【作者】 王晓娜；

【导师】 吴石增；

【作者基本信息】 中国科学院研究生院（电工研究所） ， 电力电子与电力传动， 2003， 硕士

【摘要】 本论文主要介绍了课题所做的低频电磁场电流测控系统的研制、开发工作，详细阐述了系统的软、硬件设计思想，并着重分析了课题研究中所做的一些改进和创新。低频电磁场电流测控系统包括电流测试和输出控制两个部分，由软件和硬件相互配合组成一个完整的计算机控制系统。控制系统包括硬件部分和软件部分，硬件部分主要包括电流电压传感器、与CPU的接口电路、数据采集电路以及电流频率、幅值控制器件；软件部分则一方面通过对采集到的电流数据进行分析，实时显示当前电流参数如波形、频率、幅值，另一方面对不合要求的电流参数进行调整，从键盘输入所需的参数数值，通过计算机输出的控制电流或电压从而实现对电源参数的控制，此外还对计算机输出参数可变的方波、正弦波、指数形波做了一些探索和讨论。本课题所做的改进和创新主要有：在硬件设计上，采用了新型磁补偿式霍尔传感器将输出电流和电压变换为适合计算机采集的电压信号；软件设计方面，在对方波进行频谱分析的基础上，确定采样频率和显示方式；根据不同的控制硬件确定电流的控制策略，设计参数算法；在Windows操作系统下采用Visual Basic语言编程，用户界面友好，为低频电磁场的使用人员提供了很大的方便。在本课题中，为了简化系统的硬件设计，增强系统智能化，还讨论了利用软件编程从计算机端口输出各种波形的方法，并初步探索了滤波方法，运用该方法滤波后得到的波形放大后也可直接作为信号源。另外，本文对低频电磁场发生装置原理、计算机接口与数据传送方式、方波频谱分析也进行了较详细的讨论。更多还原

【Abstract】 This paper mainly introduces the development of the Current Measurement and Control System in a Low-frequency Magnetic Field. The design method of the system is expounded in detail and some improvement in the task is emphasized.The Current Measurement and Control System in a Low-frequency Magnetic Field is a comprehensive system of hardware and software, including two parts: current measurement and computer control. The system hardware design consists of current and voltage sensors, CPU interface, data sampling circuit and current, frequency control parts. The system software comprises the display of waveform, number of frequency and amplitude and the control of current parameters. What’s more, some study of variable parameters waves are displayed in the paper.The improvement of this system is made in following aspects. A new type sensor is employed to transfer the current to appropriate voltage, which can be sampled by the computer. The operating system of PC Bus industrial computer software has changed from DOS to Windows. The sampling frequency is determined on the basis of spectrum analysis and the arithmetic design for control is discussed. Also, three kinds of wave is output through computer programming. It may simplify system hardware design and after amplified, the wave can be used as signal source.Furthermore, the low-frequency magnetic field generator, computer interface and data transmission method, square wave frequency spectrum are also discussed in this paper.更多还原