基于FPGA的科氏质量流量计数字闭环系统设计

设计一种科氏质量流量计(Coriolis mass flowmeter,CMF)数字闭环系统,实现CMF稳定闭环工作条件.采用高速数字电路以及现代信号处理技术取代了传统的模拟正反馈系统来实现CMF闭环控制,使CMF测量管稳定维持在简谐振荡状态.利用模拟数字转换电路(A/D)将传感器输出的信号完整采样,借助现场可编程器件(FPGA,Field Programmable Gate Array)对信号进行分析与处理,根据信号特性进行相应的数字滤波、幅值解算,实现CMF闭环系统的幅值增益和相位的精确控制.实验结果表明:该数字闭环系统具有动态特性好、稳定性好等优点.

Design of Digital Closed Loop System of Coriolis Mass Fowmeter Based on FPGA

Adigital closed loop system for Coriolis Mass Flowmeter(CMF)was introduced to realize stable closed-loop running condition.The high speed digital circuits and digital signal processing methods were used to realize closed-loop control,and maintain flow tube oscillation instead of conventional analog positive feedback system.Analog to digital converter(A/D) was utilized to sample the whole signals of the sensor.The sample data were analyzed and processed by the field-programmable gate array(FPGA).Classical signal processing method was used to filter the sample data and control the amplitude and phase position,which achieves accurate controlling of amplitude and phase position in the CMF closed loop system.The experimental results show that the dynamic response and stability of the system is improved.Furthermore,the resulting meter is able to maintain the operation in more difficult process conditions.