Improvements in the PSB AC-DC transfer capabilities and a proposal for range extension

A new automated AC-DC transfer calibration system based on thin-film multijunction thermal converter as primary standards at low-frequency range 10 Hz to 1 MHz has been designed and developed. Range extension up to 1000 V is achieved using resistive voltage divider. An equally-divided range extension setup which can be self-calibrated under practical working conditions has been proposed and eliminate the need of voltage interpolation.