Power frequency digital notch device and method based on frequency track

Abstract

The invention relates to the technical field of digital notch, in particular relates to a power frequency digital notch device and method based on frequency track. The power frequency digital notch method based on the frequency track comprises the following steps: singly collecting power frequency signals and adaptively regulating, analyzing and comparing; and if a comparison result exceeds a set threshold, regulating the coefficient of a power frequency notch filter, and notching a human signal so as to obtain a filtering result, and outputting the filtering result. According to the method, the space power frequency signal can be correctly acquired in real time, the notch is timely traced, the interference of the power frequency signal on a useful signal is effectively attenuated, and the problems that digital notch attenuation amplitude is in lack because of frequency fluctuation of power frequency and the like are solved. In a clinic application, through the device and the method, a wave form is smooth, which is beneficial to correct diagnosis, thereby avoiding misdiagnosis.

Description

technical field [0001] The invention relates to the technical field of digital notch, in particular to a power frequency digital notch device and method based on frequency tracking. Background technique [0002] Electronic equipment often faces various interferences and noises during the working process, the most common one is the power frequency interference (50Hz or 60Hz) of the power grid. Filtering out power frequency interference is an important problem to be solved in the field of signal processing. At present, digital notch technology has been widely used in the processing of power frequency interference. However, the traditional power frequency digital notch filter has a fixed notch center frequency and a narrow effective bandwidth; while the actual power frequency frequency is often not fixed, with a deviation of + / -1Hz, so signals that deviate from the digital notch center frequency are often not attenuated enough. In practical applications such as ECG signal det...

AI Technical Summary

Problems solved by technology

The scheme of using the right leg to drive the power frequency signal has disadvantages such as large signal distortion, low acquisition frequency accuracy, and long recognition time; while the grid power attenuation scheme has a small application range and is not suitable for non-grid equipment (such as battery-powered equipment) application

In the software industry, the zero-crossing comparison is generally used to obtain a square wave signal with the same period as the power frequency, and then the long-term counting and statistics average to obtain the power frequency frequency, and the scheme of setting parameters for the power frequency notch is obtained through this frequency lookup table. The power frequency acquisition accuracy is low, the update time is long, and the notch parameter adjustment error is large

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