Main Power Research Articles

Nanoplastics causes heart aging/myocardial cell senescence through the Ca2+/mtDNA/cGAS-STING signaling cascade

BackgroundNanoplastics (NPs) are now a new class of pollutants widely present in the soil, atmosphere, freshwater and marine environments. Nanoplastics can rapidly penetrate cell membranes and accumulate in human tissues and organs, thus posing a potential threat to human health. The heart is the main power source of the body. But up to now, the toxicological effects of long-term exposure to nanoplastics on the heart has not been revealed yet.ResultsWe evaluated the effects of long term exposure of nanoplastics on cardiac cell/tissue in vitro and in vivo model. Furthermore, we explored the molecular mechanism by which nanoplastics exposure causes myocardial cell senescence. Immunohistochemistry, indirect immunofluorescence and ELISA were performed to detect the effects of nanoplastics on heart aging. We found that nanoplastics were able to induce significant cardiac aging through a series of biochemical assays in vivo. In vitro, the effects of nanoplastics on cardiac cell were investigated, and found that nanoplastics were able to internalize into cardiomyocytes in time and dose-dependant manner. Further biochemical analysis showed that nanoplastics induces cardiomyocytes senescence by detecting a series of senescence marker molecules. Molecular mechanism research shows that nanoplastics may cause mitochondrial destabilization by inducing oxidative stress, which leads to the leakage of mtDNA from mitochondria into the cytoplasm, and then cytoplasm-localized mt-DNA activates the cGAS-STING signaling pathway and promotes inflammation response, ultimately inducing cardiomyocytes senescence.ConclusionsIn this work, we found that nanoplastics exposure induces premature aging of heart. Current research also reveals the molecular mechanism by which nanoplastics induces cardiomyocyte senescence. This study laid the foundation for further studying the potential harm of nanoplastics exposure on heart.Graphical abstract

Monitoring Energy and Power Quality of the Loads in a Microgrid Laboratory Using Smart Meters

Microgrids are local energy production and distribution networks that can operate independently when disconnected from the main power grid thanks to the integration of power generation systems, energy storage units and intelligent control systems. However, despite their advantages, the optimal energy management of real microgrids remains a subject that requires further investigation. Specifically, an effective management of microgrids requires managing a large number of electrical variables related to the power generated by the microgrid’s power supplies, the power consumed by the loads and the aspects of power quality. This study analyzes how we can monitor different variables, such as the active power, reactive power, power factor, total harmonic distortion and frequency in the loads of a microgrid, using high-precision power meters. Our empirical study, conducted using a functional microgrid comprising a hybrid wind–solar power system and several household appliances, demonstrates the feasibility of using low-cost and high-performance power meters with IoT functionality to collect valuable power quality and energy consumption data that can be used to control the microgrid operation.

Direct deposition of air pollutants in the wake of container vessels: The missing term in the environmental impact of shipping

Understanding the deposition of pollutants produced by the operation of vessels is necessary to quantify air-water pollution interactions. This work develops and presents a novel model for calculating the amount of pollutants deposited on the sea water at the wake of vessels. Deposition depends on meteorological conditions, and vessel operation and design. The work was repeated for several subcategories of vessels included within the broader category of container ships and considered the impact of scrubber operation if such a system were installed on the vessel. Computational fluid dynamics (CFD) modelling was utilized, employing the open-source code OpenFOAM, to calculate the concentration of pollutants in the wake of the vessel. The sensitivity of deposition to different parameters was studied. The key parameters, including the wind relative speed and angle, the main engine power as a proxy for vehicle size, and the exhaust gas velocity, were combined to a single equation that can be used to predict deposition from sea-going container vessels. Direct deposition of pollutants (e.g., SO2) in the wake of vessels was found to be as much as 24 % of the total pollutant quantity produced, under favourable conditions. Direct deposition is so far neglected by air quality models that only report regional level deposition, starting from background ambient levels of pollution. This creates a bias to the predicted air and water pollution impacts. The use of the model proposed to whole vessel fleets, taking stock of the local weather conditions, will enable understanding the global impacts of direct deposition.

