基于DSP的电容电流测试仪的设计

Design of Capacitive Current Measuring Equipment Based on DSP

为了实现配电网电容电流的安全、准确和自动检测,提出了采用附加电阻法,基于数字信号处理器(DSP)的电容电流测试仪的设计方案。内置有A/D转换器、处理能强的DSP—TMS320LF2407A为计算和控制的核心。单相对地附加电阻测量的新方法使测试仪在电网正常运行时,即可预测出电网单相接地时的电容电流。快速傅里叶分析(FFT)等数字信号处理算法的使用,简化了测试仪的硬件设计。论文给出了该微机型电容电流测试仪的硬件设计和软件系统结构。与现有单片机型的测试系统相比,基于DSP的电容电流测试仪具有安全、准确、迅速、便携及操作简单等特点;是集测量、通信、状态记忆、自诊断和人机交互等功能于一体的智能化装置。

In order to realize capacitive current measurement of distribution network safely, exactly, automatically, measuring equipment, that make use of digital signal processor and additional resistance method, is presented. DSP--TMS320LF2407A, which have analog-to-digital converters and powerful processing capacity, is the computing and controling core. single-phase ground fault capacitive current is predicted in good runing condition of distribution network by adding a resistance to line. Using fast fouriter transform algorithm, hardware of capacitive current measuring equipment is simplified. The design of hardware and the frame of software are all discussed. Compared with existing measurement system based on single chip microcomputer, this new capacitive current measuring equipment is more safety , more accurte, more fast, easier to operate and take. It is a intelligent device integrating functions of measurement, conmunica- tion, self-diagnosis, state memory, man-machine interaction.