Low frequency and low voltage load shedding schemes for East China Power Grid

Study on united under-frequency load shedding scheme of China Southern Power Grid based on frequency security quantitative analysis;

Development and application of power system under-frequency load shedding analysis software package;

Study on optimal setting of under-frequency load shedding in power systems;

In this paper the definition of over shedding caused by under frequency load shedding and the concept of urgent step are given, the reasons causing over shedding are classified.

Undoubtedly, the under frequency load shedding (UFLS) is an effective method to restrain frequency drop and most of UFLS devices use pre specified step to shed loads according the measured value of frequency.

Existing UFLS(under frequency load shedding)function is always contained in line protection device,when the system frequency reduce to the threshold of frequency setting,with the slip and low-voltage block,UFLS function act to reduce system load and keep the balance of power system.

Reserch on Setting Online of UFLS Equipment;

Development and Application of Shandong Grid UFLS Scheme Calculation Software;

UFLS Online Optimization Setting Based on Multi-Generator System;

A model of under-frequency load shedding(UFLS),which is available in the mi.

In this paper, the actions of main and backup protections and under frequency load shedding(UFLS) as well as under voltage load shedding(UVLS) are simulated in detail.

As a consequence,under frequency load shedding(UFLS) very often disconnects more or less load than is required,so there is a need for the development of an adaptive UFLS plan.