Design Of Electrical Power System Research Articles

Negative Medium-Voltage Direct Current Discharges in Air under Simulated Sub-Atmospheric Pressures for All-Electric Aircraft

The increase in the global temperature due to greenhouse gas emissions is a major concern to the world. To achieve the goal of zero emissions by 2050 in the USA the practical realization of all-electric vehicles, particularly all-electric aircraft (AEA), is important. For the design of electrical power systems (EPSs) in all-electric aircraft, a bipolar medium-voltage direct current (MVDC) system of ±5 kV is being investigated. However, several challenges manifest when using such voltages in a low-pressure environment. One of the main challenges is the partial discharge (PD) behavior of the insulation. It is important to study the PD behavior of the insulation by simulating the aviation environment in the lab. This work aimed to study the partial discharge behavior of air under a negative DC voltage in a needle-to-plane electrode geometry by simulating the aviation pressures in the lab. The partial discharge inception voltage (PDIV) and the breakdown voltage (BDV) show an obvious pressure-dependent variation. Regression analysis was performed to better understand the relationship between the PDIV and pressures. Plots were drawn for the average discharge current at each voltage step until breakdown. This paper’s findings can provide valuable insight into the design of EPS for an AEA. To the best of our knowledge, such a study has not been carried out to date.

Power Systems and Power Electronics using the DEMATEL Method

Energy and research on energy systems places a focus on all facets of electrical energy, as well as innovation in energy production and delivery, alternative resources, and efficient devices. Systems and equipment for converting, providing, and utilising energy as a kind of electricity are the subject of research initiatives. Power electronics are now a more integral part of power systems, enhancing quality and efficiency and fostering the gradual materialization of intelligent, efficient energy. Many different types of power electronics exist in power systems. The architectural study of changing electrical transformed from one medium to another is known as power electronics. Fields such as electronics reprocess or recover more than 80percent of the entire of the electricity produced at a world average rate of 3.4 billion kilowatts per hour each year. Power electronics converters, sometimes referred to as power converters or switching converters, are used to process or convert electrical energy. Electricity comes in two flavours: AC power and DC power. The distribution system is divided into AC distribution systems and DC distribution systems based on the type of power it uses. Power system analysis is an essential part of electrical power system design. Calculations and simulations are performed to verify that the electrical system, including the system components, is properly specified to perform as planned, withstand the expected stress, and be protected from failures. Advantages of Power Electronics: High power density electricity. Improved efficiency up to 99% in energy conversion. Because to its efficiency and dependability, switching power supply are also being used in medical devices with acoustically sensitive applications. Power system reliability, in general, relates to problems like service interruption and power outages. This is frequently described as a goal to try relying on codes specifically relevant to the consumer. SAIFI, SAIDI, and CAIDI are common dependability index values for US applications. DEMATEL (Decision Making Trial and Evaluation Laboratory) They are divided into analysis using the Nonmetal mineral product industry, General equipment manufacturing, Mining and washing of coal, Textile industry, Food manufacturing industry It is the interaction between the factors Visualized and assesses dependent relationships Through the structural model Also deals with identifying important. Power Electronics in Power Systems, Power Electronics in Transportation Systems, Energy Conservation, Heating & Lighting Control and Renewable Energy Integration Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank. Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank.

Synergies and Trade-Offs in Hybrid Propulsion Systems Through Physics-Based Electrical Component Modeling

Abstract Hybrid-electric propulsion is recognized as an enabling technology for reducing aviation's environmental impact. In this work, a serial/parallel hybrid configuration of a 19-passenger commuter aircraft is investigated. Two underwing-mounted turboprop engines are connected to electrical branches via generators. One rear fuselage-mounted electrically driven ducted fan is coupled with an electric motor and respective electrical branch. A battery system completes the selected architecture. Consistency in modeling accuracy of propulsion systems is aimed for by development of an integrated framework. A multipoint synthesis scheme for the gas turbine and electric fan is combined with physics-based analytical modeling for electrical components. Influence of turbomachinery and electrical power system design points on the integrated power system is examined. An opposing trend between electrical and conventional powertrain mass is driven by electric fan design power. Power system efficiency improvements in the order of 2% favor high-power electric fan designs. A trade-off in electrical power system mass and performance arises from oversizing of electrical components for load manipulation. Branch efficiency improvements of up to 3% imply potential to achieve battery mass reduction due to fewer transmission losses. A threshold system voltage of 1 kV, yielding 32% mass reduction of electrical branches and performance improvements of 1–2%, is identified. This work sets the foundation for interpreting mission-level electrification outcomes that are driven by interactions on the integrated power system. Areas of conflicting interests and synergistic opportunities are highlighted for optimal conceptual design of hybrid powertrains.

