高精度自适应数字移相方法研究  

Research on high precision adaptive digital phase shift method

作　　者：朱革 余小雨[1,2] 付敏 蒲治伟[1,2] 李昌利 张双亚 Zhu Ge;Yu Xiaoyu;Fu Min;Pu Zhiwei;Li Changli;Zhang Shuangya(School of Mechanical Engineering,Chongqing University of Technology,Chongqing 400054,China;Engineering Research Center of Mechanical Testing Technology and Equipment,Ministry of Education,Chongqing Key Laboratory of Time-Grating Sensing and Advanced Testing Technology,ChongqingUniversity of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学机械工程学院,重庆400054 [2]重庆理工大学机械检测技术与装备教育部工程研究中心,时栅传感及先进检测技术重庆市重点实验室,重庆400054

出　　处：《电子测量与仪器学报》2020年第2期107-114,共8页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然科学基金(51875070);国家重大科研仪器研制项目(51827805);重庆市教委科学技术研究项目(KJQN201801105);重庆理工大学研究生创新项目(ycx20192032)资助。

摘　　要：针对传统移相方法精度和稳定性不高的问题,提出一种高精度自适应数字移相方法。该方法基于随机逼近算法和有源RC移相电路构建一个闭环控制系统,通过FPGA配置高精度的数字电位器,检测实际输出相位并作为随机逼近算法的观测值,经过多次迭代计算电位器电阻参数,使输出相位值逐步逼近设定相位值。移相精度和稳定性实验结果表明,在数字电位器可调范围内,移相误差不超过±0.3°,同时在至少11 h内移相误差不超过±0.25°,环境温度快速变化约20℃过程中,移相误差不超过±0.3°;实际应用实验表明该方法具有良好的鲁棒性和实用性。该自适应数字移相可为高精度移相提供一种新方法。Aiming at the problem of low precision and stability of traditional phase shifting methods, a high precision adaptive digital phase shifting method is proposed. The method is based on stochastic approximation algorithm and active RC phase shifting circuit to construct a closed-loop control system. Configuring a high-precision digital potentiometer via FPGA, then detect the actual output phase and use it as an observation of the stochastic approximation algorithm. After many iterations, the potentiometer resistance is calculated and the output phase value gradually approaches the set phase value. The experimental results of phase shift accuracy and stability show that within the adjustable range of the digital potentiometer, the phase shift error does not exceed ±0.3°, and the phase shift error does not exceed ±0.25° for at least 11 hours. The phase shift error does not exceed ±0.3° during a rapid change in ambient temperature of approximately 20℃. Practical application experiments show that the method has good robustness and practicability. This adaptive digital phase shift provides a new method for high precision phase shifting.

关 键 词：自适应 数字移相 闭环控制 随机逼近 FPGA 

分 类 号：TN791[电子电信—电路与系统] TN623