With this invention, corona inception voltage in uninsulated overhead lines is detected by placing a sensitive direct current galvanometer in position to detect the change from negative to positive space charge around the overhead conductor when corona discharge begins. The galvanometer, with low pass filters, is placed in series with the power line, and the low pass filters prevent the relatively heavy capacitive alternating current from flowing through the direct current galvanometer coil.
A method and detector for monitoring electrical strikes along a power transmission distribution system are described. The method and detector identify the location within the transmission system where an insulator flashover event has occurred. The method includes sensing the magnetic field about the live transmission line(s) upstream and downstream from each transmission tower and providing signals representative of the upstream and downstream magnetic fields. These signals are then compared and a flashover event signal is provided whenever the signals representative of the magnetic fields differ about a tower. The event signal identifies the tower within the system on which the insulator flashover occurred. A detector corresponding to the method is also provided.
A device to remove the dead band in atmospheric electric potential measurements while maintaining a low leakage path to ground. In one embodiment the device comprises a AC high voltage source connected through a high ohm resistor and capacitor network to a sharp corona point and a means for measuring the current through the corona point.
