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为解决新型数字化电能表计量检测与“溯源”问题,通过引入“模拟式计量合并单元”、“计算型模拟标准表”、“数字合成模拟功率源”概念及设备,给出了数字化电能表“标准源比较法”、“标准表比较法”、“综合比较法”三种检测方案及其完整的标准传递/“溯源”系统,合理地把数字式电能表检测与“溯源”纳入到传统电能表标准传递/溯源系统中,使数字化电能计量完全沿用模拟计量系统,简单、科学、经济地解决了数字化电能表检测与“溯源”等技术问题。数字量与模拟量电能计量体系的统一,承继了电能计量标准传递/溯源系统不间断链接性、稳定性、严肃性并具备一定的逻辑性、合理性、严谨性,降低了数字化计量系统风险性。在数字化电能计量过程中去“数字化”是对电能计量技术的一种创新与发展。 相似文献
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针对部分企事业单位供电的特殊性,在市电供给突然断电的情况下,设计出24V、5A恒压源做为后备电源。此电源可以自动切换,不需人工干预,确保后续设备正常工作。经过试验证明完全满足设计要求。 相似文献
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为了更好分析系统的放电特性和工作状态,优化脉冲功率源系统的设计,研制了一套1.2MV重复频率高功率微波驱动电源测试诊断系统。通过研究高电压、大电流测试技术和数据采集、信号处理、故障诊断技术,同时运用虚拟仪器和电磁兼容等技术,探索开发了一套重复频率脉冲电压电流测试诊断系统。结合系统的研制需求,通过分析各种数据采集设备的优缺点,硬件选用了凌华公司的PXI数据采集系统,软件采用LabVIEW,设计开发了重复频率快信号的采集诊断程序,研制出实时诊断系统,并在1.2MV重复频率脉冲电源系统中应用,实现了对重复频率电源关键点电压电流的测试以及数据的诊断、处理和远程在线监测,出现故障时报警、存储数据并自动断电等功能。 相似文献
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半导体激光器(LD)是一种电流注入式电致发光器件,其工作特性和使用寿命主要取决于驱动电流源的性能优劣。本文作者设计了一种用于中、小功率LD的新型电流源,它的工作原理是电压/电流转换、电流放大和电流负反馈。输出电流在0~3A范围内可连续调节,当电流分别为2A和3A时,连续5小时内的电流变化量均小于1mA,相应的电流稳定度分别为5.0×10-4和3.3×10-4。另外,该电源还具有抗击浪涌击穿、断电保护和过流保护等多种功能。与以往的电源相比,该电流源具有原理简单、稳定性好等优点,在教学、科研和生产中有很好的应用前景。 相似文献
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一种高稳定半导体激光器驱动电源的设计与分析 总被引:1,自引:0,他引:1
设计了一种高稳定半导体激光器驱动恒流电源,分析和讨论了集成运放负反馈型恒流源的负载、温度特性以及稳定精度。给出了LD注入电流稳定度的测量结果,LD注入电流稳定度可达10^-6,用稳定的激光器观察了充有约1.3kPa缓冲气体的自然铷的D2吸收谱线。此外,该电源还具有抗击浪涌击穿、断电保护和过流保护等多种功能。 相似文献
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The dynamic characteristics of harvesting energy from mechanical vibration via piezoelectric conversion
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As an alternative power solution for low-power devices, harvesting energy from the ambient mechanical vibration has received increasing research interest in recent years. In this paper we study the transient dynamic characteristics of a piezoelectric energy harvesting system including a piezoelectric energy harvester, a bridge rectifier, and a storage capacitor. To accomplish this, this energy harvesting system is modeled, and the charging process of the storage capacitor is investigated by employing the in-phase assumption The results indicate that the charging voltage across the storage capacitor and the gathered power increase gradually as the charging process proceeds, whereas the charging rate slows down over time as the charging voltage approaches to the peak value of the piezoelectric voltage across the piezoelectric materials. In addition, due to the added electrical damping and the change of the system natural frequency when the charging process is initiated, a sudden drop in the vibration amplitude is observed, which in turn affects the charging rate. However, the vibration amplitude begins to increase as the charging process continues, which is caused by the decrease in the electrical damping (i.e., the decrease in the energy removed from the mechanical vibration). This electromechanical coupling characteristic is also revealed by the variation of the vibration amplitude with the charging voltage. 相似文献
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传统的高功率重复频率脉冲功率源通常以低电压储能、升压、高压脉冲形成线、输出的顺序工作。因而系统至少包括低压储能和高压脉冲形成线两个储能环节,同时高压脉冲形成线的体积随着电压的升高快速增长。针对这些问题,课题组提出了一种高功率重复频率Marx型脉冲功率源小型化研究的设计思路和实现方式,并开展了相关技术研究。主要介绍了课题组在关键技术上取得的重要进展,包括高储能密度的储能/脉冲成形一体化技术、低抖动重复频率气体开关技术、低抖动高能触发技术、紧凑型Marx高压串叠技术等一系列关键技术。同时介绍了课题组研制的几种典型紧凑结构重复频率Marx型脉冲功率装置:同轴结构快Marx发生器、基于薄膜介质线的脉冲功率源、模块化低阻抗紧凑型Marx发生器、20 GW高功率重复频率脉冲驱动源。通过探讨关键技术研究及其发展现状,为未来脉冲功率源小型化研究的发展和应用方向提供参考。 相似文献
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高压脉冲电容器是脉冲功率系统中应用较广的储能器件。根据大容量能库型脉冲装置对充电电源的技术要求,研制了一种输出电压±0.5~±10 kV可调、最大平均功率约3 kW、双极性一体化直流高压充电电源。设计上采用控制电路与正负双极性直流高压输出主电路一体化方式,通过隔离、屏蔽和保护措施,解决了目前双极性直流高压充电电源存在的正负极性电压不平衡、采样控制信号与高压地未隔离问题,减小了电源体积,提高了电源的鲁棒性、可靠性和电磁干扰能力。100多台充电电源在18.3 MJ脉冲装置中同时运行,在复杂电磁干扰环境下可靠稳定工作。 相似文献
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LED发光二极管在发光时约有80%以上的功率转化成了热能,导致LED发光二极管的PN结温度过高,这是影响LED发光二极管的发光效率与照明功能的主要因素。本文针对上述问题,结合现实情况,设计了一种自动跟踪LED驱动电压的控制电路,从串联稳流单元采样一个电压信号,与本控制电路中的基准电压相比较,产生一个控制信号,去控制所述串联稳流单元前级的开关稳压电源,使它的输出电压随LED灯的工作电压的变化而变化,不增加调整管的功耗。避免了常见的恒压驱动亮度变化大的缺陷,从而大幅度提高LED发光二极管的工作效率,该控制电路结构简单、成本低、损耗小与可靠性高。 相似文献
