Real-time onboard health monitoring systems are critical for the railway industry to maintain high service quality and operational safety.However,the issue with power supplies for monitoring sensors persists,especiall...Real-time onboard health monitoring systems are critical for the railway industry to maintain high service quality and operational safety.However,the issue with power supplies for monitoring sensors persists,especially for freight trains that lack onboard power.Here,we propose a hybrid piezoelectric-triboelectric rotary generator(HPT-RG)for energy harvesting and vehicle speed sensing.The HPT-RG incorporates a rotational self-adaptive technique that softens the equivalent stiffness,enabling the piezoelectric non-resonant beam to surpass resonance limitations in a low-frequency region.The experiments demonstrate the feasibility of using the HPT-RG as an energy harvesting module to collect the rotational energy of the freight rail transport and power the wireless temperature sensors.To allow multiple monitoring in confined spaces on trains,a triboelectric sensing module is added to the HPT-RG to sense the operation speed and mileage of vehicles.Furthermore,the generator exhibits favorable mechanical durability under more than 600 h of official testing on the train bogie axle.The proposed HPT-RG is essential for creating a truly self-powered,maintenance-free,and zero-carbon onboard wireless monitoring system on freight railways.展开更多
The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered ...The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered property. However, a TENG cannot easily work at low wind speeds due to the limitation of the high frictional resistance structure. In this paper, a TENG-based breezeactivated wind speed sensor(BAWS) with an ultra-low frictional resistance is proposed. The key drive unit of the BAWS is a Savonius-like vertical axis wind turbine, which is fabricated by arrayed airfoil profile blades with excellent flow field characteristics. Here a wind turbine plays dual roles in driving the electromagnetic generator below it to supply energy and lead the TENG above it to sense the wind force. Compared to a classical turbine with a wind cup, the designed turbine has a low resistance torque. The synergistic effect of the drive unit with low-resistance and triboelectric materials with low viscosity allows the BAWS to be activated even at a wind speed of 2.9 m/s. The sensitivities of the voltage frequency and current amplitude of the TENG are used to reflect the electrical property of the BAWS. The measured values are 0.291 Hz/(m·s-1) and 0.221 μA/(m·s-1),which reflects the good sensitivity of the BAWS. Moreover, the linearity of the BAWS reaches up to 0.991, which shows an accurate output for the wind speed. In addition, the device is equipped with a combined electromagnetic-solar unit as the sole power source to meet the sensor’s all-weather operation requirements. This work expands the application prospects of selfpowered sensing technology in the field of disaster warning.展开更多
This paper mainly studies Weather Stations part of the wind power station. The use of wind energy in practice is carried out using the facilities of the wind in which the kinetic energy of the windscreen flow is conve...This paper mainly studies Weather Stations part of the wind power station. The use of wind energy in practice is carried out using the facilities of the wind in which the kinetic energy of the windscreen flow is converted into mechanical energy wind speed, then electrical energy alternator. The effective operation of the wind turbine is dependent on the direction of the wind. Speed air density, which in turn depends on the temperature and humidity. Thus, the speed of the wind worked effectively in its composition must include the weather. Meteorological station also performs the role of prevention. When the sharp wind speed or increase wind speed above the maximum value, it sends a signal to the lock assembly wind to prevent wind turbine technology from damage. The work of the meteorological stations design as part of the Wind Energy Station is considered. The complex technical devices are used for its implementation. A set of technical means used to its implementation and designed system consists of a temperature, humidity, wind speed, wind direction and rain gauge sensors that are connected to PIC16f876A microcontroller.展开更多
风速和风向是影响高速列车运行安全的重要因素,对高铁沿线的大风风速和风向进行有效预测有助于及时地对列车运行状况进行评估和预警。目前高铁大风领域的研究主要集中在风速的预测,尚未考虑风速风向的联合预测。基于深度循环神经网络—...风速和风向是影响高速列车运行安全的重要因素,对高铁沿线的大风风速和风向进行有效预测有助于及时地对列车运行状况进行评估和预警。目前高铁大风领域的研究主要集中在风速的预测,尚未考虑风速风向的联合预测。基于深度循环神经网络—长短记忆(LSTM)模型,提出独立预测法、分量预测法和多变量预测法等3种风速与风向联合预测方法,并利用兰新高铁大风监测实测数据对沿线多个基站的短期风速和风向进行同步联合预测。首先,通过归一化预处理原始风向和风速序列,并运用控制变量法确定最优时间步长和模型参数。其次,采用BPTT(Backpropagation Through Time)和Adam算法进行迭代训练,并结合早停法控制收敛,得到优化后的网络结构。最后,利用训练好的LSTM网络,采用3种方法对风速和风向进行联合预测。4个基站的实验结果表明,优化后的LSTM模型可以有效提取风速风向时间序列的长期依赖特征,结合联合预测方法能够实现对风速和风向的高精度同步预测;3种联合预测方法都能在较小范围内准确预测风速和风向,除5520基站外,风速预测误差在15%以内,风向预测误差在20%以内,其中多变量预测法表现出最优的整体预测精度,独立预测法次之。本研究为风速风向的联合预测提供了新的视角,对保障高铁列车运行的安全性具有参考价值。展开更多
