The existing wireless power transfer(WPT)systems for gastrointestinal capsule robot have the prob-lems of small coupling coefficient and low power transmission efficiency(PTE).The reasons are due to the long distance ...The existing wireless power transfer(WPT)systems for gastrointestinal capsule robot have the prob-lems of small coupling coefficient and low power transmission efficiency(PTE).The reasons are due to the long distance between the transmitting coil and the receiving coil and the large difference in size.A new type of WPT system is designed,which uses three sets of small coil pairs to form a power supply unit(PSU),and utilizes multiple PSUs to form a multi-coil WPT system.Compared with single-coil system,the multi-coil system can achieve higher power utilization by switching between PSUs,instead of opening all PSUs.ANSYS Maxwell is used to perform finite element modeling on the PSU,analyzing the characteristics of the transmitting magnetic field.The results of the experiment show that when the distance between the small coil pairs in the PSU is 180mm,the magnetic field has relatively good uniformity,and the magnetic strength change relative to the center point is less than 5%.The average received power of the system is greater than 800mW,and the PTE is up to 5.1%.展开更多
针对经颅磁刺激(transcranial magnetic stimulation,TMS)应用存在的定位精度及动态调节受限问题,基于时间干涉磁刺激(temporal interference transcranial magnetic stimulation,TI-TMS)理论和多通道TMS设计思路,开发了一种由15个磁芯...针对经颅磁刺激(transcranial magnetic stimulation,TMS)应用存在的定位精度及动态调节受限问题,基于时间干涉磁刺激(temporal interference transcranial magnetic stimulation,TI-TMS)理论和多通道TMS设计思路,开发了一种由15个磁芯线圈组成的头盔式阵列。通过COMSOL建模分析线圈电流方向、电流比对聚焦区域动态调控的影响规律,结果显示:1)双线圈电流方向(同向或反向)都能产生TI包络,但会影响包络电场相位;2)通过调节线圈电流比,可精准控制聚焦区域空间偏移;3)头盔式阵列支持多靶点联合刺激。采用五层球模型和真实头模型的验证性实验发现,通过电子控制线圈阵列激磁模式,可生成多个目标靶点的精确聚焦和快速切换,对实现多靶点TI-TMS技术,最终开发居家神经调控系统提供了理论依据,具有实际应用潜力。展开更多
凭借兼具无功功率支撑(reactive power support,RPS)与接地故障调控(grounding fault control,GFC)能力,复合装置得到广泛关注。但是,现有复合装置存在容量过高、需要额外附加供电装置的问题。针对上述问题,基于充分利用既有站内资源的...凭借兼具无功功率支撑(reactive power support,RPS)与接地故障调控(grounding fault control,GFC)能力,复合装置得到广泛关注。但是,现有复合装置存在容量过高、需要额外附加供电装置的问题。针对上述问题,基于充分利用既有站内资源的思想,提出一种基于站内资源的新型无功功率支撑与接地故障调控复合装置(RPS and GFC composite device,RGCD)。首先,介绍RGCD的拓扑结构与运行原理,RGCD由站内电容器、站内消弧线圈和多功能变流器(multi-functional converter,MC)构成,当电网正常运行时,站内电容器补偿负荷所需的大部分无功功率,剩余部分由MC进行补偿;当发生单相接地故障时,站内电容器进行无功补偿,站内消弧线圈和MC进行接地故障调控,在不同运行模式下均实现了MC容量降低。其次,分析接地故障调控期间的能量流动机理,并提出基于直流侧电压稳定的P-Q两相消弧方法,实现免供电装置下RGCD的稳定运行。最后,通过仿真验证了所提拓扑及运行原理的有效性与可行性。展开更多
基金the National Natural Science Founda-tion of China(Nos.61673271 and 81971767)the Shang-hai Research Project(Nos.19441910600,19441913800 and 19142203800)the Project of Institute of Medical Robotics,Shanghai Jiao Tong University(No.IMR2018KY05)。
文摘The existing wireless power transfer(WPT)systems for gastrointestinal capsule robot have the prob-lems of small coupling coefficient and low power transmission efficiency(PTE).The reasons are due to the long distance between the transmitting coil and the receiving coil and the large difference in size.A new type of WPT system is designed,which uses three sets of small coil pairs to form a power supply unit(PSU),and utilizes multiple PSUs to form a multi-coil WPT system.Compared with single-coil system,the multi-coil system can achieve higher power utilization by switching between PSUs,instead of opening all PSUs.ANSYS Maxwell is used to perform finite element modeling on the PSU,analyzing the characteristics of the transmitting magnetic field.The results of the experiment show that when the distance between the small coil pairs in the PSU is 180mm,the magnetic field has relatively good uniformity,and the magnetic strength change relative to the center point is less than 5%.The average received power of the system is greater than 800mW,and the PTE is up to 5.1%.
文摘针对经颅磁刺激(transcranial magnetic stimulation,TMS)应用存在的定位精度及动态调节受限问题,基于时间干涉磁刺激(temporal interference transcranial magnetic stimulation,TI-TMS)理论和多通道TMS设计思路,开发了一种由15个磁芯线圈组成的头盔式阵列。通过COMSOL建模分析线圈电流方向、电流比对聚焦区域动态调控的影响规律,结果显示:1)双线圈电流方向(同向或反向)都能产生TI包络,但会影响包络电场相位;2)通过调节线圈电流比,可精准控制聚焦区域空间偏移;3)头盔式阵列支持多靶点联合刺激。采用五层球模型和真实头模型的验证性实验发现,通过电子控制线圈阵列激磁模式,可生成多个目标靶点的精确聚焦和快速切换,对实现多靶点TI-TMS技术,最终开发居家神经调控系统提供了理论依据,具有实际应用潜力。
文摘凭借兼具无功功率支撑(reactive power support,RPS)与接地故障调控(grounding fault control,GFC)能力,复合装置得到广泛关注。但是,现有复合装置存在容量过高、需要额外附加供电装置的问题。针对上述问题,基于充分利用既有站内资源的思想,提出一种基于站内资源的新型无功功率支撑与接地故障调控复合装置(RPS and GFC composite device,RGCD)。首先,介绍RGCD的拓扑结构与运行原理,RGCD由站内电容器、站内消弧线圈和多功能变流器(multi-functional converter,MC)构成,当电网正常运行时,站内电容器补偿负荷所需的大部分无功功率,剩余部分由MC进行补偿;当发生单相接地故障时,站内电容器进行无功补偿,站内消弧线圈和MC进行接地故障调控,在不同运行模式下均实现了MC容量降低。其次,分析接地故障调控期间的能量流动机理,并提出基于直流侧电压稳定的P-Q两相消弧方法,实现免供电装置下RGCD的稳定运行。最后,通过仿真验证了所提拓扑及运行原理的有效性与可行性。
