Power system stabiliser capability of offshore wind power plants

Nowadays, wind power generation is being located offshore because of its higher wind speed at lower height and larger installation zones in comparison with onshore technologies. Recently, the concept of wind power plant has been introduced as a result of the increment of wind power penetration in power systems. Transmission system operators are requiring wind power generation to help to power system with some ancillary services such as fault ride through or power system stabiliser capability. Therefore, it is important to study power system stabiliser capability of wind power plants. In this paper, a comparison of various power system stabiliser schemes is presented. The effect of the distance from the shore tie-line to the offshore wind farm on the controller response is also evaluated. These studies show that offshore wind power plants have promising power system stabiliser capability even using local input signals.Postprint (published version

Control and simulation of multi-terminal VSC-HVDC grids for offshore wind integration

Nowadays, High Voltage Direct Current (HVDC) systems based on Voltage Source Converters (VSC) are being installed for integrating the energy of individual offshore wind power plants to the main land AC grid. Moreover, as the number of offshore wind power plants is increasing, the interconnection of the different links in a multi-terminal grid, to increase the system exibility, becomes interesting. In this work, the different elements of a multi-terminal VSC-HVDC grid are modelled, VSC converters controllers are designed and the complete system is simulated employing Matlab Simulink to analyse the operation in different scenarios

Wind power plant resonances

Onshore and offshore wind power plants comprising wind turbines equipped with power converters are increasing in number worldwide. Harmonic emissions in power converters distort currents and voltages, leading to power quality problems. Low order resonances in the collector grid can increase the impact of wind turbine emissions. These resonances may also produce electrical instabilities in poorly damped wind power plants. The paper performs frequency scan with Matlab/Simulink simulations and compares low order frequencies of parallel resonances in onshore and offshore wind power plants. It also investigates the influence of wind power plant variables on resonance. Finally, simplified equivalent circuits of wind power plants are proposed to study low order parallel resonances.Postprint (published version