Coordinator: Alf-Peter Elg

One aim of this project is to extend the metrological capabilities for calibration of instrument voltage transformers up to 1200 kV and for testing of system components up 1600 kV, and where possible to 2000 kV, to be used in future ultra-high voltage direct current (UHVDC) grids with system voltages currently up to 1100 kV.  

High voltage power systems are tested to prove their ability to withstand diverse fault conditions, including power frequency overvoltage, lightning and switching impulse voltage, and in some cases also the combination of such stresses. As system voltages are increasing to cope with increased power demand in the society and currently, this project tackles the lack of traceability of measurement of direct current (DC) above 1000 kV. 

The current state of the art for DC traceability is a modular divider for on-site calibration up to 1000 kV. The measurement uncertainty of this modular divider is 20 µV/V, which is sufficiently low to calibrate reference measurement systems used for testing purposes. Up to 1000 kV, this reference measurement system is also accurate enough for calibration of reference measurement systems used for calibration of DC voltage instrument voltage transformers. However, calibration facilities for DC voltage above 1000 kV are completely lacking. 

For more information, see the project webpage >>