A Measurement Transformer for Establishing Accurate Voltage Division in Thermal Converter Measurements up to 1000 V and 100 kHZ

A self-calibrating measurement transformer for use in a new step-up method to determine the ac/dc transfer errors of thermal converters is described. The transformer is a two-stage inductive voltage divider incorporating a screened secondary, and is designed so that the decade sections have almost ideal symmetry. The voltages of the decade sections can be determined with uncertainties of a few parts × 10-6 at 1000 V and 100 kHz, and with much smaller uncertainties at lower frequencies.