Power Oscillation Damping from VSC-HVDC connected Offshore Wind Power Plants

The implementation of power oscillation damping service on offshore wind power plants connected to onshore grids by voltage source converter based high voltage direct current transmission is discussed. Novel design guidelines for damping controllers on voltage source converters and wind power plant controller are derived, using phasor diagrams and a test network model and are then verified on a generic power system model. The effect of voltage regulators is analysed, which is important for selecting the most robust damping strategy. Furthermore, other often disregarded practical implementation aspects regarding real wind power plants are discussed: (i) robustness against control/communication delays, (ii) limitations due to mechanical resonances in wind turbine generators, (iii) actual capability of wind power plants to provide damping without curtailing production and (iv) power ramp rate limiters.