Method to Determine the Ratio Error of DC High-Voltage Dividers

This paper introduces a method called the “dc voltage summation method” for determining the ratio change of dc high-voltage dividers with the applied voltage. Two auxiliary voltage dividers with the same rated voltage U were used to calibrate the voltage divider with rated voltage 2U. Experimental results showed that the measurement uncertainty of the method can achieve 1 mV/kV at an applied voltage of 100 kV. The ratio change of dc high-voltage dividers caused by the parameter changes of the resistors with applied voltage can be evaluated more accurately when compared to other existing methods. In conjunction with leakage current measurement, this method can be used to provide traceability of dc voltage dividers above 500 kV.