An active high-voltage divider with 20 μV/V uncertainty

A voltage divider has been developed consisting of an external compressed-gas capacitor, a group of stable solid-dielectric capacitors, and special electronic circuitry. A developmental prototype divider has been constructed and test results obtained to verify the operating principle and accuracy target. The new critical items enabling the desired performance are the solid-dielectric capacitors in the low-voltage arm, approaching the short-term stability of gas insulated capacitors, and the active circuit consisting of a feedback amplifier, complemented with a controlled source, which essentially removes the error contribution from the feedback amplifier