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小电感无刷直流电动机三相H桥无位置传感器控制方法 被引量:12
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作者 石坚 李铁才 +1 位作者 王孝伟 安芳 《中国电机工程学报》 EI CSCD 北大核心 2014年第12期1905-1911,共7页
传统无刷直流电动机的六拍控制采用Y型绕组连接方式,将三相绕组中的两个导通相串联进行供电;其无传感器控制所需的位置信息通过检测未导通相的反电动势过零点得到。绕组串联连接使每一相仅利用母线电压的一半产生电流;同时Y型绕组结构... 传统无刷直流电动机的六拍控制采用Y型绕组连接方式,将三相绕组中的两个导通相串联进行供电;其无传感器控制所需的位置信息通过检测未导通相的反电动势过零点得到。绕组串联连接使每一相仅利用母线电压的一半产生电流;同时Y型绕组结构使未导通相受到中性点电压的影响造成位置信号检测精度降低。该文将三相H桥结构应用于无刷直流电动机的无位置传感器控制,使三相绕组中参与导通的两相并联进行供电,同时使未导通相切出电路以进行反电动势过零点检测。绕组并联连接使每一相利用全部母线电压产生电流,电压利用率得到提高;同时未导通相完全切出电路使位置信号检测精度提高。对三相H桥无刷直流电动机无位置传感器控制方法进行了数学推导和分析,并在一台小电感样机上进行了实验,实验结果显示,该4对极样机可以在20 000 r/min的转速下实现无位置传感器控制。 展开更多
关键词 无刷直流电动机 六拍控制 三相H桥 无位置 传感器 小电感
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考虑小电感区电感变化量的开关磁阻电机开关角优化方法 被引量:11
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作者 曲兵妮 宋世潮 +1 位作者 宋建成 田德翔 《电机与控制学报》 EI CSCD 北大核心 2019年第2期87-93,共7页
开关磁阻电机(switched reluctance motor,SRM)电磁特性具有高度非线性的特点,采用传统的开关角优化方法很难取得理想的控制效果。以三相12/8极SRM为研究对象,采用有限元方法计算了样机的电磁特性,分析了小电感区的非线性特点,建立了电... 开关磁阻电机(switched reluctance motor,SRM)电磁特性具有高度非线性的特点,采用传统的开关角优化方法很难取得理想的控制效果。以三相12/8极SRM为研究对象,采用有限元方法计算了样机的电磁特性,分析了小电感区的非线性特点,建立了电机小电感区内的非线性数学模型,推导了最优开通角的解析式,根据开通角解析式与电机运行时的磁链变化规律,得出了最优关断角解析式,实现了不同转速下开通角与关断角的自适应调节。实验结果表明:改进的开关角优化方法简单有效,提高了系统运行效率和带载能力。 展开更多
关键词 开关磁阻电机 小电感 开通角 关断角
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真空断路器开断小电感电流下多次复燃现象的介质恢复过程分析 被引量:5
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作者 王枫 王仲奕 +1 位作者 郝萌萌 刘志远 《高电压技术》 EI CAS CSCD 北大核心 2018年第6期2019-2026,共8页
真空断路器开断小电感电流产生的多次复燃过电压和介质恢复强度密切相关。因此需建立真空断路器切小感性电流负载的介质恢复微观参数模型,依据此模型得到负载电路参数对真空断路器切小感性电流复燃现象的影响规律。该研究建立了小电感... 真空断路器开断小电感电流产生的多次复燃过电压和介质恢复强度密切相关。因此需建立真空断路器切小感性电流负载的介质恢复微观参数模型,依据此模型得到负载电路参数对真空断路器切小感性电流复燃现象的影响规律。该研究建立了小电感电流真空开断过程的介质恢复鞘层发展模型,得到了介质恢复过程的鞘层发展速度、触头间隙中的电场强度、离子浓度和离子速度等微观参数。以临界击穿场强作为击穿判据,得到了负载电路参数对真空断路器切小感性电流复燃现象的影响规律:负载电容或电感越大,鞘层发展速度变慢,在阴极端产生的最大电场强度越小,因此复燃发生的危险越小,过电压变小;负载端等效电阻的增大会使高频电流幅值减小,从而开断电流减小,鞘层发展速度变慢,最大电场强度降低,因此复燃击穿次数减少。 展开更多
关键词 真空断路器 小电感电流 多次复燃过电压 介质恢复 鞘层
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解决高压无感电阻小电感和高电位梯度矛盾的新方法
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作者 黄东海 黄跃明 《上海电力学院学报》 CAS 1999年第1期20-23,共4页
提出了一种在圆柱形绝缘支架上开槽的特殊绝缘结构来解决高压无感电阻中存在的小尺寸、小电感要求的小匝间距和高电位梯度矛盾的新方法,介绍了利用这种方法实际制作的几种高压无感电阻,并将这些电阻应用于高压大电流快速放电回路中分... 提出了一种在圆柱形绝缘支架上开槽的特殊绝缘结构来解决高压无感电阻中存在的小尺寸、小电感要求的小匝间距和高电位梯度矛盾的新方法,介绍了利用这种方法实际制作的几种高压无感电阻,并将这些电阻应用于高压大电流快速放电回路中分别作为波头、吸能、高压测量电阻,实际应用结果表明:在以空气为绝缘介质及波形为2.5/μs冲击电压作用下,这些电阻的电位梯度最高已达10.5kv/cm,高压测量系统的响应时间小于0.1μs. 展开更多
关键词 高压无感电阻 新方法 绝缘结构 小电感 高电位梯度
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抑制高速电机电流谐波的LC滤波电路设计 被引量:11
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作者 李立毅 谭广军 +1 位作者 刘家曦 寇宝泉 《微电机》 北大核心 2013年第7期38-44,共7页
小电感绕组电机有利于提高定子电流的动态响应速度,然而此特性对电机控制系统还会带来诸多不利影响,诸如产生较高的电流总谐波畸变率(THD),增加绕组铜损和铁芯损耗,同时还会产生较大的转矩脉动和噪声。本文采取了三相LC滤波电路的方法... 小电感绕组电机有利于提高定子电流的动态响应速度,然而此特性对电机控制系统还会带来诸多不利影响,诸如产生较高的电流总谐波畸变率(THD),增加绕组铜损和铁芯损耗,同时还会产生较大的转矩脉动和噪声。本文采取了三相LC滤波电路的方法来减小高速小电感永磁同步电机的定子电流谐波。首先,建立了采用LC滤波电路的永磁同步电机的数学模型。其次,通过对采用LC滤波电路的永磁同步电机系统幅频特性进行分析,给出了用于减小定子电流谐波的LC滤波电路参数的设计原则。同时又分别从三相PWM逆变器所允许输出的最大电流和最大电压的方面考虑,给出了LC滤波参数的取值范围。最后,本文分别给出了仿真和实物实验的结果,验证了本文所提出方法的有效性。 展开更多
