effect is described by conservation laws for electric current and energy. Once solved for, the two conservation laws give the temperature and electric field, respectively.