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自动刺络采血拔罐装置结构设计与控制
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作者 吴泓睿 吴限 +2 位作者 李昀蔚 李悦 胡冰山 《建模与仿真》 2024年第5期5312-5320,共9页
本文针对现有刺络拔罐器无法控制拔罐时长、刺络时间点和吸纳刺络产生的污血问题,以STM32F103C8T6单片机为核心控制元件,控制微型真空泵对拔罐罐体内部抽真空和控制推拉式电磁阀带动刺络针进行刺络,同时使用毛细管吸纳污血,设计了一种... 本文针对现有刺络拔罐器无法控制拔罐时长、刺络时间点和吸纳刺络产生的污血问题,以STM32F103C8T6单片机为核心控制元件,控制微型真空泵对拔罐罐体内部抽真空和控制推拉式电磁阀带动刺络针进行刺络,同时使用毛细管吸纳污血,设计了一种自动刺络采血拔罐装置,并进行了可用性实验。实验结果表明,该装置能有效处理刺络产生的污血,拔罐时长、拔罐罐体内部负压大小和刺络时间点的精度均达到预期设计和技术指标。该装置显著降低刺络拔罐疗法的操作难度,能够拓宽刺络拔罐疗法的应用空间,并为刺络拔罐的相关研究提供了新的思路。 展开更多
关键词 刺络 拔罐 控制
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Overview of control,integration and energy management of microgrids 被引量:35
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作者 yunwei li Farzam NEJABATKHAH 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2014年第3期212-222,共11页
Microgrids are being developed as a building block for future smart grid system.Key issues for the control and operation of microgrid include integration technologies and energy management schemes.This paper presents ... Microgrids are being developed as a building block for future smart grid system.Key issues for the control and operation of microgrid include integration technologies and energy management schemes.This paper presents an overview of grid integration and energy management strategies of microgrids.It covers a review of power electronics interface topologies for different types of distributed generation(DG)units in a microgrid,a discussion of energy management strategies,as well as the DG interfacing converter control schemes.Considering the intermittent nature of many renewable energy based DG units,the ancillary services of DGs using the available interfacing converter rating are also discussed in the paper. 展开更多
关键词 Distributed generation Energy management schemes Harmonic compensation Interfacing converters MICROGRID Power quality Unbalance voltage compensation
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Evaluation of High Step-up Power Conversion Systems for Large-capacity Photovoltaic Generation Integrated into Medium Voltage DC Grids
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作者 Shilei Lu Kai Sun +2 位作者 Haixu Shi yunwei li Guoen Cao 《Chinese Journal of Electrical Engineering》 CSCD 2021年第4期3-14,共12页
With the increase of dc based renewable energy generation and dc loads,the medium voltage dc(MVDC)distribution network is becoming a promising option for more efficient system integration.In particular,large-capacity ... With the increase of dc based renewable energy generation and dc loads,the medium voltage dc(MVDC)distribution network is becoming a promising option for more efficient system integration.In particular,large-capacity photovoltaic(PV)-based power generation is growing rapidly,and a corresponding power conversion system is critical to integrate these large PV systems into MVDC power grid.Different from traditional ac grid-connected converters,the converter system for dc grid interfaced PV system requires large-capacity dc conversion over a wide range of ultra-high voltage step-up ratios.This is an important issue,yet received limited research so far.In this paper,a thorough study of dc-dc conversion system for a medium-voltage dc grid-connected PV system is conducted.The required structural features for such a conversion system are first discussed.Based on these features,the conversion system is classified into four categories by series-parallel connection scheme of power modules.Then two existing conversion system configurations as well as a proposed solution are compared in terms of input/output performance,conversion efficiency,modulation method,control complexity,power density,reliability,and hardware cost.In-depth analysis is carried out to select the most suitable conversion systems in various application scenarios. 展开更多
关键词 Photovoltaic generation dc-dc conversion medium voltage dc grid large-capacity ultra-high voltage transfer ratio
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Derivation of Multilevel Voltage Source Converter Topologies for Medium Voltage Drives
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作者 yunwei li Zhongyi Quan 《Chinese Journal of Electrical Engineering》 CSCD 2017年第2期24-31,共8页
Multilevel voltage source converters(MLVSCs)have been widely applied in the medium voltage drive(MVD)industry.The performance of a MVD system is strongly dependent on the utilized topology.As of today,many interesting... Multilevel voltage source converters(MLVSCs)have been widely applied in the medium voltage drive(MVD)industry.The performance of a MVD system is strongly dependent on the utilized topology.As of today,many interesting topologies have been proposed and evaluated in literature.In addition to proposing new topologies,another important research topic is the MLVSC topology derivation.In this paper,two topology derivation principles,i.e.horizontal conformation principle and vertical conformation principle,are proposed from the standpoint of modularity.In both principles,a MLVSC topology can be considered as a certain combination of one base switching cell and several module switching cells.With the proposed principle,the derived topology will naturally have modularity,which is favorable in practical applications.In addition,voltage level extension based on cascaded H-bridge building blocks(HBBBs)is also introduced.The challenging issues faced by the emerging topologies for MVD applications are also discussed.It is hoped that this paper can provide a new perspective on the MLVSC topology derivation and inspire new topologies in the future. 展开更多
关键词 Multilevel converters voltage source converters TOPOLOGIES medium voltage drives
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