智能手机的飞速发展和智能手机APP的不断更新对当今社会的各个方面都产生了深远的影响。与此同时,智能手机APP也逐渐被引入课堂教学中,为学生提供了自主学习的机会,也使物理实验教学模式发生了巨大的改变,成了广大教育者关注的热点。利...智能手机的飞速发展和智能手机APP的不断更新对当今社会的各个方面都产生了深远的影响。与此同时,智能手机APP也逐渐被引入课堂教学中,为学生提供了自主学习的机会,也使物理实验教学模式发生了巨大的改变,成了广大教育者关注的热点。利用Vernier Video Physics软件和Vernier Graphical Analysis软件,再结合平抛运动实验仪,对小钢球的运动轨迹进行逐帧追踪定位,得到小钢球做平抛运动的y-x图像、x-t图像、y-t图像和v_(y)-t图像,再对图像进行相应函数拟合,经过数据分析,得到小钢球做平抛运动在水平方向和竖直方向的运动特点。利用智能手机APP辅助高中物理实验教学可以激发学生的学习兴趣,帮助学生理解物理概念和规律,使学生积极主动地参与到实验中来,培养他们的动手能力,提升他们的实验素养。展开更多
This paper proposes a new consequent-pole permanent magnet vernier machine(CPMVM),which can be regarded as a combination of two conventional CPMVM with opposite polarities.Based on the simplified axial magnetic circui...This paper proposes a new consequent-pole permanent magnet vernier machine(CPMVM),which can be regarded as a combination of two conventional CPMVM with opposite polarities.Based on the simplified axial magnetic circuit model,it is verified that the proposed CPMVM can reduce the unipolar leakage flux.In order to reduce the torque ripple of machine and improve the output torque of machine,the flux barrier is placed on the rotor of the proposed machine.Then,the parameters of the proposed CPMVM are optimized and determined.Moreover,the electromagnetic performance,including no-load air-gap flux density,average torque and torque ripple,flux linkage,back-electromotive force,cogging torque,average torque,torque ripple,power factor and loss,is compared with conventional surface-mounted permanent magnet vernier machine(SPMVM)and CPMVM.Finally,it is demonstrated that proposed CPMVM with flux barrier can effectively reduce the unipolar leakage flux and greatly reduce the torque ripple of machine.Also,compared with the SPMVM,the proposed CPMVM with flux barrier saves more than 45%of the permanent magnet material without reducing output torque.展开更多
将智能手机的APP功能应用于中学物理教学实践,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了小车的匀加速直线运动和匀减速直线运动,得到了运动的轨迹图以及小车运动的x-t、v-t图象.实际生活...将智能手机的APP功能应用于中学物理教学实践,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了小车的匀加速直线运动和匀减速直线运动,得到了运动的轨迹图以及小车运动的x-t、v-t图象.实际生活中最常见的投篮过程中篮球的运动,作为二维斜抛运动的特例,得到了篮球运动的轨迹图以及两个方向上的x-t、v-t图象.通过对图象的分析提高学生对这些运动的深刻认识,解决了传统教学中学生很难理解为什么将曲线运动分解为两个直线运动的问题,使得教学更具可视化.将现代化教学设备应用到课堂教学,提高学生处理、分析图象的能力,体现了核心素养对高中物理教学的基本要求.展开更多
随着信息技术的不断发展,智能手机App为实验研究和教学拓展了新思路。利用Vernier Video Physics软件及其配套的数据分析软件研究小圆块的平抛运动和斜抛运动的运动规律,既可突破传统教学方法的局限,又能提高学生处理、分析图象的能力,...随着信息技术的不断发展,智能手机App为实验研究和教学拓展了新思路。利用Vernier Video Physics软件及其配套的数据分析软件研究小圆块的平抛运动和斜抛运动的运动规律,既可突破传统教学方法的局限,又能提高学生处理、分析图象的能力,从而凸显高中物理教学培养核心素养的基本要求。展开更多
Offshore wind energy is an important part of clean energy,and the adoption of wind energy to generate electricity will contribute to the implementation of the carbon peaking and carbon neutrality goals.The combination...Offshore wind energy is an important part of clean energy,and the adoption of wind energy to generate electricity will contribute to the implementation of the carbon peaking and carbon neutrality goals.The combination of the fractional frequency transmission system(FFTS) and the direct-drive wind turbine generator will be beneficial to the development of the offshore wind power industry.The use of fractional frequency in FFTS is beneficial to the transmission of electrical energy,but it will also lead to an increase in the volume and weight of the generator,which is unfavorable for wind power generation.Improving the torque density of the generator can effectively reduce the volume of the generators.The vernier permanent magnet machine(VPM) operates on the magnetic flux modulation principle and has the merits of high torque density.In the field of electric machines,the vernier machine based on the principle of magnetic flux modulation has been proved its feasibility to reduce the volume and weight.However,in the field of low-speed direct-drive machines for high-power fractional frequency power generation,there are still few related researches.Therefore,this paper studies the application of magnetic flux modulation in fractional frequency and high-power direct-drive wind turbine generators,mainly analyzes the influence of different pole ratios and different pole pairs on the generator,and draws some conclusions to provide reference for the design of wind turbine generators.展开更多
