Directly High-Voltage Measuring System Based on Pockels Effect

To measure high voltage up to ± 450 kV in the dc to GHz range, a new optical high-voltage measuring system using a Pockels crystal in a longitudinal modulation arrangement is developed. The maximum measurable voltage for conventional Pockels sensors has been limited by the half-wavelength voltage V_π. In the new system, a two-wavelength dual laser system is introduced to expand measurable voltage up to the least common multiple of V_π for each light. The measured results for dc, ac, lightning impulse, and step voltages by the system are presented and compared with the predicted values.