High and extra-high voltage systems - the backbone for power supply
High-voltage and extra-high-voltage systems with voltage levels of 110 kV, 220 kV and 380 kV represent the backbone for the supply of electricity to industry and private households.
In order to ensure safe and stable grid operation, it is necessary that the high-voltage grid can withstand all possible internal (switching operations) and external influences (atmospheric discharges).
Picture on the right: gas-insulated switchgear
Targeted switching operations are carried out to change the network configuration in high-voltage systems.
Carrying out targeted switching operations. To change the network configuration in high-voltage systems, switching operations are carried out in a targeted manner. When switching operations are carried out, there is a change between two stationary states and balancing processes occur in the high-voltage system. These balancing processes are characterised by rapid changes in the voltages. The time ranges of the equalisation processes can be in the range of microseconds to milliseconds.
Disconnect circuits. Particularly in the case of isolating circuits in gas-insulated high-voltage systems (i.e. in encapsulated high-voltage systems, see photo above), very rapidly changing voltages with frequency ranges up to the MHz range occur - so-called VFTs (very fast transients).
VFT measurement at voltages in a 380 kV gas-insulated switchgear.