Digital staggered cycle control method for digital active EMI filter

Abstract

The invention discloses a digital staggered cycle control method for a digital active EMI filter. The method comprises the following steps: acquiring signals above 150kHz by using a high-pass filter, and then converting analog signals into discrete digital signals through an ADC circuit, performing time and frequency domain processing for the signals through a DAEF controller, reconstructing the converted signals, processing the signals through a DAC circuit after reconstruction, amplifying the signals by using a wide-band high gain amplifier through an EMI injection circuit when a catcher captures rising edge signals or falling edge signals of a switch from the next cycle of a switching power converter, and injecting the delayed signals that are reconstructed in the previous cycle to achieve an EMI suppression effect. According to the digital staggered cycle control method for the digital active EMI filter disclosed by the invention, the problem that the filtering effect is reduced due to the delay of each link of a DAEF can be solved, and the filtering effect of the DAEF can also be improved.

Description

technical field [0001] The invention belongs to the technical field of electromagnetic compatibility of switching power supplies, and in particular relates to a digital staggered period control method of a digital active EMI filter. Background technique [0002] Switching power supply is favored by people for its significant advantages such as low loss, high efficiency, and simple circuit. With the advancement of digital processing technology, especially the extensive development of FPGA based on hardware description language programming and parallel processing capabilities, the computing speed has been doubled. At the same time, the analog-to-digital converter (ADC) and digital-to-analog converter (DAC) The speed and accuracy have also been greatly improved, and the cost of digital processors has been continuously reduced, which makes the digitization of EMI filters possible, and the practical application of digital active EMI filters (DAEF) becomes possible. [0003] Pate...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a digital active EMI filter digital staggered period control method, which solves the problem that the delay of each link in the digital active EMI filter that exists in the prior art reduces the filtering effect of the EMI filter

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