Control interactions resulting from converter interfaced generation
The power electronic converters can interact with other grid components and lead to unstable oscillation in a wide frequency range, for instance, the subsynchronous and high-frequency oscillations. In the past decade, several subsynchronous control interaction (SSCI) events have been reported around the world, including those in Xcel Energy, ERCOT, Guyuan, and Hami wind power systems in the US and China. This chapter first provides a brief overview of the occurrence mechanisms and features of the real-world SSCI events. Then, it discusses the impedance-based analysis and control of SSCI in actual wind power systems.
Oscillatory Stability of Converter-Dominated Power Systems
Electrical power systems worldwide are witnessing an increasing share of power electronic converter-based devices in the form of wind turbines, photovoltaics, flexible ac/dc transmission systems, battery energy storage systems, and distributed generations. Due to the multi-time scale dynamics of their control systems, different converter-based devices and their controls are prone to interact with each other and other components of the power system. The control interactions can lead to “oscillations” with the frequency ranging from a fraction of hertz to several kilohertz, depending on the control design, parameters, and system operating conditions. These oscillations resulting from converter controls are known as wideband oscillations (WBOs).
This book is the first of its kind on the oscillatory stability of converter-dominated power systems.
