EMC Testing of Electricity Meters Using Real-World and Artificial Current Waveforms

Abstract

In 2015, the energy measurement of some static electricity meters was found to be sensitive to specific conducted electromagnetic disturbances with very fast current changes caused by highly nonlinear loads, leading to meter errors up to several hundred percent. This article describes new results on the electromagnetic compatibility (EMC) of 16 different meters from all over Europe when exposed to real-world disturbance signals. Those test signals were obtained from household appliances and onsite measurements at metered supply points all over Europe. The results show that also the interference signals recorded onsite can cause measurement errors as large as several hundred percent, even for meters that pass the present EMC standards. This unambiguously demonstrates that the present immunity testing standards do not cover the most disturbing conducted interference occurring in present daily-life situations due to the increased use of nonlinear electronics. Furthermore, to enable the adoption of potential new test waveforms in future standards for electricity meter testing, artificial test waveforms were constructed based on real-world waveforms using a piece-wise linear model. These artificial test waveforms were demonstrated to cause meter errors similar to those caused by the original real-life waveforms they are representing, showing that they are suitable candidates for use in improved standardization of electricity meter testing.

Testing of DC Electricity Meters with Broadband Conducted Electromagnetic Disturbances

“…1. The principle of operation of the new DC testbed is similar to that of an arbitrary-waveform testbed for AC electricity meters with broadband conducted electromagnetic disturbances originally presented in [21] and further optimized and exploited in [19]. The latter AC testbed also simultaneously generates and measures high-speed arbitrary waveforms representing highly distorted real-world signals.…”

“…978-1-6654-1639-9/22/$31.00 ©2022 150 kHz [15] have led to new requirements and standardized test methods for electricity meters [16] and related measurement techniques for electromagnetic compatibility [17]. Furthermore, in the recent past, the energy readings of some static electricity meters were shown to be sensitive to specific broadband conducted disturbances beyond these new requirements [18] and corresponding new test waveforms and methods have been suggested for incorporation into improved testing standards just recently [19].…”

“…These distortions include broadband signals with frequency content up to 150 kHz and cover a wide range of applications such as high-current EV charging. The operating principle of the new DC testbed will be similar to that of an arbitrarywaveform AC electricity meter testbench originally developed and demonstrated in [21] and further optimized and utilized in [19]. Characterization of the components of the new DC testbed is described, as well as initial verification measurements for the setup as a whole.…”

Electromagnetic interference on static energy meters due to residential emissions

“…For that purpose, the interference on static energy meters resulting from the original and modelled waveform are tested on a test-bed, that is described in more detail in [103]. Therefore, the original waveforms that are representative for the set of interfering waveforms, as visualized in Figure 5.1, are tested as well as its modelled waveforms representations in Figure 5.3.…”

“…In order to validate the wavelet-based representation, it is tested experimentally on the same testbed as was used in the previous section, and is described in more detail in [103]. This is done by verifying that the reconstructed waveforms can effectively reproduce the same level of static energy meter error as the original ones, i.e.…”