TFODn‐FOPI multi‐stage controller design to maintain an islanded microgrid load‐frequency balance considering responsive loads support

AbstractModern electrical power system design will increase renewable energy sources (RES) dominance. Rotating masses, the main source of inertia in power systems, have been greatly decreased in renewable energy producing systems. Thus, load–frequency equilibrium is an important indicator of these systems' performance and safety. This work introduces a fractional‐order (FO) operator‐based cascade control structure for islanded microgrid (μG) load‐frequency control (LFC). The structure utilizes a tilt–FO derivative with filter (TFODn) in the first level to reduce noise. The second level implements the proportional integral (PI) controller's FO form (FOPI), making it a tilt–FO derivative with a filter cascaded to the FOPI controller (TOFDn‐FOPI). The optimal controller parameters for quick dynamic responses with low frequency fluctuation are determined using a unique cost function and prairie dog optimization (PDO) algorithm. The LFC control loops have frequency deviation‐based responsive loads (RL). Control signal delays, RES output changes, parameter uncertainties, and cyber vandalism are examined. Laboratory‐scale tests also assessed the controller's practicality. The proposed controller outperforms standard and FO type proportional integral derivative (PID) and PD‐PI controllers. The TFODn‐FOPI controller is suitable for complicated closed‐loop systems like islanded μGs due to its faster error clearing, reduced RL capacity, and superior time and frequency domain indicators.

Progressive failure and seismic fragility analysis for transmission towers considering buckling effect

Transmission towers are essential components supporting the operation of the power grid. Accurately predicting their ultimate bearing capacity and progressive failure improve the performance design of electrical power systems. This paper proposes a progressive failure method for transmission towers considering the buckling and post-buckling behaviors of steel angles. To simulate the nonlinear hysteretic behaviors of steel angles, a phenomenological hysteretic model (PHM) is introduced and embed into the ABAQUS software by calling a user-defined subroutine VUMAT. The accuracy and reliability of the PHM are verified through a full-scale test of a transmission tower. The comparison results demonstrate that the PHM can accurately reproduce the displacement and strain responses of the transmission tower and the ultimate bearing capacity, with a maximum error of <15%. The buckling failure of leg members is the main factor for the collapse of the transmission tower. The study also investigates the progressive failure process of the transmission tower under strong earthquakes and estimates the collapse fragility and seismic losses. The results reveal that early failures of steel angles may alter the local force transmission path of the tower and eventually lead to its collapse. This research provides suggestions for the structural optimization and design decision-making of transmission towers.

On‐board energy scheduling optimization algorithm for nanosatellites

SummaryThis work proposes a real‐time and online energy scheduling optimization algorithm for nanosatellites operating with a direct energy transfer (DET) architecture. The goal of the algorithm is to optimize energy utilization by maximizing energy harvesting, meeting task deadlines and priorities, and ensuring a minimum quality of service (QoS) for the system. The algorithm is composed of a modified perturb and observe algorithm to reach the best energy efficiency point of the solar panels, a task prioritization algorithm to guarantee their times and minimum QoS, and a backpack optimization problem to maximize the energy efficiency of the satellite. To demonstrate the effectiveness of the proposed algorithm, simulations of a nanosatellite operating in a given orbit, attitude, and thermal parameters were conducted and compared to other task scheduling strategies. The results showed that the proposed energy scheduling algorithm had the best performance in terms of energy balance and average power consumption, with an energy balance up to 16% higher compared to the other tested strategies. This demonstrates the ability of the proposed algorithm to optimize power consumption and energy utilization, as well as efficiently schedule tasks to maximize energy harvesting. The proposed energy scheduling optimization algorithm has the potential to be a useful tool for the design and optimization of future satellite missions and could potentially guide the design of electrical power systems for new CubeSat missions operating with a DET architecture. The algorithm's ability to optimize energy utilization and ensure a minimum QoS for the system could improve the overall efficiency and performance of the satellite.

