Capacitive measurement of high dc voltages

Abstract

This paper describes a new technique for the capacitive measurement of high dc voltages, based on the principle of consecutive differentiation and integration. A measuring electrode acts as the differentiating high-voltage capacitor; the electric flux to the measuring electrode can be intercepted by a movable shield. The signal is integrated with a commerically available integrator. The method has excellent accuracy and linearity, while the long-term stability is determined by the drift of the integrator. Calibration is only necessary after a change in the high-voltage circuit. The system is sensitive to corona, but the onset of corona can easily be observed by the operator. The described principle can also be used to measure 60 Hz and impulse voltages.