This paper proposes a V-shaped permanent magnet vernier(V-PMV)motor for potential applications in direct drive system.By designing suitable pole slot ratio and adopting the V-shaped PM topology and dummy slots in roto...This paper proposes a V-shaped permanent magnet vernier(V-PMV)motor for potential applications in direct drive system.By designing suitable pole slot ratio and adopting the V-shaped PM topology and dummy slots in rotor,the flux leakage can be avoided effectively.Meanwhile,the high-order harmonics with large amplitude in the airgap magnetic field are fully utilized and served as the effective working harmonics,which aim at enhancing the output torque and reducing the torque ripple.Moreover,to extensively explore the performance advantages of the V-PMV motor,a multi-objective optimization study is carried out.And,the electromagnetic performances of the V-PMV motors are analyzed and compared in detail.Finally,a prototype machine is built and tested.Both theoretical analysis and experimental results verify the validity of the motor and multi-objective optimization design approach.展开更多
随着科技的不断发展,将信息技术与物理实验课堂相融合,已经成为教师培养学生科学素养和信息素养的一种重要手段.采用控制变量法探究影响单摆周期的因素,利用Vernier Video Physics视频分析软件对小钢球的运动轨迹进行逐帧追踪定位,得到...随着科技的不断发展,将信息技术与物理实验课堂相融合,已经成为教师培养学生科学素养和信息素养的一种重要手段.采用控制变量法探究影响单摆周期的因素,利用Vernier Video Physics视频分析软件对小钢球的运动轨迹进行逐帧追踪定位,得到小钢球做单摆运动的x-t图像和v-t图像,通过数据分析,得到单摆周期与摆球质量、振幅和摆长之间的定量关系.实验器材取自日常生活,成本低廉,为学生课后自主探究创造了条件.对培养学生的创新意识、发展学生的自主学习能力和独立研究能力有重要的意义,有利于学生从被动学习转变为自主、合作、探究的学习范式.展开更多
将智能手机APP功能应用到中学物理教学实践中,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了实际生活中最常见的投篮过程中篮球的运动.作为二维斜抛运动的特例,得到了篮球运动的轨迹图以及两...将智能手机APP功能应用到中学物理教学实践中,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了实际生活中最常见的投篮过程中篮球的运动.作为二维斜抛运动的特例,得到了篮球运动的轨迹图以及两个方向上的x-t和v-t图像.通过对图像的分析提高学生对这些运动的深刻认识,解决了传统教学中学生很难理解将曲线运动分解到两个方向的直线运动,使得教学更具可视化.将现代化教学设备应用到课堂教学,提高学生处理、分析图像的能力,体现了核心素养对高中物理教学的基本要求.展开更多
信息技术与物理教学的融合是当今物理教育的热点。利用手机Vernier Video Physics App研究自由落体运动和单摆运动,对小球进行逐帧追踪定位,实时创建出小球做自由落体运动及单摆运动的相关运动图像并进行数据拟合,简便、高效、直观地揭...信息技术与物理教学的融合是当今物理教育的热点。利用手机Vernier Video Physics App研究自由落体运动和单摆运动,对小球进行逐帧追踪定位,实时创建出小球做自由落体运动及单摆运动的相关运动图像并进行数据拟合,简便、高效、直观地揭示物体运动规律,促进学生对物理概念和规律的理解,为教师辅助传统实验教学及学生课外自主探究提供了有力工具。展开更多
A fault-tolerant permanent-magnet vernier(FT-PMV)machine incorporates the merits of high fault-tolerant capability and high torque density.In this paper,a remedial phase-angle control(RPAC)strategy is proposed for a f...A fault-tolerant permanent-magnet vernier(FT-PMV)machine incorporates the merits of high fault-tolerant capability and high torque density.In this paper,a remedial phase-angle control(RPAC)strategy is proposed for a five-phase FT-PMV machine with short-circuit fault.Firstly,the proposed strategy can reduce the amount of unknown quantities by structuring the phase-angles of the normal phases.It can simplify the calculation of the remedial currents.Then,in order to obtain the desired torque,only the amplitudes of the remedial currents need to be calculated.Based on the principle of instantaneous electrical input power and mechanical output power balance condition,the real components are used to maintain the torque capability,while the reactive components are limited zero to minimize the torque ripple.Both simulations and experiments are presented to verify the proposed RPAC strategy.展开更多
A novel dynamic optical add-drop multiplexer(OADM) scheme using tunable sampled fiber Bragg gratings(SFBG) by Vernier effect is firstly proposed. In this scheme, broad wavelength tuning range is achieved by only sligh...A novel dynamic optical add-drop multiplexer(OADM) scheme using tunable sampled fiber Bragg gratings(SFBG) by Vernier effect is firstly proposed. In this scheme, broad wavelength tuning range is achieved by only slightly adjusting the SFBG, the wavelength tuning of OADM will be faster than traditional dynamic OADM.展开更多
This paperpresents a single-stage Vernier Time-to-Digital Converter (VTDC) that utilizes the dynamic-logic phase detector. The zero dead-zone characteristic of this phase detector allows for the single-stage VTDC to d...This paperpresents a single-stage Vernier Time-to-Digital Converter (VTDC) that utilizes the dynamic-logic phase detector. The zero dead-zone characteristic of this phase detector allows for the single-stage VTDC to deliver sub-gate delay time resolution. The single-stage VTDC has been designed in 0.13μm CMOS technology. The simulation results demonstrate a linear input-output characteristic for input dynamic range from 0 to 1.6ns with a time resolution of 25ps.展开更多
