Precise 10 and 20 kV DC/AC resistive divider

This paper describes the structure and calibration of a resistive divider for DC voltage measurement in the range up to 10 kV or 20 kV. The divider consists of twenty 9.99 MΩ high-voltage resistors and one 100 kΩ output resistor. Circular electrodes create parallel capacitor to appropriate resistors. These thin-film resistors have a tolerance of resistance 0.1 %. The structure is designed to minimize the influence of corona currents and leakage resistance between resistors. This paper describes resistor calibration process of, including verification of their voltage dependence. The divider ratio constant and its uncertainty are calculated on the basis of this calibration. The advantage of the proposed procedure is in easy divider recalibration process. A simple recalibration process is necessary due to the long term usage. The proposed DC voltage divider can be used to measure AC respective impulse voltages as well. The frequency independency in given frequency range is then required. The application of compensatory capacity and automatic correction method ensure the correct compensation of voltage divider.