Harmonic Resonance Damping with a Hybrid Compensation System in Power Systems with Dispersed Generation

DEFF Research Database (Denmark)

Chen, Zhe; Pedersen, John Kim; Blaabjerg, Frede

2004-01-01

A hybrid compensation system consisting of an active filter and a group of distributed passive filters has been studied previously. The passive filters are used for each distorting load or Dispersed Generation (DG) unit to remove major harmonics and provide reactive power compensation. The active...... filter is connected in parallel with the distributed passive filters and loads/DGs to correct the system unbalance and remove the remaining harmonic components. The effectiveness of the presented compensation system has also been demonstrated. This paper studies the performance of the hybrid compensation...... demonstrated that the harmonic resonance can be damped effectively. The hybrid filter system is an effective compensation system for dispersed generation systems. In the compensation system, the passive filters are mainly responsible for main harmonic and reactive power compensation of each individual load/ DG...

Coherent interference effects and squeezed light generation in optomechanical systems

Science.gov (United States)

Qu, Kenan

My Ph.D. dissertation is on the fundamental effects in optomechanical systems (OMS) and their important applications. The OMS are based on the possibility of the mechanical motion produced by few photons incident on the mechanical device. This dissertation presents several applications of the OMS in the area of storage of light in long-lived phonons, single mode optomechanical Ramsey interferometry, and generation of large amount of squeezing in the output radiation. The long-lived phonons can be monitored and controlled via optical means as was experimentally demonstrated. To show this, I develop the theory of transient electromagnetically induced transparency (EIT). For further applications like state transfer, especially over very different frequency regimes, I consider double-cavity OMS, where the two cavities can correspond to different spectral domains, yet the state transfer is possible via phonons. The state transfer is based on a new effect, electromagnetically induced absorption (EIA), where one uses a second control field from the other cavity to produce an absorption peak inside the EIT window. All these involve the interference of various path ways via which a final state is reached. The following chapter shows how Fano-like interference can arise in OMS. A Fano asymmetry parameter for OMS was defined. The last two chapters deal with the question if OMS can be efficient generators of squeezed light. I show by blue and red tuning the two cavities in a double-cavity OMS, one can generate effectively a two-mode parametric interaction which yields two-mode squeezed output with the squeezing magnitude of the order of 10dB. This requires a bath temperature of 10mK. Such temperatures obtained by using Helium dilution refrigerator are routinely used with superconducting OMS. The major part of this dissertation is devoted to the dispersive optomechanical interaction. However, the interaction can also be dissipative, where the mechanical displacement modulates

EFFECTS OF IMPLEMENTATION OF CO-GENERATION IN THE DISTRICT HEATING SYSTEM OF THE FACULTY OF MECHANICAL ENGINEERING IN NIŠ

Directory of Open Access Journals (Sweden)

Mladen M Stojiljković

2010-01-01

Full Text Available Implementation of co-generation of thermal and electrical energy in district heating systems often results with higher overall energy efficiency of the systems, primary energy savings and environmental benefits. Financial results depend on number of parameters, some of which are very difficult to predict. After introduction of feed-in tariffs for generation of electrical energy in Serbia, better conditions for implementation of co-generation are created, although in district heating systems barriers are still present. In this paper, possibilities and effects of implementation of natural gas fired co-generation engines are examined and presented for the boiler house that is a part of the district heating system owned and operated by the Faculty of Mechanical Engineering in Niš. At the moment, in this boiler house only thermal energy is produced. The boilers are natural gas fired and often operate in low part load regimes. The plant is working only during the heating season. For estimation of effects of implementation of co-generation, referent values are taken from literature or are based on the results of measurements performed on site. Results are presented in the form of primary energy savings and greenhouse gasses emission reduction potentials. Financial aspects are also considered and triangle of costs is shown.

Electricity generating system. [Wind/diesel/flywheel system

Energy Technology Data Exchange (ETDEWEB)

Moody, R.L.

1992-02-05

An electricity generating system is described which includes a water tank with electric heating elements connected to the water cooling system of a diesel engine which is heated by excess output of the system. Power in excess of that required by a load which is generated by a wind turbine driven generator runs up a flywheel and further excess is absorbed in the tank. A fan associated with a radiator connected to the tank may be operated to dissipate further excess power. When the load requirements exceed the output of the generators linked to the wind turbine and the flywheel the engine operates a synchronous alternator. (author).