Influence of busbar trunking system design on thermal performance operating with non-sinusoidal currents

The selection of busbar trunking systems is crucial for operational safety and reliability in electrical power systems. However, harmonic currents created by semiconductor-based converters reduce the current carrying capacity of busbar trunking systems, especially in electric vehicle charging stations, energy storage systems, microgrids, and data centers. In this case, busbar trunking systems with two neutrals or increased cross-section could be used for operating conditions with harmonic currents. Therefore, this study examines the thermal performance of the busbar trunking systems with different design parameters when loaded with harmonic currents. For this purpose, coupled electromagnetic field and thermal analyses were carried out using the finite element method. As expected, the results show that the maximum temperature in the temperature distributions increases significantly when busbar trunking systems are loaded with non-sinusoidal currents. Furthermore, the analysis studies determined the loading limits of busbar trunking systems within the thermal restriction when operating with non-sinusoidal currents. Accordingly, depending on the conductor’s phase sequences, the busbar trunking system model with one neutral conductor can be loaded with between 20% and 25%, two neutral conductors model can be loaded with between 22% and 39%, and the busbar trunking system model with 25% increased conductor cross-sections can be loaded with between 39% and 44% harmonic current. The results show that in the case of loading with non-sinusoidal currents, especially at a high portion of third harmonic components, choosing a busbar trunking system with a high cross-section area is advantageous compared to using two neutral conductors. This information is crucial to system reliability in electrical power system design. Therefore, it has become necessary to conduct these evaluations according to the equipment used while designing the electrical power system. • The proper selection of BTS is crucial for safety and reliability in power systems. • Magnetic and thermal analyses were carried out with the FEA for different BTS models. • Increasing the conductor cross-sectional area gives lower temperature rises. • These analyses are especially crucial for electric vehicle charging stations.

Development of control algorithms for magnetoelectric generator with axial magnetic flux and double stator based on mathematical modeling

The object of this research is electromechanical processes in a generator with an axial magnetic flux and a double stator and an additional non-contact excitation winding operating as part of autonomous electric power systems. The power of the additional excitation system is about 2 % of the generator power. The presence of an additional non-contact winding, which is powered by direct current, makes it possible to control the generator voltage by changing the excitation current. This resolves the task to stabilize the output voltage of the generator with permanent magnets when the load and shaft speed change. This paper reports the construction of a three-dimensional field axisymmetric mathematical model of the generator under study, which has made it possible to calculate and investigate its characteristics and parameters, in particular the magnitude of magnetic induction in all structural elements. The model built takes into account the influence of finite effects, magnetic scattering fields, and the radial-axial nature of the closure of the main magnetic flux and the magnetic flux of the additional excitation winding. The use of a structure with a double stator makes it possible to more efficiently utilize the usable volume of the generator and to increase its power. A mathematical model of the generator in the d-q coordinate system was built, which has made it possible to synthesize algorithms for controlling the automatic voltage stabilization system of the generator voltage under conditions of change in load and shaft speed. Control algorithms were developed on the basis of the concept of inverse dynamics problems in combination with minimizing local functionalities of instantaneous energy values, which ensures that the system is robust when changing generator parameters and that regulators are implemented in a simple way, due to the lack of differentiation operations. Based on the models built and algorithms developed, the quality of control of the generator's output voltage when the load and frequency of the generator change was investigated by modeling in the MATLAB/Simulink environment. When setting a jump in the rated load and changing the rotational speed within ±15 % of the rated value, the automatic stabilization system provides astatic voltage control at a given level of 48 V. The results can be practically used in the design of autonomous electric power systems with high energy conversion efficiency, in particular wind turbines and hydraulic units

