【作者】 黄浩；

【导师】 陆继明； 毛承雄；

【作者基本信息】 华中科技大学 ， 电力系统及其自动化， 2004， 硕士

【摘要】 直流大电流测量技术在工业生产和科研试验中都有着较为广泛的应用。随着直流用电量的越来越大,直流大电流测量也随之成为当前迫切需要解决的问题,同时对测量仪器也提出了更高的要求。本文结合所在课题组成功申请的国家自然科学基金项目——多路罗柯夫斯基直流大电流智能化传感器研究而展开。在综合了解直流大电流各种主要测量原理的基础上,本文选择对罗柯夫斯基(Rogowski)线圈和直流比较仪这两种原理进行深入研究,为直流大电流传感器的开发建立良好的理论基础和实验指导。在深入研究罗氏线圈测量原理、结构设计方法的基础上,论文推导出其电气参数与结构参数的关系,用结构参数建立系统传递函数,并建立了Matlab软件下的仿真模型。通过对不同结构参数下的仿真结果(时域和频域特性)进行比较,总结出结构尺寸对线圈特性的影响规律,提出优选方法。在尝试将罗氏线圈应用到直流测量领域中,还有个重要的问题是如何实现线圈与环形磁场间的相对运动,本文设计并进行了两个实验方案,探讨将罗氏线圈用以直流大电流测量的方法。对于直流比较仪的测量方案而言,有两个核心的问题:其一是磁性材料性能参数的选择,尤其是对磁化曲线的选择。本文提出了取多个采样点分段拟合的方法来模拟磁化曲线。其二是如何判断环形磁芯中的直流磁势是否平衡。在研究了现有的几种判断方法后,本文提出了一种比较检测线圈输出波形的磁放大方案。通过进行的仿真分析和所设计的实验,验证了手动调节反馈直流的磁放大器直流比较仪测量方案的可行性,为该方案建立了初步的传感器模型。最后,论文提出了通过运用单片机将该方案改进为自动调节的方案设想,指出在测量精度和误差上需要改进的方法。更多还原

【Abstract】 Heavy direct current (DC) measurement has been widely used both in manufacturing and scientific researching. With more and more direct current power absorption, it is very urgent to develop the methods and instruments for heavy DC measurement to meet such requirement. This treatise is ground on the item of National Natural Science Fund “the research of multiplex Rogowski coils intelligent heavy DC sensors”. According to our comprehension on the main principia of heavy DC measurement, we determine to study the theory of Rogowski coil and DC comparator., for making a good foundation in theoretically and experimentally. After lucubrated the measuring elements and the method of design, we reckoned the relation of the coil’s electric parameters and dimension parameters. Then we get the system function figuring with the dimension parameters, and founded the simulation model under the environment of MATLAB. By comparing the simulation results of the characteristics both of the time and frequency-domain of the coil with different dimension parameters, the rules of designing proper coil and the choice method of the optimal dimension of the coil have been summarized and proposed. How to realize comparatively movement between the coil and the magnetic field? This is the signify point for DC measurement by using the Rogowski coil. So two experimentations were developed for discussing. On the other hand, there are two important sides for DC Comparator. The first one is the choosing for the capability parameters of the magnetic core, especially the magnetization curve. We make multi-point sampling and subsection to dummy the magnetization curve. Another one is how to judge the balance of the magnetism influence in the core. According to actuality of the present methods, we bring forward a new measurement scheme by comparing the output wave from the detect coil. In order to establish the elementary sensor model, we simulated the mathematics model and carry out a feasible project to dissolve the above problems. At last, the article bring forward the assume for auto-adjustment by using Single Chip Micyoco(SCM), and point out the methods for ameliorating the precision and error of measurement.更多还原