共查询到20条相似文献,搜索用时 46 毫秒
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光伏发电系统充放电控制策略研究 总被引:1,自引:0,他引:1
本对光伏发电系统中影响蓄电池寿命各因素进行了简单分析,并在此基础上提出了一种新的充放电控制策略。实验结果证明该控制策略能较显提高蓄电池的放电容量。 相似文献
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A new fiber optic displacement sensor (FODS) is proposed and demonstrated using a multimode fiber coupler as a sensor probe and a concave mirror as a reflective target. A mathematical model is also developed to investigate the performance of proposed FODS at various coupling ratio, fiber diameter, and surrounding media. Three slopes are obtained for the displacement response where the third slope starts at a displacement position of twice the focal length. The numerical results show that higher performance is attained at lower coupler ratio of 50:50 or smaller core diameter. The results also show that the proposed FODS has a potential application in liquid and gas chemical sensors. The experimental performances are also investigated for the proposed sensor where it is observed that the second peak of the displacement curve is located at exactly two times of the focal length or 20 mm. 相似文献
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This paper describes a fiber optic sensor suitable for remote sensing and multi-point detection of ultrasound. This ultrasound sensor is based on the surface-bonded fiber optic Sagnac interferometer with the output fringe visibility of 1; it consists of a laser source, an ordinary single mode fiber delay line, a fiber coupler, a phase modulator and polarization controllers. For the validation of the sensor, surface acoustic waves and Lamb waves are excited by illuminating a steel specimen with an array of Q-switched Nd:YAG laser-generated line sources and the measurement of laser-generated ultrasonic waves are performed on the specimen surface using the surface-mounting fiber optic Sagnac sensor. The surface-bonded fiber optic sensor developed in this study has a simple configuration for detection of ultrasonic waves. Effectiveness of surface-bonded fiber optic Sagnac sensors for remote sensing of ultrasound and in situ monitoring of structures is investigated. The capability of multi-point detection of ultrasound by this Sagnac sensor is also discussed. 相似文献
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电流变材料构件的频率检测与响应控制 总被引:4,自引:0,他引:4
干涉式光纤应变传感器为构件的实时频率检测提供了抗电磁干扰的新型最佳技术手段.本文分析了其在新型的电流变材料构件应用时的若干现象.提出一个位相漂移模型并用以成功处理了有关问题.由此设计的嵌埋型干涉式光纤应变传感器首次使用于受到随机外部激励的电流变结构的振动控制过程. 相似文献
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Jiangdong Deng Hai Xiao Wei Huo Ming Luo Russ May Anbo Wang Yilu Liu 《Optics & Laser Technology》2001,33(5):72
In this paper, a fiber optic acoustic sensor system is designed and tested for on-line detection of the partial discharges inside high voltage power transformers. The fiber optic sensor uses a silica diaphragm and a single mode optical fiber encapsulated in a silica glass tube to form an extrinsic Fabry–Perot interferometer. Test results indicate that the developed fiber optic sensors are capable of detecting the acoustic signals propagating inside the transformer oil with high resolution and high frequency. 相似文献
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光纤电压传感器温度特性的研究 总被引:6,自引:2,他引:4
以半波电压较高的石英晶体为敏感材料,分析了光纤电压传感器全量程的温度特性,发现其与传感器所测电压值要关;随着待测电压的从小往大增加,其输出温度变化的灵敏度逐渐由小变大。为了实现电压传感器全量程的温度补偿,必须获取两个关键的参数:一为电压传感器在无外加电压作用下的温度输出响应参数;二是敏感材料在电压作用下的温度应参数。 相似文献
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光纤传感器系统中的功能光纤 总被引:2,自引:0,他引:2
本文结合光纤传感器的应用实例,对光纤传感器中光纤的选用进行了比较详细的讨论.光纤传感器是一种新型和具有一定特殊应用的传感器,如光纤陀螺、光纤流量计等,由于其自身的特点,具有其他传感器无法替代的优势.在这些传感器中,光纤的选用是致关重要的,特别是传感器用光纤的特性及对光纤传感器的影响;本文提出了光纤传感器设计过程中选用光纤的一些重要依据并论及了发展传感器用光纤对光纤传感器的重要意义. 相似文献
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分析了用一个传感头实现双参量测量的偏振调制光纤传感器的工作原理,表明该传感器能同时输出两路信号,其中一路利用泡克耳斯效应测电压或利用光弹效应测压力,另一种利用旋光效应测温度。但其输出的两个测量参量之间存在交叉敏感现象,并且其输出呈明显的非线性。因此提出一种基于人工神经网络的双参量偏振调制光纤传感器输出信号分离与线性化方法。以传感器输出作为输入样本,测量参量的实际值作为输出样本,通过训练使神经网络建立传感器输出与其实际感受的测量值之间的复杂非线性关系。计算机仿真与实验结果表明,该方法不仅能在较宽的测量范围内有效地分离两个测量参量,而且能在神经网络的输出端得到理想的线性输出。 相似文献
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讨论了光纤表面等离子体波传感器的工作原理,并对将其用于监测以甲基橙为代表的环境污水降解过程的可行性进行了探讨。用光纤SPR传感器监测了50 mL初始浓度为30 mg·L-1的甲基橙原溶液在降解过程浓度的变化,对降解过程中光纤SPR传感器的光谱进行了详细的分析;同时采用紫外-分光光度计对降解过程中溶液浓度的变化进行了监测,并对2种方法所测的数据进行了分析对比。结果表明,光纤SPR同常规方法的测量结果一致,随着降解时间的增加,甲基橙溶液的吸光度和浓度逐渐减小,光纤SPR传感器的共振波长逐渐发生蓝移,同初始标定的甲基橙原溶液共振光谱比较,说明甲基橙逐渐被降解,且在2 h内降解率达到73%,说明用光纤SPR传感器监测污水降解过程是完全可行的。研究结果不仅为环境污水降解过程提供了一种新的监测方法,同时促进了我国SPR传感技术与环保监测研究结合,为光纤SPR技术走向实用,并最终实现产业化积累了经验。 相似文献
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混合型大电流光纤传感器的研究 总被引:3,自引:1,他引:2
本文叙述了混合合型大电流光纤传感器的工作原理及制作方法.以LED作光源、PIN作接收、火石玻璃为磁感应材料、多模光纤作导光波导的混合型大电流光纤传感器,用于监视高压电网系统中的电流.适用范围10~2~10~4A,精度±0.5%. 相似文献
