摘要
涡街信号的幅值随频率成平方关系而变化,输出信号幅值的差别很大。为了保证测量精度,要求信号幅值控制在一个合适的范围内。为此,采用数字电位器和低功耗运算放大器研制了一种程控放大器。通过TMS320LF2407A DSP芯片计算涡街信号的绝对平均值来确定和调节放大器的增益,以适应涡街信号幅值的变化。实验结果表明,程控放大器的设计和幅值调整方法是有效的。
The variation of a vortex signal amplitute is proportional to the square of a vortex frequency, so there is a great difference in the output signal amplitute. In order to keep the measurement accurate, its signal amplitute needs adjusting to an appropriate level. Therefore, a programmable control amplifier is designed by using digital potentiometers and a low-power operating amplifier. Its gain is determined and adjusted according to the abslolute mean value of the vortey signal calculated by the TMS320- LF2407A DSP chip, which can adapt itseff to the variation of the vortex signal amplitute. The experimental results demonstrate that both the design of the programmable control amplifier and the amplitute adjusting method are effective.
出处
《工业仪表与自动化装置》
2009年第1期25-27,60,共4页
Industrial Instrumentation & Automation
基金
863计划资助项目(2007AA04Z180)
关键词
涡街流量计
程控放大器
信号幅值调整
vortex flowmeter
programmable control amplifier
signal amplitude adjustment
