A novel concept for monitoring partial discharge on EHV-cable system accessories using no active components at the accessories

A sensitive, directional coupling sensor attached to a high-voltage power transmission cable couples enough signal from a partial discharge to an electrooptic modulator to measurably change the amplitude of an optical carrier. The demonstrated sensitivity and bandwidth lead to the design of a very robust system for measuring partial discharge that requires no power at the site of the sensor. System concept and experimental results are shown and future options discussed.