Utilizing shaft-speed information to analyse vibration signals is an important method for fault diagnosis and condition monitoring of rotating machineries,especially for those running at variable speeds.However,in man...Utilizing shaft-speed information to analyse vibration signals is an important method for fault diagnosis and condition monitoring of rotating machineries,especially for those running at variable speeds.However,in many cases,shaft-speed information is not always available,for a variety of reasons.Fortunately,in most of the measurements,the shaft-speed information is embedded in the vibration response in many different forms,such as in the format of the fundamental shaft-rotation-frequency response and its harmonics,and the gear-meshing-frequency response and its harmonics,etc.Proper signal processing can be used to extract the shaft instantaneous speed from the measured vibration responses.In existing instantaneous shaft-speed-identification methods,a narrow-bandpass filtering technique is used explicitly or implicitly.In a complex gearbox system,such as that used in a wind turbine,the gear-meshing-response component could be modulated by many other shaft speeds,due to the configuration of the gearbox or due to the existence of component damage.As a result,it is very difficult to isolate a single vibration-response component for instantaneous shaft-speed detection.In this paper,an innovative approach is presented.The instantaneous shaft speed is extracted based on maxima tracking from the vibration-response spectrogram.A numerical integration scheme is employed to obtain the shaft instantaneous phase.Digital-domain synchronous resampling is then applied to the vibration data by using the instantaneous phase information.Due to the nature of noise suppression in the numerical integration,the accuracy of synchronous sampling is greatly improved.This proposed approach demonstrates the feasibility and engineering applicability through a controlled laboratory test case and two field wind-turbine cases.More detailed results and conclusions of this research are presented at the end of this paper.展开更多
The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Tribo...The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Triboelectric nanogenerators(TENGs)offer significant advantages for self-powered sensing due to their sensitivity to environmental changes.Therefore,the present study has introduced a planetary gear structure that is known for its efficient transmission and smooth operation characteristics.A planetary gear-driven triboelectric speed sensor(PGTS)has also been designed.The structural optimization was performed by combining finite element analysis with experimental results.At a speed of 120 rpm,the open-circuit voltage and short-circuit current could reach 10 V and 0.2μA,respectively.Also,a peak power of 1.51μW was achieved at a load resistance of 30 MΩ.A high-precision revolution speed sensing algorithm was further developed for a real-time and accurate perception of the vehicle speed.The research results demonstrated that the PTGS was successfully integrated into the small-scale indoor tire-road testing platform,achieving a sensing accuracy of up to 99% in measuring the revolution speed.Furthermore,real vehicle tests were conducted using a Volkswagen Passat,and the fitting goodness-of-fit for the vehicle speed perception still reached 99%,with a minimum realtime fitting accuracy of 80.25%.Finally,a high-performance vehicle emergency monitoring system based on the vehicle slip rate level was proposed for monitoring abnormal vehicle behavior,which could promote a safety upgrade of the autonomous driving technology.展开更多
As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and...As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and efficient self-powered mine wind speed monitoring and alarm system(SLW-MAS)is proposed based on triboelectric nanogenerator(TENG).The SLW-MAS,featuring a centrifugal structure design,facilitates hierarchical control of the TENG module,thereby enabling differential responses to wind speeds.When the wind speed is lower than 1.5 m/s,the TENG module is maintained in a horizontal working state under the action of the centrifugal mechanism and produces a high voltage output;the switch circuit is selected through experiments,which makes it meet the alarm delay of 2 s and avoids the problem of inaccurate alarm caused by unstable airflow.This work provides the feasibility for the construction of an underground distributed Internet of Things monitoring and alarm system.展开更多
