光学 精密工程, 2014, 22 (1): 92, 网络出版: 2014-02-18
数字闭环加速度计的带宽测试
Bandwidth measurement of digital closed-loop accelerometer
数字闭环加速度计 带宽测试 反馈回路 加速度 digital closed-loop accelerometer bandwidth testing feedback loop acceleration
摘要
为了测试数字闭环加速度计系统的带宽,对国军标1037A-2004中的电模拟法进行了改进。首先,讨论了用国军标1037A-2004中的电模拟法测试数字闭环加速度计带宽存在的不足,然后,对加入激励信号的数字闭环加速度计系统的检测电路及闭环控制模型进行分析。分析显示,在系统的反馈回路加入激励信号最终可以在输入端等效为外界输入加速度,且该系统的动态模型与传统机械激励测试法系统的动态模型一致。最后,提出一种在数字闭环加速度计的反馈回路外加激励信号来测试该系统带宽的方法。实验表明: 数字闭环加速度计系统的实测-3 dB带宽值为320 Hz左右,与理论值(345 Hz)基本吻合。该方法具有精度高、误差源少、便于在线测试等特点,可满足大多数数字闭环加速度计的带宽测试要求。
Abstract
To measure the bandwidth of a digital closed-loop accelerometer, the electricity simulation method in GJB1037A-2004 was investigated. First, some drawbacks of measuring the bandwidth of the digital closed-loop accelerometer by using the electricity simulation method in GJB1037A-2004 were discussed. Then, the detection circuit and the closed-loop control system of the digital closed-loop accelerometer with an excitation signal were analyzed. The analysis shows that the effect of excitation signal added into a feedback circuit is equivalent to an input analog acceleration in the input end and the dynamic model of the digital closed-loop accelerometer is consistent with the dynamic model of the traditional mechanical system. Finally, a method which adds the excitation signal at the feedback circuit of the digital closed-loop accelerometer to measure the bandwidth of the accelerometer was proposed. Experimental results indicate that the -3 dB bandwidth data of the digital closed-loop accelerometer is about 320 Hz, which is close to theoretic data (345 Hz). The proposed method has the features of higher accurate, less error sources and convenient to test in online ,and can satisfy the bandwidth testing requirement of most digital closed-loop accelerometers.
张晞, 李德燕, 王洪波, 李立京. 数字闭环加速度计的带宽测试[J]. 光学 精密工程, 2014, 22(1): 92. ZHANG Xi, LI De-yan, WANG Hong-bo, LI Li-jing. Bandwidth measurement of digital closed-loop accelerometer[J]. Optics and Precision Engineering, 2014, 22(1): 92.