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Topic Review
Hydro Generation Scheduling
The optimal generation scheduling (OGS) of hydropower units holds an important position in electric power systems, which is significantly investigated as a research issue. Hydropower has a slight social and ecological effect when compared with other types of sustainable power source. The target of long-, mid-, and short-term hydro scheduling (LMSTHS) is to optimize the power generation schedule of the accessible hydropower units, which generate maximum energy by utilizing the available potential during a specific period. Numerous traditional optimization procedures are first presented for making a solution to the LMSTHS problem. Lately, various optimization approaches, which have been assigned as a procedure based on experiences, have been executed to get the optimal solution of the generation scheduling of hydro systems. This article offers a complete survey of the implementation of various methods to get the OGS of hydro systems by examining the executed methods from various perspectives. Optimal solutions obtained by a collection of meta-heuristic optimization methods for various experience cases are established, and the presented methods are compared according to the case study, limitation of parameters, optimization techniques, and consideration of the main goal. Previous studies are mostly focused on hydro scheduling that is based on a reservoir of hydropower plants. Future study aspects are also considered, which are presented as the key issue surrounding the LMSTHS problem.
  • 4.2K
  • 25 Jan 2022
Topic Review
Large-Scale Piezoelectric-Based Aircraft Systems
A new approach in the development of aircraft and aerospace industry is geared toward increas-ing use of electric systems. An electromechanical (EM) piezoelectric-based system is one of the po-tential technologies that can produce a compactable system with a fast response and a high power density. However, piezoelectric materials generate a small strain, of around 0.1–0.2% of the original actuator length, limiting their potential in large-scale applications.
  • 4.2K
  • 20 Feb 2021
Topic Review
Power Grid
One of the most critical infrastructures in the world is electrical power grids (EPGs). New threats affecting EPGs, and their different consequences, are analyzed in this survey along with different approaches that can be taken to prevent or minimize those consequences, thus improving EPG resilience. The necessity for electrical power systems to become resilient to such events is becoming compelling; indeed, it is important to understand the origins and consequences of faults. This survey provides an analysis of different types of faults and their respective causes, showing which ones are more reported in the literature. As a result of the analysis performed, it was possible to identify four clusters concerning mitigation approaches, as well as to correlate them with the four different states of the electrical power system resilience curve.
  • 4.2K
  • 23 Oct 2020
Topic Review
OBC Requirements and Applicable Standards
The OBC (on-board charger) is one of the interfacing parts of the EV (electric vehicle) that must interact with the external world via the connection to the utility grid or to dedicated electric vehicle supply equipment (EVSE) that is interfaced with the AC utility grid, ratings and requirements of which are beyond the control of manufacturers. For this reason, any vehicle occupying a built-in charger supposed follow certain regulations to be allowed in the market.
  • 4.2K
  • 15 Oct 2023
Topic Review
Medical Robots
The combination of artificial intelligence technology and medical science has inspired the emergence of medical robots with novel functions that use new materials and have a neoteric appearance. 
  • 4.1K
  • 02 Jun 2021
Topic Review
Applications of Substrate-Integrated Waveguide
Substrate-integrated waveguide (SIW) is a modern day (21st century) transmission line that has recently been developed. This technology has introduced new possibilities to the design of efficient circuits and components operating in the radio frequency (RF) and microwave frequency spectrum. Microstrip components are very good for low frequency applications but are ineffective at extreme frequencies, and involve rigorous fabrication concessions in the implementation of RF, microwave, and millimeter-wave components. This is due to wavelengths being short at higher frequencies. Waveguide devices, on the other hand, are ideal for higher frequency systems, but are very costly, hard to fabricate, and challenging to integrate with planar components in the neighborhood. SIW connects the gap that existed between conventional air-filled rectangular waveguide and planar transmission line technologies including the microstrip.
  • 4.1K
  • 13 Apr 2022
Topic Review
Modular Multilevel Converter Submodules
Voltage-source converter (VSC) HVDC systems based on modular multilevel converters (MMCs) combine the system advantages of fast and independent active and reactive power control, passive network supply, black start capabilities, frequency support and power oscillation damping with power electronics benefits such as scalable design, increased reliability, lower conversion losses and reduced filtering requirements, thus offering a commercially competitive solution. The structure of the SM is an important element of the MMC. This has been the case, where substantial SM topologies have been presented, specifically aimed at extending the functionalities of the MMC, in many cases aligned with niche applications of the converter rather than generic use as a VSC converter.