In this paper,a high precision vernier delay line(VDL) TDC(Time-to-Digital Convertor) in an actel flash-based Field-Programmable-Gate-Arrays A3PE1500 is implemented,achieving a resolution of 16.4-ps root mean square v...In this paper,a high precision vernier delay line(VDL) TDC(Time-to-Digital Convertor) in an actel flash-based Field-Programmable-Gate-Arrays A3PE1500 is implemented,achieving a resolution of 16.4-ps root mean square value or 42-ps averaged bin size.The TDC has a dead time of about 200 ns while the dynamic range is 655.36 μs.The double delay lines method is employed to cut the dead time in half to improve its performance.As the bin size of the TDC is dependent on temperature,a compensation algorithm is adopted as temperature drift correction,and the TDC shows satisfying performance in a temperature range from –5℃ to +55℃.展开更多
Recognizing the position of moving objects, facilities or important equipments has been regarded as a hot issue in the future environment which needs ubiquitous characteristics. Furthermore, it is indispensably needed...Recognizing the position of moving objects, facilities or important equipments has been regarded as a hot issue in the future environment which needs ubiquitous characteristics. Furthermore, it is indispensably needed to acquire location data in order to realize an infrastructure of sensor network system. Namely, distance data are the preliminary information to complete localization of a moving object in local area. Even though there have been several researches on this topic, there are however still much amount of problems in getting precisely exact distance data. Out of them, the research on using TOF (Time-of-flight) is very few as well as could be thought of as a cutting-edge technique. Moreover, it is very difficult to get minutely RF signal's TOF for getting short distance data; that is, very complicated signal processing skills are requested for realizing it. In this paper, we present a new methodology of RF short ranging technique based on vernier effect through using of heterogeneous operating clocks.展开更多
文摘智能手机的飞速发展和智能手机APP的不断更新对当今社会的各个方面都产生了深远的影响。与此同时,智能手机APP也逐渐被引入课堂教学中,为学生提供了自主学习的机会,也使物理实验教学模式发生了巨大的改变,成了广大教育者关注的热点。利用Vernier Video Physics软件和Vernier Graphical Analysis软件,再结合平抛运动实验仪,对小钢球的运动轨迹进行逐帧追踪定位,得到小钢球做平抛运动的y-x图像、x-t图像、y-t图像和v_(y)-t图像,再对图像进行相应函数拟合,经过数据分析,得到小钢球做平抛运动在水平方向和竖直方向的运动特点。利用智能手机APP辅助高中物理实验教学可以激发学生的学习兴趣,帮助学生理解物理概念和规律,使学生积极主动地参与到实验中来,培养他们的动手能力,提升他们的实验素养。
基金supported in part by the National Natural Science Foundation of China under Projects 52177044 and 52025073in part by the China Postdoctoral Science Foundation under Project 2019T120395+3 种基金in part by Hong Kong Scholars Program under Project XJ2019031in part by the Natural Science Foundation of Jiangsu Higher Education Institutions under Project 21KJA470004in part by Qing Lan Project of Jiangsu Provincein part by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘This paper proposes a new consequent-pole permanent magnet vernier machine(CPMVM),which can be regarded as a combination of two conventional CPMVM with opposite polarities.Based on the simplified axial magnetic circuit model,it is verified that the proposed CPMVM can reduce the unipolar leakage flux.In order to reduce the torque ripple of machine and improve the output torque of machine,the flux barrier is placed on the rotor of the proposed machine.Then,the parameters of the proposed CPMVM are optimized and determined.Moreover,the electromagnetic performance,including no-load air-gap flux density,average torque and torque ripple,flux linkage,back-electromotive force,cogging torque,average torque,torque ripple,power factor and loss,is compared with conventional surface-mounted permanent magnet vernier machine(SPMVM)and CPMVM.Finally,it is demonstrated that proposed CPMVM with flux barrier can effectively reduce the unipolar leakage flux and greatly reduce the torque ripple of machine.Also,compared with the SPMVM,the proposed CPMVM with flux barrier saves more than 45%of the permanent magnet material without reducing output torque.