Enhanced proportional integral controller for DSTATCOM with particle swarm optimization algorithm in power system

Power system expansion planning is supported by using distributed generation (DG) instead of installing new main power system generators. The portability and autonomous operation of the DG make it capable of integrating into the distribution system. Power electronics devices for home loads, mainly electric vehicles, mobile phones, and laptops, introduce harmonics and related power quality issues to the distribution system. This load creates power quality issues like an increase in total harmonic distortion (THD) and a reduction in power factor. This paper uses the DG to supply important power electronics devices for the mitigation of power quality problems in distributed systems with non-linear loads, such as electric vehicles, called the “distributed static compensator (DSTATCOM)”. Wind and photovoltaic (PV) generators supply power to a common DC source. To improve power quality D-STATCOM powered by PV and wind energy systems at the DC link is incorporated. The direct axis/quadrature axis method (DQ method) controls the real and reactive components of the power. Proportional integral (PI) and particle swarm optimization (PSO) based PI controller parameter estimation are developed, and results are compared for power quality performance. In terms of improving power quality, the PSO-based parameter estimate of the PI controller performs better than the traditional PI controller.<br /><div class="extension_reset_css AnnotateNet_widget AnnotateReviewNotesButton" style="display: none; z-index: 2147483644;" data-id="ExtensionWidget"><div class="extension_reset_css AnnotateNet_widget annotateclickable" style="z-index: 8; display: none;" title="Resize" data-id="Widget"> </div></div>

Role of individual component failure in the performance of a 1-out-of-3 cold standby system: A Markov model approach

Abstract The current work assesses the availability and reliability of repairable 1-out-of-3 cold standby systems, undergoing switching failure, by the Markov models, where a finite set of differential equations govern the repairable system. A numerical approach based on KAOS programming in MATLAB is employed to solve the differential equations. Thus, numerical solutions for the time-dependent availability can then be obtained. The Laplace transform method is used for the reliability model to find the explicit form of the reliability function and the mean time to failure (MTTF) of the system. An availability estimation model for a 1-out-of-3 cold standby system is developed and the main electrical power network, local electricity generator, and domestic electricity generator are studied. Finally, the model is analyzed to illustrate the effect of both failures and repair rates as well as component capacity partitioning on system availability and MTTF.

A Study on Consumer’s Perception on Green Home Appliances

A household is the building block of the society and home appliances are the main power consumers in a household. Hence, they are the best means to save energy at a household level and achieve a reduction in per capita power consumption. If the household units save energy, the nation saves the energy and thereby the ideal place to initiate the green change at the consumer level is through the home appliances sector. Appliances more than 10 years old are clunkers as they use up most of the energy. If consumers replace them with energy efficient appliances, it will not only save billions of kilowatts of energy annually but also billions of tonnes of carbon emissions globally. Most of the home appliances have a longer life. Hence its medium to long term benefits should be weighed while making a purchase decision. “Despite various green initiatives and a vibrant consumer electronics market, consumer adoption of green home appliances is still lagging behind contributing to the high-power consumption and monetary loss to the individual and the country. The study made an attempt to understand consumer understanding, perceptions and acceptance of Green Home Appliances.

Kinematics and Trajectory Planning of 3-PSS/7R Spatial Hybrid Re-dundantly Driven Mechanism

A novel 3-PSS/7R spatial hybrid redundantly driven mechanism (HRDM) is proposed. The mechanism is driven by constant velocity (CV) motor and servo motor at the same time. The CV motor provides the main power for the system, and the servo motor plays the role of motion regulation. This system not only has the advantages of the traditional mechanical system, such as stable operation, large bearing capacity, but also can output controllable and adjustable flexible trajectory. The degrees of freedom of the mechanism are determined by the middle limb, which is called hybrid redundantly driven limb, which is driven by both CV motor and servo motor. Based on closed vector method, the position equation of the mechanism is established, and the velocity mapping matrix and acceleration change law of the mechanism are obtained. Further, the necessary and sufficient conditions for the mechanism to realize continuous trajectory and the relationship of rod constraints are obtained. The correctness of the kinematics equation and the smooth and controllable operation of the mechanism are verified by examples. The research results of this paper lay a foundation for the in-depth research and application expansion of spatial hybrid redundantly driven mechanism.

