Expert discussions for exclusion of risks through sub-synchronous resonances
New technologies in the transmission grid, e.g. the increasing use of frequency converter, are changing the usual system interactions between power plant and grid and can have a negative impact on the power plant components. Specifically the question arises, if feed-in stations of HVDC connections (HVDC: High Voltage Direct Current) from offshore wind parks or the planned main terminals of HVDC transmission lines can have a direct impact on the turbo sets of power plants nearby located.
The dangers caused by sub-synchronous resonances are real and require communication with the transmission system operators about the interface between power plant and grit, a monitoring of network activities and a coordination of the VGB members' interest.
The topic “Sub-Synchrnous Torsional Interaction (SSTI) was discussed in several expert discussions together with transmission system operators, power plant operators, universities and manufacturers. Currently, the research demand is analysed, concrete actions are aligned and appropriate working groups are set up.
A guideline summarising alignment process and common understanding of power plant operators, system operators and HVDC operators is planned.