Investigation of Voltage Stability of Wind Rich Electric Power Systems

With the increasing penetration levels of wind power generation in power systems around the world, it is imperative to understand the impact of wind generators on power system dynamics and stability. Wind generators have distinct characteristics compared to synchronous generators used in conventional power systems, such as the intermittency and limited predictability of wind resources, and utilisation of asynchronous power generators and power electronic converters, which partially or fully decouple the mechanical and electromagnetic dynamics. Due to these distinct characteristics, wind generators can affect stability of existing networks in relation to voltage stability, frequency stability and rotor angle stability. Through a critical review of existing literature related to these areas, it was identified that there are significant research gaps related to voltage stability in wind rich networks, which is the focus of the work presented in this thesis. The main consequence of voltage instability is the inability to meet the reactive power demand of power systems. Voltage stability is affected by the reactive power support available in a network, where generators are the main reactive power sources. Therefore, with the increased penetration levels of wind power generation in power systems, it is important to investigate the capabilities of wind generators to support the voltage stability.