Static energy meters can be forced to give misreadings due to conducted electromagnetic interference (EMI). In previous research cases lower and higher readings of static energy meters were observed. In this paper an overview of previously reported lab experiments is given and further analyzed. The various situations are showing errors in the energy readings with respect to a reference meter. Based on these findings measurements are done using a dimmer in combination with a series of compact fluorescent lightning (CFL) and light emitting diode (LED) lamps. This setup was powered using a non-distorted mains power supply created by a four-quadrant amplifier combined with a line impedance stabilization network (LISN) to create a stable line impedance. The setup creates a pulsed current waveform with a short rise time. By using various line inductances the slope of the pulse is lowered and a correlation between the inclination of the slope and the deviations of the static meters is shown.

This article presents a time-domain waveform model developed to characterize pulsed, nonlinear, current waveforms resulting in electromagnetic interference on static energy meters. The waveform model is calculated by fitting the sampled waveform data into a linear piece-wise function through a process that involves applying algorithms of pulse extraction, change-point detection, and redundancy elimination. The model is applied to data from laboratory experiments that have indicated critical current waveforms resulting in electromagnetic interference problems with static meters. Afterwards, the parameters of the modeled waveforms are calculated in order to correlate them to metering errors. The most relevant parameters that are correlated to significant errors are the maximum slope, crest factor, pulse duration, and charge. The waveform model provides an accurate description of the complex nonlinear waveforms through simplified analytical expressions that reproduce the significant features of the interfering waveforms. This waveform modeling approach could be used to standardize the artificial test signals that are representative of realistic devices and scenarios.

Readings of static energy meters can be affected by conducted electromagnetic interference (EMI). Previous research reported many cases where lower and higher readings of static energy meters were observed. In this paper experiments with a water pump, controlled by speed regulators, resulted in huge errors in energy readings of static meters with respect to a reference meter. The speed regulators are intended to be used in conjunction with such water pumps. The tests were performed using a non-distorted mains power supply created by a fourquadrant amplifier with an internal impedance in accordance with the standards. The deviations observed are between-91% and +175% compared to the reference meter. The current waveforms attributed to these large deviations show large spikes with rise times of a few microseconds.

Conducted electromagnetic interference has shown to result in misreadings of static energy meters due to non-linear current waveforms. Based on these findings it is of interest to survey waveforms that occur in typical low voltage distribution networks, and to which static energy meters are exposed to. Therefore, complex waveforms in a domestic photovoltaic installation are identified. Furthermore, discrepancies between the generated power, consumed power by the loads and drawn power from the grid are found. This paper aims to correlate these waveforms to the observed discrepancies in the power consumption data and survey the waveforms that occur in these modern installations.

Testing of electrical and electronic equipment is generally performed using frequency domain tests like the IEC 61000-4-19. This standard covers the immunity to conducted, differential mode disturbances and signaling in the frequency range from 2 kHz to 150 kHz. Previous research describes several electromagnetic interference (EMI) cases in this frequency range, which cover pulsed, fast changing, current waveforms. For example cases are described where static energy meters can give misreadings when loaded with pulsed currents. Fast changing time domain signals are not covered by the standards. In this paper it is shown that the current frequency domain tests are not sufficient to determine the equipment's immunity, because of for instance non-linear effects, including saturation, digital sampling error effects and other non linear time invariant (LTI) effects.

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For the assessment of radiated electromagnetic interference (EMI) emission of an equipment under test (EUT) traditionally a limited amount of positions around the EUT are chosen. This is due to the long measurement time per position of the EMI test receiver, although the introduction of time domain electromagnetic interference (TDEMI) analyzers already created serious reduction in measurement time. The limited amount of measurement positions around an EUT means however that the maximum interference can be missed at certain positions around the EUT, creating an underestimation of the maximum emission. With the use of a low cost baseband digitizer this paper realizes a continuous positional measurement around an EUT. This measurement presents the maximum emission of the interference by considering every position around the EUT.

The increased use of non-linear appliances in households has resulted in several conducted electromagnetic interference issues, such as misreadings of static energy meters used for billing purposes of the households' energy consumption. In this paper a case is presented where a static energy meter indicates a power generation, while power is actually being consumed. A perceived power generation of more than 430 W is measured by a static energy meter installed in a household when a television with a commercial off the shelf remote controlled switch with dimming functionalities consumed 21 W. The same situation is reproduced in a controlled lab environment, to eliminate possible influences of other appliances in the grid, which confirmed the on-site results. The current waveforms causing this supposed generation of power are investigated and it is observed that the phase firing angle of the current pulse drawn by the load in combination with the commercial off the shelf remote controlled switch affects the metering errors and determines whether the errors indicate a false generation, a too high consumption of power, or no error at all. A combination of the household equipment and a basic unloaded switched mode power supply in conjunction with two remote controlled switches resulted in a perceived power generation of more than 600 W. Having these loads connected for the entire day would counteract the total consumption of an average household and could even "generate" energy, and thus generate money for the consumer.