基于地面电场变化的输电线路弧垂监测技术

本文设计了一种基于地面电场变化的输电线路弧垂监测技术,该技术通过输电线路下地面场强的计算可以反演出线路的弧垂大小。技术首先考虑电场测量数据受外界环境因素和测量条件的影响,采用RBF神经网络与一般神经网络相结合的方式建立导线原始测量数据的测量数据修正模型,使修正后的测量数据逼近理想条件下的数据。其次采用本文提出的测量数据修正技术,对场强测量数据进行修正,从而得到输电线路下地面场强的精确值。再次,基于三维输电导线电场计算模型的建立,根据导线下方电场的实时测量数据,在三维电场模型下利用本文设计的基于电场信息的输电线路弧垂反演计算方法得到弧垂值。从次,通过设计基于场强变化的输电线路弧垂监测系统,对弧垂进行监测和报警,保证了输电线路的安全可靠运行。最后,对比某条典型输电导线的测量数据,验证了该算法的有效性。     

感应过电压对输电线路耐雷水平的影响

对于室外架设的输电线路和电线杆等设施,雷电发生时产生的感应过电压所造成的输电线路问题不容忽视,而感应过电压现象的出现还会对输电线路的耐雷水平产生影响,造成长期损伤。文章从计算的角度分析了感应过电压对输电线路耐雷水平的影响情况,分析了感应过电压的影响因素,提出了感应过电压现象的控制办法,旨在提高输电线路的耐雷水平,降低感应过电压的影响。     

750kV输电线路下方感应电的原因分析及防范措施

750kV输电线路下方低电压等级线路及长行导体大量存在,在这些线路上作业时,作业人员常常容易忽视感应电的存在,感应电压电击伤亡事故屡屡发生,严重威胁人身安全。本文介绍了感应电压的产生机理,对交流感应电压进行了分析计算,并提出了在生产中对感应电应采取的措施,为停电检修线路人员避免感应电击提供参考。     

±800kV云广UHVDC输电线路合成电场测试与分析

通过开展不同运行方式下、不同海拔高度处直流输电线路合成电场的实测,分析了直流输电过程中合成电场的特性,总结了运行方式、气象条件和海拔高度对直流输电线路合成电场的影响规律,为特高压技术的发展和环境评估提供了有力的数据支持。     

关于超高压直流输电线路相关的电场环境分析

本文主要分析了超高压直流输电线路相关的电场环境中常见的一些问题和因素,阐述了在当前形势下,加强超高压直流输电线路电场环境研究的重要性。针对目前超高压直流输电线路中电场环境进行研究。笔者通过研究,总结和归纳自身多年的工作和实践经验,提出一些对电场环境多方面研究对策,希望通过本文的分析能帮助相关电场环境研究机构提供一些帮助,能更好的了解超高压直流输电线路相关的电场环境。     

直流高压输电线路对通信线路影响的计算

本文介绍了直流输电电线路对通信线路影响的计算方法，并对有关参数的合理取代进行了讨论。为便于工程计算，本文还推出了适合直流线路结构特点的互感耦合系数简化计算公式，最后分析了防护计算中应注意的问题。     

高压输电线路绝缘子状态检修的研究

随着供电技术装备水平和管理水平的提高,定期检修的不足之处越来越凸显出来,亟需一种新的检修制度来弥补这种不足,这种新的检修方式就是状态检修。本文结合我国输配电线路主设备状态检修的具体实际,介绍了输配线路状态检修的内容,重点介绍了绝缘子的状态检修。     

高压输电线路防雷技术探讨

高压输电线路是电网及电力系统的重要组成部分。高压输电线路易受雷击以导致倒杆断线等事故的发生,不仅造成供电部门的经济损失,甚至危及特殊行业职工的生命安全。本文分析了线路遭受雷击的原因,并就防雷技术进行了综合探讨。     

高压输电线路绝缘子状态检修的研究

高压输电线路和高压输电设备经过长时间的使用,会受到天气变化、机械磨损和电磁振动等因素的影响,容易发生化学反应或者物理反应,严重影响了高压输电线路和高压输电设备的正常运行,因此,只有定期的对高压输电线路和高压输电设备进行检修,才能保障其正常可靠的运行.基于此,本文通过阐述了高压输电线路状态检修的内容和绝缘子状态检修的技术,为以后对高压输电线路绝缘子状态检修的研究提供了理论依据.     

Calculation of capacitance for rectangular coaxial strip transmission line

The field matching method is used to calculate the capacitance of coaxial rectangular strip transmission line. This method is simple, can be used conveniently and the magnitude of error can be effectively controlled.     

