Modeling of DC energy meter modules and simulation analysis of error characteristics under dynamic load waveforms

In order to address the lack of a combined waveform mode model that reflects the characteristics of rapid changes in DC amplitude and the unclear impact of dynamic energy signal excitation on the dynamic error of DC energy meters, this paper adopts a mechanism modeling approach. Firstly, mathematical models are established for the signal preprocessing unit, signal conversion unit, and power and energy measurement unit of the DC energy meter. Secondly, a set of typical DC dynamic waveform modes is defined, and mathematical models for four typical examples are established, followed by the construction of a combination waveform mode dynamic energy test signal model. Then, the impact of the programmable gain amplifier (PGA), power filter, and energy accumulation unit on the dynamic error of the DC energy meter is analyzed through simulations using a dynamic energy test signal as the input. Finally, the dynamic errors in the energy meter caused by the PGA gain switching delay, filter length, and power threshold of the energy accumulation unit under dynamic energy test waveform excitation are analyzed. Our conclusions provide a theoretical basis for improving the dynamic error characteristics of energy meters.