Resonant Gate Drive Circuit with Active Clamping to Increase Efficiency and Reliability

In power converters with high switching frequency, drive losses constitute a significant portion of the overall power losses. Resonant gate drivers can reduce drive losses, thereby enhancing the efficiency. However, resonant drivers suffer certain challenges: parameter drifts lead to the mismatch between the resonant frequency and the control frequency, and this mismatch can cause gate-to-source voltage overshoot. Moreover, the resonant driver is susceptible to external interference. This paper proposes a resonant circuit structure and control timing scheme aimed at overcoming these limitations. By incorporating a half-bridge clamp circuit, the proposed design achieves voltage clamping, thereby insulating the system from disturbances caused by mains power fluctuations. When there is a mismatch in resonant frequencies, the strategy employs a combination of hardware circuit diodes and control system timing to prevent overvoltage issues. Additionally, the utilization of MOSFETs minimizes the loss caused by prolonged current flow through body diodes, further reducing the resonant driving losses. Simulations have demonstrated the system’s stability under varying resonant parameters and its effective anti-interference capabilities in voltage clamping. Experiments achieved a power saving of 83.3% at a 1 MHz operating frequency. Both simulations and experimental validations confirm the feasibility of the proposed solution, its effectiveness in interference suppression, handling of resonant mismatches, and its role in further augmenting power conservation.

Evaluasi Sistem Proteksi Penangkal Petir pada Bangunan Power House Bandara Sams Sepinggan

The aim of this research is to solve the lightning protection system (which has been installed and to determine the effectiveness of the lightning protection system. In this research the evaluation method is carried out using data collection and data analysis methods. Data collection methods consist of, observation, measurement, literature study, and Interview. Data analysis consists of, Building needs for lightning protection, Determining protection, Distribution conductors, and Grounding. The evaluation results show that, based on the index stated in the standard (SNI 037014.1-2004) the Main Power House building really needs a lightning protection system. Based on the estimated danger of lightning strikes with a risk level of R=14 (highly recommended), the use of conventional lightning rods with the protection angle method still requires increased protection in the form of the addition of 5 air terminations (splitzers) on the right, left, front, side and back. and the distribution conductor and earth termination (grounding) for both lightning rods as a whole meet the standards.

Emergency power supply enabling solar PV integration with battery storage and wireless interface

ABSTRACT This paper presents a detailed investigation of an emergency power supply that enables solar photovoltaic (PV) power integration with a battery energy storage system (BESS) and a wireless interface. Through the utilisation of solar PV-based generation and BESS with wireless/contactless power transmission, the proposed method offers an easy-to-setup and flexible alternative solution for the emergency power supply (EPS) for household appliances and wireless electric vehicle (EV) charging for all weather conditions. During bad weather conditions, the battery acts as the main power supply and can be charged from the solar PV panel and during rainy days, it can be charged from the grid by the proposed wireless interface for emergency use. The proposed system is analysed by mathematical modelling, focusing on the interface of the solar PV, BESS, and load, with inductive power transfer (IPT) as a wireless power transfer (WPT) method. The simulation and a scaled-down experimental prototype are built to demonstrate that the proposed system enables wireless power transfer with PV and BESS, and easy installation can be achieved by just placing the primary charging coil of the proposed power supply close to the wireless charging pad that is available in the existing system for e.g. EV charging. The results show that the load voltage is kept constant at 48 V against the varying input characteristic of the solar panel which is the solar irradiance ranging from 20% to 100% and output characteristics of the load of the proposed integrated system with variation of 20–50%, respectively. Moreover, the wireless power transfer efficiency across the inductive coils is maintained at about 97% under these variations.

