| （英） |
The electro-optic sensors for measuring electrical environment have the advantages of offering less field distortion and wide frequency responsibility and minimizing electromagnetic interference errors. A Pockels sensor, which is one of these sensors, was applied to the electric-field, potential and charge measurement in Laplacian and Poissonian fields for the first time in the world in the early 1980s. Since then the idea of Pockels sensors has been widely recognized in the world. Innovation of electrical and optical techniques enables to maximize the measurement sensitivity of the sensors and to improve time and space resolution of them. A sensing technique based on Kerr effect of gas was also developed in the early 2000s and has been applied to the noncontact electric-field measurement in gas space.
From a viewpoint of application to electric power networks, Pockels voltage sensors have started to be introduced into gas-insulated switchgears (GIS) since 1980s and the long-term field tests on their use have been carried out. A GIS in a 1000kV transmission line system, which is one of highest voltage power systems, has been also equipped with the Pockels sensors. In other applications, electric field measurement has been made in electrical discharge spaces, which are too faint to be observed, by employing the achievement that the temporal and spatial resolutions of sensors reach nanoseconds and tens micro-meters, respectively. |