  • 4.1K
  • 18 Mar 2022
Topic Review
Cybersecurity of Battery Management System
Battery management systems (BMSs) are critical to ensure the efficiency and safety of high-power battery energy storage systems (BESSs) in vehicular and stationary applications. The proliferation of battery big data and cloud computing advancements has led to the development of a new generation of BMSs, named Cloud BMS (CBMS), aiming to improve the performance and safety of BESSs. The CBMS is a cyber-physical system with connectivity between the physical BMS and a cloud-based virtual BMS, which is realized through a communication channel such as Internet of Things. Compared to the traditional BMS, the CBMS offers significantly higher computational resources, leveraging the implementation of advanced digital twin models and best-in-class algorithms in the BMS software, which will provide superior performances.
  • 4.1K
  • 03 Aug 2023
Topic Review
Beam Steering Characteristics of Reconfigurable Transmitarray Antennas
The high gain beam steering antennas are widely used in 5G wireless mobile communications, radio frequency (RF) wireless power transmission, and satellite communications. In order to obtain high gain and beam steering characteristics, traditionally, antennas of the same type as phased array antennas, reflectarray antennas, and parabolic antennas have been designed. The transmitarray (TA) has attracted more and more interest from researchers due to its low profile, affordable cost, lower losses, low design complexity, and ease of fabrication. These have become popular solutions due to their remarkable applications, for instance, in biomedical systems (Brain and Breast Cancer Detection), civil and military radar systems, imaging systems, satellite communications, direct broadcasting services, and 6G/5G communication systems, etc.
  • 4.1K
  • 03 Mar 2022
Topic Review
Step-Down Partial Power DC-DC Converters
Photovoltaic (PV) systems made-up by two-stages of energy conversion are attractive from the operation point view. It is because the MPPT range is extended, due to the voltage decoupling between the PV system and the dc-link. Nevertheless, the additional conversion stage increases the volume, cost and power converter losses. Therefore, in large-scale PV systems formed by series connection of PV modules, most of commercial inverters are based on a single-stage system. The concept of partial power converters (PPC), previously implemented as a step-up stage, has not fully covered all PV applications. In this work, a PPC performing step-down operation is proposed and analyzed for a PV string application. This concept is actually interesting from the industry point of view, since with the new isolation standards of PV modules reaching 1500V, larger strings are currently starting to become popular. Since grid connection remains below 690V, larger strings impose more demanding operation for single-stage central inverters (required to operate at lower modulation indexes and demand higher blocking voltage devices). 
  • 4.0K
  • 01 Nov 2020
Topic Review
Microgrid Control
Microgrids (MGs) are advancing in terms of intelligence, distribution, and flexibility. Electrical grids are being dominated by cutting-edge power electronics and artificial intelligence (AI) techniques, and this trend may continue for many years to come.
  • 4.0K
  • 21 Feb 2023
Topic Review
Multiple-Output DC–DC Converters
Multiple-output DC–DC converters are essential in a multitude of applications where different DC output voltages are required. The interest and importance of this type of multiport configuration is also reflected in that many electronics manufacturers currently develop integrated solutions. Traditionally, the different output voltages required are obtained by means of a transformer with several windings, which are in addition to providing electrical isolation. However, the current trend in the development of multiple-output DC–DC converters follows general aspects, such as low losses, high-power density, and high efficiency, as well as the development of new architectures and control strategies.
  • 3.9K
  • 27 Apr 2022
Topic Review
List of Railway Electrification Systems
This is a list of the power supply systems that are, or have been, used for tramway and railway electrification systems. Note that the voltages are nominal and vary depending on load and distance from the substation. Many modern trams and trains use on-board solid-state electronics to convert these supplies to run three-phase AC induction motors. Tram electrification systems are listed here.
  • 3.9K
  • 27 Nov 2022
Topic Review
Variable Speed Diesel Generators
Variable Speed Diesel Generators (VSDGs)  is a solution to optimize engine consumption and increase system efficiency during different regimes. It improves system behavior by adapting diesel generators (DGs) speed with demanded mechanical load from the generator. VSDG improves efficiency, increases engine lifetime, reduces fuel consumption, and GHG emissions. Conventional fixed speed DG can rarely operate at less than 50% of the maximal load, while VSDGs can operate for a long period at low rotational speed to support lower loads.
  • 3.9K
  • 19 Jan 2022
Topic Review
Current Sensing Methods in Power Electronics Applications
A current sensor is a device exploited to measure electric currents, either alternating current (AC) or direct current (DC). These devices are used in various applications, including detecting faults, monitoring performance (for control or prognostics), and detecting changes in system behavior. Power applications employ various current-monitoring products to control, characterize, and monitor the current flow. Current sensors, for example, are used in power lines to measure the flow of the current, for controlling current flow, or detect overcurrent or excess currents.
