Design and experiment of 200-500A/5A wide-range electromagnetic current transformer based on improved 1K107 material

The measurement error caused by the large range of power load changes is relatively large. Therefore, the problem of economic loss is caused. In this paper, the wide-range current transformers with a rated primary current of 200-500A are designed. It can meet the accuracy requirement of 0.2S in the range of 0.1%~200% of the rated current. In order to achieve this goal, this paper firstly improves the traditional 1K107 material. The improved core material greatly improves the initial magnetic permeability, which can improve the measurement accuracy of small primary currents. Several prototypes were made and experiments were carried out. It was found that the designed wide-range current transformers met the accuracy requirements of 0.2S within the range of 0.1% to 200% of the rated current.