Constant Power Load Stabilization With Fast Transient Boundary Control for DAB-Converters-Based Electric Drive Systems

Due to the negative incremental impedance of constant power loads (CPLs), many undesirable issues such as the oscillations or even possible collapse of the main dc bus voltage may occur, which may significantly degrade the system stability of Electrical Vehicles (EVs). This paper presents a natural-switching-surface (NSS) fast-transient-boundary-control (FTBC) based stabilization solution for EVs with dual-active-bridge (DAB) converters as the main power interface. Based on the mathematical models of multiple natural switching surfaces (NSS) and characteristics of CPL, the proposed FTBC control can achieve stable operation of DAB converters feeding CPLs and fast dynamic response irrespective operating stages such as the startup, sudden voltage and power reference changing conditions. Compared with other strategies such as load shedding, the proposed FTBC has no additional requirements for hardware, which is cost-effective. The analytical derivation of the proposed algorithm under the CPL condition is presented together with simulation and experimental evaluations, which validate that the proposed FTBC is capable of achieving 2 times faster start-up process and at least 33% dynamic response improvement compared with proportional integrator (PI) closed-loop control while eliminating the dc-bias current and guaranteeing the CPL stability by regulating the dynamic trajectories of DAB converters in the geometric domain.

Numerical implications of including drifts in SOLPS-ITER simulations of EAST

The inclusion of drifts in plasma edge codes like SOLPS-ITER is required to match simulation data with experimental profiles. However, this remains numerically challenging. In this paper, the effect of some numerical factors on the final plasma solution is investigated. This study is performed on three EAST simulations in the upper single null configuration: an attached purely deuterium case, an attached case with limited Ne-seeding, and a detached Ne-seeded case. The effects of the anomalous conductivity and anomalous thermo-electric coefficient on the plasma potential are investigated. Next, the effect of the employed grids is shown. In order to investigate these effects, accurate drift simulations are needed. Therefore, the employed time step and numerical parameters are discussed for the three studied simulations. For all presented simulations, it is verified that the restriction of the grid to the first flux surface tangent to the main chamber wall is sufficient within the context of non-extended simulations. This means that the main power dissipation takes place inside the simulated domain, and only a small fraction of the power is leaving the B2.5 grid through the grid boundary closest to the first wall. Finally, the effect of drifts on the asymmetry between the inner and outer target for EAST simulations is demonstrated.

Design and control of LSTM-ANN controllers for an efficient energy management system in a smart grid based on hybrid renewable energy sources

Many isolated locations, including hilly areas, remote sites, and military camps, lack feasible access to the main power grid. In these conditions, locally established Microgrids can provide the necessary power supply. However, to meet the demands of these isolated areas, numerous individual Microgrids are required. Although some of these Microgrids might be integratable, geographical constraints may preclude full integration. Under these circumstances, the establishment of a smart grid—integrating multiple Microgrids with a battery management system—can potentially solve many power supply issues. A smart grid control system paired with a centralized battery management system is proposed in this paper. The system considers the use of multiple renewable energy sources at various locations for stable and reliable power generation. The proposed method incorporates a long short-term memory (LSTM)-based artificial neural network (ANN) to ensure a stable, high-quality power supply at different load buses. Additionally, this work introduces an artificial intelligence-based operating system designed to maintain energy management under various conditions. To enhance voltage quality, a 7-level aligned multilevel inverter is incorporated into the system. As compared with PI and Fuzzy controllers, the proposed method with LSTM-ANN controller is improved the power quality under sudden changes in the system which are also presented in results, Voltage variation of PI, Fuzzy, and LSTM-ANN is 370V,180V,and 70V . The effectiveness of the proposed energy management system (EMS) is verified by using a hardware-in the-loop approach with OPAL-RT modules, yielding realistic results.

