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Techniques for ultra-high voltage and very fast transients


This project focuses on pre-normative research required for measurements and testing of Ultra High Voltage (UHV) equipment with emphasis on direct current (DC) applications. UHV is the common denominator between the three areas being addressed in this project, which are measurement of composite DC wave shapes, very fast transients, and fault detection. Future high voltage (HV) and ultra‑high voltage (UHV) grids need support for progress beyond the state of the art in terms of measurement techniques for DC applications. This project provides IEC TC38, TC42, TC62C and related standardization groups with methods to develop standards for medical X-ray equipment, measurement of very fast transients (VFT) and  partial discharge (PD) measurements for DC, all areas with an impact on the electrical power industry.


The x-ray voltage measurement activities in this project will benefit from the divider design experience gained in EMRP ENG07 HVDC. This knowledge will be used to take a first step in the measurement of DC switching, which will prepare the way for the development of the new methods needed for the traceable measurement of UHV grid component testing.

Switching in general has an unknown effect on the instrument transformers and sensors used for gas insulated system (GIS) applications, both in terms of very fast transient over‑voltage (VFTO) on the low voltage side in existing HV grids and to an even larger extent in planned UHV grids. New procedures for partial discharge (PD) measurements in DC grids and the traceability for ultra-sensitive PD calibrators will be addressed. Future UHV grids, with emphasis on DC grids, will need methods for detection of PD and determination of the source.