Given that testing of grid components is extremely valuable to assure that every detail works as it should do before installing them in the power system, and in consideration of the increasing needs to guarantee reliable energy to all, KEMA Labs (the CESI Testing, Inspection and Certification Division) together with the TSO Amprion, is now installing in its facility in Mannheim (Germany) the new transformer T401.
The new transformer T401, which was built in the Nuremberg transformer factory of Siemens Energy, will have a short-circuit power of 1000 MVA and rated power of 63 MVA. The new testing transformer is designed for maximum short-circuit current Ik rms of 100 kA and a maximum peak current Ip of 276 kA. Depending on the configuration of the power grid at local supplier substation in Mannheim Rheinau, the short-circuit power of the grid will be within a range of 10 up to 25 GVA.
As the high-power laboratory in Mannheim was and still is designed as a testing station, which feeds the energy for the tests directly from the grid, this requires a substation with sufficient short-circuit power in the neighborhood to avoid effects of the tests on the feeding grid.
Due to a modernization of the current grid in the responsibility of the TSO, Amprion, the 220-kV level in the substation will be omitted and therefore the laboratory would have risked losing its feeding power. To avoid this situation, Amprion decided, together with CESI, to connect the laboratory with an overhead line of the higher 380-kV voltage level.
This means that all towers, lines, switching devices, measuring transformers and – most important – the test transformer must be replaced by new devices suitable for the 380-kV level. Aside from the replacement of the devices, a fire protection concept must be introduced, since the transformer bay will be extended to store the new transformer which has bigger dimensions compared to the 220-kV device, that was used in the past.
The delivery of the new transformer T401 was completed on Friday, November 12th, and the installation of the new test transformer will take three-four months, including the connection to the substation. Furthermore, the control system of the short circuit house, which is installed on the secondary side of the transformer, will be replaced and brought to a new standard. It is a project based on a cooperation between labs development, local KEMA Labs test engineers of the high-power lab in Mannheim and the KEMA Labs engineers of the secondary group in Arnhem, the Netherlands.
Thanks to the new Transformers T401, KEMA Labs upgraded even further its cutting-edge technologies, in order to meet its customers’ needs all around the globe.