In 2009 a dynamic interaction between wind turbine structure and connected electrical network was witnessed in Texas when a DFIG was connected directly with a series compensated line during an outage. During this event the wind turbines were damaged through excessive current [1].  The occurrence of sub-synchronous resonance (SSR) in the future GB network as a result of increasing onshore series compensation can neither be confirmed nor ruled out without in-depth technical study.  The GB network is very unique in respect of topology, proximities of these compensations and wind farms. The classic IEEE benchmark model in such a situation falls far short to reflect the reality.

The project will investigate dynamic interaction between series capacitors in transmission circuit and large wind farm generators and control and their impact on the stability of the grid.  It will focus on modelling of reduced GB system for SSR study. The major consideration will be modelling of interaction between series capacitor and wind farm and its control. Two technologies of wind generation, Type 3 (DFIG) and Type 4 (FCIG) will be targeted.  The final objective is to tune wind farm control to mitigate the impact of SSR if identified in the GB system [2,3].

stefy fig
Figure 1 IEEE SSR test system for DFIG and full converter interaction study

[1] J. Adams, C. Carter and S.-H. Huang, “ERCOT Experience with Sub-Synchronous Control Interaction and proposed remediation”, Transmission and Distribution Conference and Exposition, 2012
[2] L. Fan and Z. Miao, “Mitigating SSR Using DFIG-Based Wind Generation”, IEEE Transactions on sustainable energy, vol. 3, issue 3, July 2012
[3] S. O. Faried et al., “Utilizing DFIG-Based Wind Farms for Damping Subsynchronous Resonance in Nearby Turbine-Generators”, IEEE Transactions on Power Systems, vol. 28, issue 1, February 2013.

People

  • Bikash Pal  
  • Stefanie Kuenzel

External people

  • Liena Vilde, National Grid