This paper reports a new application of permanent magnet actuator for vacuum contactors.A novel permanent magnet(PM) actuator to drive a vacuum contactor with intrinsically safe and low supply voltage is proposed.PM i...This paper reports a new application of permanent magnet actuator for vacuum contactors.A novel permanent magnet(PM) actuator to drive a vacuum contactor with intrinsically safe and low supply voltage is proposed.PM is mounted on the static iron of the contactor to enhance its holding force and reliability.While only one coil is used to break the vacuum contactor,two series coils are deployed to yield a high magnetomotive force to realize the making operation.The electrical circuit equation,mechanical equation and magnetic field are all coupled in the simulation.A prototype is manufactured and tested to validate and showcase the performance of the contactor which is equipped with the proposed PM actuator.展开更多
A study on the joint channel and symbol estimation issue is provided for two hop relay networks which employ the amplify-and-forward(AF)relaying approach.The encoding scheme at the source node introduces the time-doma...A study on the joint channel and symbol estimation issue is provided for two hop relay networks which employ the amplify-and-forward(AF)relaying approach.The encoding scheme at the source node introduces the time-domain spreading with a time-varying linear constellation precoding.Then,a set of amplifying factors matrices is utilized by the relays to amplify and forward the received data to the destination.The received signal at the destination can be construe ted as a fourth-order tensor model,which is referred to as the nested parallel factor(PARAFAC)model.And then,we present a novel Levenberg-Marquardt(LM)algorithm based on this tensor model.The proposed method does not require complex signal processing at the relay,which effectively reduces the burden of relay.As a semi-blind method,which does not require the pilot signal,the proposed receiver can jointly recover the channels and information symbols.Moreover,the proposed semi-blind receiver is robust as it can work in different wireless channel scenarios.Simulations are conducted to demonstrate the efficiency of the proposed semi-blind approach.展开更多
基金jointly supported by the National Natural Science Foundation of China (Grant No. 50907007)the Specialized Research Fund for the Doctoral Program of Higher Education (Grant No. 20090092120041)+1 种基金the Natural Science Foundation of Jiangsu Province (Grant No. BK2010197)the Key Projects in the Changzhou Science & Technology Pillar Program (Grant No. CE20110024)
文摘This paper reports a new application of permanent magnet actuator for vacuum contactors.A novel permanent magnet(PM) actuator to drive a vacuum contactor with intrinsically safe and low supply voltage is proposed.PM is mounted on the static iron of the contactor to enhance its holding force and reliability.While only one coil is used to break the vacuum contactor,two series coils are deployed to yield a high magnetomotive force to realize the making operation.The electrical circuit equation,mechanical equation and magnetic field are all coupled in the simulation.A prototype is manufactured and tested to validate and showcase the performance of the contactor which is equipped with the proposed PM actuator.
基金the National Natural Science Foundation of China(Nos.61601414 and 61701448)the National Key Research and Development Program of China(No.2016YFB0502001)the Fundamental Research Fund for the Central Universities(Nos.2018CUCTJ082 and CUC18A007)。
文摘A study on the joint channel and symbol estimation issue is provided for two hop relay networks which employ the amplify-and-forward(AF)relaying approach.The encoding scheme at the source node introduces the time-domain spreading with a time-varying linear constellation precoding.Then,a set of amplifying factors matrices is utilized by the relays to amplify and forward the received data to the destination.The received signal at the destination can be construe ted as a fourth-order tensor model,which is referred to as the nested parallel factor(PARAFAC)model.And then,we present a novel Levenberg-Marquardt(LM)algorithm based on this tensor model.The proposed method does not require complex signal processing at the relay,which effectively reduces the burden of relay.As a semi-blind method,which does not require the pilot signal,the proposed receiver can jointly recover the channels and information symbols.Moreover,the proposed semi-blind receiver is robust as it can work in different wireless channel scenarios.Simulations are conducted to demonstrate the efficiency of the proposed semi-blind approach.
