Design of a multi-level inverter for solar power systems with a variable number of levels technique

Overall harmonic distortion and losses will grow during an energy conversion process, while power stability will be reduced. Multilevel inverter technologies have recently become very popular as low-cost alternatives for a variety of industrial purposes. The design's minimal benefits include reduced component losses, decreased switching and conduction losses, along with enhanced output voltage and current waveforms. Also, a reduction of the harmonic components of the current and output voltage of the inverter are the most important requirements in multilevel inverters. A seven-level inverter design is presented in this paper that is simulated using MATLAB/Simulink. The inverter converts the DC voltage from three photovoltaic (PV) systems into AC voltage at seven levels. During an outage of one of the PV systems, the inverter will make a switching reduction and supply the AC voltage as a five-level inverter. The inverter’s total harmonic distortion (THD) when it performs as a five-level or seven-level inverter is 4.19% or 1.13% respectively. The modulation technique used is phase disposition via six carriers and a single reference signal at the fundamental frequency. © 2023, Institute of Advanced Engineering and Science. All rights reserved.Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2022-0031Funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged: Grant Number FEUZ-2022-0031

Numerical investigation of alpha Stirling engine performance based on ideal and actual adiabatic analysis

This article discusses in detail the adiabatic models investigations of alpha Stirling engine with study the influence of performance factors; adiabatic analysis is a crucially effective method because it is close to the real and practical engines when compared to isothermal analysis. The numerical model was created using MATLAB software, an extremely useful tool for solving equations. The study includes two adiabatic analysis models: the ideal model, which considers heat transfer is the duty of the heater and cooler when the regenerator is ideal, and the simple model, which considers the loss and the transfer of heat between the regenerator matrix and the working fluid. © Published under licence by IOP Publishing Ltd

Analysis of Technical Efficiency, Economic Feasibility, and Environmental Impacts of using Solar Heating Installations for Buildings

This study aims to provide a clear vision of the potential of solar heating installations currently available in the market as a successful alternative to traditional methods, economic feasibility, and contribution to reducing greenhouse gas emissions. The study involves using solar energy to provide the energy needed to heat a house in Warsaw. The solar installations were tested, and their performance was simulated and compared based on production quantity with cost and suitability for the climatic conditions of the study area. In addition to determining the best way to install solar panels by calculating optimal tilt and azimuth angles. The work methodology for designing a suitable solar system went in two directions; the first is using a solar thermal collector in direct heat generation, while the second is using photovoltaic panels to generate electricity to heat water by a water heater. All results were obtained through simulation work in RETScreen and PVGIS software. The results showed that solar thermal collectors and photovoltaic panels contributed to the annual energy demand by 40% and 43%, and the financial returns in case the conventional energy is electricity or natural gas are 715 and 252 EUR (for STC) and 765 and 269 EUR (for PV), respectively. It also reduced annual emissions by 2.36 and 2.53 tCO2. © 2023, International Journal of Renewable Energy Research. All Rights Reserved.Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2022-0031Funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged: Grant Number FEUZ-2022-0031

Experimental Study of New Design for Orthogonal and Pelton Turbines Using a 3D Printer

В последние годы технология гидроэлектроэнергетики Пико получила значительное развитие. В настоящее время эта технология интегрируется в автономные системы в сельских регионах, которые не имеют доступа к электричеству. Данная работа посвящена лабораторному эксперименту с турбиной Пелтона и ортогональной турбиной. Исследована максимальная производительность, проанализированы эксплуатационные характеристики турбин. Настройка принтера выполнена с помощью программы Cura Ultimaker., в которой используется технология послойного осаждения (FDM - моделирование наплавленного осаждения). Результаты эксперимента показали, что при благоприятных условиях турбина Пелтона показала максимальную производительность.In recent years, Pico hydroelectricity has greatly developed, and its technology is now being integrated into an off- grid more so in the rural regions which do not have access to electricity. This paper is about a laboratory experiment designed and manufactured for both Pelton and orthogonal turbines, to measure the highest performance for rotation, also operational performance characteristic of has been dissected. The printer turbines are done by using Cura Ultimaker program. Where used of layer- by- layer deposition technology (FDM - Fused Deposition Modeling). The results from the experiment indicated that under the best working conditions, the Pelton turbine showed the highest performance