In the huge power system, voltage transformer (VT) plays a vital role. As a special transformer, the main function of voltage transformer is to convert high voltage signal into low voltage signal for detection, measurement and protection. This conversion process not only ensures the safe and stable operation of the power system, but also provides accurate and reliable voltage information for operators.

Voltage transformer, also known as voltage transformer, is a device that works on the principle of electromagnetic induction. Its primary winding has more turns and is connected in parallel with the high voltage grid to be measured; while the secondary winding has fewer turns and is connected to the voltage coil of the voltmeter or power meter. This design enables the voltage transformer to generate different primary voltage to secondary voltage ratios by changing the number of turns of the primary or secondary winding, just like a step-down transformer.

In the power system, there is a great safety risk in directly measuring high voltage, so the application of voltage transformer becomes indispensable. It can convert high voltage into a safe and measurable low voltage for use by measuring instruments, protection equipment and control systems. In this way, operators can safely and accurately obtain voltage information of the power system, thereby ensuring the normal operation of the power system.

Voltage transformers are widely used in power systems. In terms of voltage measurement, it can convert high voltage on the transmission line into a lower measurement voltage for use by measuring instruments. In this way, operators can monitor the voltage changes of the power system in real time, and promptly detect and deal with abnormal conditions.

In terms of voltage protection, voltage transformers also play an important role. When voltage abnormalities (such as overvoltage or undervoltage) occur in the power system, the protection equipment connected to it will act quickly to cut off the faulty part to prevent equipment damage and accident expansion. This function is essential for the safe and stable operation of the power system.

Voltage transformers are also used to isolate instruments and devices under test, especially in high-voltage circuits, where they can effectively protect measuring equipment from high voltage damage. At the same time, in low-voltage circuits, voltage transformers can also isolate interference and improve measurement accuracy.

Voltage transformers can be divided into many types according to their structure and working principle. Among them, electromagnetic voltage transformers and capacitive voltage dividers are two common types. Electromagnetic voltage transformers use the principle of electromagnetic induction to convert voltage, and have the advantages of simple structure and high reliability; while capacitive voltage dividers use the principle of capacitive voltage division to measure voltage, and have the characteristics of wide measurement range and high accuracy.

With the continuous development of science and technology, new voltage transformers are also emerging. For example, optical voltage transformers use optical principles to measure voltage, and have the advantages of high measurement accuracy and strong anti-interference ability; while digital voltage transformers use digital technology to realize the collection and processing of voltage signals, and have the characteristics of intelligence and networking.