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A reflective fiber optic displacement sensor has been developed and calibrated to gauge form and axis position of shafts during rotation. A technique has been implemented to determine the deviation of the actual shaft form from its nominal circular cross section (the off-round error) and the departure of the rotation axis from the geometric axis (the eccentric error). The sensor is simple, has acceptable accuracy for applications to mechanical engineering, is capable of monitoring shafts during rotation, and has potential for gauging parts on the production line. 相似文献
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We report a new approach to analyze both vapor and liquid phases by utilizing a tapered fiber optic surface plasmon resonance (SPR) probe. This technique employs a fiber optic SPR probe with a modified geometry to tune the SPR coupling wavelength-angle pair. The observed composite spectrum included two distinct SPR dips associated with surface plasmons excited in the gas and liquid active regions. This sensor is able to detect refractive index changes in both vapor and liquid phases individually by simultaneous monitoring SPR coupling wavelengths from the two sensing surfaces. 相似文献
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M. Rajesh K. Geetha M. Sheeba P. Radhakrishnan C.P.G. Vallabhan V.P.N. Nampoori 《Optics and Lasers in Engineering》2006,44(5):486-493
A simple, effective and inexpensive fiber optic sensor for investigating the setting characteristics of various grades of cement is described. A finite length of unsheathed multimode optical fiber laid inside the cement mix, is subjected to stress during the setting process. The microbends created on the fiber due to this stress directly influence the intensity of light propagating through the fiber. Continuous monitoring of such variations in the light output transmitted through the fiber gives a clear measure of the setting characteristics of the cement mix, thus providing a simple and elegant technique of great practical importance in the field of civil engineering. The smart fiber optic sensor described above can be incorporated into a building during the construction process itself so that continuous monitoring of the deterioration process for the entire life time of the building can be carried out. 相似文献
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Sagnac fiber optic current sensor (S-FOCS) is a kind of optical interferometer based on Sagnac structure, optical polarization states of sensing light wave in Sagnac fiber optic current sensor are limited. However, several factors induce optical polarization error, and non-ideal polarized light waves cause the interference signal crosstalk in sensor, including polarizer, quarter-wave retarder, splice angular, birefringence and so on. With these errors, linearly polarized light wave in PM fiber and circularly polarized light wave in sensing fiber become elliptically polarized light wave, then, nonreciprocal phase shift induced by magnetic field of the current is interrupted by wrong polarization state. To clarify characteristics of optical polarization error in fiber optic current sensor, we analyze the evolution process of random optical polarization state, linear optical polarization state and circular optical polarization state in Sagnac fiber optic current sensor by using Poincare sphere, then, build optical polarization error models by using Jones matrix. Based on models of polarization state in Sagnac fiber optic current sensor, we investigate the influence of several main error factors on optical polarization error characteristics theoretically, including extinction ratio in polarizer, phase delay in quarter-wave retarder, splice angular between quarter-wave retarder and polarization maintaining fiber. Finally, we simulate and quantify nonreciprocal phase shift to be detected in fiber optic current sensor related with optical polarization errors. In the end, we demonstrate S-FOCS in test. The results show that transfer matrix errors are induced by inaccurate polarization properties during polarization state conversion, then, the stability and accuracy of the S-FOCS are affected, and it is important to control the polarization properties at each step of the polarization state conversion precisely. 相似文献
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In this paper, a fiber optic sensor based on fiber Bragg grating (FBG) is employed to measure the ground vibrations which may be generated by earthquakes, debris flows, landslides, and rock impacts on the ground. The detected vibration signals were analyzed by both fast Fourier transform (FFT) and Gabor transform to obtain the frequency response. The performance of fiber optic sensor was examined and compared with the conventional ground vibration geophone sensor. From the results of field tests, the fiber optic sensor shows highly similarity with conventional geophone sensor for low frequency measurement. The fiber optic vibration sensing system presented in this research is appropriate for sensing ground vibration in the frequency ranges of 10–250 Hz. The sensor proved to be an alternative option for ground vibrations monitoring system. 相似文献