幅值误差和相位误差对反馈系统的影响*

摘要

In general,there are some errors in the feedback system consisting of amplifiers. While the influence of the feedback system caused by different errors is also different. In the analysis of the feedback system,many people only pay attention to the influence of the amplitude error,while ignore the influence of the phase error. It will make affects to the precision of the feedback system. So in this paper,there are amplitude error and phase error in the feedback system through analysis of the common feedback amplifier. And then,we find that the influence caused by amplitude error and phase error is very different by specific example. At last, the results of MATLAB simulation and validation of experiment show that the influence of amplitude error is much bigger than the influence of phase error. So the influence of the phase error should be paid more attention to in the analysis of the feedback system.%在放大器所组成的反馈系统中通常会产生一些误差，然而不同的误差对反馈系统所造成的影响也不同。在对反馈系统的分析中，很多人只注意到幅值误差的影响而忽略了相位误差的影响，这将会对反馈系统的精度造成影响。对此，本文先通过对普通反馈放大器的分析得知反馈系统中存在幅值误差和相位位差，然后再通过具体实例计算发现幅值误差和相位误差对反馈系统的影响相差很大，最后通过MATLAB仿真以及实验验证后发现，相位误差的影响比幅值误差的影响更大。因此，在对反馈系统的分析中，相位误差的影响也应加以重视。