关键词 永磁同步电机 小电感电机 LC滤波电路 总谐波畸变率 频域分析
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基于电流型斩波控制器的盘式无铁心永磁同步电机控制方法 被引量:5
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作者 王晓光 王晓远 傅涛 《中国电机工程学报》 EI CSCD 北大核心 2015年第9期2310-2317,共8页
盘式无铁心永磁同步电机具有过载能力强、无定子齿槽、反电势为正弦波等优点,但是由于电机具有绕组电感很小的特点,采用传统电压型逆变器驱动方式的控制效果并不理想。该文针对此类电机的特点,提出了一种新型的控制策略:在逆变桥前端加... 盘式无铁心永磁同步电机具有过载能力强、无定子齿槽、反电势为正弦波等优点,但是由于电机具有绕组电感很小的特点,采用传统电压型逆变器驱动方式的控制效果并不理想。该文针对此类电机的特点,提出了一种新型的控制策略:在逆变桥前端加入电流型斩波电路,根据角度传感器反馈的转子角度值,结合提出的电流控制算法来实时调整定子绕组电流,从而实现电机的转矩控制。并对其工作原理进行了系统的理论分析。仿真和实验结果证实了控制方法的有效性,解决了因电枢电感小而导致定子电流不连续的问题。 展开更多
关键词 盘式无铁心 小电感 电流斩波电路 电流控制算法
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用于毛细管快放电装置中的新型高压无感电阻 被引量:1
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作者 黄东海 肖登明 《高电压技术》 EI CAS CSCD 北大核心 2005年第10期41-43,共3页
为解决常用高压无感电阻中存在的小电感和高电位梯度难于同时满足的矛盾,提出和分析了一种在圆柱形绝缘支架上开槽的新型绝缘结构及其原理,介绍了所制作的高压无感电阻在高压大电流毛细管快放电装置中作高压测量、波头、吸能电阻的应用... 为解决常用高压无感电阻中存在的小电感和高电位梯度难于同时满足的矛盾,提出和分析了一种在圆柱形绝缘支架上开槽的新型绝缘结构及其原理,介绍了所制作的高压无感电阻在高压大电流毛细管快放电装置中作高压测量、波头、吸能电阻的应用。新型绝缘结构能通过增加开槽深度来增加高压无感电阻相邻匝间的沿面放电距离,但不会增大相邻匝间的间距,故可有效提高高压无感电阻的电位梯度而不会增加电阻的残余电感,它特别适用于以空气作介质的高压无感电阻或纵向空间受限制的场所。 展开更多
关键词 高压无感电阻 新型绝缘结构 毛细管快放电装置 高电位梯度 小电感
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基于Buck Chopper电路多相多重拓扑结构的直流稳流电源的设计与实现 被引量:4
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作者 党怀东 王有云 康英 《电气传动自动化》 2009年第2期26-30,共5页
针对离子加速器系统中小电感磁铁对高精度、低纹波电源的严格要求,提出了一种基于Buck Chopper电路多相多重化的拓扑结构,对其工作原理进行了深入分析,并完成了装置设计,最后对调试结果做了分析说明。
关键词 小电感 高精度 低纹波 多相多重
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简单电磁振荡和电磁波演示器
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作者 姜峻婷 《技术物理教学》 1998年第2期28-28,共1页
在电磁振荡与电磁波的教学中,力图通过纯理论性的剖析,精深透辟地把电磁振荡与电磁波的传送与接收阐述清楚,是很难的.但若用直观的演示,再配以画龙点睛的说明,就会使学生对电磁振荡与电磁波有深刻的理解与认识.本文介绍一套价格... 在电磁振荡与电磁波的教学中,力图通过纯理论性的剖析,精深透辟地把电磁振荡与电磁波的传送与接收阐述清楚,是很难的.但若用直观的演示,再配以画龙点睛的说明,就会使学生对电磁振荡与电磁波有深刻的理解与认识.本文介绍一套价格便宜、取材方便、制作容易的电磁振荡... 展开更多
关键词 电磁振荡 电磁波 高频变压器 演示器 小电感 音频振荡器 场效应管 音频电压 振荡频率 音频调制
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Non-inverting buck-boost DC-DC converter based on constant inductor current control
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作者 Yao Suyi Jiang Jianguo 《Journal of Southeast University(English Edition)》 EI CAS 2021年第2期171-176,共6页
The hysteresis control combined with PWM control non-inverting buck-boost was proposed to improve the light load efficiency and power density.The constant inductor current control(CICC)was established to mitigate the ... The hysteresis control combined with PWM control non-inverting buck-boost was proposed to improve the light load efficiency and power density.The constant inductor current control(CICC)was established to mitigate the dependence on the external components and device variation and make smooth transition between hysteresis control loop and pulse width modulation(PWM)control loop.The small signal model was deduced for the buck and boost operation mode.The inductor current slope control(ICSC)was proposed to implement the automatic mode transition between buck and boost mode in one switching cycle.The results show that the converter prototype has good dynamic response capability,achieving 94%efficiency and 95%peak efficiency at full 10 A load current. 展开更多
