The developments in power transmission via HVDC networks are fast,especially in Western Europe and China.The challenges that we are confronted with are huge and considerable research and development efforts are requir...The developments in power transmission via HVDC networks are fast,especially in Western Europe and China.The challenges that we are confronted with are huge and considerable research and development efforts are required.Special attention is needed for high voltage direct current(HVDC)and ultra-high voltage dc(UHVDC)underground cables.For the highest voltage levels,we are still dependent upon classic technology based on mass-impregnated paper used in line commutated converter(LCC)systems.Gradually,more and more polymeric type cables are appearing on the market,as yet mainly for voltage source converter(VSC)systems.For financial,environmental and technical reasons the full focus is now on polymeric type cables,for use in LCC or VSC systems.In this paper,a closer look is taken at the interfaces in polymeric cable systems,i.e.in the cables and in the cable accessories.In the design process,we are challenged by the presence of interfaces from an electrical and thermal point of view.In the field of electrical insulation,the interfaces between different materials are generally considered the weakest parts of the equipment and under DC stresses the situation becomes even more complex due to the charge dynamics at the interface.Indeed,the design of(U)HVDC accessories has become a challenge if not a problem.This paper focuses on some of the important electrical and thermal aspects of interfaces in HVDC polymeric cables.It is discussed where we lack knowledge and where we may benefit from other scientific展开更多
文摘The developments in power transmission via HVDC networks are fast,especially in Western Europe and China.The challenges that we are confronted with are huge and considerable research and development efforts are required.Special attention is needed for high voltage direct current(HVDC)and ultra-high voltage dc(UHVDC)underground cables.For the highest voltage levels,we are still dependent upon classic technology based on mass-impregnated paper used in line commutated converter(LCC)systems.Gradually,more and more polymeric type cables are appearing on the market,as yet mainly for voltage source converter(VSC)systems.For financial,environmental and technical reasons the full focus is now on polymeric type cables,for use in LCC or VSC systems.In this paper,a closer look is taken at the interfaces in polymeric cable systems,i.e.in the cables and in the cable accessories.In the design process,we are challenged by the presence of interfaces from an electrical and thermal point of view.In the field of electrical insulation,the interfaces between different materials are generally considered the weakest parts of the equipment and under DC stresses the situation becomes even more complex due to the charge dynamics at the interface.Indeed,the design of(U)HVDC accessories has become a challenge if not a problem.This paper focuses on some of the important electrical and thermal aspects of interfaces in HVDC polymeric cables.It is discussed where we lack knowledge and where we may benefit from other scientific
