(1) Wide transient response range and strong harmonic measurement capability
The pros and cons of transient characteristics are an important parameter for judging whether a transformer can be used in the power system, especially the coordination with the action time of the relay protection. Traditional electromagnetic transformers have poor response characteristics to high-frequency signals due to the existence of iron cores, and cannot accurately reflect the transient process on the primary side. The frequency range of the photoelectric transformer is mainly determined by the electronic circuit part, and there is no problem of iron core saturation, so it can accurately reflect the transient process of the primary side. Generally, it can be designed to 0.1 Hz to 1 MHz, and special can be designed to 200 MHz bandpass. The structure of the photoelectric sensor can measure harmonics on high-voltage power lines. The electromagnetic induction transformer is difficult to achieve.
(2) Digital interface, strong communication ability
Since the photoelectric sensor transmits the optical digital signal, it is easy to interface with the communication network, and there is no measurement error in the transmission process. At the same time, with the widespread adoption of microcomputerized protection and control equipment, the photoelectric transformer can directly provide digital quantities to the secondary equipment, so that the converter and A/D sampling part in the original protection device can be omitted, so that the secondary equipment can obtain Great simplification, to promote the research of new principles of protection.
(3) Small size, light weight, and easy to upgrade, meeting the requirements of miniaturization and compactness of substations
Since photoelectric sensors rely on sensor heads and electronic circuits for signal acquisition and processing, they are small in size and generally weigh less than 1000 kg. They are easy to integrate in AIS or GIS. This will greatly reduce the footprint of the substation and meet the miniaturization of the substation. And compactness requirements. At the same time, the photoelectric transformer is connected with the secondary equipment through a small number of optical cables, which can greatly reduce the cable trench and cable.