247 research outputs found
Bonny Black Bess
No full textDick Turpin\u27s love for his Horse, Bonny Black Bess, and her incredible speedhttps://egrove.olemiss.edu/kgbsides_uk/1972/thumbnail.jp
Highly Compact Partial Power Converter for a Highly Efficient PV-BESS Stacked Generation System
No full textThe inherently intermittent nature of photovoltaic (PV) energy has brought increasing interest towards the integration between PV sources and Battery Energy Storage Systems (BESS). In this paper, a Series Partial Power Processing (PPP) converter based on Capacitive Power Transfer (CPT) is proposed to integrate PV and BESS in a grid-connected inverter system. The proposed converter has been simulated according to a PV string capable to provide 1430 W under full irradiance conditions, a BESS nominal voltage equal to 215 V and a solar inverter assumed to operate with a minimum voltage of 150 V and a maximum current of 10 A. Simulation tests carried out at different conditions of solar radiation and required load power aim at demonstrating the correct operation of the proposed system.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.DC systems, Energy conversion & Storag
The Bookshelf for Boys and Girls, Volume 2
No full textSixteen fables of Aesop and a few other fables start off this volume. The editor of these versions is not acknowledged. The illustrations are a third set for Aesop by Kurt Wiese (Favorite Stories, 1942; Jacobs' The Fables of Aesop, 1950/62). The frontispiece is a strong full-page colored depiction of FC by Bess B. Cleveland. I believe that I have seen it somewhere else as frontispiece, but I cannot place it. Compare the smaller version of the same illustration in The Home University Bookshelf, Volume III, 380 (1945). See the identical new edition of 1970/81.This is a hardbound book (hard cover)Editorial Board of the University Societ
The Home University Bookshelf.
No full textFables of Aesop are on 364-88. Some curious tellings: the monkey seizes the cat's paws and makes her grab the hot nuts, and the moral of FG is Disappointment may be lightened by philosophy, even if the latter is wrong. A curious melange of illustrations: four nice colored illustrations to a page by Bess Bruce Cleveland in addition to the black-and-whites on the pages themselves (which look copied). Aesop is followed by fables of India, Gay, La Fontaine, and others. Also check 257-74: this Japanese and Other Oriental Tales section includes The Story of Zirac and other fable material. See the nearly identical edition of 1945.This is a hardbound book (hard cover)Editorial Board of the University Societ
Optimising BESS Control Strategies for Congestion and Price Arbitrage
No full textRenewable energy generation projects are often measured by their peak capacity. A wind farm rated at 25 MW will generate 25 MW of power under the right circumstances. This peak capacity is reached very little in practice. However, these generators are forced to purchase grid operation infrastructure that can handle this peak generation event. The high voltage grid connections are expensive and increasingly difficult to receive permits for. This work presents a solution in which the high voltage grid connection is undersized in comparison to the renewable energy generator. A battery energy storage system is installed in the local grid to solve the issue of excess energy generation (congestion).A simulation of the local network has been built that models a battery energy storage system (BESS), the network and uses data from a solar park. A case study in which a 19 MW solar park is connected to the high voltage grid with a transformer of only 14 MW as well as a 14 MW | 30 MWh BESS on the network is investigated in the rest of the work. Furthermore a BESS control strategy for price arbitrage on the TenneT imbalance market is presented and encoded such that it can be optimised.Four heuristics are presented that time and size the congestion issue in a manner the control strategy of the BESS can prepare for and solve congestion when necessary. These heuristics are tested against strategies optimized for revenue maximisation through price arbitrage. While the most aggressive strategies did not solve all the congestion events in these simulations, we found that the heuristic that takes the average generation of the solar park into account performs the best while remaining appropriately conservative.A basic evolutionary algorithm is presented that optimizes a BESS control strategy for price arbitrage when the BESS is not needed on the local network to solve congestion. Although the strategies earn ~33% less revenue due to the congestion related limitations, the optimisation surrounding congestion does improve revenue by 2.58%.The results presented in this work suggest that this setup of a local grid can be economically viable and that the BESS can solve the congestion issue when steered with an appropriate control strategy. We hope to inspire parties that battery energy storage systems can earn substantial revenue aside from solving issues on a (local) grid.Computer Scienc
The Home University Bookshelf Vol 3:
No full textSee the nearly identical edition of 1927. Here the cover has a picture, but the endpapers have lost most of their colors. The fables of Aesop are on 364-88. Some curious tellings: the monkey seizes the cat's paws and makes her grab hot nuts, and the moral of FG is Disappointment may be lightened by philosophy, even if the latter is wrong. A curious melange of illustrations: four good colored illustrations (particularly good in this edition) to a page by Bess Bruce Cleveland in addition to the black-and-whites (which look copied) on the text-pages themselves. Aesop is followed by fables of India, Gay, La Fontaine, and others. Also check 257-74: this Japanese and Other Oriental Tales section includes The Story of Zirac and other fable material.This is a hardbound book (hard cover)Editorial Board of the University Societ
Experimental Behavior of Skewed Cast-in-Place Concrete Box Culverts
No full textCast-in-place reinforced concrete box culverts are widely used for roadway drainage and are the most common type of bridge in many states. The current culvert design methodology is performed in accordance with the AASHTO LRFD Bridge Design Specifications. However, there is no specific guidance for skewed culverts, where the culvert and roadway centerlines are not perpendicular. Due to the lack of explicit provisions for skewed culverts, state departments of transportation (DOTs) adopt conservative design practices and vary extensively, highlighting the need for consistent design approaches. This study investigates the structural effects of skew angle on cast-in-place concrete box culverts through full-scale laboratory tests.
