Intended and Unintended Islanding of Distribution Grids

Today's electric power systems are complex systems, but every interconnected system can split up into several subsystems due to faults, maloperation or intended islanding due to targeted switching. The questions then arise whether these subsystems are "survivable", and whether the size of these subsystems are random or predefined, and under which conditions can these isolated subsystems be operated in a stable manner. Due to the energy transition a lot more renewable generation units are installed in the distribution grid. This facilitates local intended isolated grids, but also increases the probability of unintended isolated grids. These must be controlled and dealt with. Though the topic of islanding has been increasingly discussed in academia in recent years, this topic has not yet been comprehensively described in any specialist book. This practical reference for Researchers at universities and in industry as well as at grid operators, involved with building, extending or maintaining electricity grids addresses the subject. Chapters cover basics and control of power system dynamics and stability, behaviour at grid connection points, power system restoration, and protection, islanding detection, planning methods for secure islanding, modelling for distribution grid analysis in the time-domain, insular power systems, droop based practical examples, practical aspects of bottom-up grid restoration, and unintended islanded grids.