Design of Electric Power System for Xinhangcheng Station on Intercity Railway Connecting Line

At present, the intercity railway station is getting bigger and bigger, represented by the Intercity Railway Xinhangcheng Station. Xinhangcheng Station of the Intercity Railway Link Line is a key station for the national railway underground passenger transport, the scale of the building is larger than that of ordinary subway stations, with a total of 6 floors, including communication, signal, information, escalator, screen door and other equipment. The layout and design of ventilation, water supply, and fire-fighting equipment are more complicated than subways. The station also includes areas related to station support and integrated development, therefore, new requirements are put forward for the design of the station power system. Therefore, it is very important to study a reasonable and feasible power design scheme. In this paper, to meet the needs of the intercity railway tie line underground station building, station supporting and integrated development of electricity consumption and electricity consumption independent of each other, a 10KV/0.4KV substation is set up on the ground floor and on the second floor of the station building to supply power to the station, a 10KV/0.4KV substation is set up on the east and west sides of the supporting area to supply power to the municipal supporting area, and integrated development of a 10KV/0.4KV substation is set up to supply power for integrated commercial development, meeting the needs of all parties.

Risk-based design of electric power systems for non-conventional nuclear facilities at shutdown modes

The work presents a methodology for assessing the safety of electrical system designs for non-conventional nuclear facilities in shutdown. The methodology adopts the core damage frequency as the main risk measure to assess the different architectures of power systems in a non-conventional nuclear facility. Among the reasons is the absence of a specific regulatory basis for this type of installation. The adoption of standards for nuclear power plants by non-conventional nuclear facilities does not take into account the functional and operational particularities of these installations, imposing criteria that are often overestimated, which can even lead to an increase in the financial risk for carrying out the projects. Safety probabilistic analyzes become essential tools for the facilities design and licensing. The modeling and quantification of systems failures in charge of ensuring the nuclear safety of non-conventional nuclear facilities are carried out in the CAFTA software environment. In these studies, the analysis of electrical system configurations and their influence on the overall risk of the installation stand out.

Modular Bidirectional Solid-State DC Circuit Breaker for Next-Generation Electric Aircrafts

The design of electric power systems (EPSs) for the aviation industry has become a major research area to reduce the global annual CO2 emission caused by the transportation sector. DC power distribution is envisaged to meet the high load demand of more-electric and all-electric aircraft power architectures. Nonetheless, the development of dc distribution is significantly impeded by the challenges associated with dc system protection. Aircraft EPS demands high speed and high current protection. Among various dc circuit breaker (DCCB) technologies, solid-state dc circuit breakers (SSCBs) operate at higher speeds. To make them withstand high current ratings, modular structured DCCBs with the highest power density, reliability, and bidirectional fault interruption capability are presented in this article. The existing DCCBs fail to comply with the design constraints such as faster response, high current breaking, and compact design. This article proposes a coupled inductor-based modular bidirectional SSCB that employs the magnetic coupling principle for counter-current commutation of thyristors. The proposed modular SSCB exhibits a fast fault interruption time of approximately 200 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{s}$ </tex-math></inline-formula> . The analysis, design, and experimental validation of the proposed SSCB are presented in detail. Each module in the prototype is designed for a system rating of 270 V/15 A. The performance of this SSCB for single- and two-module operations is experimentally verified for a 270-V/20-A dc system.

A Comprehensive Review on Small Satellite Microgrids

The small satellite (SmallSat) industry has recorded incredible growth recently. Within this class, among mini-, micro-, and nanosatellites, the cube satellite (CubeSat) is primed for an explosion of growth. These satellites are fascinating for remote sensing, Earth observation, and scientific applications. Remarkable attention from the space operators makes it valuable because of its low cost, cubic shape, less manufacturing time, lightweight, and modular structure. Among the various subsystems comprising the SmallSat, the electrical power system (EPS) is the most crucial one because unreliable power supply to the rest is most of the time detrimental to the mission. The EPS is formed by electrical sources, storage units, and loads, all interconnected via different power converters, the operation of which must be closely orchestrated to accomplish efficient use of photovoltaic power, optimal battery management, and resilient power delivery. At the same time, the EPS design must address a series of challenges such as size restrictions, high power density, and harsh space environments (e.g., atomic oxygen, radiation, and extreme temperatures), which significantly impact the EPS electrical and electronic equipment. In terms of power systems, a SmallSat EPS can be considered a space microgrid owing to coordination and control of distributed generation, storage, and loads in a small-scale electrical network. From this point of view, this article reviews and explores SmallSat microgrid's research developments, energy transfer and architectures, converter topologies, latest technologies, main challenges, and some potential solutions, which will enable building a more robust, resilient, and efficient EPS. The research gaps and future developments are underlined before this article is concluded.

