484 / 2022-03-16 19:25:56

Characterisation of a new reference UHVDC divider for traceable calibration up to 1600 kV.

dc voltage divider, High Voltage, UHV, calibration, metrology

In a European research project, 19ENG02 FutureEnergy, with eleven partners from National Metrology and industry, traceability for calibration and measurement technology for component testing of future high and ultra-high voltage grids is being developed. One of the goals in the work package "UHVDC calibration and testing" is to design a new reference divider for traceable calibration up to at least 1600 kV and possibly even 2000 kV. This divider needs to be modular, compact, easy to handle for on-site calibration purpose and have a sufficiently low measurement uncertainty of at least 200 μV/V. For these purposes, two existing modular precision voltage divider designs have been studied. The precision 1000 kV modular HVDC divider, earlier developed in the European research project ENG07 "Metrology for HVDC”, is now extended to 1200 kV for precision calibrations of instrument transformers. Its 200 kV modules could be stacked to reach 1600 kV (2000 kV), but the conservative design would make such a divider 17 m high if it would be extended to 2000 kV. A more practical divider design is a voltage divider concept developed by PTB. It consists of 400 kV modules each 2.4 m high, which gives a total height of 13 m for 2000 kV. This divider design also has a capacitive shield as the modular precision divider, and in addition parallel capacitance mounted in the precision resistance stack.

In this paper the temperature behaviour of four 400 kV modules of the developed divider as well the results of the calibration using the Hamon Transfer is described. The investigations were carried out in the high-voltage laboratory and the high-voltage temperature chamber of PTB. The results of the investigations confirm the capability of the assembled modules as parts of a modular UHVDC voltage divider for voltages up to 2000kV and a measurement uncertainty below 200µV/V.