What Are The Components of A Current Transformer

The current transformer is mainly composed of the following key components:

Iron core: The iron core is the core component of a current transformer, usually made of stacked silicon steel sheets. Its main function is to provide a closed magnetic circuit, allowing the current flowing through the primary winding to generate alternating magnetic flux, which will pass through both the primary and secondary windings simultaneously.

Primary winding: The primary winding is directly connected in series with the primary system and can pass a larger primary current. When a current flows through the winding, alternating magnetic flux is generated in the iron core.

Secondary winding: The number of turns in the secondary winding is usually more than one, and it induces the induced electromotive force generated by the alternating magnetic flux generated by the current in the primary winding. When the secondary winding is connected to a load, current flows in the secondary circuit. This secondary current is proportional to the primary current, and the magnitude of the ratio depends on the turns ratio of the primary and secondary windings.

Terminal block: A terminal block is a component that connects a current transformer to an external circuit, used to connect the primary winding and secondary winding separately to the power system.

Insulation support: As the primary winding of the current transformer is directly connected to the primary system, insulation support corresponding to the primary high voltage must be used to ensure the personal safety and equipment safety of personnel working on the secondary circuit.

In addition, according to specific design and application requirements, current transformers may also include other auxiliary components such as frames and shells to provide necessary mechanical support and protection.

Overall, current transformers achieve the function of converting high voltage and high current into low voltage and low current through the collaborative work of these components, providing important support for relay protection and electrical measurement in power systems.