A microwatt switched-capacitor voltage doubler-based voltage regulator for ultra-low power energy harvesting systems

This paper presents an SC voltage doubler-based voltage regulator for ultra-low power energy harvesting applications. It produces a stable 1.2-V power supply, using inputs from 0.63 to 1.8 V. External compensation and an on-chip output capacitor ensure good performance even with zero load current and any load capacitance. The regulator tolerates arbitrary input ramp-ups, and is immune to blackout and brownout. A stability analysis for the regulator control loop is presented. The regulator ASIC is implemented in a 180 nm CMOS process. The measured regulator peak power and current efficiency are 63 and 49 %, respectively. The performance has been characterized with load currents from zero to \(100\,\upmu\)A.     

Direct computation of multiconductor transmission line capacitance and charge distribution

The per-unit-length capacitance parameter of multiconductor transmission line (MTL) is commonly extracted with indirect matrix transform method, which is complex and time-consuming. To solve the problem, an improved method to directly compute the MTL capacitance is proposed, which can be applied in the transmission line structure with arbitrary shaped cross-section and arbitrary separate distance. This method imports voltage conversions and matrix operations to simplify the complexity, improves computational efficiency by about 600% with results as accurate as previous method. The novel method presents a clear charge distribution map of MTL, whereas precious method will experience a tortuous process to get charge distribution.     

Novel low-noise 'Fabry-Perot' transmission line oscillator

A low-noise 1.49 GHz oscillator which uses a novel inline transmission line resonator as the positive feedback element is described. A theory which shows how minimum sideband noise can be obtained from such an oscillator is presented, and the degradation of noise performance with circuit parameters is described. Close agreement between the theoretical and experimental results indicates that it is possible to use a simple linear theory in the accurate design of microwave oscillators with minimum sideband noise performance.<>     

低电压高效整流器在能量收集系统中的应用

提出了一种应用在能量收集系统中的低电压CMOS全波整流器。通过引入比较器控制开关,在0.18微米工艺下,最低工作电压可以小于0.7V。由于只使用一个比较器,大大缩减了芯片成本。与相关研究成果比较,设计采用非对称结构,电压转换效率高达93%,系统能量效率达到83%。     

Process and temperature robust voltage multiplier design for RF energy harvesting

Process and temperature invariant voltage multiplier performance has been examined. The analytical predictions of ripple voltage and frequency response are in good agreement with ADS simulation results. In addition, a threshold voltage compensation scheme is investigated to improve the output voltage sensitivity against process variations and temperature fluctuation. The threshold voltage compensation technique effectively reduces the temperature and process variability on the voltage multiplier performance.     

An improved approximation to the microstrip line capacitance

A new empirical formula is presented for the normalised capacitance of microstrip lines. The formula uses a single equation to represent the microstrip line capacitance over the useful range of the aspect ratio. The maximum error of the new formula is contained within 0.8 percent and the relative root-mean-square error is contained within 0.55 percent. The new formula can be easily implemented in computeraided design and analysis as well as in hand calculations using pocket calculators.     

A low power RFID based energy harvesting temperature resilient CMOS-only reference voltage

In this work a low power consumption reference voltage in commercial 40 nm technology is proposed. It adopts a new approach to produce a temperature invariant reference voltage for outdoor RFID applications. To do so, the positive temperature coefficient (TC) of the produced output voltage of a Dickson charge pump is used to cancel out the negative temperature coefficient of the threshold voltage (V_th) of CMOS devices. The result is, according to the post-layout Cadence simulation, a 1.224 V reference voltage with a TC of 60 ppm°C⁻¹ in the temperature range of −10 ^°C to 125 ^°C. The circuit consumes 7 nW with an active area of 0.00033 mm².     

Inversion MOS capacitance extraction for high-leakage dielectricsusing a transmission line equivalent circuit

Accurate measurement of MOS transistor inversion capacitance with a physical silicon dioxide thickness less than 20 Å requires correction for the direct tunneling leakage. This work presents a capacitance model and extraction based on the application of a lossy transmission line model to the MOS transistor. This approach properly accounts for the leakage current distribution along the channel and produces a gate length dependent correction factor for the measured capacitance that overcomes discrepancies produced through use of previously reported discrete element based models. An extraction technique is presented to determine the oxide's tunneling and channel resistance of the transmission line equivalent circuit. This model is confirmed by producing consistent C_0x measurements for several different gate lengths with physical silicon dioxide thickness of 9, 12, and 18 Å     

Joint optimization of energy harvesting and information transmission for trapped user

Wireless Networks - Energy harvesting technology can solve the problem of users’ energy consumption in disaster areas. When disasters occur, some users are trapped and unable to recharge and...