Reference calibrator for combined and composite high voltage impulse tests

This paper describes the design and characterization of a reference calibrator, able to generate any type of reference wave shape, such as AC, DC, LI, SI, combined, or composite, up to 900 V. This reference calibrator has been developed at the French National Metrology Institute (LNE), using a novel approach, based on a linear high voltage amplifier. For combined and composite wave shapes, there are no reference or commercial calibrators available on the market nor at National Metrology Institutes. This reference calibrator will enable required calibration capabilities to be created to accurately determine the uncertainty in the calibration of combined and composite wave shapes, and fulfil the requirements of the IEC 61083-1 standard. Further experiments have been performed in order to evaluate the calibrator performances, for impulses as fast as LI, as slow as SI, and combined and composite wave shapes, during which LI or SI are superimposed on AC or DC voltages. Furthermore, two methods have been proposed to demonstrate the calibrator traceability to the international system of units, up to 900 V. This study will contribute to the preparation of voltage testing standardization with combined and composite wave shapes for the forthcoming revision of the IEC 61083-1 standard.