Self-calibratable voltage transformer with part-per-million accuracy

The design and construction of a 1000 V/100 V, two-stage voltage transformer with burden compensation, which has errors of no more than a few parts per million over its working range of voltage levels and burdens, is described. By dividing the primary winding into ten equal sections and by enclosing the primary and secondary windings in electrostatic screens, it is shown that the transformer can be self-calibrated by a build-up technique, without reference to standard transformers or other potential dividers