During the design of underfrequencyloadshedding (UFLS) schemes, some simple models for frequency dynamics analysis are obviously inadequate since they do not take system voltage into account.
For exerting the functions of the automatic under-frequencyload-shedding device, setting for the device should be calculated correctly.
为有效发挥自动低频减负荷装置的重要作用，应正确进行装置定值的整定。
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Through analysis of the stability of NanBian power supply system in a steel enterprise, under-frequencyload-shedding plans and regional security and stability control plans are adopted in this paper.