The intend of this paper is to give a description of the realization of a low-cost wind turbine emulator （WTE） with open source technology from graze required for the condition monitoring to diagnose rotor and stato...The intend of this paper is to give a description of the realization of a low-cost wind turbine emulator （WTE） with open source technology from graze required for the condition monitoring to diagnose rotor and stator faults in a wind turbine generator （WTG）. The WTE comprises of a 2.5 kW DC motor coupled with a 1 kW squirrel-cage induction machine. This paper provides a detailed overview of the hardware and software used along with the WTE control strategies such as MPPT and pitch control. The emulator reproduces dynamic characteristics both under step variations and arbitrary variation in the wind speed of a typical wind turbine （WT） of a wind energy conversion system （WECS）. The usefulness of the setup has been benchmarked with previously verified WT test rigs made at the University of Manchester and Durham University in UK. Considering the fact that the rotor blades and electric subassemblies direct drive WTs are most susceptible to damage in practice, generator winding faults and rotor unbalance have been introduced and investigated using the terminal voltage and generated current. This wind turbine emulator （WTE） can be reconfigured or analyzed for condition monitoring without the need for real WTs.展开更多
针对现阶段气象遥感卫星在台风监测过程中存在的重访周期较长、难以实现对台风全过程连续监测等突出问题,引入星载全球导航卫星系统反射测量(Global Navigation Satellite System Reflectometry,GNSS-R)技术的旋风全球导航卫星系统(Cycl...针对现阶段气象遥感卫星在台风监测过程中存在的重访周期较长、难以实现对台风全过程连续监测等突出问题,引入星载全球导航卫星系统反射测量(Global Navigation Satellite System Reflectometry,GNSS-R)技术的旋风全球导航卫星系统(Cyclone Global Navigation Satellite System,CYGNSS)卫星开展台风全过程监测分析.基于CYGNSS的L2风速产品,提出了一种轨迹间异常值剔除法的数据净化策略,通过选择典型台风事件验证了星载CYGNSS具备从台风生成初期至发展各阶段的全过程监测能力和台风结构识别能力.利用2022—2024年CYGNSS风速产品与美国国家海洋和大气管理局(National Oceanic and Atmospheric Administration,NOAA)提供的三大洋台风风速数据进行对比,结果显示,CYGNSS风速相对于NOAA风速的均方根误差(root mean square error,RMSE)为11.98 m/s,相关系数为0.713,表明CYGNSS风速产品在全球尺度台风监测中具有良好的一致性和可靠性.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12302022,12172248,12021002,and 12132010)Tianjin Research Program of Application Foundation and Advanced Technology(Grant No.22JCQNJC00780)+1 种基金the State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures(Grant No.KF2024-09)the IoT Standards and Application Key Laboratory of the Ministry of Industry and Information Technology(Grant No.202306).
文摘Real-time onboard health monitoring systems are critical for the railway industry to maintain high service quality and operational safety.However,the issue with power supplies for monitoring sensors persists,especially for freight trains that lack onboard power.Here,we propose a hybrid piezoelectric-triboelectric rotary generator(HPT-RG)for energy harvesting and vehicle speed sensing.The HPT-RG incorporates a rotational self-adaptive technique that softens the equivalent stiffness,enabling the piezoelectric non-resonant beam to surpass resonance limitations in a low-frequency region.The experiments demonstrate the feasibility of using the HPT-RG as an energy harvesting module to collect the rotational energy of the freight rail transport and power the wireless temperature sensors.To allow multiple monitoring in confined spaces on trains,a triboelectric sensing module is added to the HPT-RG to sense the operation speed and mileage of vehicles.Furthermore,the generator exhibits favorable mechanical durability under more than 600 h of official testing on the train bogie axle.The proposed HPT-RG is essential for creating a truly self-powered,maintenance-free,and zero-carbon onboard wireless monitoring system on freight railways.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51975542, 62101513, and 62171414)Young Academic Leaders Project of North University of China (Grant No. 11045501)。
文摘The early warning and monitoring of gale disasters are very important for the safety of people’s lives and properties. Triboelectric nanogenerators(TENGs) are popular for wind speed sensors due to their self-powered property. However, a TENG cannot easily work at low wind speeds due to the limitation of the high frictional resistance structure. In this paper, a TENG-based breezeactivated wind speed sensor(BAWS) with an ultra-low frictional resistance is proposed. The key drive unit of the BAWS is a Savonius-like vertical axis wind turbine, which is fabricated by arrayed airfoil profile blades with excellent flow field characteristics. Here a wind turbine plays dual roles in driving the electromagnetic generator below it to supply energy and lead the TENG above it to sense the wind force. Compared to a classical turbine with a wind cup, the designed turbine has a low resistance torque. The synergistic effect of the drive unit with low-resistance and triboelectric materials with low viscosity allows the BAWS to be activated even at a wind speed of 2.9 m/s. The sensitivities of the voltage frequency and current amplitude of the TENG are used to reflect the electrical property of the BAWS. The measured values are 0.291 Hz/(m·s-1) and 0.221 μA/(m·s-1),which reflects the good sensitivity of the BAWS. Moreover, the linearity of the BAWS reaches up to 0.991, which shows an accurate output for the wind speed. In addition, the device is equipped with a combined electromagnetic-solar unit as the sole power source to meet the sensor’s all-weather operation requirements. This work expands the application prospects of selfpowered sensing technology in the field of disaster warning.
