Small-signal filtering algorithm used for wide-range energy meter

Abstract

The invention discloses a small-signal filtering algorithm used for a wide-range energy meter, which aims at a working mode of a metering management main control unit (MCU) and a metering chip. The small-signal filtering algorithm comprises the following steps: (1) reading each piece of electricity parameter data from the metering chip at the fixed time interval by the metering management MCU; (2) judging whether an electricity parameter input signal is less than a small-signal judgment threshold value, and if yes, filtering the electricity parameter data by the following algorithm. Extremelysmall metering management MCU resource is occupied by the algorithm disclosed by the invention; all basic electricity parameter signals which are input to the metering management MCU from the metering chip are dynamically filtered; and the process of filtering can be dynamically implemented according to the small-signal vibration characteristic tendency. The small-signal filtering algorithm also can comprise a step of automatically regulating a filtering coefficient, and a filtering result is quickly followed up when the signal is quickly changed so as to ensure that the response sensitivity is prior. When a signal tends to be stable and fluctuates nearby a certain fixed numerical value, data stability is guaranteed to be prior.

Description

technical field [0001] The invention relates to the field of electric energy metering, in particular to a small-signal filtering algorithm used in wide-range electric energy meters. Background technique [0002] With the full development of the national smart grid construction, more and more household users have switched to fully electronic smart meters. At present, most electronic smart meters use the working mode of metering chip + metering management MCU, and the metering chip collects electrical parameters. The signal, after internal processing and calculation, outputs the result to the metering management MCU. In order to ensure the stability and effectiveness of the collected signal, the traditional way to eliminate the interference signal is often to add a filter network to the front-end hardware circuit of the metering chip, and filter the sampled signal through a digital filtering algorithm inside the metering chip, but the input When the signal is very weak, facto...

AI Technical Summary

Problems solved by technology

In order to ensure the stability and effectiveness of the collected signal, the traditional way to eliminate the interference signal is often to add a filter network to the front-end hardware circuit of the metering chip, and filter the sampled signal through a digital filtering algorithm inside the metering chip, but the input When the signal is very weak, factors such as A / D imbalance inside the metering chip, excessive interference between the voltage signal and current signal channel, and unstable reference of the metering chip itself will invalidate the traditional filtering method for eliminating interference, resulting in output The data to the metering management MCU is unstable and the metering accuracy is low

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