闭环加速度计的控制数字化分析  

Analysis of digital controller for closed-loop accelerometer

作　　者：苗新法[1] 王秀华[2] 张明柱[1] 吴荣斌[1] 

机构地区：[1]兰州交通大学电子与信息工程学院,兰州730070 [2]兰州交通大学自动化与电气工程学院,兰州730070

出　　处：《中国惯性技术学报》2014年第2期242-247,共6页Journal of Chinese Inertial Technology

基　　金：甘肃省自然基金(1310RJZA055)

摘　　要：加速度计实现数字化有利于系统集成,但随之引入的延时和量化噪声会影响系统的控制稳定性及测量分辨率。为保证闭环系统数字化后仍具有足够稳定裕度,分析出了延时的主要来源为离散化引入的等效时延和检测与控制的不同步,并得出其对系统稳定性的定量化影响。研究了采样频率及量化噪声对输出的影响,提出利用过采样的方法可以有效减小量化噪声对闭环系统输出的影响,从而可提高系统的检测分辨率。最终,建立了进行数字化控制器采样频率的定量化选择依据。用Matlab/Simulink进行了仿真并进行了实验研究,仿真结果及实验结果与理论分析能较好吻合。The digitization of accelerometers is beneficial to the system integration, but the time delay and quantization noise are brought in with the digitization process, which affect the system control stability and detection resolution. To ensure the digitalized closed-loop system has enough stability margin, the analysis is made which show that the equivalent time-delay due to digitization and the out-of-sync of the detection and control are the main time-delay sources, and the quantification effect on the system stability are obtained. The effect of sample frequency and the quantization noise on output is studied. It is proposed that the effect of the quantization noise on output of the system can be reduced efficiently with the oversampling method and then the system's detection resolution can be improved. Ultimately, the principle of selecting the sampling frequency of the digitized controller is established quantitatively. The simulation experiments are made based on Matlab/Simulink. The actual experiments are also made which show that the results are in accordance with the theoretical analysis.

关 键 词：闭环加速度计 数字化 延时 量化噪声 

分 类 号：TH824[机械工程—仪器科学与技术]