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Converting mechanical deformation from surrounding environment into detectable electrical signals remains one of the most attractive fields due to its potential applications in sustainable energy harvesting, self-powered sensors, and others. Presently, deformation energy is harvested by generating voltage/current through bending/twisting of piezoelectric materials, but its recyclability is limited in number. In contrast, polarization is generated in all known insulators/semiconductors due to elastic strain gradient, which offers unique electromechanical coupling and in turn, could generate significant potential differences to drive charge transfer. Here, we demonstrate that extremely high direct current with density of 28 × 106 A m−2 is generated without need of any external power supply by applying pointed force using conductive-atomic force microscope (cAFM) tip on multilayer graphene/substrate (SiO2, Si, glass). Further, the ramp-dependent time-resolved current is measured at a localized point, which indicates that pointed force-induced flexoelectric potential differences are the main driving factor to utilize mechanoelectrical coupling and in turn generate high current density. This research work provides a new strategy to utilize the flexoelectric effect to utilize electromechanical coupling to generate giant energy harvesting, which will have a potential impact on the various multiple fields including smart devices, materials, and even a fundamental understanding of physics. 相似文献
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Based on physical theory, a new concept for achieving high efficiency in a solid-state laser power supply charging circuit is first introduced in this paper that is, from the fact that when an electron from a power source enters the energy storage capacitor, a potential drop would occur in this process. This potential drop is the essence of the energy loss in a charging circuit. If the potential drop is small, or even negligible, power supply with a higher efficiency can be achieved. According to this design theory, a highly efficient charging circuit can be obtained if a power source with a single continuous increased voltage slightly higher than that of the energy storage capacitor is employed. With the use of this proposed technique, a prototype of a pulsed YAG laser power supply with high charging efficiency and high voltage charging precision is implemented. The design idea and the experimental results are described and discussed in detail. 相似文献
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纳米光子学,产生于纳米技术和光子学的交界处,处理光和物质在纳米尺度的相互作用,可以被用来产生新的效果和发展纳米尺度的器件。世界在迎接未来能源需求方面正面临巨大挑战。纳米光子学为太阳能转换提供了新的进展。在太阳能转换领域,我们正加速开展新的基于纳米光子学让太阳光子在整个光谱范围从紫外到红外有效率地被吸收和转换,并且有效率地转换为电能方面的研究(比如直接或者电化学的转换)。纳米技术也为热电和能量储存方面的研究提供了新的途径,我们正追求把它们和太阳能获取整合在一起从而提供广泛的能源解决方案。 相似文献
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随脉冲功率技术向高重复频率、长寿命等方向发展,储能元件和开关元件在瞬态强场条件下的稳定性能检测十分必要。基于固态开关技术研制了一种百kV,μs时间尺度下的瞬态强场测试平台,主要由高压直流充电电源、初级单元、脉冲变压器、磁脉冲压缩网络、复位系统和测试腔体组成,实现了一体化结构,使用便利。首先,针对电容器测试条件,建立了完整的电路模型,详细设计了系统中各关键参量;然后,利用晶闸管组件作为初级单元控制开关,利用磁开关进行两级脉冲压缩,建立了实验装置;最后,给出了40 nF小批量陶瓷电容器的典型实验测试结果,测试电压50 kV,脉冲宽度1 μs,重复频率10 Hz,运行时间85 min(对应51 000个脉冲),平台稳定可靠性良好,为后续开展相关测试研究奠定了基础。 相似文献
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RL Harne 《The Journal of the Acoustical Society of America》2012,132(1):162-172
Conversion of ambient vibrational energy into electric power has been the impetus of much modern research. The traditional analysis has focused on absolute electrical power output from the harvesting devices and efficiency defined as the convertibility of an infinite resource of vibration excitation into power. This perspective has limited extensibility when applying resonant harvesters to host resonant structures when the inertial influence of the harvester is more significant. Instead, this work pursues a fundamental understanding of the coupled dynamics of a main mass-spring-damper system to which an electromagnetic or piezoelectric mass-spring-damper is attached. The governing equations are derived, a metric of efficiency is presented, and analysis is undertaken. It is found that electromagnetic energy harvesting efficiency and maximum power output is limited by the strength of the coupling such that no split system resonances are induced for a given mass ratio. For piezoelectric harvesters, only the coupling strength and certain design requirements dictate maximum power and efficiency achievable. Since the harvesting circuitry must "follow" the split resonances as the piezoelectric harvesters become more massive, the optimum design of piezoelectric harvesters appears to be more involved than for electromagnetic devices. 相似文献