Reliability Assessment Based on Optimal DGs Planning in the Distribution Systems

Due to increased load demands, distribution systems suffer from high power losses, low voltage levels, high current, and low reliability. To solve these problems, integrate distributed generator units (DG) into the distribution system. DG units are among the most popular methods of improving distribution system reliability, power losses, and bus voltage improvement through the placement and selection of distributed generator units in an optimal location and size. This work proposed Enhanced Particle Swarm Optimization (EPSO) technology to find the optimum location and size of DG units to reduce power losses, improve bus voltage level, and employed the Transient Electricity Analyzer (ETAP) to evaluate the reliability of the distribution system network. ETAP is a programming tool for modeling, analysis, design, optimization, operation, and control of electrical power systems. These findings may be useful in conducting reliability assessments and correctly utilizing dispersed generation sources for future power system growth by power utilities and power producer companies. The proposed method was employed on the Iraqi distribution system (AL-Abasia distribution network (F10 feeder)). After adding three DG units to the distribution system, theer adding three DG units to the distribution system, the obtained simulation results showed a significant reduction in power losses, voltage levels, and reliability enhancement.

Investigate the optimal power system by using hybrid optimization of multiple energy resources software

Increasing the effects of global pollution and the availability of renewable energy sources has push many countries to use reasonable energy sources such as wind and solar energy. This paper presents a case study of evaluating a hybrid renewable energy system by using a hybrid optimization of multiple energy resources (HOMER) software program based on the entered data available from the net for the considered location. The hybrid system consisting of a wind turbine, a photovoltaic system, a battery and a diesel generator. The simulation results are presented in a graphical curves n HOMER software. The obtained results indicate that by using the HOMER simulation program, the optimal design of the hybrid electrical power system for the considered location can be achieved which can help the designer to decide the types and number of the competent required for conducting the intending hybrid electrical power system which results in optimum output power in addition to reducing the overall operating costs.

Reliability Uncertainty Analysis Method for Aircraft Electrical Power System Design Based on Variance Decomposition

As a safety critical system, affected by cognitive uncertainty and flight environment variability, aircraft electrical power system proves highly uncertain in its failure occurrence and consequences. However, there are few studies on how to reduce the uncertainty in the system design stage, which is of great significance for shortening the development cycle and ensuring flight safety during the operation phrase. For this reason, based on the variance decomposition theory, this paper proposes an importance measure index of the influence of component failure rate uncertainty on the uncertainty of power supply reliability (system reliability). Furthermore, an algorithm to calculate the measure index is proposed by combining with the minimum path set and Monte Carlo simulation method. Finally, the proposed method is applied to a typical series-parallel system and an aircraft electrical power system, and a criteria named as “quantity and degree optimization criteria” is drawn from the case study. Results demonstrate that the proposed method indeed realizes the measurement of the contribution degree of component failure rate uncertainty to system reliability uncertainty, and combined with the criteria, proper solutions can be quickly determined to reduce system reliability uncertainty, which can be a theoretical guidance for aircraft electrical power system reliability design.

A Comprehensive Review on CubeSat Electrical Power System Architectures

CubeSats have been popular for space research due to lower cost, faster development, and easier deployment. The electrical power system (EPS) is one of the significant subsystems for the CubeSat since it handles power generation, energy storage, and power distribution to all other subsystems. Therefore, the design of EPS becomes crucial for successful CubeSat mission, wherein the first step is the selection of EPS architecture. The main objective of this article is to present an extensive review of all the conventional and emerging EPS architectures of CubeSats. A total of 17 categories of CubeSat EPS architectures have been identified, classified, and the operational aspects of these architectures are presented in addition to a qualitative comparison. This article is expected to provide a useful reference guide for all the researchers and developers working in the area of CubeSats EPS. Also, some of the potential research topics are provided to further exploration and innovation for the CubeSat EPS.

