This paper has an objective to show a developed quantitative criterion,based in two mathematical variables that explicit the deviation degree of a normal situation,applying simultaneously data from terminal impedances...This paper has an objective to show a developed quantitative criterion,based in two mathematical variables that explicit the deviation degree of a normal situation,applying simultaneously data from terminal impedances and frequency response.Based in more than 100-measured equipment,of different applications(step-up transformer,transmission transformer,etc.,),for a period of 10 years,the work presents some examples of practical application of this methodology in Brazilian Electrical System.展开更多
With modern power utilities going green by utilising renewable energy technologies and the development of the smart power grid,high-voltage direct current(HVDC)technologies become more and more important in the energy...With modern power utilities going green by utilising renewable energy technologies and the development of the smart power grid,high-voltage direct current(HVDC)technologies become more and more important in the energy transmission.In particular,HVDC cable systems play a prominent role in undersea power transmission and offshore renewable energy integration.As an essential part of a complete HVDC cable system,the cable termination is one of the most critical components.The mathematical and physical background of HVDC cable systems is discussed and the development of various types of HVDC cable terminations is reviewed.Regarding the non-uniform field distribution,the influence of temperature on the non-linear conductivity is briefly discussed.Furthermore,faults of terminations caused by inappropriate installation and testing of cable systems are discussed.展开更多
文摘This paper has an objective to show a developed quantitative criterion,based in two mathematical variables that explicit the deviation degree of a normal situation,applying simultaneously data from terminal impedances and frequency response.Based in more than 100-measured equipment,of different applications(step-up transformer,transmission transformer,etc.,),for a period of 10 years,the work presents some examples of practical application of this methodology in Brazilian Electrical System.
基金the National Key Research and Development Program of China in its project entitle‘Critical Technologies for Designing and Manufacturing±500 kV DC Cables and their Accessories’(grant no.2016YFB0900703).
文摘With modern power utilities going green by utilising renewable energy technologies and the development of the smart power grid,high-voltage direct current(HVDC)technologies become more and more important in the energy transmission.In particular,HVDC cable systems play a prominent role in undersea power transmission and offshore renewable energy integration.As an essential part of a complete HVDC cable system,the cable termination is one of the most critical components.The mathematical and physical background of HVDC cable systems is discussed and the development of various types of HVDC cable terminations is reviewed.Regarding the non-uniform field distribution,the influence of temperature on the non-linear conductivity is briefly discussed.Furthermore,faults of terminations caused by inappropriate installation and testing of cable systems are discussed.