Three culvert specimens with 10 foot clear spans, identical reinforcement layouts, and skew angles of 0 degrees (control), 30 degrees, and 60 degrees were constructed and tested under simulated vehicular loading. Experimental results revealed that the skew angle had minimal impact on the overall stiffness, service-level behavior, and ultimate strength of the culvert. All specimens displayed nearly rigid slab-to-wall joint behavior, validating rigid assumptions commonly used in analysis. Cracking was not observed at service design load levels, and ultimate load capacities significantly exceeded AASHTO LRFD requirements. The skewed culverts exhibited beneficial two-way bending behavior, engaging both longitudinal slab reinforcement and integral parapet beams, enhancing load distribution. Differences in failure modes emerged at high skew angles, transitioning from beam shear failures at 0° and 30° to slab punching shear at 60°, highlighting the importance of detailing in highly skewed configurations.
This research demonstrates that current conservative practices, such as doubling reinforcement at skewed regions, are unnecessary. A standard, uniform reinforcement design adequately meets structural demands for skewed culverts, offering DOTs opportunities to optimize designs and achieve significant material and cost savings without compromising structural performance
Modelling and performance analysis of an integrated control system for providing ancillary services using a BESS
No full textThe production and consumption of energy in all walks of life is moving towards a greener and more sustainable mix of energy sources away from the traditional sources of coal and gas. With this shift, more renewable energy is expected to be integrated into the grid replacing conventional synchronous generators. In such conditions, the stability of the grid becomes a major concern due to the lack of inertia with the loss of base load generators. As a result, there is an urgent need to develop flexible solutions like Battery Energy Storage System (BESS) to provide ancillary services. Current research tackles it with a piecemeal approach towards frequency and voltage stability. As a result, different types of controllertopology are currently used to get each electrical parameter within the acceptable tolerance limits The contribution of this paper is to build an integrated controller based on droop control to tackle the two parameters of voltage and frequency stability simultaneously with one controller in a holistic fashion. To achieve this goal of demonstrating integrated control, different control schemes were tested and compared in terms of performance with respect to frequency control. The application of the above mentioned integrated control in a decentralized controller environment like a virtual power plant (VPP) was also demonstrated. The testing and design of the control schemes and BESS was done via benchmark models built for real time digital simulation (RTDS). The results show that the control schemes employed in the BESS can effectively contribute towards providing ancillary services in a holistic manner.Electrical Engineerin
Evaluation of Battery Performance in MMC based BESS
No full textabstract: Li-ion batteries are being used on a large scale varying from consumer electronics to electric vehicles. The key to efficient use of batteries is implementing a well-developed battery management system. Also, there is an opportunity for research for improving the battery performance in terms of size and capacity. For all this it is imperative to develop Li-ion cell model that replicate the performance of a physical cell unit. This report discusses a dual polarization cell model and a battery management system implemented to control the operation of the battery. The Li-ion cell is modelled, and the performance is observed in PLECS environment.
The main aspect of this report studies the viability of Li-ion battery application in Battery Energy Storage System (BESS) in Modular multilevel converter (MMC). MMC-based BESS is a promising solution for grid-level battery energy storage to accelerate utilization and integration of intermittent renewable energy resources, i.e., solar and wind energy. When the battery units are directly integrated in submodules (SMs) without dc-dc interfaced converters, this configuration provides highest system efficiency and lowest cost. However, the lifetime of battery will be affected by the low-frequency components contained in arm currents, which has not been thoroughly investigated. This paper investigates impact of various low-frequency arm-current ripples on lifetime of Li-ion battery cells and evaluate performance of battery charging and discharging in an MMC-BESS without dc-dc interfaced converters.Dissertation/ThesisMasters Thesis Electrical Engineering 201
Optimal Battery Energy Storage System Sizing for Demand Charge Management in EV Fast Charging Stations
No full textThe high pulsating demand of fast charging stations (FCS) may cause monthly demand charges to account for a significant fraction of a station's electric bill. To reduce these costs, demand charge management can be applied to suppress peak power demands at FCSs, also using battery energy storage systems (BESS). This paper proposes a multi-objective approach for the optimal BESS and grid-tie sizing in FCS designs using genetic algorithms. With demand data from a FCS in the Netherlands, numerical studies are conducted in the Mosaik and Pymoo environments to assess the effectiveness of the proposed formulation.Accepted author manuscriptDC systems, Energy conversion & Storag
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