Power system for tokamak fusion experiments. Motor generator with flywheel effect

International Nuclear Information System (INIS)

Miyachi, Kengo

1997-01-01

JT-60 requires an enormous electric power pulse about 1,300 MVA periodically for its plasma initiation, containment and heating. JT-60 could not receive all electric power from a commercial line for plasma experiment except about 160 MVA because the 275 kV commercial line has some limitations. Therefore JT-60 needs huge electric power sources. The power supply system of JT-60 has 3 motor generators (MG). The total capacity of MG is 1,115 MVA that consists of a toroidal MG (TMG), poloidal MG (PMG) and Heating power supply MG (HMG), and each MG has a huge flywheel effect. For example, TMG has a 4.02 GJ energy yield that consists of 6 disk flywheel. The total weight of flywheel of TMG is 650 ton. This report describes the structure, operating system, and maintenance history of 3 types of MG. (author)

Dispersed solar thermal generation employing parabolic dish-electric transport with field modulated generator systems

Science.gov (United States)

Ramakumar, R.; Bahrami, K.

1981-01-01

This paper discusses the application of field modulated generator systems (FMGS) to dispersed solar-thermal-electric generation from a parabolic dish field with electric transport. Each solar generation unit is rated at 15 kWe and the power generated by an array of such units is electrically collected for insertion into an existing utility grid. Such an approach appears to be most suitable when the heat engine rotational speeds are high (greater than 6000 r/min) and, in particular, if they are operated in the variable speed mode and if utility-grade a.c. is required for direct insertion into the grid without an intermediate electric energy storage and reconversion system. Predictions of overall efficiencies based on conservative efficiency figures for the FMGS are in the range of 25 per cent and should be encouraging to those involved in the development of cost-effective dispersed solar thermal power systems.

System Dynamics Simulation of Large-Scale Generation System for Designing Wind Power Policy in China

Directory of Open Access Journals (Sweden)

Linna Hou

2015-01-01

Full Text Available This paper focuses on the impacts of renewable energy policy on a large-scale power generation system, including thermal power, hydropower, and wind power generation. As one of the most important clean energy, wind energy has been rapidly developed in the world. But in recent years there is a serious waste of wind power equipment and investment in China leading to many problems in the industry from wind power planning to its integration. One way overcoming the difficulty is to analyze the influence of wind power policy on a generation system. This paper builds a system dynamics (SD model of energy generation to simulate the results of wind energy generation policies based on a complex system. And scenario analysis method is used to compare the effectiveness and efficiency of these policies. The case study shows that the combinations of lower portfolio goal and higher benchmark price and those of higher portfolio goal and lower benchmark price have large differences in both effectiveness and efficiency. On the other hand, the combinations of uniformly lower or higher portfolio goal and benchmark price have similar efficiency, but different effectiveness. Finally, an optimal policy combination can be chosen on the basis of policy analysis in the large-scale power system.

Power Quality Improvements in Wind Diesel Power Generation System

Directory of Open Access Journals (Sweden)

Omar Feddaoui

2015-08-01

Full Text Available Generation of electricity using diesel is costly for small remote isolated communities. At remote location electricity generation from renewable energy such as wind can help reduce the overall operating costs by reducing the fuel costs. However, the penetration of wind power into small diesel-based grids is limited because of its effect on power quality and reliability. This paper focuses on the combination of Wind Turbine and Diesel Generator systems for sustained power generation, to improve the power quality of wind generation system. The performances of the optimal control structure are assessed and discussed by means of a set of simulations.

A Pilot Study on Comparative Assessment of Electricity Generating Systems Using Monetary Value

International Nuclear Information System (INIS)

Kim, Kil Yoo; Kim, Seong Ho; Kim, Tae Woon

2005-01-01

Recently, many variables which affect the cost of electricity generating systems are drastically changing. For examples, the price of crude oil soared above 70 dollars a barrel and it will be continuously going up. Kyoto Protocol, an international agreement signed by 141 countries that promise to reduce greenhouse gases, finally entered into force on February 16, 2005. A total of 39 countries are required to reduce their emissions of greenhouse gases, including carbon dioxide, methane and nitrous oxide, to 5.2 percent below the 1990 levels during 2008-2012. Also, many researches and government support are concentrated on the renewable energy. In Korea, the portion of renewable energy in the electricity generation will be increased up to 7% in 2010. Therefore, a comparative assessment among electricity generating systems by considering the environmental impacts, risks, health effects, and social effects is required to establish the national energy and power systems planning systematically and scientifically. Up to now, several papers for data collection and analysis of the environmental impacts, risks, and health effects for various electricity generation systems in Korea were published. However, they were not the comparative assessment covering all impacts and effects but just a partial assessment (e.g., environmental impacts assessment only), or not covering all generating systems such as nuclear, coal, LNG, hydro, oil, wind, photo-voltaic (=solar) but covering partial ones (e.g., nuclear, coal, LNG, and wind only). Although Ref. deals all electricity generating systems, and all impacts such as economic, environmental, health, and social impacts, it used too much subjective opinion by using pairwise comparison questionnaire to know the relative importance among the economic, environmental, health, and social effects. However, if economic, environmental, health, and social effects of the various electricity generation systems could be calculated by monetary value

