In the vast starry sky of the power system, the voltage transformer (PT) is not very prominent, but it plays a pivotal role. As one of the key equipment for power transmission and distribution, the voltage transformer has become an important cornerstone for ensuring the safe, stable and efficient operation of the power system with its unique functional characteristics.

The main function of the voltage transformer is to transform voltage. However, unlike conventional transformers, the voltage transformer is not designed to transmit electric energy. The main purpose of its voltage transformation is to power measuring instruments and relay protection devices to achieve accurate measurement of line voltage, power and electric energy. This feature makes the voltage transformer particularly important in high-voltage power systems, because it can provide accurate voltage data while ensuring the safety of operators and equipment, and provide strong support for the monitoring, control and protection of the power system.

The basic structure of the voltage transformer is similar to that of the transformer, and it is also composed of an iron core and a winding. However, its capacity is relatively small, generally only a few volt-amperes to tens of volt-amperes, and the maximum does not exceed one thousand volt-amperes. This design not only reduces the size and weight of the equipment, but also reduces the manufacturing cost. During operation, the primary winding of the voltage transformer is connected in parallel to the line, and the secondary winding is connected in parallel to the instrument or relay, realizing the precise conversion from high voltage to low voltage. The voltage transformer also has the function of electrical isolation, which effectively ensures the safety of operators and equipment.

With the development of the power system, the voltage transformer is also evolving, forming a variety of types and specifications. According to the installation location, it can be divided into indoor and outdoor types; according to the number of phases, it can be divided into single-phase and three-phase types; according to the number of windings, it can be divided into double-winding and three-winding voltage transformers; according to the insulation method, it can be divided into dry type, cast type, oil-immersed type and inflatable type. These diverse types enable voltage transformers to adapt to the needs of different voltage levels and different application scenarios, providing a solid guarantee for the stable operation of the power system.

In recent years, with the continuous advancement of science and technology, voltage transformers have made significant progress in intelligent and high-precision measurement. The application of digital technology enables voltage transformers to achieve remote monitoring and data sharing, improving the operation and maintenance efficiency of power systems. At the same time, the application of new materials and sensing technologies has further improved the performance and reliability of voltage transformers. In the construction of smart grids, voltage transformers play an irreplaceable role. By working in collaboration with other smart devices, they monitor the state of the power grid in real time and provide data support for the optimization and dispatching of power systems and fault warning.

Voltage transformers, a seemingly inconspicuous device, play a pivotal role in power systems. With precise voltage conversion, powerful isolation functions and a variety of types and specifications, it provides a strong guarantee for the safe, stable and efficient operation of power systems. With the continuous advancement of science and technology and the continuous growth of market demand, voltage transformers will usher in a broader development prospect.