基于FPGA的多路传感信号采集系统设计

Design of Multi-channel Sensor Signal Acquisition System Based on FPGA

为满足无人机动态监测系统对多路热电偶、光电信号并行采集的可靠性、数据传输的稳定性要求,设计以FPGA为核心的多路数据采集系统,该系统通过对4片高精度模数转换芯片ADS1248的逻辑控制,实现对10路热电偶信号、5路光电信号及1路冷端补偿信号的实时采集,并通过冷端补偿算法对热电偶测量误差进行修正。实验结果表明:400℃以下时,K型热电偶在温度补偿后测量误差小于±2.5℃;400℃以上时,测量误差小于±1%t。并且光电测量,穿孔破坏时间误差小于50 ms,满足预期目标。

In order to meet the reliability and data transmission stability requirements of the UAV dynamic monitoring system for the parallel acquisition of multi-channel thermocouple and photoelectric signals,a multi-channel data acquisition system based on FPGA was designed.Through the logic control of four high-precision analog-to-digital conversion chips ADS1248,the real-time acquisition of 10 thermocouple signals,5 photoelectric signals and 1 cold-junction compensation signal were collected.The thermocouple measurement error of the system was corrected by cold-junction compensation algorithm.The experimental results show that the measurement error of type K thermocouple is less than±2.5℃(below 400℃)and less than±1%t(above 400℃)after temperature compensation,and photoelectric measurement and perforation failure time error is less than 50 ms,meeting the expected targets.