关键词 four switch buck-boost converter inductor current slope control constant inductor current control small signal model
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Minimum sensing cell measurement in network domain based on PIR sensor array
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作者 KANG Xin-chen YANG Wei +2 位作者 CAO Zhi-bin LU Yun DENG Li-qi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第1期16-20,共5页
To reasearch on the infrared target perception by pyroelectric infrared (PIR) sensor in network domain measurement,a closed sensing network domain composed of eight-PIR-sensor array is proposed for the minimum sensing... To reasearch on the infrared target perception by pyroelectric infrared (PIR) sensor in network domain measurement,a closed sensing network domain composed of eight-PIR-sensor array is proposed for the minimum sensing cell measurement in network domain and to realize the moving target perception and trajectory prediction. Moreover,the feasibility and accuracy of the proposed method are verified through experiments. The experimental results demonstrate that the maximum error between the real trajectory and the predicted trajectory of the minimum sensing cell measurement method is 0.64 m,which can achieve infrared target perception and moving trajectory prediction. 展开更多
关键词 pyroelectric infrared (PIR) sensor minimum sensing cell trajectory prediction
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A Study on an Airgap Control System in a Rotary-Small-Scaled Linear Induction Motor for Railway Vehicles
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作者 C.B. Park B.S. Lee 《Journal of Energy and Power Engineering》 2011年第12期1193-1198,共6页
In general, it is important to operate the; airgap length uniformly for improving the system efficiency independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LI... In general, it is important to operate the; airgap length uniformly for improving the system efficiency independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LIM). And it is possible to operate the LIM propulsion system efficiently without a change of the LIM capacity through the airgap length control on the sloped rail. So, in this research, the authors introduce an airgap control system to control the airgap length which depends on the flatness of the secondary reaction plate when the LIM is operated, and design a rotary small-scaled LIM and its airgap control system before manufacturing the real system. Then, the authors analyze some characteristics of the LIM (thrust and normal force, input current, efficiency and power factor), and through the LIM control modeling, the authors finally analyze an effect of the airgap-length control of the LIM by the airgap control system. 展开更多
关键词 Airgap control system linear induction motor PROPULSION railway vehicles.
