Assessment of Human Exposure (Including Interference to Implantable Devices) to Low-Frequency Electromagnetic Field in Modern Microgrids, Power Systems and Electric Transports

Abstract

Electromagnetic field emissions of modern power systems have increased in complexity if the many power conversion forms by means of power electronics and static converters are considered. In addition, the installed electric power has grown in many everyday applications such as wireless charging of vehicles, home integrated photovoltaic systems, high-performance electrified transportation systems, and so on. Attention must then be shifted to include harmonics and commutation components on one side, as well as closer interaction with humans, that concretizes in impact on physiological functions and interference to implantable medical devices and hearing aids. The panorama is complex in that standards and regulations have also increased significantly or underwent extensive revisions in the last 10 years or so. For assessment, the straightforward application of the limits of exposure is hindered by measurement problems (time or frequency domain methods, positioning errors, impact of uncertainty) and complex scenarios of exposure (multiple sources, large field gradient, time-varying emissions). This work considers thus both the clarification of the principles of interaction for each affected system (including humans) and the discussion of the large set of related normative and technical documents, deriving a picture of requirements and constraints. The methods of assessment are discussed in a metrological perspective using a range of examples.

Exploration on Signal Processing Performance of Wireless Sensor in Electromagnetic Interference Environment

“…Gauss's Law of Electric Flux. Gauss's law of electric flux describes that the electric flux generated through any closed surface in an EM equals the amount of charge surrounded by the surface [20]. Its differential form is calculated by…”

“…Equation (20) calculates the connection conditions when there is no free surface charge on the interface of different media:…”

The Effects of Supraharmonic Distortion in MV and LV AC Grids

“…Such negative effects can be seen as an extension of those attributed to harmonic distortion; they range from stress to dielectrics and insulating materials within cables, transformers, and capacitors, including the aging of filter components, to network resonance scenarios, and to various cases of interference, in particular to power line communication (PLC) devices. Another area of concern is human exposure to the electromagnetic field, including interference with implantable devices, as caused by high-frequency components such as SHs [ 13 ]. The topic is critical, being related to human health and safety; however, the magnetic field limit values identified by various standards and publications are always above a fraction of for non-critical effects and several for more serious consequences.…”

Receiver–Coil Location Detection in a Dynamic Wireless Power Transfer System for Electric Vehicle Charging

“…In addition, in the case of dynamic charging, with the transmitter coils being located slightly beneath the road/track level (the primary pads or resonators), the charging system is energized upon the vehicle arrival for a matter of economy, but also protection of pedestrians. In fact, the presence of the vehicle body prevents direct occupation of the pad area and partially shields the the emitted magnetic field [ 7 , 8 ].…”