Research on Screening Method of Operating Risk Points for Power System Pre-Dispatch

2021 ◽  
Author(s):  
Yi Wang ◽  
Ji Zhang ◽  
Qingcheng Liu ◽  
Ling Xu ◽  
Xin Wu
Keyword(s):  
Power System ◽  
Screening Method ◽  
Operating Risk

scholarly journals Research on the Unstable Branch Screening Method for Power System With High-Proportion Wind Power

2022 ◽  
Vol 9 ◽  
Author(s):  
Fei Tang ◽  
Xiaoqing Wei ◽  
Yuhan Guo ◽  
Junfeng Qi ◽  
Jiarui Xie ◽  
...  
Keyword(s):  
Power System ◽  
Wind Power ◽  
Wind Farm ◽  
Simulation Analysis ◽  
Screening Method ◽  
Prediction Method ◽  
Stability Margin ◽  
Screening Methods ◽  
Unstable Branch ◽  
Oscillation Characteristics

The sooner the system instability is predicted and the unstable branches are screened, the timelier emergency control can be implemented for a wind power system. In this paper, aiming at the problem that the existing unstable branch screening methods are lack prejudgment, an unstable branch screening method for power system with high-proportion wind power is proposed. Firstly, the equivalent external characteristics model of the wind farm was deduced. And based on this, the out-of-step oscillation characteristics of the power system with high proportion wind power was analyzed. Secondly, based on the oscillation characteristics, line weak-connection index (LWcI) was proposed to quantify the stability margin of a branch. Then an instability prediction method and an unstable branch screening method were proposed based on LWcI and voltage phase angle difference. Finally, the rapidity and effectiveness of the proposed method are verified through the simulation analysis of IEEE-118 system.

An integrated screening method for evaluating the pulmonary toxicity of inhaled particulates: Role of microscopic techniques in assessing pulmonary macrophage clearance functions

1990 ◽  
Vol 48 (3) ◽  
pp. 826-827
Author(s):  
David B. Warheit ◽  
Lena Achinko ◽  
Mark A. Hartsky
Keyword(s):  
Bronchoalveolar Lavage ◽  
Pulmonary Toxicity ◽  
Screening Method ◽  
Pulmonary Response ◽  
Inhaled Particles ◽  
Cytochemical Analysis ◽  
Pulmonary Macrophages ◽  
Integrated Screening

There is a great need for the development of a rapid and reliable bioassay to evaluate the pulmonary toxicity of inhaled particles. A number of methods have been proposed, including lung clearance studies, bronchoalveolar lavage analysis, and in vitro cytotoxicity tests. These methods are often limited in scope inasmuch as they measure only one dimension of the pulmonary response to inhaled, instilled or incubated dusts. Accordingly, a comprehensive approach to lung toxicity studies has been developed.To validate the method, rats were exposed for 6 hours or 3 days to various concentrations of either aerosolized alpha quartz silica (Si) or carbonyl iron (CI) particles. Cells and fluids from groups of sham and dust-exposed animals were recovered by bronchoalveolar lavage (BAL). Alkaline phosphatase, LDH and protein values were measured in BAL fluids at several time points postexposure. Cells were counted and evaluated for viability, as well as differential and cytochemical analysis. In addition, pulmonary macrophages (PM) were cultured and studied for morphology, chemotaxis, and phagocytosis by scanning electron microscopy.

Sign in / Sign up

Export Citation Format

Share Document