Entity

Time filter

Source Type


Wei L.,South China University of Technology | Guo W.,Guangdong Power Dispatch Center | Wen F.,South China University of Technology | Wen F.,Queensland University of Technology | And 3 more authors.
IEEE Transactions on Power Delivery | Year: 2011

A flood of alarm messages in an automatic digital substation makes the monitoring task a significant challenge for the operators in a remote control center, especially under fault scenarios. An online intelligent alarm-processing system is developed based on the architecture of the digital substation. First, real-time alarms are classified according to the IEC 61850 standard in order to provide synthesized and organized alarms for the alarm-processing procedure in the next step. Then, a new and systematic alarm-processing approach for digital substations is developed. Two modules (i.e., the generation of candidate hypotheses and the truth evaluation for the hypotheses) are included in the developed approach, and these two modules are operating in parallel in online implementation. This approach could not only determine the fault/disturbance cause but also the missing or false alarms as well as the causes of the false alarms. According to actual application requirements, an online intelligent alarm-processing system is developed and applied in the Xingguo substationthe first digital substation in Jiangxi Province, China. Finally, an actual alarm-processing scenario serves to demonstrate the presented alarm-processing method as well as the developed software system. © 2011 IEEE.


Tong S.,South China University of Technology | Wen F.,Zhejiang University | Chen L.,South China University of Technology | Chen L.,Guangdong Power Dispatch Center
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2012

There are usually some noises in the historical load data, and the accuracy of load forecasting could then be impacted. Hence, it is necessary to de-noise the noises before the load data are used for load forecasting or power system analysis. Considering both horizontal and vertical continuities of electric loads, a new method for load de-noising is presented based on a two-dimension wavelet threshold de-noising method. First, the load data is transformed into a matrix of gray-scale images by normalization. Next, the images are processed by employing the two-dimension wavelet threshold de-noising method. Finally, the de-noised data are obtained after de-normalization. The feasibility and efficiency of the developed method are demonstrated by the improvement of the load forecasting accuracy of an actual example. © 2012 State Grid Electric Power Research Institute Press.


Zhang Y.-J.,South China University of Technology | Chen C.,South China University of Technology | Li Y.,Guangdong Electric Power Design Institute | Wu G.-B.,Guangdong Power Dispatch Center
Electric Power Systems Research | Year: 2010

This paper presents a novel optimization model of dynamic voltage support planning. It considers the state transition course after great disturbance of large-scale receiving end networks (REN). The risk of contingency can be equivalent to the annual risk loss and it can be reduced by the appropriate dynamic voltage support. The annual risk loss consists of state separating risk costs and transferring risk costs. The objective function of dynamic voltage support planning is to maximize the yearly average profit of the state without and with additional dynamic voltage support for the power system. The model is able to describe all kinds of voltage instability scenarios caused by REN interior faults or interface failures properly. The optimal schemes of dynamic voltage support planning of Guangdong receiving end power grids in 2008 and 2010 are given as instance based upon the proposed model, which shows that the comprehensive allocation schemes are of great security and economical efficiency. © 2010 Elsevier B.V. All rights reserved.


Zhang Y.,South China University of Technology | Lin J.,South China University of Technology | Yang Y.,Guangdong Power Dispatch Center
Dianli Xitong Zidonghua/Automation of Electric Power Systems | Year: 2011

With large-scale power grids going highly-capacitive, close-coupled and sophisticated, automatic voltage control (AVC) is getting increasingly difficult as can be seen in control mismatch problems between multi-level dispatch centers in engineering practice. The principal manifestations, causes and harm of multi-level voltage control mismatch in large-scale power grids are summarized. Based on an analysis of the essence and mechanism of multi-level voltage control mismatch in large-scale power grids, a game model is presented to describe the problem of multi-level voltage control mismatch. A case study on Nash equilibrium and cooperative game analysis for AVC is employed to show that it's advisable to explain the mismatch mechanism of voltage control and solve the mismatch problem via game modelling. © 2011 State Grid Electric Power Research Institute Press.


Zhang Y.,South China University of Technology | Lin J.,South China University of Technology | Yang Y.,Guangdong Power Dispatch Center
Dianwang Jishu/Power System Technology | Year: 2012

Present research situation of volt/var control and coordination of power system home and abroad is surveyed. The equilibrium state of volt/var control and coordination is summed up and its definition is given; the concepts of uncoordinated/coordinated volt/var control are proposed; the models for equilibrium and coordinated reactive power dispatch (ECRPD) are built and key problems and difficulties in the research on volt/var control and coordination are pointed out. Besides, it is suggested to integerate distributed artificial intelligence approach such as multi-agent system with game theory to analyze and solve ECRPD problem.

Discover hidden collaborations