Phase-oriented control structure for grid stabilization in symmetrical and asymmetrical grid states

Inhalt:
More and more power electronics devices can be found in transport and distribution grids. This is mainly a consequence of integrating more and more renewable energy sources. Grid planning and grid codes have to accept these challenges – especially in the case of asymmetrical faults, but also considering grid stability in general. Suitable assessment strategies and control concepts are needed. This paper concentrates on the control of power-electronic converters connected to the grid and pays special regard to asymmetrical faults. It demonstrates in which way a highly dynamic and robust control is achieved also under these conditions. The proposed concept applies phase-wise modelling in converter-oriented coordinates and relies on the concept of pole restraining.