The complex influence of external and internal electricity networks on the magnetic field level in residential premises of buildings

The problem of determining the complex influence of a group of electricity networks (external electricity networks, built-in transformer substations, cable electric heating systems, etc.) on the magnitude of the summary magnetic field (MF) in a residential premise of a building has not been sufficiently researched. This results in an overestimation of the assess the magnitude of the summary MF, generated by the group of electricity networks, as well as to the use of technical measures to reduce this MF, which have excessive efficiency and are accompanied by excessive expenses. The goal of the work is to investigate of the complex influence of external and internal electricity networks on the MF level in residential premises of buildings and definition of conditions, which provide the minimum necessary limitations on the MF flux density of individual electricity networks, at which the summary level of MF in residential premises, does not exceed the normative level of 0.5 μT. The methodology of determining the complex influence of the group of electricity networks on the level of MF in residential premises is based on the Biot-Savart’s law and the principle of superposition and allows determining the functional dependence between the instantaneous values of currents in electricity networks, their geometrical and physical parameters, and the summary effective value of MF flux density in the premise. Scientific novelty. For the first time, the methodology for determining the complex influence of the group of external and internal electricity networks on the level of MF in residential premises is proposed. Practical significance. The implementation of the proposed methodology will allow to reduce the calculated coefficient of normalization of the MF of individual electricity networks by 25–50 %, which, in turn, will contribute to the reduction of economic costs for engineering means of normalizing the summary MF in residential premises, caused by the influence of the group of electricity networks. References 56, tables 4, figures 8.