METHOD FOR SIMULTANEOUS MEASUREMENT OF CURRENT AND VOLTAGE ON HIGH-VOLTAGE LINES USING OPTICAL TECHNIQUES

A laboratory device for simultaneous measurement of magnetic and electric fields has been constructed. This should allow corresponding measurement of line current and voltage. A laser beam may be directed upwards from the ground to interrogate a passive optical transducer attached to a high-voltage busbar. Real and reactive power indications can also be obtained from the output, thus providing complete simultaneous information on the line state. The device uses a combination of magneto-optic and electrogyration effects in crystalline alpha -quartz. The latter effect has only recently been discovered and should lead to a device with small temperature dependence. The measurement transducer operates in a differential mode and the light beam passes through the quartz at a chosen angle to the optic axis. Quartz is a rugged material, very suitable for use in a transducer.