文摘将智能手机的APP功能应用于中学物理教学实践,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了小车的匀加速直线运动和匀减速直线运动,得到了运动的轨迹图以及小车运动的x-t、v-t图象.实际生活中最常见的投篮过程中篮球的运动,作为二维斜抛运动的特例,得到了篮球运动的轨迹图以及两个方向上的x-t、v-t图象.通过对图象的分析提高学生对这些运动的深刻认识,解决了传统教学中学生很难理解为什么将曲线运动分解为两个直线运动的问题,使得教学更具可视化.将现代化教学设备应用到课堂教学,提高学生处理、分析图象的能力,体现了核心素养对高中物理教学的基本要求.
基金supported by the Science and Technology Foundation of SGCC (5500-202099509A-0-0-00)“Research on Fractional Frequency Transmission Technology for Largely Enhancing Transmission Capacity and Development of Its Key Devices”。
文摘Offshore wind energy is an important part of clean energy,and the adoption of wind energy to generate electricity will contribute to the implementation of the carbon peaking and carbon neutrality goals.The combination of the fractional frequency transmission system(FFTS) and the direct-drive wind turbine generator will be beneficial to the development of the offshore wind power industry.The use of fractional frequency in FFTS is beneficial to the transmission of electrical energy,but it will also lead to an increase in the volume and weight of the generator,which is unfavorable for wind power generation.Improving the torque density of the generator can effectively reduce the volume of the generators.The vernier permanent magnet machine(VPM) operates on the magnetic flux modulation principle and has the merits of high torque density.In the field of electric machines,the vernier machine based on the principle of magnetic flux modulation has been proved its feasibility to reduce the volume and weight.However,in the field of low-speed direct-drive machines for high-power fractional frequency power generation,there are still few related researches.Therefore,this paper studies the application of magnetic flux modulation in fractional frequency and high-power direct-drive wind turbine generators,mainly analyzes the influence of different pole ratios and different pole pairs on the generator,and draws some conclusions to provide reference for the design of wind turbine generators.
基金supported in part by the Natural Science Foundation of China under Grant 52177046,51991385,51807081 and 51937006in part by the China Postdoctoral Science Foundation under Project 2020T130256 and 2018M642178。
文摘This paper proposes a V-shaped permanent magnet vernier(V-PMV)motor for potential applications in direct drive system.By designing suitable pole slot ratio and adopting the V-shaped PM topology and dummy slots in rotor,the flux leakage can be avoided effectively.Meanwhile,the high-order harmonics with large amplitude in the airgap magnetic field are fully utilized and served as the effective working harmonics,which aim at enhancing the output torque and reducing the torque ripple.Moreover,to extensively explore the performance advantages of the V-PMV motor,a multi-objective optimization study is carried out.And,the electromagnetic performances of the V-PMV motors are analyzed and compared in detail.Finally,a prototype machine is built and tested.Both theoretical analysis and experimental results verify the validity of the motor and multi-objective optimization design approach.
文摘随着科技的不断发展,将信息技术与物理实验课堂相融合,已经成为教师培养学生科学素养和信息素养的一种重要手段.采用控制变量法探究影响单摆周期的因素,利用Vernier Video Physics视频分析软件对小钢球的运动轨迹进行逐帧追踪定位,得到小钢球做单摆运动的x-t图像和v-t图像,通过数据分析,得到单摆周期与摆球质量、振幅和摆长之间的定量关系.实验器材取自日常生活,成本低廉,为学生课后自主探究创造了条件.对培养学生的创新意识、发展学生的自主学习能力和独立研究能力有重要的意义,有利于学生从被动学习转变为自主、合作、探究的学习范式.