  • 3.9K
  • 10 Aug 2023
Topic Review
H Bridge
An H bridge is an electronic circuit that switches the polarity of a voltage applied to a load. These circuits are often used in robotics and other applications to allow DC motors to run forwards or backwards. Most DC-to-AC converters (power inverters), most AC/AC converters, the DC-to-DC push–pull converter, most motor controllers, and many other kinds of power electronics use H bridges. In particular, a bipolar stepper motor is almost invariably driven by a motor controller containing two H bridges.
  • 3.9K
  • 24 Oct 2022
Topic Review
Load Forecasting Models in Smart Grid
The smart grid concept is introduced to accelerate operational efficiency and enhance the reliability and sustainability of the power supply. The load forecasting technique involves estimating future loads using historical and present data. In a smart grid, the forecasting of loads is done by considering the power consumption by users and the power produced by all types of generations (renewable and non-renewable) with the help of smart energy meters.
  • 3.8K
  • 24 Feb 2023
Topic Review
Plug-in Electric Vehicles in Germany
The adoption of plug-in electric vehicles in Germany is actively supported by the German Federal Government. Under its National Plattform for Electric Mobility, Chancellor Angela Merkel set an initial goal in 2010 to deploy one million electric vehicles on German roads by 2020. Initially, the government did not provide subsidies to promote sales of plug-in electric vehicles, however, by the end of 2014 it was recognized that the country was well behind the set sales targets. A purchase bonus scheme was approved in 2016, but premium cars were not eligible to the incentive. In order to meet the climate targets for the transport sector, in 2016 the government set the goal to have from 7 to 10 million plug-in electric cars on the road by 2030, and 1 million charging points deployed by 2030. In June 2020, and as a result of the economic impact of the COVID-19 pandemic, the government approved a recovery plan which included €8 billion to promote electric vehicle adoption and deployment of charging infrastructure. The purchase bonus for all-electric cars was raised temporarily from €6,000 to €9,000 for cars costing less than €40,000. There are lower bonuses for the purchase of plug-in hybrids, used cars and for leasing. The additional bonus will be available until the end of 2025. The initial one million goal was achieved in July 2021. The stock of plug-in electric vehicles in Germany is the largest in Europe, and (As of July 2021), there were 1 million plug-in electric vehicles on the road, including buses and commercial vehicles. The German fleet in use consists of 54% all-electric vehicles and 46% plug-in hybrids. (As of December 2019), Germany had a stock of 21,890 light-duty electric commercial vehicles, the second largest in Europe after France. (As of March 2020), the country had 27,730 public charging stations. The plug-in electric car segment market share was 1.58% in 2017 and 1.9% in 2018. The segment market share rose to 3.10% in 2019, and despite the global strong decline in car sales brought by the COVID-19 pandemic, the uptake rate achieved a record 13.6% in 2020. (As of January 2021), the stock of German plug-in electric cars on the road totaled 588,944 units, representing 1.2% of all registered passenger cars, up from 0.5% the previous year. In 2019, Germany surpassed Norway as Europe's top selling country market in terms of annual sales, and with a record volume of 394,632 plug-in passenger cars registered in 2020, up 263% from 2019, Germany listed for a second year running as the best selling European plug-in market. Both years, the German market led both the fully electric and plug-in hybrid segments. The only country that outsold Germany in 2020 was China.
  • 3.8K
  • 10 Oct 2022
Topic Review
Grid Connected Photovoltaic Inverters
       The installation of photovoltaic (PV) system for electrical power generation has gained a substantial interest in the power system for clean and green energy. However, having the intermittent characteristics of photovoltaic, its integration with the power system may cause certain uncertainties (voltage fluctuations, harmonics in output waveforms, etc.) leading towards reliability and stability issues. In PV systems, the power electronics play a significant role in energy harvesting and the integration of grid-friendly power systems. Therefore, the reliability, efficiency, and cost-effectiveness of power converters are of main concern in the system design and are mainly dependent on the applied control strategy. 
  • 3.8K
  • 26 Aug 2020
Topic Review
Mobile Phone Overuse
Mobile phone overuse (smartphone addiction, mobile-phone addiction, problem mobile phone use, or mobile phone dependency) is a dependence syndrome seen among mobile phone users. Some mobile phone users exhibit problematic behaviors related to substance use disorders. These behaviors can include preoccupation with mobile communication, excessive money or time spent on mobile phones, use of mobile phones in socially or physically inappropriate situations such as driving an automobile. Increased use can also lead to increased time on mobile communication, adverse effects on relationships, and anxiety if separated from a mobile phone or sufficient signal.
  • 3.8K
  • 14 Nov 2022
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