Measurement of currents and floating potential in multilayer sensor due to oil-flow electrification

This paper presents floating potential and current measurements due to oil-flow electrification inside a multilayer sensor incorporated in a closed loop filled with fresh transformer oil. All leakage currents at the sensor inlet and outlet, the capacitive current and the streaming current are measured. The waveforms of these currents, floating potential as well as the oil temperature at the sensor inlet are simultaneously recorded for laminar flow and at controlled operating conditions. The measured floating potentials are compared with the calculated ones under different oil-flow velocities and good agreement has been found.