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Topic Review
Grid-Forming Control Approaches
Changes are being implemented in the electrical power grid to accommodate the increased penetration of renewable energy sources interfaced with grid-connected inverters. The grid-forming (GFM) control paradigm of inverters in active power grids has emerged as a technique through which to tackle the effects of the diminishing dominance of synchronous generators (SGs) and is preferred to the grid-following (GFL) control for providing system control and stability in converter-dominated grids. 
  • 3.0K
  • 29 Dec 2023
Topic Review
Optical Sensors for Oil/Gas Applications
The sensing requirements of the Oil & Gas industry for improved sensing in deeper zones include increased transmission length, improved spatial coverage and integration of multiple sensors with multimodal sensing capability. This imposes problems like signal attenuation, crosstalks and cross sensitivities. Optical fibre-based sensors are expected to provide superior sensing capabilities compared to traditional electrical sensors. 
  • 2.9K
  • 26 Sep 2021
Topic Review
Topologies of T-Type Multilevel Inverters
Multilevel inverters (MLI) consist of a wide range of power converters. They have many designs and have been introduced with different circuit topologies such as neutral point clamped, diode clamped, cascaded H-bridges, and flying capacitors. Some of these MLIs have disadvantages, including design complexity, size, and losses due to the large number of switching devices required when they produce many output voltage levels. They are also bulky in size and may require several DC power sources. 
  • 2.9K
  • 24 May 2023
Topic Review
Single Event Upset
A single event upset (SEU) is a change of state caused by one single ionizing particle (ions, electrons, photons...) striking a sensitive node in a micro-electronic device, such as in a microprocessor, semiconductor memory, or power transistors. The state change is a result of the free charge created by ionization in or close to an important node of a logic element (e.g. memory "bit"). The error in device output or operation caused as a result of the strike is called an SEU or a soft error. The SEU itself is not considered permanently damaging to the transistor's or circuits' functionality unlike the case of single event latchup (SEL), single event gate rupture (SEGR), or single event burnout (SEB). These are all examples of a general class of radiation effects in electronic devices called single event effects (SEE).
  • 2.9K
  • 24 Oct 2022
Topic Review
Range Extender (Vehicle)
A range extender vehicle is a battery electric vehicle that includes an auxiliary power unit (APU) known as a 'range extender'. The range extender drives an electric generator which charges a battery which supplies the vehicle's electric motor with electricity. This arrangement is known as a series hybrid drivetrain. The most commonly used range extenders are internal combustion engines, but fuel-cells or other engine types can be used. Range extender vehicles are also referred to as extended-range electric vehicles (EREV), range-extended electric vehicles (REEV), and range-extended battery-electric vehicle (BEVx) by the California Air Resources Board (CARB). The key function of the range extender is to increase the vehicle's range. Range autonomy is one of the main barriers for the commercial success of electric vehicles, and extending the vehicle's range when the battery is depleted helps alleviate range anxiety. A range extending vehicle design can also reduce the consumption of the range extending fuel (such as gasoline) by using the primary fuel (such as battery power), while still maintaining the driving range of a single fuel vehicle powered by a range extending fuel such as gasoline. The range extending fuel is generally considered to be less environmentally and economically friendly to use than the primary fuel source, so the vehicle control system gives preference to using the primary fuel if it's available. However, due to range limitations with the primary fuel source, the range extending fuel allows the vehicle to get many of the cost and environmental benefits of the primary fuel, while maintaining the full driving range of the range extending fuel source. For example, in the Chevy Volt, battery power from the electric grid can be cheaper and more environmentally sustainable than burning gasoline (depending on the electric generation source), but due to the trade offs between the range of a pure electric vehicle and its battery size, adding the range extending gasoline is considered by many to be good compromise to give the Chevy Volt a significantly greater driving range. How many benefits are derived from using the primary fuel however depend on how the vehicles are driven. For example, a first generation Chevy Volt will operate 100% on battery power from the electric grid for the first 60 km (37 miles), while the second generation Volt will operate on 100% battery power for the first 85 km (53 miles) when fully recharged between trips. However, if the same Chevy Volt is driven for hundreds of miles a day it will require significant gasoline as the battery will be quickly depleted. Using the gasoline engine to generate power for the motors, the economy ratings are 6.4 L/100 km (37 mpg‑US) and 5.6 L/100 km (42 mpg‑US) for the different generation models. Therefore, it is critical to understand the driving patterns of the average commuter to fully understand the impact these range extending vehicles will have in the real world. Many range extender vehicles, including the Chevrolet Volt and the BMW i3, are able to charge their batteries from the grid as well as from the range extender, and therefore are a type of plug-in hybrid electric vehicle (PHEV). When a range extender uses conventional fuels they can re-fuel at regular fuel stations, which provides them with a similar driving range to conventional automobiles. As an REEV is only propelled by the electric motor it can do away with the weight and cost associated with the gearbox transmission system typically used in internal combustion engine cars. Further, as the range extender does not need to increase or decrease output in line with the power needs of the vehicle (this task is handled by the electric motor) the range extender can be sized to satisfy the vehicle's average power requirement rather than its peak power requirement (such as when accelerating). The range extender can also operate much closer to its most efficient rotational speed. These design features allow an REEV to convert fossil fuel energy to electric power and vehicle motion very efficiently.