Wind Diesel Hybrid System with Pitch Angle Controller

A wind diesel hybrid system is an autonomous electricity generating system using wind turbines with diesel generators to obtain a maximum contribution by the intermittent wind resource to the total power produced, while providing continuous high quality electric power. The main goal is to control load frequency and reduce fuel consumption enabling reduced system operating costs and environmental impacts. Frequency control in a power system is done to maintain an adequate balance between the consumed and generated active powers, so that the frequency remains within acceptable limits around the nominal frequency. Load–frequency control (LFC) is of importance in electric power system design and operation. The objective of the LFC in an interconnected power system is to maintain the frequency of each area within limits and to keep tie-line power flows within some pre-specified tolerances by adjusting the MW outputs of the generators so as to accommodate fluctuating load demands.

Harmonics Mitigation of a Solar PV-Fuel Cell Based Microgrid System using a Shunt Active Power Filter

The increased penetration of distributed energy resources is inspiring the entire design of conventional electrical power systems. A Microgrid (MG) includes distributed generation, loads, energy storage, and a control system capable of operating in grid-connected mode and/or island mode. The power quality (PQ) issue is one of the main technical challenges in an MG power system. To improve PQ, it is necessary to analyze the harmonic distortion of the system. Moreover, harmonic distortion in MG networks has significantly reduced PQ, affecting the stability of the system. The shunt active power filter (SAPF) has been extensively used to diminish the current harmonics and verified as being the best solution. Hence, in this paper, the impact of PQ issues in an adopted standalone MG system (comprising solar and fuel cell based renewable energy sources) is investigated in the presence of SAPF. The SAPF is realized using a conventional synchronous reference frame (SRF) technique for current generation with a pulse-width modulation voltage source inverter technique to generate pulses for the inverter along with a PI controller to regulate the DC-link capacitor voltage. The proposed model is developed in MATLAB/SIMULINK and the results validate the superiority of the proposed technique over others in terms of harmonic elimination.

The Method of “Characteristic” Currents and Countercurrents for Short Circuits Diagnosis

Many software are available to analyze the design of electrical power systems. Therefore, it becomes relevant to know the rules of thumb to be able to diagnose in an elementary and intuitive way the computerized results. For the short-circuit analysis, in most practical cases, it is sufficient to adopt simplified and standard-based calculation methods. This article introduces the parameter of the countercurrents and illustrates the approach of the short-circuit models of power system components based on the “characteristic” currents method. This article, at first, presents a short overview of the IEC Std 60909, assumed as a reference for the proposed approach.

Comparison of Peak Power Tracking Based Electric Power System Architectures for CubeSats

CubeSats have been widely used for space research due to lower cost and faster development. The electric power system (EPS) is one of the key subsystems of CubeSat which powers all the other subsystems. One of the important steps in the EPS design is the selection of EPS architecture which should be done considering overall efficiency, battery size, reliability, and simplicity of control. In the literature, a general comparison between different architectures is performed without considering the mission parameters, power generation profile, and load profile based on the operational modes. Thus, the best possible EPS architecture may not be selected in the design phase. Therefore, the main objective of this article is to develop a systematic methodology to compare various peak power tracking EPS architectures of CubeSat in terms of orbital efficiency for all possible modes of operation, component count, reliability, and battery size to meet the required number of cycles of charge/discharge for the given mission duration. The proposed methodology has been demonstrated using the real data and scenarios of MYSAT-1, which is a 1U CubeSat developed and launched by Khalifa University. The results demonstrate that EPS architecture with series-connected maximum power tracking converters for solar panels and unregulated dc-bus has the highest efficiency for all operating modes, lower component count, higher reliability, and minimum battery capacity or longer lifetime for the same battery specifications.