文摘This paper mainly studies Weather Stations part of the wind power station. The use of wind energy in practice is carried out using the facilities of the wind in which the kinetic energy of the windscreen flow is converted into mechanical energy wind speed, then electrical energy alternator. The effective operation of the wind turbine is dependent on the direction of the wind. Speed air density, which in turn depends on the temperature and humidity. Thus, the speed of the wind worked effectively in its composition must include the weather. Meteorological station also performs the role of prevention. When the sharp wind speed or increase wind speed above the maximum value, it sends a signal to the lock assembly wind to prevent wind turbine technology from damage. The work of the meteorological stations design as part of the Wind Energy Station is considered. The complex technical devices are used for its implementation. A set of technical means used to its implementation and designed system consists of a temperature, humidity, wind speed, wind direction and rain gauge sensors that are connected to PIC16f876A microcontroller.
文摘风速和风向是影响高速列车运行安全的重要因素,对高铁沿线的大风风速和风向进行有效预测有助于及时地对列车运行状况进行评估和预警。目前高铁大风领域的研究主要集中在风速的预测,尚未考虑风速风向的联合预测。基于深度循环神经网络—长短记忆(LSTM)模型,提出独立预测法、分量预测法和多变量预测法等3种风速与风向联合预测方法,并利用兰新高铁大风监测实测数据对沿线多个基站的短期风速和风向进行同步联合预测。首先,通过归一化预处理原始风向和风速序列,并运用控制变量法确定最优时间步长和模型参数。其次,采用BPTT(Backpropagation Through Time)和Adam算法进行迭代训练,并结合早停法控制收敛,得到优化后的网络结构。最后,利用训练好的LSTM网络,采用3种方法对风速和风向进行联合预测。4个基站的实验结果表明,优化后的LSTM模型可以有效提取风速风向时间序列的长期依赖特征,结合联合预测方法能够实现对风速和风向的高精度同步预测;3种联合预测方法都能在较小范围内准确预测风速和风向,除5520基站外,风速预测误差在15%以内,风向预测误差在20%以内,其中多变量预测法表现出最优的整体预测精度,独立预测法次之。本研究为风速风向的联合预测提供了新的视角,对保障高铁列车运行的安全性具有参考价值。
文摘Utilizing shaft-speed information to analyse vibration signals is an important method for fault diagnosis and condition monitoring of rotating machineries,especially for those running at variable speeds.However,in many cases,shaft-speed information is not always available,for a variety of reasons.Fortunately,in most of the measurements,the shaft-speed information is embedded in the vibration response in many different forms,such as in the format of the fundamental shaft-rotation-frequency response and its harmonics,and the gear-meshing-frequency response and its harmonics,etc.Proper signal processing can be used to extract the shaft instantaneous speed from the measured vibration responses.In existing instantaneous shaft-speed-identification methods,a narrow-bandpass filtering technique is used explicitly or implicitly.In a complex gearbox system,such as that used in a wind turbine,the gear-meshing-response component could be modulated by many other shaft speeds,due to the configuration of the gearbox or due to the existence of component damage.As a result,it is very difficult to isolate a single vibration-response component for instantaneous shaft-speed detection.In this paper,an innovative approach is presented.The instantaneous shaft speed is extracted based on maxima tracking from the vibration-response spectrogram.A numerical integration scheme is employed to obtain the shaft instantaneous phase.Digital-domain synchronous resampling is then applied to the vibration data by using the instantaneous phase information.Due to the nature of noise suppression in the numerical integration,the accuracy of synchronous sampling is greatly improved.This proposed approach demonstrates the feasibility and engineering applicability through a controlled laboratory test case and two field wind-turbine cases.More detailed results and conclusions of this research are presented at the end of this paper.
