The focus of this study is on the grid-forming operation of the Energy Router (ER) based on Model Predictive Control (MPC). ER is regarded as a key component of microgrids. It is a converter that interfaces the microgrid (s) with the utility grid. The ER has a multiport structure and bidirectional energy flow control. The ER concept can be implemented in Nearly Zero-Energy Buildings (NZEB) to provide flexible energy control. A concept is proposed where the ER works as a single grid-forming converter. The challenge is to keep the predefined reference voltage and frequency inside the NZEB in all possible modes, including the idle operation mode, current sources, and nonlinear load control. To gain stability and output voltage quality, the MPC is proposed. The design of the modified MPC algorithm with improved dynamics performance is explained. PLECS software is utilized to verify the proposed algorithm. The results demonstrate the suitable performance of the proposed control method in terms of total harmonic distortion of the output voltage. The influence of weighting coefficiencies is evaluated, showing the higher impact of the capacitor filter voltage on lowering the total harmonics distortion of the output voltage. Finally, the capability of the control system toward step change in the reference value is evaluated.

This study proposed an approach to dynamic wireless charging that uses a rotating receiver coil. Our simulation study focused on the verification of a novel way of increasing the coupling coefficient and power transfer stability by following the flux of the transmitting coils. To obtain the highest possible coupling by means of the FEM analysis, we studied the optimization of the trajectory of the angular velocity of the rotating receiver. The coupling coefficient trajectories that were obtained were simulated by means of the state space model with three transmitters. Our comprehensive analysis showed that the proposed approach of wireless power transmission enabled a 40% increase in the usage of track space.

It is shown that renewable energy sources (RES) are increasingly dominating the electricity market in many countries, while the amount of electricity generation by solar power plants (SPP) has been growing at a record pace in recent years. It is noted that although the share of RES continues to grow and the photovoltaic industry is developing rapidly, the industry still faces many challenges, in particular, how to continue to reduce the Levelized Cost of Energy (LCOE), improve the efficiency of operation and maintenance, and maintain the stability of the power grid, to ensure system security. The effective implementation of solar generation requires an analysis of the prospects for the development of local electric power systems that include SPP, the development of mechanisms and appropriate regulatory, methodological, technical and organizational support that will contribute to the effective development of solar generation, the construction of modern system (schematic) solutions. The analysis of the features of the development of green generation in Poland and Ukraine was carried out, the positive factors that influenced the development of renewable energy sources in Ukraine were determined, which made it possible to form the technical, economic and organizational conditions for the successful development of solar generation, in particular, information was provided on new players in developed energy markets according to the Fourth Energy EU package. The analysis showed that when increasing the efficiency of SPP systems, planning and demand management in the electric network, effective functioning of Energy Smart Community (ESC) become important. The basic components of the effective functioning of electric power systems with SPP are highlighted, namely: concepts of configurations of photovoltaic systems, Smart-inverters, Energy Storage System (ESS), formation of Virtual Power Plant (VPP) based on SPP. It is shown that each of the four concepts involves the connection of a series of photovoltaic panels or strings and power electronics devices (DC converters and inverters), which are configured taking into account the peculiarities of the functioning of various structural (schematic) solutions. The advantages of using Smart-inverters as a new technology that can help integrate solar energy and other distributed energy resources into the electrical network are evaluated. Smart inverters are used to help the electrical grid cope with intermittent generation, helping the electrical grid remain stable and maintain voltage and frequency requirements. It was determined that in any photovoltaic system, the ESS itself becomes a central component that significantly affects the cost, maintenance requirements, reliability and design of the SPP, and the important parameters of the ESS that affect the operation and performance of the photovoltaic system are the battery maintenance requirements, battery life, available power and efficiency. Trends in the market of advanced energy storage systems for SPPs for the next decade are presented. The functioning of virtual power plants based on SPP, as a network of aggregated distributed energy resources that are remotely connected and work together with flexible electricity consumers, is aimed at maximizing the benefits of participants. The possibilities and trends of SPP development in the near future, which are based on the research of Huawei, are presented.

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load’s terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion (THD) of the generated load voltage. The third variant of modulation concerns maximizing the voltage transfer ratio, minimizing the number of switching, and the common-mode voltage cancellation. The discussed modulations are based on the concept of sinusoidal voltage quadrature signals, which can be an effective alternative to the classic space-vector approach. In the proposed approach, the geometrical arrangement of basic vectors needed to synthesize output voltages is built from the less number of vectors, which is equal to the number of the matrix converter’s terminals. The PWM duty cycle computation is performed using only a second-order determinant of the voltages coordinate matrix without using trigonometric functions. A new approach to the PWM duty cycles computing and the load voltage synthesis by 5 × 5 and 12 × 12 topologies has been verified using the PSIM simulation software.

The main aim of this article is estimation of the heating energy demand and annual heating costs for classical sacral building equipped with ground source heat pump or gas boiler. For this purposes a simulation model in the Matlab Simulink 2022b has been developed. Heat losses through the...

In this paper, different Pulse Width Modulation (PWM) strategies for operating with a low-switching frequency, a topology that combines Conventional Matrix Converters (CMCs), and Coupled Reactors (CRs) are presented and discussed. The principles of the proposed strategies are first discussed by a conceptual analysis and later validated by simulation. The paper shows how the combination of CMCs and CRs could be of special interest for sharing the current among these converters’ modules, being possible to scale this solution to be a modular system. Therefore, the use of coupled reactors allows one to implement phase shifters that give the solution the ability to generate a stair-case load voltage with the desired power quality even the matrix converters are operated with a low-switching frequency close to the grid frequency. The papers also address how the volume and weight of the coupled reactors decrease with the growth of the fundamental output frequency, making this solution especially appropriate for high power applications that are supplied at high AC frequencies (for example, in airport terminals, where a supply of 400 Hz is required).