  • 2.9K
  • 28 Oct 2022
Topic Review
Probabilistic Optimization Techniques in Smart Power System
Stochastic programming is used to solve optimization problems in which the majority of the parameters are probabilistic. Probabilistic optimization can make efficient use of information, both in terms of selecting evaluation points and the message they convey. It can handle many sorts of noise and adapts to various aspects of optimization issues. Unlike deterministic optimization, probabilistic optimization techniques discover the best solution for data with randomness.
  • 2.9K
  • 17 Feb 2022
Topic Review
Ultra-Low-Frequency Oscillation
One of the prominent problems faced with hydro-dominant power system is ultra-low-frequency oscillation (ULFO) with a frequency deviation of 0.1 Hz lower, which is caused by the negative damping of hydro generators. ULFO might lead to an oscillation of all generators with the same oscillation frequency, restricting consumption of hydropower renewable energy.
  • 2.9K
  • 27 Oct 2020
Topic Review
Wireless Battery Management System Topologies
An effective battery management system (BMS) is indispensable for any lithium-ion battery (LIB) powered systems such as electric vehicles (EVs) and stationary grid-tied energy storage systems. Massive wire harness, scalability issue, physical failure of wiring, and high implementation cost and weight are some of the major issues in conventional wired-BMS. One of the promising solutions researchers have come up with is the wireless BMS (WBMS) architecture. Despite research and development on WBMS getting momentum more than a decade ago, it is still in a preliminary stage. Significant further upgradation is required towards developing an industry-ready WBMS, especially for high-power LIB packs.
  • 2.9K
  • 22 Sep 2021
Topic Review
Control System Design for Collaborative Robots
Human–robot collaboration is an innovative area aiming to construct an environment for safe and efficient collaboration between humans and robots to accomplish a specific task. Collaborative robots cooperate with humans to assist them in undertaking simple-to-complex tasks in several fields, including industry, education, agriculture, healthcare services, security, and space exploration. These robots play a vital role in the revolution of Industry 4.0, which defines new standards of manufacturing and the organization of products in the industry. Incorporating collaborative robots in the workspace improves efficiency, but it also introduces several safety risks.
  • 2.9K
  • 30 Jan 2023
Topic Review
Plug-In Electric Vehicles in the United Kingdom
The adoption of plug-in electric vehicles in the United Kingdom is actively supported by the British government through the plug-in car and van grants schemes and other incentives. Around 455,000 light-duty plug-in electric vehicles had been registered in the UK up until February 2021, consisting of about 215,000 all-electric vehicles and 240,000 plug-in hybrids. Until 2019, the UK had the second largest European stock of light-duty plug-in vehicles in use after Norway.
  • 2.9K
  • 11 Nov 2022
Topic Review
IoT and the Energy Sector
Integration of renewable energy and optimization of energy use are key enablers of sustainable energy transitions and mitigating climate change. Modern technologies such the Internet of Things (IoT) offer a wide number of applications in the energy sector, i.e, in energy supply, transmission and distribution, and demand. IoT can be employed for improving energy efficiency, increasing the share of renewable energy, and reducing environmental impacts of the energy use.
  • 2.9K
  • 26 Sep 2021
Topic Review
Emergency Communication Networks
Emergency communication refers to the communication means and methods needed for the extensive use of various communication resources to support rescues, including emergency rescues, and the necessary communication in the case of natural or manufactured emergencies. Because of the characteristics of disasters, making effective use of limited resources to provide the best communication services is a key problem. Unlike the traditional communication network, the emergency communication network is a complex network, and enables the implementation of emergency rescue activities and provides the primary conditions for the realization of emergency rescue functions. Its network structure has a significant impact on rescue efficiency. In different emergency situations, the demand for emergency communication is different, and the technical means used are different. Emergency communication mainly has the following characteristics: uncertainty of time and place; uncertainty of capacity demand; high degree of timeliness of the emergency communication; complexity of the environment; uncertainty of the degree of damage to the communication network itself; and diversification of information.
  • 2.9K
  • 24 Mar 2023
Topic Review
Breakdown Voltages in Different Types of Gases
The idea of using a vacuum as an insulating medium is to take advantage of the fact that when the gas pressure is reduced to a value at which the average free paths of molecules and electrons are greater than the contact gap in the insulating system, the development of electron avalanches that initiate discharges in gases is impossible.
