a current transformer

Abstract

The invention discloses a current transformer, belonging to the technical field of measurement and aiming to improve the precision in metering electric energy and reducing the leakage rate of electric quantity. In a technical scheme provided by the invention, the current transformer comprises an ultracrystalline iron core, a silicon-steel sheet compensated iron core and a secondary winding, wherein the ultracrystalline iron core and the silicon-steel sheet compensated iron core are both annular and are coaxial, only one part of the secondary winding is wound on the ultracrystalline iron core, and the rest part of the secondary winding is wound on the ultracrystalline iron core and the silicon-steel sheet compensated iron core at the same time. According to the invention, the silicon-steel sheet compensated iron core is additionally arranged on the basis of the traditional current transformer, because the silicon-steel sheet iron core is difficult for saturation, the metering precision of the current transformer under an overload state is improved greatly, so that the leakage rate of electric quantity is reduced effectively and the charging of electric energy is more fair.

Description

technical field [0001] The invention relates to a current transformer with high measurement accuracy, which can effectively reduce the electricity leakage rate, and belongs to the technical field of measurement. Background technique [0002] In order to reduce the power loss, the electric energy metering device generally adopts the ultramicrocrystalline iron core transformer, because the unit loss of the ultramicrocrystalline iron core is much lower than that of the silicon steel sheet and has good excitation characteristics and temperature stability. However, the ultramicrocrystalline iron core transformer has the disadvantage that the magnetic flux is easily saturated. Once the line load exceeds 120% of the rated value, the iron core will enter the saturation region, and the ratio difference of the transformer will increase, resulting in the loss of metered electricity. cause undue loss. Although this problem can be solved by increasing the cross-sectional area of ​​the i...

AI Technical Summary

Problems solved by technology

However, the ultra-microcrystalline iron core transformer has the disadvantage that the magnetic flux is easily saturated. Once the line load exceeds 120% of the rated value, the iron core will enter the saturation region, and the ratio difference of the transformer will increase, resulting in the loss of metered electricity. cause undue loss

Although this problem can be solved by increasing the cross-sectional area of ​​the iron core, this will inevitably lead to an increase in the cost of the transformer

Therefore, how to effectively solve the problem of easy saturation of ultramicrocrystalline iron core transformers without increasing the cost of transformers has become a problem faced by relevant technical personnel.

Images