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The importance of MMF space harmonics in squirrel-cage induction motors has been recognized in the literature since the beginning. Their details have been analyzed over the years, but only partly systematized. In this article, however, not only the origin and the entire system of that harmonics are described, but also their interaction causing the asynchronous…

With the spread of inverters, the attention of designers naturally turned to 5-phase motors, due to their advantageous properties. In this regard, perhaps the most important issue in the design of such machines is the selection of the correct rotor slot number. Many articles have been published on multiphase machines, however, only few of them…

Skewing of the rotor slot of a squirrel-cage induction machine has been commonly used since the beginning. However, little guidance is given regarding the principle of the working effect of the method, but even in such rare cases, the explanation does not cover the true physical reality. Consequently no formula exists for calculation of the…

Extemporaneous omeprazole-based preparations are commonly used in hospitals; however, there are no validated studies about physicochemical stability. This study aimed to determine if temperature, luminosity, and the type of diluent affect the stability of omeprazole in the extemporaneous preparation. For stability, the methodology validated previously by our group was used. The 2k experimental design included…

This study addresses the need for improved prognostics in switch-mode power supplies (SMPS) that incorporate electromagnetic interference (EMI) filters, with a focus on aluminum electrolytic capacitors, which are critical for the reliability of these systems. The primary aim is to develop a robust model-based approach that can accurately predict the degradation and operational lifetime of…

Forecasting solar PV power output holds significant importance in the realm of energy management, particularly due to the intermittent nature of solar irradiation. Currently, most forecasting studies employ statistical methods. However, deep learning models have the potential for better forecasting. This study utilises Long Short-Term Memory (LSTM), Gate Recurrent Unit (GRU) and hybrid LSTM-GRU deep…

The solar photovoltaic (PV) power generation industry has experienced substantial, ongoing growth over the past decades as a clean, cost-effective energy source. As electric grids use ever-larger proportions of solar PV, the technology’s inherent variability—primarily due to clouds—poses a challenge to maintaining grid stability. This is especially true for geographically dense, electrically isolated grids common…

The integration of distributed energy resources has ushered in a host of complex challenges, significantly impacting power quality in distribution networks. This work studies these challenges, exploring issues such as voltage fluctuations and escalating power losses caused by the integration of solar systems and electric vehicle (EV) chargers. We present a robust methodology focused on…

This paper presents mathematical model of a wind turbine simulator based five-phase permanent magnet generator supplying nonlinear load. The mathematical model of wind turbine characteristics together with available tool blocks of the five-phase permanent generator and semiconductor devices of an AC-DC converter formed as a nonlinear load is implemented on MATLAB /Simulink to investigate the…

The integration of fluctuating renewable resources such as wind and solar into existing power systems poses challenges to grid reliability and the seamless incorporation of these resources. To address the inherent variability in renewable generation, direct load control emerges as a promising method for demand-side management. Thermostatically controlled appliances, like air conditioners, hold a significant…

In this paper, we delve into the pressing necessity for proficient battery cell balancing, an imperative in the context of the escalating adoption of renewable energy and electric vehicles. While traditional methodologies, including the passive technique, offer a straightforward and cost-effective solution, they compromise on efficiency. The active technique, though superior in efficiency, is hindered…

Condition assessment of medium voltage assets is essential to ensure reliability and cost-effective operation of power distribution networks. This article presents a literature review of condition assessment of medium voltage assets related to a distribution system in a non-interconnected zone in Colombia, namely, power transformers, photovoltaic systems, switchgear, lines and cables, and instrument transformers. Advanced…

The increase electricity production based on renewable energies sources responds to the requirements of sustainable development. In recent years, the investment in the wind energy sector has increased to satisfy green electricity generation and environment protection. Wind energy is currently the most competitive energy resource that is part of the world’s countries views on the…

The levelized cost of electricity production is highly dependent on the cost of fuel oil on the world market. In order to reduce the dependency on the fuel oil, many countries are adopting an energy transition towards distributed generation. Distributed generation can be described as various means of generating electricity at or near where it…

Due to the variations in weather conditions, photovoltaic systems adopt a technique based on maximum power point tracking to extract the maximal power of the solar module. In the literature, there are many different methods classical and intelligent of maximum power point tracking (MPPT). But, due to the semiconductor effect, the current-voltage characteristics of the…

Narrow-band Internet of Things (NB-IoT) is a low-power wide-area network (LPWAN) method that was first launched by the 3rd generation partnership project (3GPP) Rel-13 with the purpose of enabling low-cost, low-power, and wide-area cellular connections for the Internet of Things (IoT). As the demand for over-the-air services grows and with the number of linked wireless…

In this study, we conducted an experimental study and efficiency optimization of the outer rotor (hub) BLDC (brushless direct current) motor and axial BLDC motor for light electric vehicles. Both motors were investigated in the simulation environment and experimentally. The axial flux BLDC motor had a rated power of 10 KW, and a rated speed…

The quality of the electric power system must be maintained properly, one of which is voltage. Under certain operating conditions, the bus voltage may drop below its minimum level, called bad voltage. A large reactive load can cause a voltage drop across the bus or the location of the bus is far from the generator…

In this research paper, a technical and economic-environmental study was developed to investigate the possibility of establishing various hybrid power systems with different operation modes. Grid-connected and standalone hybrid systems (solar-wind with storage batteries and diesel generators) have been realized in order to carry out a comparative analysis study of two configurations. These systems have…

Many millions of people have adverse effects on their lives, both socially and economically, when a power outage occurs. Along with other electrical events, the lack of Situational Awareness (SA) is one of the root causes of power system outages. In order to promote adequate situational awareness, both power system and microgrid interfaces should communicate…

Power losses exist naturally and have to be cared for in the operation of electrical power systems. Many researchers have worked on various methods and approaches to reduce losses by incorporating distributed generators (DG), particularly from renewable sources. These studies are based on the maximum unit penetration of the DGs, which is rarely achieved, resulting…

Despite many factors conducive to renewable energy investment in Qatar (e.g., the fact that the state is a major gas exporter whose long-term prosperity depends on economic diversification), there is very low uptake of solar panel adoption among home and business owners. Major challenges implicitly face the deployment of solar and other renewables in Qatar,…

Recently, many problems have been caused by battery fires. The existing BMS(Battery Managment System) measured the voltage of each cell of the battery through the physical connection between the battery and the control module. However, if a battery with up to 1000 VDC becomes inoperable due to an external factor, the battery is damaged, and…

This communication proposes a grounded immittance function simulator that, depending on the proper choice of the passive components, can simulate parallel-type impedances of the R-L, R-C, and L-C forms. Only two grounded passive components and two voltage differencing buffered amplifiers (VDBAs) are used to implement the suggested circuit. All three simulated equivalent elements, namely Req,…

The relevance of static synchronous compensator (STATCOM) controllers in controlling power network parameters is causing them to be included in contemporary networks. But for the intended objectives to be attained, the best device positioning and parameter settings are essential. This work compares the performance of the particle swarm optimization (PSO) and firefly algorithm (FA) in…