数字有源 EMI 滤波系统延迟的建模与分析

摘要

With the development of the digital processing technology,and the sharp increasing of the speed and accuracy of data acquisition,the DAEF technology becomes a new direction of the EMI filter technology.As the frequency of EMI signal is high,the delay time of system has great impact on system performance and cannot be ignored,which needs more study.In this pa-per,the reason of the delay time existence was analyzed in the DAEF system,and with consideration of delay time the model of DAEF system was built.The impact of the delay time on the EMI filter performance was analyzed by simulation.The DAEF control system platform was built based on FPGA.The correctness of the DAEF model with delay character was verified.The influence rule of delay time on the filter performance of DAEF system was revealed.The results help to further study and widespread application of digital active EMI filter.%随着数字处理技术的进步，数据采集速度与精度的大幅提高，使得数字有源电磁干扰滤波技术 DAEF （Digital Active EMI Filter）成为 EMI（Electro-Magnetic Interference）滤波技术发展的新方向。由于 EMI 信号频率较高，所以EMI 滤波控制中的延迟对滤波性能的影响不可忽视，需要深入研究。本文详细分析了数字有源 EMI 滤波系统中产生延迟的原因，建立了具有延迟特性的数字有源 EMI 滤波系统模型，仿真分析了延迟时间对 EMI 滤波系统滤波性能的影响。搭建了基于 FPGA（Field Programmable Gate Array）的数字有源 EMI 控制系统平台，验证了具有延迟特性的数字有源EMI 滤波系统模型的正确性，揭示了数字有源 EMI 滤波系统延迟环节对滤波性能的影响规律，这有助于对数字有源EMI 滤波器的进一步研究和推广应用。