Electric energy supply and distribution grids will be subjected to enormous changes as a part of the sustainable energy transformation. The change
from generation in large power plants to decentralised sources of energy, means gigantic tasks for high-voltage measurement technology.
HVDC cable lines can be mentioned here as an example. The testing of components of future transmission grids often requires the application of
superimposed voltage forms. These so-called combined or composite voltages are carried out in the test laboratories without sufficient metrological traceability and standardisation. Within the
European Metrology Programme for Innovation and Research (EMPIR) a project was started, named 19NRM07 HV-com², which deals with
traceable measurement of voltages at composite and combined high-voltage tests. This project focuses on new low-voltage generators,
measurement evaluation software and measurement systems up to 400 kV. Traceable high-voltage measurement systems and calibration services for composite and combined waveforms were developed and set up at the
participating national metrology institutes. Several high-voltage intercomparison campaigns were successfully carried out. At the same time, the research results were integrated into the ongoing revision of the IEC 60060 series [01], [02]. This paper presents the results of the project and the standardisation work.