基于巨磁效应的光伏系统汇流检测技术研究

发布时间：2018-06-09 04:53

本文选题：光伏系统 + 电流检测　；参考：《昆明理工大学》2017年硕士论文

【摘要】：光伏系统作为"智能电网"的重要组成部分,近年来受到人们广泛关注及科研人员的深入研究。为保证光伏系统的合理、充分、高效运行必须对其发电量进行实时准确的检测。巨磁电阻是近年来迅速发展的一个磁电子学的重要领域,相比于其他类型的电流传感器,具有灵敏度高、线性范围大、体积小、温度稳定性好等优点,因此在电流检测方面具有极高的研究价值及广阔的应用空间。文章首先,对比目前常用的电流检测技术,分析比对各类技术之间的优缺点及应用场合。其次,应用领域探索工作,挖掘电网运行中适合巨磁电阻效应电流传感器的应用场合。通过对光伏系统组成、结构及光伏系统电流检测的特点的全面学习归纳,确定以光伏系统汇流检测为背景研究设计巨磁电阻电流传感器。第三,通过对巨磁电阻工作的基本原理、材料分类及传感器基本结构的研究,提出一种基于巨磁电阻效应的闭环电流传感器结构。第四,针对现阶段大规模使用的霍尔传感器在光伏系统汇流检测中存在的弊端与不足,进行分析及校正研究工作为巨磁电阻电流传感器设计提供理论依据,从而避免类似影响因素对传感器性能造成影响。主要解决环境温度对传感器输出特性的影响、空间位置不确定性对传感器输出特性的影响及磁性材料磁滞等问题。设计传感器主要部件包含电磁转换单元、信号放大单元及反馈补偿单元三大部分,提高了传感器对光伏系统汇流检测的能力。设计温度补偿电路,改善温度对传感器输出特性的影响。采用以常值电阻与温变电阻配合的形式设计温度补偿模块,以调压的方式可有效改善传感器温度特性,减小误差50%以上。通过合理设计磁导环的外形结构,可有效增强载流导线外被测点处的磁场强度。改善因空间角度偏转带入的误差,测试结果误差降低30倍以上。同时也可有效降低空间位置偏移造成误差,测试结果误差降低10倍以上。有效保证了传感器量测精度。利用桥式电路、磁环及反馈补偿绕组构成闭环系统设计方案,进一步降低了传感器的温漂及零漂,也降低了磁性材料由于磁滞效应引入系统的磁滞误差;最后通过仿真分析及试验结果再次验证课题设计的巨磁电阻电流传感器的良好新能。
[Abstract]:As an important part of "smart grid", photovoltaic system has been widely concerned and deeply researched by researchers in recent years. In order to ensure the reasonable, sufficient and efficient operation of photovoltaic system, it is necessary to carry out real-time and accurate detection of its power generation. Giant magnetoresistance (GMR) is an important field of magnetoelectronics which has been developed rapidly in recent years. Compared with other kinds of current sensors, Giant Magnetoresistance (GMR) has the advantages of high sensitivity, large linear range, small volume, good temperature stability and so on. Therefore, it has high research value and wide application space in current detection. First of all, compare the current detection technology, compare the advantages and disadvantages between the various technologies and applications. Secondly, the application field is explored to excavate the application situation of GMR current sensor in power grid operation. Based on a comprehensive study of the composition, structure and characteristics of photovoltaic system current detection, a giant magnetoresistive current sensor is designed based on the background of current confluence detection of photovoltaic system. Thirdly, a closed-loop current sensor structure based on giant magnetoresistance effect is proposed by studying the basic principle of giant magnetoresistance (GMR), the classification of materials and the basic structure of the sensor. Fourthly, aiming at the disadvantages and shortcomings of Hall sensor used in large scale at present in the detection of PV system confluence, the research work of analysis and correction provides theoretical basis for the design of giant magnetoresistive current sensor. In order to avoid the influence of similar factors on the performance of the sensor. The effects of ambient temperature on the output characteristics of the sensor, the influence of spatial position uncertainty on the output characteristics of the sensor and the hysteresis of magnetic materials are mainly solved. The main components of the sensor include electromagnetic conversion unit, signal amplification unit and feedback compensation unit, which improve the detection ability of the sensor to the PV system. The temperature compensation circuit is designed to improve the effect of temperature on the output characteristics of the sensor. The temperature compensation module is designed by matching the constant resistance with the temperature variable resistance. The temperature characteristic of the sensor can be effectively improved and the error can be reduced by more than 50% by adjusting the voltage. The magnetic field intensity of the measuring point outside the current carrying wire can be effectively enhanced by reasonably designing the shape structure of the magnetic guide ring. The error caused by spatial angle deflection is improved and the error of test results is reduced by more than 30 times. At the same time, it can also effectively reduce the error caused by spatial position migration, and the error of test results is reduced by more than 10 times. The precision of sensor measurement is ensured effectively. The closed-loop system is designed by bridge circuit, magnetic loop and feedback compensation winding, which further reduces the temperature drift and zero drift of the sensor, and also reduces the hysteresis error of the magnetic material introduced into the system because of hysteresis effect. Finally, the simulation analysis and experimental results verify the good new performance of the GMR current sensor.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP212;TM615

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