A Wide-range Reconfigurable Deadtime and Delay Element for Optimal-Power Conversion

2021 ◽  
Author(s):  
Mousa Karimi ◽  
Mohamed Ali ◽  
Ahmad Hassan ◽  
Mohamad Sawan ◽  
Benoit Gosselin
Keyword(s):  
Power Conversion ◽  
Delay Element ◽  
Optimal Power ◽  
Wide Range

Designing the Electricity Market with Energy Storage Devices

2020 ◽  
Vol 12 (12) ◽  
pp. 31-43
Author(s):  
Tatiana A. VASKOVSKAYA ◽  
◽  
Boris A. KLUS ◽  
Keyword(s):  
Energy Storage ◽  
Electricity Market ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Storage Systems ◽  
Energy System ◽  
Energy Storage Systems ◽  
Storage Model ◽  
Optimal Power ◽  
Wide Range

The development of energy storage systems allows us to consider their usage for load profile leveling during operational planning on electricity markets. The paper proposes and analyses an application of an energy storage model to the electricity market in Russia with the focus on the day ahead market. We consider bidding, energy storage constraints for an optimal power flow problem, and locational marginal pricing. We show that the largest effect for the market and for the energy storage system would be gained by integration of the energy storage model into the market’s optimization models. The proposed theory has been tested on the optimal power flow model of the day ahead market in Russia of 10000-node Unified Energy System. It is shown that energy storage systems are in demand with a wide range of efficiencies and cycle costs.

Incident-angle-controlled semitransparent colored perovskite solar cells with improved efficiency exploiting a multilayer dielectric mirror

Nanoscale ◽  
2017 ◽  
Vol 9 (37) ◽  
pp. 13983-13989 ◽  
Author(s):  
Kyu-Tae Lee ◽  
Ji-Yun Jang ◽  
Sang Jin Park ◽  
Song Ah Ok ◽  
Hui Joon Park
Keyword(s):  
Solar Cells ◽  
Visible Light ◽  
Power Conversion Efficiency ◽  
Conversion Efficiency ◽  
Incident Angle ◽  
Power Conversion ◽  
Perovskite Solar Cells ◽  
Dielectric Mirror ◽  
Wide Range ◽  
Multilayer Dielectric

See-through colored perovskite solar cells that exploit a dielectric mirror are demonstrated. The dielectric mirror strongly reflects a wide range of visible light back to a photoactive layer for efficient light-harvesting, yielding 10.12% power conversion efficiency, with iridescent semitransparent colors.

Observer-Based Power Management for Multi-Source Electric Vehicles Using Optimized Splitting Ratios

2018 ◽  
Author(s):  
Ahmed M. Ali ◽  
Dirk Söffker
Keyword(s):  
Power Conversion Efficiency ◽  
Real Time ◽  
Power Management ◽  
Conversion Efficiency ◽  
Electric Vehicles ◽  
Control Method ◽  
Power Conversion ◽  
Observer Design ◽  
Power Handling ◽  
Optimal Power

Optimal power management in real-time is a core technology of hybrid electric vehicles (HEVs). The online application of optimized power split ratios based on driver demand is a promising approach allowing near optimal power handling decisions in real-time. However, the fulfillment of exact power delivery (driveability) is an open challenge of this approach due to interpolation of driver’s demand to the optimized discrete solutions. Finding balanced power management that handles unscheduled loads and sustains required power conversion efficiency may significantly improve the experimental application of this approach. This work proposes an observer-based control method integrated to the power management system that ensures better driveability with minimal effect on power handling optimality. Modeling of traction system for observer design is based on a simplified brushless DC motor model. Identification of system parameters is achieved by a newly introduced error minimization algorithm using NSGA-II to obtain the same dynamic response as the original system. Results analysis shows 7% reduction of power consumption and 98% improvement of driveability at minimal mitigation of power conversion efficiency.

Bipyridine type Co-complexes as hole-transporting material dopants in perovskite solar cells

RSC Advances ◽  
2016 ◽  
Vol 6 (21) ◽  
pp. 17354-17359 ◽  
Author(s):  
Jiajiu Ye ◽  
Li Zhou ◽  
Liangzheng Zhu ◽  
Xuhui Zhang ◽  
Zhipeng Shao ◽  
...  
Keyword(s):  
Solar Cells ◽  
Power Conversion Efficiency ◽  
Conversion Efficiency ◽  
Power Conversion ◽  
Perovskite Solar Cells ◽  
Cobalt Complexes ◽  
Optimal Power ◽  
Hole Transporting ◽  
Hole Transporting Material

This work focuses on preparing a series of substituted bipyridine cobalt complexes as HTM dopants using a co-solvent of dichloroethane and acetylacetone as the HTM solvent, achieving an optimal power conversion efficiency of 14.91%.

scholarly journals Influences of InGaP Conical Frustum Nanostructures on the Characteristics of GaAs Solar Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Nguyen Dinh Lam ◽  
Youngjo Kim ◽  
Kangho Kim ◽  
Jaejin Lee
Keyword(s):  
Refractive Index ◽  
Solar Cells ◽  
Power Conversion Efficiency ◽  
Power Conversion ◽  
Window Layer ◽  
Gradual Change ◽  
Single Junction ◽  
Wide Range ◽  
Photovoltaic Characteristics ◽  
Lithography Technique