文摘将智能手机APP功能应用到中学物理教学实践中,已成为教师激发学生学习兴趣和培养学生动手能力的新途径.利用Vernier Video Physics研究了实际生活中最常见的投篮过程中篮球的运动.作为二维斜抛运动的特例,得到了篮球运动的轨迹图以及两个方向上的x-t和v-t图像.通过对图像的分析提高学生对这些运动的深刻认识,解决了传统教学中学生很难理解将曲线运动分解到两个方向的直线运动,使得教学更具可视化.将现代化教学设备应用到课堂教学,提高学生处理、分析图像的能力,体现了核心素养对高中物理教学的基本要求.
文摘信息技术与物理教学的融合是当今物理教育的热点。利用手机Vernier Video Physics App研究自由落体运动和单摆运动,对小球进行逐帧追踪定位,实时创建出小球做自由落体运动及单摆运动的相关运动图像并进行数据拟合,简便、高效、直观地揭示物体运动规律,促进学生对物理概念和规律的理解,为教师辅助传统实验教学及学生课外自主探究提供了有力工具。
基金This work was supported by the National Natural Science Foundation of China(51422702)by the by the Qing Lan Project,and by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘A fault-tolerant permanent-magnet vernier(FT-PMV)machine incorporates the merits of high fault-tolerant capability and high torque density.In this paper,a remedial phase-angle control(RPAC)strategy is proposed for a five-phase FT-PMV machine with short-circuit fault.Firstly,the proposed strategy can reduce the amount of unknown quantities by structuring the phase-angles of the normal phases.It can simplify the calculation of the remedial currents.Then,in order to obtain the desired torque,only the amplitudes of the remedial currents need to be calculated.Based on the principle of instantaneous electrical input power and mechanical output power balance condition,the real components are used to maintain the torque capability,while the reactive components are limited zero to minimize the torque ripple.Both simulations and experiments are presented to verify the proposed RPAC strategy.
文摘A novel dynamic optical add-drop multiplexer(OADM) scheme using tunable sampled fiber Bragg gratings(SFBG) by Vernier effect is firstly proposed. In this scheme, broad wavelength tuning range is achieved by only slightly adjusting the SFBG, the wavelength tuning of OADM will be faster than traditional dynamic OADM.
文摘This paperpresents a single-stage Vernier Time-to-Digital Converter (VTDC) that utilizes the dynamic-logic phase detector. The zero dead-zone characteristic of this phase detector allows for the single-stage VTDC to deliver sub-gate delay time resolution. The single-stage VTDC has been designed in 0.13μm CMOS technology. The simulation results demonstrate a linear input-output characteristic for input dynamic range from 0 to 1.6ns with a time resolution of 25ps.
基金Supported by State Key Program of National Natural Science of China under Grant No.11079003Fundamental Research Funds for the Central Universities(No.WK2030040023,and WK2030040015)
文摘In this paper,a high precision vernier delay line(VDL) TDC(Time-to-Digital Convertor) in an actel flash-based Field-Programmable-Gate-Arrays A3PE1500 is implemented,achieving a resolution of 16.4-ps root mean square value or 42-ps averaged bin size.The TDC has a dead time of about 200 ns while the dynamic range is 655.36 μs.The double delay lines method is employed to cut the dead time in half to improve its performance.As the bin size of the TDC is dependent on temperature,a compensation algorithm is adopted as temperature drift correction,and the TDC shows satisfying performance in a temperature range from –5℃ to +55℃.
文摘Recognizing the position of moving objects, facilities or important equipments has been regarded as a hot issue in the future environment which needs ubiquitous characteristics. Furthermore, it is indispensably needed to acquire location data in order to realize an infrastructure of sensor network system. Namely, distance data are the preliminary information to complete localization of a moving object in local area. Even though there have been several researches on this topic, there are however still much amount of problems in getting precisely exact distance data. Out of them, the research on using TOF (Time-of-flight) is very few as well as could be thought of as a cutting-edge technique. Moreover, it is very difficult to get minutely RF signal's TOF for getting short distance data; that is, very complicated signal processing skills are requested for realizing it. In this paper, we present a new methodology of RF short ranging technique based on vernier effect through using of heterogeneous operating clocks.
