Non-contact transient high-voltage measurement with self-integrating D-dot probe

摘要

Online transformer monitoring and protective relaying require voltage sensors with fast response and high precision. Traditional devices, such as resistive and capacitive dividers, have disadvantages in measuring transient voltage, e.g., oscillation, narrow bandwidth, and large size. This paper introduces a new D-dot probe for transient measurement. The difference input circuit structure is presented on the basis of the operating principle of the D-dot probe. Paralleled multiple electrodes are applied to gain the mutual capacitance value of the probe to achieve a large divide ratio and make the probe work in a self-integrating mode. Pspice simulation is conducted to find a way to minimize probe error. The probe is manufactured into printed circuit boards (PCB). The steady state linearity and transient response of the probe are tested. Results show that the probe has fast response and broad bandwidth.