Boguslaw Butrylo

The impulse nature of the ignition coils operation imposes specific requirements for the construction of high-voltage windings and magnetoguide. The properties of the system (e.g. pulse energy, inter-turn voltages, operating time) depend on the spatial arrangement of the secondary winding and the materials used. The article considers the properties of the system in which the use of additional magnets with selected remanence was taken into account. The method of modeling the impulse coil, the selection of the operating point with the use of magnets in order to shape the distribution of magnetic field and dynamics of currents and voltages in the system were discussed. The influence of the remanence of magnets on the dynamic characteristics of the current in the primary winding and the voltage in the secondary winding was considered

One of the key strategies for decarbonization and green transportation is using electric vehicles (EVs). However, challenges like limited charging infrastructure, EV battery characteristics, and grid integration complexities persist. This study proposes a mixed-integer linear programming (MILP) approach to optimize a grid-connected solar PV-based commercial EV charging station (SPEVCS) with a battery energy storage system (BESS) for profit maximization. The MILP model efficiently manages SPEVCS operations, considering solar power fluctuations, EV charging patterns, and BESS usage. By coordinating charging schedules, grid stability is reinforced, and excess solar power can be lucratively managed. Comparing grid-connected and off-grid SPEVCS scenarios highlights grid integration benefits. Solar power mismatches with optimal charging periods pose a challenge, addressed here by BESS utilization and import/export of deficit/surplus power from/to the grid. The proposed framework incorporates solar power forecasts and probabilistic EV arrival predictions, enhancing decision accuracy. This approach fosters viable commercial EV charging, promotes green transportation, and reinforces grid resilience.

Electric vehicles (EVs) will be dominating the modes of transport in the future. Current limitations discouraging the use of EVs are mainly due to the characteristics of the EV battery and lack of easy access to charging stations. Charging schedules of EVs are usually uncoordinated, whereas coordinated charging offers several advantages, including grid stability. For a solar photovoltaic (PV)-based charging station (CS), optimal utilization of solar power results in an increased revenue and efficient utilization of related equipment. The solar PV and the arrival of EVs for charging are both highly stochastic. This work considers the solar PV forecast and the probability of EV arrival to optimize the operation of an off-grid, solar PV-based commercial CS with a battery energy storage system (BESS) to realize maximum profit. BESS supports the sale of power when the solar PV generation is low and subsequently captures energy from the solar PV when the generation is high. Due to contrasting characteristics of the solar PV and EV charging pattern, strategies to maximize the profit are proposed. One such strategy is to optimally size the BESS to gain maximum profit. A mixed integer linear programming (MILP) method is used to determine the optimal solution.

In this paper, we present the method for determination of effective electromagnetic parameters of complex building materials. By application of the proposed algorithm, it is possible to analyze electromagnetic field distribution for large-scale problems with heterogeneous materials. The two-dimensional numerical model of building components (hollow brick) with periodic boundary conditions was solved using the finite-difference time-domain method (FDTD) and discussed. On this basis, the resultant transmission coefficient was found and then the equivalent relative permeability and electric conductivity of heterogeneous dielectric structures, in the developed homogenization algorithm, were identified. The homogenization of material properties was achieved by performing a multi-variant optimization scheme and finally, selecting optimal electric parameters. Despite the analysis of heterogeneous building materials, the presented algorithm is shown as a tool for the homogenization of complex structures when scattering of a high-frequency electromagnetic field is considered.

Equivalent values describing non-homogeneous material, calculated using the developed algorithm, can be used in modelling large-scale systems in the case when it is not possible to fully map the complex structure, which made of composite material (e.g. clinker bricks, concrete). The developed algorithm can be used to determine equivalent electric parameters of various complex structures taking into account different electric parameters and their range of single dielectric, size of holes/admixtures, frequency or the thickness of the layer through which the EM wave passes.

This paper deals with some aspects of formulation and implementation of a broadband algorithm with build-in analysis of some dispersive media. The construction of the finite element method (FEM) based on direct integration of Maxwell’s equations and solution of some additional convolution integrals is presented. The broadband, fractional model of permittivity is approximated by a set of some relaxation sub-models. The properties of the 3D time-dependent formulation of the FEM algorithm are determined using a benchmark problem with the Cole-Cole and the Davidson-Cole models. Several issues associated with the implementation and some constraints of the broadband finite element algorithm are presented.

The paper presents the developed algorithm of the finite difference frequency domain method (FDFD). The proposed formulation allows analyzing some large-scale models using a local refinement of the differential mesh based on the h-adaptation of the rectangular elements. The final form of the algorithm is implemented to estimate field phenomena connected with the propagation of high frequency electromagnetic waves in building constructions. The electrical losses in materials caused by conducting and displacement currents are taken into account. The presented algorithm is applied to analyze electromagnetic field around a pillar of a building, in the band of some local wireless communication systems. The results obtained from the proposed FDFD scheme are confronted with the field distribution computed using FDTD and FEM methods.