The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of th...The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of the system.Therefore,this work proposes a new methodology to study the fault-generated high frequency transient signals in transmission lines through multiresolution analysis.The high frequency components are determined by a new digital filtering technique based on mathematical morphology theory and a spectral energy index.Consequently,wide spectra of signals in the time–frequency domain are obtained.The performance of this method is verified on an electrical power system modeled in ATP-Draw,where simulation and test signals are developed for different locations,fault resistances,inception angles,high frequency noises,sampling frequencies,types of faults,and shapes of the structuring element.The results show the characteristics of the fault such as the traveling wave frequency,location,and starting time.展开更多
High penetration of renewable energy sources(RES)leads to new challenges for protection devices.Protection schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,wh...High penetration of renewable energy sources(RES)leads to new challenges for protection devices.Protection schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not considered.Consequently,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the RES.Therefore,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria solutions.This work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through inverters.Bibliographic data on many representative publications related to this topic are obtained to show the current research lines and their proposed solutions.In addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider RES.Finally,an analysis and discussion of the selected bibliography are presented.展开更多
文摘The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of the system.Therefore,this work proposes a new methodology to study the fault-generated high frequency transient signals in transmission lines through multiresolution analysis.The high frequency components are determined by a new digital filtering technique based on mathematical morphology theory and a spectral energy index.Consequently,wide spectra of signals in the time–frequency domain are obtained.The performance of this method is verified on an electrical power system modeled in ATP-Draw,where simulation and test signals are developed for different locations,fault resistances,inception angles,high frequency noises,sampling frequencies,types of faults,and shapes of the structuring element.The results show the characteristics of the fault such as the traveling wave frequency,location,and starting time.
基金supported in part by the German academic exchange service (DAAD)and CONICET.
文摘High penetration of renewable energy sources(RES)leads to new challenges for protection devices.Protection schemes are typically designed according to the dynamic behavior of rotating machines as generation sources,while the RES dynamic response,mainly governed by inverters,is not considered.Consequently,some relevant algorithms of transmission line protection are experiencing challenges because of the fact that magnitude and phase angle com-parison,amount of negative-sequence,and short-circuit current level are affected by the RES.Therefore,an in-depth study of this issue is necessary,one which considers the main causes and new methodological criteria solutions.This work presents an extensive literature review of the evaluation of electrical protection performance and the effects of RES connected to a power grid through inverters.Bibliographic data on many representative publications related to this topic are obtained to show the current research lines and their proposed solutions.In addition,this work identi-fies the main protection functions affected and describes the new protection schemes that consider RES.Finally,an analysis and discussion of the selected bibliography are presented.