摘要
本文介绍了一种基于现场可编程逻辑门阵列FPGA和微控制器MCU设计的高性能数字式电桥的系统结构。数字电桥采用了伏安法的自由轴测量原理;激励信号使用直接数字频率合成技术,产生了失真度小、幅值稳定的正弦信号;采用了全数字相敏检波技术,大大提高了鉴相的精度;设计了专用的积分A/D转换器,提高了转换的精度。该数字电桥基本测量精度达到了0.01%,同时具有数据处理、自校准、自修正、自诊断及显示各种测试条件、参数和结果等功能。
A high digital bridge based on field programmable gate array （FPGA）and micro controller unit （MCU）is introduced in this paper. In this system, the free-axis measurement principle on V-I method is employed, direct digital synthesis is applied to produce little-distortion and stable amplitude sine as test signal, and full digital phase sensitivity detection technique is also applied to enhance precision of measurement. Integrating AID converter is special designed to improve precision of conversation. The measuring accuracy of digital bridge is 0.01%, and the instrument has the functions of data processing, self-calibration, self-adjusting, self-diagnosis and display each test condition, parameter and result.
出处
《电测与仪表》
北大核心
2009年第10期63-66,共4页
Electrical Measurement & Instrumentation
关键词
现场可编程门阵列
微控制器
自由轴法
直接数字频率合成
相敏检波
双积分转换器
field programmable gate array, micro controller unit, vector-free-axis method, direct digital synthesis,digit-phased method, integrating A/D converter
