New Method for the Determination of Voltage Dependency of High- Voltage Capacitors

For the measurement of high AC voltages mainly voltage transformers or capacitors are used. Capacitors are either set up as voltage dividers, in conjunction with a voltage transformer or other means in order to obtain a lower output voltage. In national metrology laboratories compressed gas capacitors are used as references for calibration purposes. The main influences on the capacitance therefore need to be clearly determined. The voltage dependency is the most significant and challenging uncertainty component up to now. This paper will discuss a new method for the direct voltage dependency determination of any capacitor design. Existing methods mainly depend on the tracking of electrodes in capacitors based on Schering-Vieweg setup. This new method considers all factors influencing the voltage dependency, not only the electrode shifting due to the electrical field.