Control of wind power plants utilizing voltage source converter in high impedance grids

Challenging wind power projects can be confronted by very low short circuit ratio (SCR <; 4) and sometimes even extremely low ratio (SCR <; 2). Wind power plants (WPP) feeding in their power by means of voltage source converters (VSC) have the potential to be operated in those high impedance grids to a certain extent if they are appropriately controlled. The physical boundaries are well known and referred to as voltage collapse and loss of angle stability (generic: loss of stability, LOS). Measurements and simulations indicate the potential of advanced wind turbines (WT) based on VSC to approach the ultimate physical LOS limits very effectively. This could provide additional opportunities for wind power projects at sites, which may so far not be utilized without grid reinforcement.