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Role of transient receptor potential vanilloid subetype 1 in the increase of thermal pain threshold by moxibustion 被引量:8
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作者 Li Jiejun Jiang Jingfeng 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第5期583-587,共5页
OBTECTIVE:To explore the role of transient receptor potential vaniiloid subetype 1(TRPV1) in the increase of the thermal pain threshold by moxibustion.METHODS:Forty Kunming mice(20 ± 2) g were randomized into con... OBTECTIVE:To explore the role of transient receptor potential vaniiloid subetype 1(TRPV1) in the increase of the thermal pain threshold by moxibustion.METHODS:Forty Kunming mice(20 ± 2) g were randomized into control group,capsaicin group,capsazepine group,moxibustion group and moxibustion + capsazepine(MC) group with 8 mice in each,and 16 C57BL/6 wild-type mice(18 ± 2) g were randomized into wild-type(WT) control group and WT moxibustion group with 8 mice in each,and 14 TRPV1 knockout mice(18 ± 2) g were randomized into knockout(KO) control group and KO moxibustion group with 7 in each.Each mouse in the capsaicin group was subcutaneously injected with the amount of 0.1 mL/10 g into L5 and L6 spinal cords;each mouse in the capsazepine group was intraperitoneally injected with the amount of0.1 mL/10 g.Similarly,each mouse in the moxibustion group was given a suspended moxibustion with specially-made moxa-stick for 20 min on L5 and L6 spinal cords.Each mouse in MC group was intraperitoneally injected with the amount of 0.1 mL/10 g first,then after 15 min was given a suspended moxibustion for 20 min on L5 and L6 spinal cords.Each mouse in WT moxibustion group and KO moxibustion group was given a suspended moxibustion with specially-made moxa-stick for 20 min on L5 and L6 spinal cords.The control group,WT control group and KO control group were of no treatment in any way.After all treatments were completed,the digital-display measurement instrument for thermal pain was used to measure the threshold of thermal pain in each group respectively.RESULTS:Compared with the control group,the thresholds of thermal pain in the moxibustion group and MC group were significantly increased(P <0.01);no significant changes in the thresholds in the capsaicin group and the capsazepine group(P > 0.05);compared with moxibustion group,he threshold of thermal in MC group was obviously decreased(P < 0.01).Compared with WT control group,the threshold of thermal pain in WT moxibustion group was significantly increased(P <0.01);compared with KO control group,no changes in the threshold in KO moxibustion group(P > 0.05).CONCLUSION:TRPV1 participated in the process of increasing the threshold of thermal pain by stimulating L5 and L6 of mice spinal cord with burning mosa-stick. 展开更多
关键词 Moxa stick moxibustion Pain threshold Heat stimulation Transient Receptor Potential Vanilloid subetype 1
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Unmodified and positively charged gold nanoparticles for sensitive colorimetric detection of folate receptor via terminal protection of small molecule-linked ss DNA
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作者 Min Wang Fangzhen Li +4 位作者 Bingying Jiang Junqiang Xu Shuo Li Yun Xiang Ruo Yuan 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第6期770-775,共6页
The detection of protein/small molecule interactions plays important roles in drug discovery and protein/metabolite interactions in biology. In this work, by coupling the terminal protection of small molecule-linked s... The detection of protein/small molecule interactions plays important roles in drug discovery and protein/metabolite interactions in biology. In this work, by coupling the terminal protection of small molecule-linked ss DNA strategy with the unmodified and positively charged gold nanoparticle((+)Au NP) nanoprobes, we have developed a sensitive and simple colorimetric sensor for the detection of folate receptor, a highly expressed protein in many kinds of malignant tumors. The target folate receptor binds the folate moieties of the folate-linked ss DNA through high affinity interactions and protects the protein-bound ss DNA from digestion by exonuclease I. The protected ss DNA thus adsorbs the((+)Au NP) through electrostatic interactions, leading to a red-to-blue color change of the sensing solution for sensitive colorimetric detection of folate receptor at the sub-nanomolar level. Besides, this colorimetric sensor shows high selectivity toward folate receptor against other control proteins. The developed sensor avoids the modification/conjugation of the Au NP nanoprobes and the involvement of any expensive instruments for signal transduction in protein detection. Featured with these obvious advantages, the colorimetric sensor strategy demonstrated herein can be easily expanded for sensitive and convenient detection of various protein/small molecule interactions. 展开更多
关键词 COLORIMETRY positively charged gold nanoparticles SENSOR terminal protection folate receptor
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