  • 2.8K
  • 07 Sep 2022
Topic Review
Distributed Element Circuit
Distributed element circuits are electrical circuits composed of lengths of transmission lines or other distributed components. These circuits perform the same functions as conventional circuits composed of passive components such as capacitors, inductors, and transformers. They are used mostly at microwave frequencies where conventional components are difficult or impossible to implement. A major advantage of distributed element circuits is that they can be produced cheaply as a printed circuit board for consumer products such as satellite television. They are also made in coaxial and waveguide formats for applications such as radar, satellite communication, and microwave links. A phenomenon that is much used in distributed element circuits is that a length of transmission line can be made to behave as a resonator. Distributed element components that do this include stubs, coupled lines, and cascaded lines. Circuits built from these components include filters, power dividers, directional couplers, and circulators. Distributed element circuits were investigated in the 1920s and 1930s but did not become important until World War II when they were used in radar. After the war their use was at first limited to military, space, and broadcasting infrastructure use but improvements in materials science in the field soon led to wider applications.
  • 2.8K
  • 17 Oct 2022
Topic Review
Multi-Motor Vehicular Systems
With vehicle electrification, autonomous driving, and employment of X-By-Wire technology, mechanical systems are replaced by motor drives improving their efficiency and performance. Thus, vehicular systems are becoming multi-motor systems. In the following,  the case of multi-motor systems in automotive applications is laid out by presenting the different vehicular systems comprising multiple motors.
  • 2.8K
  • 16 Aug 2022
Topic Review
“Singing” Multilayer Ceramic Capacitors and Mitigation Methods
Multilayer Ceramic Capacitors (MLCC) have a major role in modern electronic devices due to their small price and size, large range of capacitance, small ESL and ESR, and good frequency response. Unfortunately, the main dielectric material used for MLCCs, Barium Titanate, makes the capacitors vibrate due to the piezoelectric and electrostrictive effects. This vibration is transferred to the PCB, making it resonate in the audible range of 20 Hz–20 kHz, and in this way the singing capacitors phenomenon occurs. This phenomenon is usually measured with a microphone, to measure the sound pressure level, or with a Laser Doppler Vibrometer (LDV), to measure the vibration. Besides this, other methods are mentioned in the literature, for example, the optical fiber and the active excitation method. There are several solutions to attenuate or even eliminate the acoustic noise caused by MLCC. Specially designed capacitors for low acoustic levels and different layout geometries are only two options found in the literature. To prevent the singing capacitor phenomenon, different simulations can be performed, the harmonic analysis being the most popular technique. 
  • 2.8K
  • 06 Jun 2022
Topic Review
Guided Wave Ultrasonic Testing
Guided wave ultrasonic testing (GWUT) method is an effective method for long-distance inspection of inaccessible and coated structures from a single point of testing. It propagates inspection wave all through the structure without point-to-point scanning, hence, minimizes inspection drudgery and enhances work throughput per day.
  • 2.8K
  • 25 Feb 2021
Topic Review
Photovoltaic Solar Cells
A photovoltaic (PV) cell is the essential unit of a solar energy generation system in which sunlight is promptly converted to electrical energy. The solar cell is a p-n junction device. n-type refers to the negatively charged electrons donated by donor impurity atoms and p-type refers to the positively charged holes created by acceptor impurity atoms
  • 2.8K
  • 15 Jul 2022
Topic Review
Heterogeneous Networks
Communication technologies have drastically increased the number of wireless networks. Heterogeneous networks have now become an indispensable fact while designing the new networks and the way the data packet moves from device to device opens new challenges for transmitting the packet speedily, with maximum throughput and by consuming only confined energy. 
  • 2.8K
  • 23 Sep 2022
Topic Review
Substrate Integrated Waveguide
A Substrate integrated waveguide (SIW) (also known as post-wall waveguide or laminated waveguide) is a synthetic rectangular electromagnetic waveguide formed in a dielectric substrate by densely arraying metallized posts or via-holes which connect the upper and lower metal plates of the substrate. The waveguide can be easily fabricated with low-cost mass-production using through-hole techniques where the post walls consists of via fences. SIW is known to have similar guided wave and mode characteristics to conventional rectangular waveguide with equivalent guide wavelength. Since the emergence of new communication technologies in the 1990s, there has been an increasing need for high-performance millimeter-wave systems. These need to be reliable, low-cost, compact, and compatible with high-frequencies. Unfortunately, above 10 GHz, the well known microstrip and coplanar lines technologies cannot be used because they have high insertion and radiation losses at these frequencies. The rectangular waveguide topology can overcome these issues as it offers an excellent immunity against radiation losses and presents low insertion losses. But in their classical form, rectangular waveguide is not compatible with the miniaturization required by modern applications. The concept of SIW was developed in the early 2000s by Ke Wu to reconcile those requirements. The authors presented a platform for integrating all the components of a microwave circuit inside a single substrate, with a rectangular cross-section. Using a single substrate guarantees a limited volume and a simplicity of manufacture, while the rectangular cross-section of the line provides the advantages of the waveguide topology in terms of losses.
  • 2.8K
  • 27 Sep 2022
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