Howlader A.M.,University of Ryukyus |
Urasaki N.,University of Ryukyus |
Yona A.,University of Ryukyus |
Senjyu T.,University of Ryukyus |
Saber A.Y.,Operation Technology Inc.
Renewable and Sustainable Energy Reviews | Year: 2013
Wind energy is inexhaustible renewable. Unlike conventional fossil fuels, wind energy is clean, abundant energy that will be available for future generations. However, wind speed is a highly stochastic component which can deviate very quickly. Output power of the wind energy conversion system (WECS) is proportional to the cube of wind speed, which causes the output power fluctuation of the wind turbine. The power fluctuation causes frequency fluctuation and voltage flicker inside the power grid. In order to reduce the power fluctuation, various approaches have been proposed in the last decades. This article deals with the review of several power smoothing strategies for the WECS. Power smoothing methods of the WECS are primarily separated into two categories such as energy storage based power smoothing method and without energy storage based power smoothing method. The main objectives of this paper are to introduce operating principles for different power smoothing methods. The energy storage based power smoothing method is effective but installation and maintenance costs of a storage device are very high. According to the literatures review, without energy storage based power smoothing method can reduce the cost of the WECS extensively. Various methods have been proposed to generate a smooth output power of the WECS without energy storage devices. Simulation results are compared among the available methods. From the review of simulation results, the kinetic energy of the inertia control method is the highly efficient power smoothing approach. © 2013 Elsevier Ltd.
Saber A.Y.,Operation Technology Inc.
International Journal of Electrical Power and Energy Systems | Year: 2012
This paper presents a novel modified particle swarm optimization (MPSO), which includes advantages of bacterial foraging (BF) and PSO for constrained dynamic economic dispatch (ED) problem. The proposed modified PSO consists of problem dependent four promising values in velocity vector to incorporate repellent advantage of bacterial foraging in PSO for the complex dynamic ED problem. It reliably and accurately tracks a continuously changing solution of the complex cost functions. As there is no differentiation operation in this method, all cost functions can easily be handled. The modified PSO has better balance between local and global search abilities and it can avoid local minima quickly. Finally, a benchmark data set and existing methods are used to show the effectiveness of the proposed method. © 2011 Elsevier Ltd. All rights reserved.
Operation Technology Inc. | Date: 2014-08-15
Systems and methods are provided for simulating fraction power and control in transportation systems under design conditions and/or utilizing real-time data.
Operation Technology Inc. | Date: 2010-08-30
A hold and drive tool and method of operation for fastening parts together with a stud and nut. The tool may comprise a tool body including a drive member therein, with the drive member rotationally driven by a power source; a nut drive member engaging the drive member and including a nut engaging portion received on the nut and rotating the nut relative to the stud; a hold member including a hold shaft connected to a hold bit, with the hold bit located in the nut drive member and received on a hold feature on the stud to prevent the stud from rotating relative to the hold member; and a clutch secured to the tool body and the hold shaft, with the clutch selectively allowing for and preventing rotation of the hold shaft relative to the tool body.
Operation Technology Inc. | Date: 2013-10-03
Generator dynamic model parameter estimation and tuning using online data and subspace state space models are disclosed. According to one embodiment, a system comprises a sensor, a data acquisition network in communication with the sensor; a user console and an identification and tuning engine in communication with the data acquisition network, the user console, and a database. The database comprises one or more generator models, and the identification and tuning engine identifies and tunes parameters associated with a selected generator model.
Operation Technology Inc. | Date: 2010-01-27
A torque transmitting device includes a first race, a second race, and a biasing member. The torque transmitting device selectively transmits a torque in a rotational direction between a first member and a second member. The second member includes a surface that defines an annular bore having a decreasing diameter in an axial direction. The second race opposes the first race and includes a surface that opposes the second member and has the decreasing diameter in the axial direction. The first race and the second race define a predetermined torque limit. The biasing element biases the second race against the second member with a predetermined force that contributes to a predetermined holding torque between the surface of the second race and the surface of the second member that is less than the predetermined torque limit.
Operation Technology Inc. | Date: 2010-07-06
A control system for an engine of a vehicle includes a shift forecasting module that forecasts one of an upshift and a downshift of a manual transmission based on vehicle acceleration, clutch pedal position, acceleration pedal position and brake pedal position. A gear state calculating module determines a current gear state based on a speed of the engine and a speed of the vehicle. A next gear state calculating module determines a next gear state. The next gear state is based on the current gear state and the one of the upshift and downshift. A next engine speed calculating module estimates an estimated engine speed based on the next gear state and the vehicle speed. An engine speed control module adjusts the engine speed based on the estimated engine speed.
Operation Technology Inc. | Date: 2013-09-30
Dynamic parameter tuning using particle swarm optimization is disclosed. According to one embodiment, a system for dynamically tuning parameters comprising a control unit; and a system for receiving parameters tuned by the control unit. The control unit receives as input a model selection and definitions, and dynamically tunes a value for each parameter by using a modified particle swarm optimization method. The modified particle swarm optimization method comprises moving particle locations based on a particles inertia, experience, global knowledge, and a tuning factor. The control unit outputs the dynamically tuned value for each parameter.
Operation Technology Inc. | Date: 2010-04-02
A method of controlling the temperature of a thermoelectric generator (TEG) in an exhaust system of an engine is provided. The method includes determining the temperature of the heated side of the TEG, determining exhaust gas flow rate through the TEG, and determining the exhaust gas temperature through the TEG. A rate of change in temperature of the heated side of the TEG is predicted based on the determined temperature, the determined exhaust gas flow rate, and the determined exhaust gas temperature through the TEG. Using the predicted rate of change of temperature of the heated side, exhaust gas flow rate through the TEG is calculated that will result in a maximum temperature of the heated side of the TEG less than a predetermined critical temperature given the predicted rate of change in temperature of the heated side of the TEG. A corresponding apparatus is provided.
News Article | April 30, 2015
DUBLIN--(BUSINESS WIRE)--Research and Markets (http://www.researchandmarkets.com/research/brfkqx/cybersecurity) has announced the addition of the "Cybersecurity Implications in the US Chemical Industry" report to their offering. As critical infrastructure industries move towards a more connected and integrated operating ecosystem, it becomes crucial for end users to focus on the expanding threat surface areas. This research service identifies the emerging trends and evolving business models for cybersecurity in the US chemical industry. It was developed based on a series of moderated online discussion boards with participants in the power, chemicals and petrochemicals, and oil and gas industries. The study examines the current state of cybersecurity preparedness, as well as best practices, unmet needs, and industry challenges in the chemical manufacturing and processing, storage, and transportation segments. Solutions will have to develop and follow Standard Operating Procedures (SOP) for routine functions such as backups, antivirus, user management, remote system access, removable media use, and access policy. Vendors will have to certify compliance with cybersecurity standards and include the tests as part of their Factory Acceptance Testing (FAT). Operating systems will need to evolve to the point where they do not operate in silos. The industry will move towards a lifecycle model to manage control systems and safety systems. IT and OT will need to improve communication and awareness of the different requirements for each platform. Operational safety and information confidentiality are key factors driving cybersecurity investments. However, there is still an imbalance between the world of Information Technology (IT) and Operation Technology (OT). Security intelligence, hot patching, intellectual property protection, penetration testing, and device control systems are frequently used technologies. The industry is slowly moving from a reactive approach to a proactive approach. 10. Conclusions and Future Outlook - Cybersecurity in the Chemical Industry