A ZVS Branch-Sharing Partial Power Converter With Bipolar Voltage Regulation Capability

The isolated input-parallel-output-series (IPOS) partial power converter (PPC), which is composed of a dc transformer (DCX) cell and a voltage regulation (VR) cell, is regarded as a promising solution for dc distribution power systems for only a partial power is delivered by the VR cell under different voltage conditions. In this paper, a branch-sharing IPOS-PPC with bipolar voltage regulation capability is proposed, which is composed of two cells: 1) A half-bridge LLC resonant cell works at fixed switching frequency as a DCX with desired performance to realize isolation and main power conversion. 2) An auxiliary full-bridge/push-pull (FB/PP) cell is applied to realize the bipolar voltage regulation and the rest partial power conversion. Two cells share the lagging-leg of FB/PP cell to guarantee zero voltage switching (ZVS) in the whole load range from zero to full load. Compared with the traditional unipolar voltage regulation VR cell, the FB/PP cell can not only reduce the power processed by itself within the same voltage regulation range, but also reduce the component count and achieve a compact structure. Finally, a 180-300 V/ 48 V/ 1 kW experimental prototype is built to verify the feasibility and advantages of the proposed converter.

Design considerations of series type hybrid circuit breaker (S‐HCB)

AbstractThe series‐type direct current (DC) hybrid circuit breaker (S‐HCB) concept was previously reported to offer better performance than solid‐state circuit breakers (SSCB) and hybrid circuit breakers (HCB). S‐HCB offers low conduction power loss like an HCB and ‐scale interruption time, which is even faster than an SSCB. It uses a pulse transformer to isolate the lower‐voltage high‐inductance power electronic circuit from the high‐voltage, low‐inductance main power loop. This paper provides analysis of the impact of the S‐HCB circuit components on the overall system performance and a scalable S‐HCB design guide for different DC system voltage and current ratings. In addition, system energy flow analysis is performed in the time domain to provide an understanding of how energy is delivered, dissipated, and released throughout the entire fault interruption process. The S‐HCB prototype was experimentally tested at 3 kV/30 A and 6 kV/150A with the results showing the interruption of the low fault current of 30 A and the high fault current of 150 A within 8 and maintaining the fault current at a near zero value for 300 to enable an arcless opening of a series mechanical switch. The key design challenges of S‐HCB at high voltage and high current ratings were discussed and possible solutions to mitigate those challenges were introduced.

Effect of ice class to vessel fuel consumption based on real-life MRV data

Ice classed ships have specially designed, reinforced hulls and large engines, which may influence open-water fuel efficiency. Ice classification typically requires minimum engine power limit, possibly leading to an over-sized engine for open water operation. Most of the existing studies of energy efficiency of ice classed ships assume that these vessels consume more fuel also in open water conditions than conventional ships. In this work we analysed the EU Monitoring, Reporting and Verification database to understand the differences of main engine size, light ship mass, payload capacity and real-life reported and verified annual mean fuel consumption between ice classed ships and those without ice class using statistical methods. Ice classed ships were found to have on average 11% more hull mass, 13% more main engine power and 13% less deadweight capacity than ships without ice class, but some vessel types had inversed results. Also, ice class does not predict increased fuel consumption for all vessel types. In addition, according to the Automatic Identification System data, about 47% of vessels with reported ice class did not sail in ice covered areas during 2018–2022. These findings should open the discussion for more precise relief mechanisms of emission trading systems granted for ice classed vessels.

