Design of High Precision Synchronous Data Acquisition System with Temperature Compensation

摘要

Aiming at the problem that the electromagnetic environment of the aeroengine inlet test space is complex, the temperature range is large, and the test accuracy is seriously affected, a high-precision synchronous data acquisition system with temperature compensation is designed. The advantage of this system is: a gain error calibration model with temperature compensation is established, which effectively reduces temperature drift and quantization errors; An oversampling-decimation filtering algorithm is designed to well filter the noise interference in the system; A PID algorithm based on the clock phase-separated measurement time difference is proposed to realize the clock synchronization between the local pulse per second (1pps) and the external 1pps, which meets the needs of data fusion analysis between different test systems. Finally, the histogram analysis method is used to analyze and compare the collected data in different working modes. The results show that the method can effectively reduce the measurement error of the system and improve the system test accuracy; And the synchronization characteristics of the system were tested, the results show that the synchronization accuracy of the system is better than 150ns, which meets the requirements of data fusion analysis between different systems.