基金supported by the National Key R&D Program of China(No.2023YFB2604600)the International Cooperation Project of Science and Technology Commission of Shanghai Municipality(No.22210710700)+1 种基金the National Natural Science Foundation of China(No.52278455)the Shuguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.21SG24).
文摘The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Triboelectric nanogenerators(TENGs)offer significant advantages for self-powered sensing due to their sensitivity to environmental changes.Therefore,the present study has introduced a planetary gear structure that is known for its efficient transmission and smooth operation characteristics.A planetary gear-driven triboelectric speed sensor(PGTS)has also been designed.The structural optimization was performed by combining finite element analysis with experimental results.At a speed of 120 rpm,the open-circuit voltage and short-circuit current could reach 10 V and 0.2μA,respectively.Also,a peak power of 1.51μW was achieved at a load resistance of 30 MΩ.A high-precision revolution speed sensing algorithm was further developed for a real-time and accurate perception of the vehicle speed.The research results demonstrated that the PTGS was successfully integrated into the small-scale indoor tire-road testing platform,achieving a sensing accuracy of up to 99% in measuring the revolution speed.Furthermore,real vehicle tests were conducted using a Volkswagen Passat,and the fitting goodness-of-fit for the vehicle speed perception still reached 99%,with a minimum realtime fitting accuracy of 80.25%.Finally,a high-performance vehicle emergency monitoring system based on the vehicle slip rate level was proposed for monitoring abnormal vehicle behavior,which could promote a safety upgrade of the autonomous driving technology.
基金support from the National Key Research and Development Program of China(No.2021YFA1201601)the Beijing Natural Science Foundation(Nos.L244004 and 3244038)the Macao university of Science and Technology Faculty Research Grants(General Research Grants,GRFs)(No.FRG-24-084-FIE).
文摘As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and efficient self-powered mine wind speed monitoring and alarm system(SLW-MAS)is proposed based on triboelectric nanogenerator(TENG).The SLW-MAS,featuring a centrifugal structure design,facilitates hierarchical control of the TENG module,thereby enabling differential responses to wind speeds.When the wind speed is lower than 1.5 m/s,the TENG module is maintained in a horizontal working state under the action of the centrifugal mechanism and produces a high voltage output;the switch circuit is selected through experiments,which makes it meet the alarm delay of 2 s and avoids the problem of inaccurate alarm caused by unstable airflow.This work provides the feasibility for the construction of an underground distributed Internet of Things monitoring and alarm system.
文摘The intend of this paper is to give a description of the realization of a low-cost wind turbine emulator （WTE） with open source technology from graze required for the condition monitoring to diagnose rotor and stator faults in a wind turbine generator （WTG）. The WTE comprises of a 2.5 kW DC motor coupled with a 1 kW squirrel-cage induction machine. This paper provides a detailed overview of the hardware and software used along with the WTE control strategies such as MPPT and pitch control. The emulator reproduces dynamic characteristics both under step variations and arbitrary variation in the wind speed of a typical wind turbine （WT） of a wind energy conversion system （WECS）. The usefulness of the setup has been benchmarked with previously verified WT test rigs made at the University of Manchester and Durham University in UK. Considering the fact that the rotor blades and electric subassemblies direct drive WTs are most susceptible to damage in practice, generator winding faults and rotor unbalance have been introduced and investigated using the terminal voltage and generated current. This wind turbine emulator （WTE） can be reconfigured or analyzed for condition monitoring without the need for real WTs.
文摘针对现阶段气象遥感卫星在台风监测过程中存在的重访周期较长、难以实现对台风全过程连续监测等突出问题,引入星载全球导航卫星系统反射测量(Global Navigation Satellite System Reflectometry,GNSS-R)技术的旋风全球导航卫星系统(Cyclone Global Navigation Satellite System,CYGNSS)卫星开展台风全过程监测分析.基于CYGNSS的L2风速产品,提出了一种轨迹间异常值剔除法的数据净化策略,通过选择典型台风事件验证了星载CYGNSS具备从台风生成初期至发展各阶段的全过程监测能力和台风结构识别能力.利用2022—2024年CYGNSS风速产品与美国国家海洋和大气管理局(National Oceanic and Atmospheric Administration,NOAA)提供的三大洋台风风速数据进行对比,结果显示,CYGNSS风速相对于NOAA风速的均方根误差(root mean square error,RMSE)为11.98 m/s,相关系数为0.713,表明CYGNSS风速产品在全球尺度台风监测中具有良好的一致性和可靠性.
