In the vast network of the power system, every flow of current carries the heavy responsibility of energy transmission and conversion. In this complex and sophisticated energy artery, there is an unknown but crucial role - the current transformer (CT). It is like an "invisible detective" in the power world, silently monitoring the dynamics of the current and guarding the safety and stability of the power grid.

In short, the current transformer is a measurement and protection device used in the power system that can convert high current into low current (usually 5A or 1A) in proportion for monitoring, measurement and control. This process is based on the principle of electromagnetic induction, which realizes the isolation and transmission of current signals, ensuring both measurement accuracy and the safety of personnel and equipment.

In the vast power network, the current transformer plays the role of "smart eyes". It can not only accurately measure the actual current value in the line and provide accurate data for electric energy metering, but also is an important source of information for the power grid fault diagnosis and protection system. When abnormal conditions such as overload and short circuit occur in the power grid, the current transformer can quickly sense the current change, trigger the action of the protection device, effectively prevent the accident from expanding, and ensure the stable operation of the power grid.

With the advancement of science and technology, the current transformer has also undergone a gorgeous transformation from traditional to intelligent. Early current transformers mostly used iron core structure, which had saturation problems, limiting their application under extreme conditions. Modern optical current transformers (OCT) and Rogowski coil current transformers use optical effects or magnetic field measurement principles to achieve non-saturated, high-precision, and wide dynamic range current measurement, providing strong technical support for the construction of smart grids.

In particular, optical current transformers, with their advantages of good insulation performance, small size, light weight, and strong anti-electromagnetic interference ability, are gradually becoming the first choice for high-end application fields such as high-voltage direct current transmission and flexible direct current transmission. These technological innovations not only improve the intelligence level of the power system, but also lay a solid foundation for realizing the energy Internet and promoting energy transformation.

Although current transformer technology has made significant progress, it still faces many challenges. With the large-scale grid connection of renewable energy, the volatility and uncertainty of the power system have increased, which has put forward higher requirements for the response speed, measurement accuracy and long-term stability of current transformers. How to reduce costs while ensuring performance is also one of the current research hotspots.

Looking to the future, with the deep integration of technologies such as the Internet of Things, big data, and artificial intelligence, current transformers will become more intelligent and networked. By integrating sensors, microprocessors and communication technologies, real-time data collection, analysis and remote monitoring can be achieved, providing strong support for the refined management, fault prediction and health management of the power system, and promoting the power industry to develop in a more green, efficient and safe direction.