Under-Frequency Load Shedding scheme for islanded distribution network connected with mini hydro

Load shedding scheme based on frequency and voltage stability for an islanding operation of a distribution network connected to mini-hydro generation

“…The loads are categorized as vital, semivital, and nonvital and are ranked according to load prioritization. As reported in [14], nonvital loads, such as residential loads, are given priority to be shed first before vital loads (e.g., hospital or factory loads) during system disturbances.…”

“…In practice, the most commonly applied load shedding scheme (LSS) for islanded distribution systems is the underfrequency load shedding (UFLS) scheme [1,2,[10][11][12][13][14]. In [2], the authors presented an analysis of the frequency gradient in the load-shedding process.…”

“…Multistage UFLS for an islanded microgrid was introduced in [13] with the use of the equivalent inertia constant. In addition, the application to estimate a disturbance magnitude based on the rate of change of frequency (ROCOF) can be found in [11,14]. However, the above-mentioned studies only highlight system frequency as the main factor in the process of load shedding.…”

Adaptive centralized protection scheme for distribution systems with DG using risk analysis for protective devices placement

“…There are different methods of load estimation in distribution networks [18]. Due to the vastness of load estimation topic in distribution systems, this paper has not dealt with it, and for network zoning and operation of load shedding it is assumed that hourly load curves for all substations of distribution network have been estimated before, and are available for performed studies.…”

Multi-stage underfrequency load shedding for islanded microgrid with equivalent inertia constant analysis

“…If H i of each synchronous generator and the df i /dt after disturbance are monitored, then the DP i of each generator can be estimated, and the sum of DP i can be illustrated as follows [5]:…”