一种多通道多功能数据采集系统的设计与实现

Design and Implementation of a Multi-Channel and Multi-Functional Data Acquisition System

为解决航空发动机试验中采用多种仪器采集多种信号数据引起测试系统成本和复杂度增加的问题,设计了一种利用单一硬件资源进行多种模拟信号采集的多通道多功能数据采集系统。系统通过电子开关矩阵和独特的切换策略实现4种信号采集的功能,克服了现有通用数据采集系统大多只能采集一种或少数几种类型数据的缺点。利用状态机任务调度实现校准、配置和通信等功能,采用通道隔离技术,实现每个通道信号全隔离,提高系统的抗干扰性。通过校准实验结果和现场应用可知,系统能够采集电压、电流、热电阻、热电偶等信号,电压电流精度可达±0.05%,Pt1000和K型热电偶精度可达±1℃。系统的性能指标满足发动机试验要求,且有效地降低了成本,减小了现场布线复杂度和劳动强度,在航空发动机试验的稳态电参数测量中具有一定的工程应用价值。

In order to solve the problems of increasing the cost and complexity of the test system caused by the use of multiple instruments to collect various signal data in the aeroengine test,a multi-channel and multi-functional data acquisition system is designed,which uses a single hardware resource to collect a variety of analog signals. The system realizes four kinds of signal acquisition functions through electronic switch matrix and unique switching strategy,which overcomes the shortcomings that most of the existing general data acquisition systems can only collect one or a few types of data. The state machine task scheduling was used to achieve calibration,configuration,communication and other functions,and the channel isolation technology was adopted to achieve full isolation of each channel signal and improve the anti-interference of the system. The results of calibration experiments and field application show that the system can collect voltage,current,thermal resistance,thermocouple and other signals. The accuracy of voltage and current can reach ± 0. 05%,and the precision of Pt1000 and K-type thermocouples can reach ± 1 ℃ . The performance index of the system meets the requirements of engine test,and effectively reduces the cost,reduces the complexity of field wiring and labor intensity.It has a certain engineering application value in the measurement of steady-state electrical parameters of aeroengine test.