Analysis of the Influence of Fabrication Errors on the Far-Field Performance of Si and Si3N4 Antennas

Antennas are important components in optical phased arrays. However, their far-field performance deteriorates when random phase noise is introduced because of fabricating errors. For the first time, we use a finite-difference time-domain solution to quantitatively analyze the far-field characteristics of Si and Si3N4 antennas considering process errors. Under rough surface conditions based on a fishbone structure, we find that the quality of the main lobe of the Si antenna deteriorates badly, with −0.87 dB and −0.51 dB decreases in the sidelobe level and 5.78% and 3.74% deteriorations in the main peak power in the φ (phase-controlled) and θ (wavelength-controlled) directions, respectively. However, the Si3N4 antenna is only slightly impacted, with mere 0.39% and 0.71% deteriorations in the main peak power in the φ and θ directions, respectively, which is statistically about 1/15 of the Si antenna in the φ direction and 1/5 in the θ direction. The decreases in the sidelobe level are also slight, at about −0.08 dB and −0.01 dB, respectively. Furthermore, the advantages of the Si3N4 antenna become more remarkable with the introduction of random errors into the waveguide width and thickness. This work is of great significance for the design and optimization of OPA chips.

On-Grid Solar Traction System

World Railways is making significant progress in introducing high-speed trains to fulfil the increasing demands of the traveling public. Massive energy is needed for electric railroads. Many railroads operate their specialized power plants. An energy-storage grid-tied photovoltaic solar plant has been proposed as a strategy to boost the capacity of the rail network grid connection and enable the railway to become self-sufficient. To use the ballast-less rails as energy transporters, The current plan calls for installing solar panels along an HS train network. Ballast-free tracks require very little upkeep, and the space between them provides plenty of surface area for the installation of PV module arrays to harvest solar energy. This generated energy will feed into the main power line by using the concept of an on-grid solar system this energy is not more in numbers to drive the entire traction system, but it helps a lot. From this project we have developed hybrid parallel power sharing for the railway network, under this project the current will be shared in the main power line by matching the grid frequency and voltages. The primary power is solar when it can generate enough electricity. Still, in an abnormal condition, like in the absence of sunlight, the main power continuously feeds electricity without disturbing the traction system.

Coordinated management of electricity storages and distributed generation plant with predictive controllers in a power supply system with reduced electricity quality

THE PURPOSE. A study of the influence of coordinated control of electricity storage devices and distributed generation installations on the operating modes of a network cluster, which is an electrical distribution network connected to the AC railway power supply system through a direct current insert (DCI).METHODS. The studies were carried out using a simulation model implemented in the MATLAB system.RESULTS. The following disturbing influences were considered: turning off the main power supply of the network cluster from the DCI side for 0.5 seconds; three-phase short circuit with a duration of 0.5 s at the end of a 6 kV cable line with a length of two kilometers. The simulation results showed the effectiveness of coordinated control of electricity storage devices and a turbogenerator with self-adjusting predictive controllers. On this basis, the values of overshoot of the rotor speed are reduced and the transient process time is reduced for all parameters in various modes. For example, the transient time for the generator rotor speed in the mode of connecting an additional load is reduced by three times, and for voltage - by two times.CONCLUSION. Based on computer modeling, it is shown that coordinated control of electricity storage devices and a turbogenerator with predictive regulators reduces the amount of rotor speed overshoot to almost zero and reduces the transient process time by almost 90%. It is advisable to conduct further research on the application of the method of coordinated control of active elements used in the power supply system to regulate the mode parameters.

Personal safety monitoring system of electric power construction site based on AIoT Technology

For the purpose of real-time monitoring the hazard information on the electric power construction site, a personal safety monitoring system based on Artificial intelligence internet of things (AIoT) technology is designed. After the system sensing layer collects the gas information of the construction site through the gas sensor, limit current oxygen sensor and DS1820B temperature sensor, the edge computing device of the edge layer directly stores its calculation in the database of the platform layer through the data gateway. The Artificial Intelligence (AI) analysis module of this layer invokes the monitoring data of the power construction site of the database, and uses the personal safety identification method of the power construction site based on artificial intelligence technology, to complete the abnormal identification of monitoring data and realize personal safety monitoring. In addition, the system is also equipped with a power-fail detection module, which can collect the working voltage through the voltage transformer and compare it with the mains power standard to judge whether there is a power-fail risk, so as to prevent the problem of threatening personal safety due to the power-fail of the energized equipment. After testing, the system can monitor the operation status of the construction site in real time to protect personal safety.