Conical frustums with quasihexagonal nanostructures are fabricated on an InGaP window layer of single junction GaAs solar cells using a polystyrene nanosphere lithography technique followed by anisotropic etching processes. The optical and photovoltaic characteristics of the conical frustum nanostructured solar cells are investigated. Reflectance of the conical frustum nanostructured solar cells is significantly reduced in a wide range of wavelengths compared to that of the planar sample. The measured reflectance reduction is attributed to the gradual change in the refractive index of the InGaP conical frustum window layer. An increase of 15.2% in the power conversion efficiency has been achieved in the fabricated cell with an optimized conical frustum nanostructure compared to that of the planar cell.

scholarly journals Customized Sequential Quadratic Programming for Solving Large-Scale AC Optimal Power Flow

2021 ◽  
Author(s):  
Sayed Abdullah Sadat ◽  
mostafa Sahraei-Ardakani
Keyword(s):  
Quadratic Programming ◽  
Sequential Quadratic Programming ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Large Scale ◽  
Optimization Problems ◽  
Test Cases ◽  
Time Limits ◽  
Optimal Power ◽  
Wide Range

After decades of research, efficient computation of AC Optimal Power Flow (ACOPF) still remains a challenge. ACOPF is a nonlinear nonconvex problem, and operators would need to solve ACOPF for large networks in almost real-time. Sequential Quadratic Programming (SQP) is one of the powerful second-order methods for solving large-scale nonlinear optimization problems and is a suitable approach for solving ACOPF with large-scale real-world transmission networks. However, SQP, in its general form, is still unable to solve large-scale problems within industry time limits. This paper presents a customized Sequential Quadratic Programming (CSQP) algorithm, taking advantage of physical properties of the ACOPF problem and the choice of the best performing ACOPF formulation. The numerical experiments suggest that CSQP outperforms commercial and noncommercial nonlinear solvers and solves test cases within the industry time limits. A wide range of test cases, ranging from 500-bus systems to 30,000-bus systems, are used to verify the test results.

scholarly journals Customized Sequential Quadratic Programming for Solving Large-Scale AC Optimal Power Flow

2021 ◽  
Author(s):  
Sayed Abdullah Sadat ◽  
mostafa Sahraei-Ardakani
Keyword(s):  
Quadratic Programming ◽  
Sequential Quadratic Programming ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Large Scale ◽  
Optimization Problems ◽  
Test Cases ◽  
Time Limits ◽  
Optimal Power ◽  
Wide Range

After decades of research, efficient computation of AC Optimal Power Flow (ACOPF) still remains a challenge. ACOPF is a nonlinear nonconvex problem, and operators would need to solve ACOPF for large networks in almost real-time. Sequential Quadratic Programming (SQP) is one of the powerful second-order methods for solving large-scale nonlinear optimization problems and is a suitable approach for solving ACOPF with large-scale real-world transmission networks. However, SQP, in its general form, is still unable to solve large-scale problems within industry time limits. This paper presents a customized Sequential Quadratic Programming (CSQP) algorithm, taking advantage of physical properties of the ACOPF problem and the choice of the best performing ACOPF formulation. The numerical experiments suggest that CSQP outperforms commercial and noncommercial nonlinear solvers and solves test cases within the industry time limits. A wide range of test cases, ranging from 500-bus systems to 30,000-bus systems, are used to verify the test results.

scholarly journals Numerical Performance of Different Formulations for Alternating Current Optimal Power Flow

2021 ◽  
Author(s):  
Sayed Abdullah Sadat ◽  
Kibaek Kim
Keyword(s):  
Nonlinear Optimization ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Large Scale ◽  
Optimization Problems ◽  
Alternating Current ◽  
Box Constraints ◽  
Optimal Power ◽  
Wide Range ◽  
The Impact

<div>Alternating current optimal power flow (ACOPF) problems are nonconvex and nonlinear optimization problems. Utilities and independent service operators (ISO) require ACOPF to be solved in almost real time. Interior point methods (IPMs) are one of the powerful methods for solving large-scale nonlinear optimization problems and are a suitable approach for solving ACOPF with large-scale real-world transmission networks. Moreover, the choice of the formulation is as important as choosing the algorithm for solving an ACOPF problem. In this paper, different ACOPF formulations with various linear solvers and the impact of employing box constraints are evaluated for computational viability and best performance when using IPMs. Different optimization structures are used in these formulations to model the ACOPF problem representing a range of sparsity. The numerical experiments suggest that the least sparse ACOPF formulations with polar voltages yield the best computational results. Additionally, nodal injected models and current-based branch flow models are improved by enforcing box constraints. A wide range of test cases, ranging from 500-bus systems to 9591-bus systems, are used to verify the test results.</div>

scholarly journals Integrative analysis of relative abundance data and presence-absence data of the microbiome using the LDM

2022 ◽  
Author(s):  
Zhengyi Zhu ◽  
Glen A Satten ◽  
Yi-Juan Hu
Keyword(s):  
Relative Abundance ◽  
R Package ◽  
Data Types ◽  
Omnibus Test ◽  
Testing Hypotheses ◽  
Abundance Data ◽  
Optimal Power ◽  
Wide Range ◽  
Individual Taxon ◽  
The Individual

We previously developed LDM for testing hypotheses about the microbiome that performs the test at both the community level and the individual taxon level. LDM can be applied to relative abundance data and presence-absence data separately, which work well when associated taxa are abundant and rare, respectively. Here we propose an omnibus test based on LDM that allows simultaneous consideration of data at different scales, thus offering optimal power across scenarios with different association mechanisms. The omnibus test is available for the wide range of data types and analyses that are supported by LDM. The omnibus test has been added to the R package LDM, which is available on GitHub at https://github.com/yijuanhu/LDM .

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