Solid state circuit breakers(SSCBs)based on fullcontrolled devices such as IGBT and based on half-controlled devices such as thyristor have their respective advantages.The mixture device solid state circuit breaker(M-...Solid state circuit breakers(SSCBs)based on fullcontrolled devices such as IGBT and based on half-controlled devices such as thyristor have their respective advantages.The mixture device solid state circuit breaker(M-SSCB)combines the advantages together and can achieve lower loss,high efficiency,active and reliable blocking at the same time.However,the conduction loss will increase significantly when the topology expanding to a bidirectional topology because the bidirectional line commutation switch(LCS)structure composed of two groups of IGBTs in reverse series.In this paper,a novel discrete branch mixture SSCB(DBM-SSCB)is proposed,bidirectional current only flows through one IGBT that has the obvious conduction losses advantage at the same voltage and current level.Only one energy-absorbing component is shared by two discrete branches can guarantee optimal costs and volume.By calculation,the proposed DBM-SSCB can reduce the conduction loss about 30.4%in 10 k V MVDC system,while retaining other advantages of the mixture device SSCB,such as without introducing additional thyristors,charging power supply and the ability to actively interrupt bidirectional fault currents.The blocking principles and designing guidelines are presented in detail,the feasibility is verified by 500 V-18 A simulation results and scale-down experiment,the engineering calculation and simulation of 10 k V-1 k A prototype is completed and compared with other DCCBs.Experimental results and comparative analysis show that the proposed DBM-SSCB has both lower losses and significant performance advantages thus has a good engineering application prospect.展开更多
Marine risers play a key role in the deep and ultra-deep water oil and gas production. The vortex-induced vibration （VIV） of marine risers constitutes an important problem in deep water oil exploration and productio...Marine risers play a key role in the deep and ultra-deep water oil and gas production. The vortex-induced vibration （VIV） of marine risers constitutes an important problem in deep water oil exploration and production. VIV will result in high rates of structural failure of marine riser due to fatigue damage accumulation and diminishes the riser fatigue life. In-service monitoring or full scale testing is essential to improve our understanding of V1V response and enhance our ability to predict fatigue damage. One ma- rine riser fatigue acoustic telemetry scheme is proposed and an engineering prototype machine has been developed to monitor deep and ultra-deep water risers＇ fatigue and failure that can diminish the riser fatigue life and lead to economic losses and eco-catastrophe. Many breakthroughs and innovation have been achieved in the process of developing an engineering prototype machine. Sea trials were done on the 6th generation deep-water drilling platform HYSY-981 in the South China Sea. The inclination monitoring results show that the marine riser fatigue acoustic telemetry scheme is feasible and reliable and the engineering prototype machine meets the design criterion and can match the requirements of deep and ultra-deep water riser fatigue monitoring. The rich experience and field data gained in the sea trial which provide much technical support for optimization in the engineering prototype machine in the future.展开更多
Railway power system is an inseparable part of the power system,therefore,the intelligent architecture of the railway power system should also be focused on.The unique power supply characteristics of the railway power...Railway power system is an inseparable part of the power system,therefore,the intelligent architecture of the railway power system should also be focused on.The unique power supply characteristics of the railway power system are analyzed and integrated railway smart grid architecture based on energy routers is proposed.Importantly,three corresponding resilient mode control methods are suggested for the proposed architecture.In the fourth section,a simulation model corresponding to the resilient control mode is built and the simulation results prove the feasibility of the proposed control mode.Equally,for the novel network-connected backbone router(NCBR),a 1000 kVA,27.5/10 kV NCBR engineering prototype is used to prove its effectiveness in practical applications.Finally,a differentiation analysis is given,followed by conclusions regarding the traditional power system and proposed system.展开更多
基金supported in part by the National Key Research and Development Program of China under Grant 2023YFB2405905in part by The Institute of Electrical Engineering,CAS under Grant E155610301 and E155610201。
文摘Solid state circuit breakers(SSCBs)based on fullcontrolled devices such as IGBT and based on half-controlled devices such as thyristor have their respective advantages.The mixture device solid state circuit breaker(M-SSCB)combines the advantages together and can achieve lower loss,high efficiency,active and reliable blocking at the same time.However,the conduction loss will increase significantly when the topology expanding to a bidirectional topology because the bidirectional line commutation switch(LCS)structure composed of two groups of IGBTs in reverse series.In this paper,a novel discrete branch mixture SSCB(DBM-SSCB)is proposed,bidirectional current only flows through one IGBT that has the obvious conduction losses advantage at the same voltage and current level.Only one energy-absorbing component is shared by two discrete branches can guarantee optimal costs and volume.By calculation,the proposed DBM-SSCB can reduce the conduction loss about 30.4%in 10 k V MVDC system,while retaining other advantages of the mixture device SSCB,such as without introducing additional thyristors,charging power supply and the ability to actively interrupt bidirectional fault currents.The blocking principles and designing guidelines are presented in detail,the feasibility is verified by 500 V-18 A simulation results and scale-down experiment,the engineering calculation and simulation of 10 k V-1 k A prototype is completed and compared with other DCCBs.Experimental results and comparative analysis show that the proposed DBM-SSCB has both lower losses and significant performance advantages thus has a good engineering application prospect.
基金supported in part by the National Science and Technology Major Project of China (2011ZX 05026-001-06)the National Natural Science Foundation of China (51249005 60972153)
文摘Marine risers play a key role in the deep and ultra-deep water oil and gas production. The vortex-induced vibration （VIV） of marine risers constitutes an important problem in deep water oil exploration and production. VIV will result in high rates of structural failure of marine riser due to fatigue damage accumulation and diminishes the riser fatigue life. In-service monitoring or full scale testing is essential to improve our understanding of V1V response and enhance our ability to predict fatigue damage. One ma- rine riser fatigue acoustic telemetry scheme is proposed and an engineering prototype machine has been developed to monitor deep and ultra-deep water risers＇ fatigue and failure that can diminish the riser fatigue life and lead to economic losses and eco-catastrophe. Many breakthroughs and innovation have been achieved in the process of developing an engineering prototype machine. Sea trials were done on the 6th generation deep-water drilling platform HYSY-981 in the South China Sea. The inclination monitoring results show that the marine riser fatigue acoustic telemetry scheme is feasible and reliable and the engineering prototype machine meets the design criterion and can match the requirements of deep and ultra-deep water riser fatigue monitoring. The rich experience and field data gained in the sea trial which provide much technical support for optimization in the engineering prototype machine in the future.
基金Supported by the Zhuhai City Industry-University-Research Project(ZH22017001200019PWC).
文摘Railway power system is an inseparable part of the power system,therefore,the intelligent architecture of the railway power system should also be focused on.The unique power supply characteristics of the railway power system are analyzed and integrated railway smart grid architecture based on energy routers is proposed.Importantly,three corresponding resilient mode control methods are suggested for the proposed architecture.In the fourth section,a simulation model corresponding to the resilient control mode is built and the simulation results prove the feasibility of the proposed control mode.Equally,for the novel network-connected backbone router(NCBR),a 1000 kVA,27.5/10 kV NCBR engineering prototype is used to prove its effectiveness in practical applications.Finally,a differentiation analysis is given,followed by conclusions regarding the traditional power system and proposed system.