Trends in Wind Turbine Generator Systems

DEFF Research Database (Denmark)

Polinder, Henk; Ferreira, Jan Abraham; Jensen, Bogi Bech

2013-01-01

This paper reviews the trends in wind turbine generator systems. After discussing some important requirements and basic relations, it describes the currently used systems: the constant speed system with squirrel-cage induction generator, and the three variable speed systems with doubly fed...... induction generator (DFIG), with gearbox and fully rated converter, and direct drive (DD). Then, possible future generator systems are reviewed. Hydraulic transmissions are significantly lighter than gearboxes and enable continuously variable transmission, but their efficiency is lower. A brushless DFIG...

Evaluation of a continuous-positive pressure generating system

Directory of Open Access Journals (Sweden)

Herrera N

2016-03-01

Full Text Available Nestor Herrera,1,2 Roberto Regnícoli,1,2 Mariel Murad1,2 1Neonatology Unit, Italian Hospital Garibaldi, Rosario, Argentina; 2Experimental Medicine and Surgery Unit, Italian University Institute of Rosario, Argentina Abstract: The use of systems that apply continuous-positive airway pressure by means of noninvasive methods is widespread in the neonatal care practice and has been associated with a decrease in the use of invasive mechanical ventilation, less administration of exogenous surfactant, and bronchopulmonary dysplasia. Few experimental studies on the functioning of the neonatology systems that generate continuous-positive airway pressure have been reported. A flow resistor system associated with an underwater seal resistor in a lung test model was described, and it was compared with an underwater seal threshold resistor system. Important differences in the pressures generated in the different systems studied were verified. The generation of pressure was associated with the immersion depth and the diameter of the bubble tubing. The flow resistor associated with an underwater seal, with small bubble tubing, showed no important differences in the evaluated pressures, exerting a stabilizing effect on the generated pressures. The importance of measuring the pressure generated by the different systems studied was verified, due to the differences between the working pressures set and the pressures measured. Keywords: continuous-positive pressure, flow and threshold resistor, BCPAP

Power quality improvement of unbalanced power system with distributed generation units

DEFF Research Database (Denmark)

Hu, Y.; Chen, Zhe; Excell, P.

2011-01-01

This paper presents a power electronic system for improving the power quality of the unbalanced distributed generation units in three-phase four-wire system. In the system, small renewable power generation units, such as small PV generator, small wind turbines may be configured as single phase...... and control of the converter are described. Simulation results have demonstrated that the system can effectively correct the unbalance and enhance the system power quality....... generation units. The random nature of renewable power sources may result in significant unbalance in the power network and affect the power quality. An electronic converter system is proposed to correct the system unbalance and harmonics so as to deal with the power quality problems. The operation...

A Comparison of Electricity Generation System Sustainability among G20 Countries

Directory of Open Access Journals (Sweden)

Jinchao Li

2016-12-01

Full Text Available Planning for electricity generation systems is a very important task and should take environmental and economic factors into account. This paper reviews the existing metrics and methods in evaluating energy sustainability, and we propose a sustainability assessment index system. The input indexes include generation capacity, generation cost, and land use. The output indexes include desirable and undesirable parts. The desirable outputs are total electricity generation and job creation. The undesirable outputs are external supply risk and external costs associated with the environment and health. The super-efficiency data envelopment analysis method is used to calculate the sustainability of electricity generation systems of 23 countries from 2005 to 2014. The three input indexes and three undesirable output indexes are used as the input variables. The two desirable outputs are used as the output variables. The results show that most countries’ electricity generation sustainability values have decreasing trends. In addition, nuclear and hydro generation have positive effects. Solar, wind, and fossil fuel generation have negative effects on sustainability.

Application of cultural algorithm to generation scheduling of hydrothermal systems

International Nuclear Information System (INIS)

Yuan Xiaohui; Yuan Yanbin

2006-01-01

The daily generation scheduling of hydrothermal power systems plays an important role in the operation of electric power systems for economics and security, which is a large scale dynamic non-linear constrained optimization problem. It is difficult to solve using traditional optimization methods. This paper proposes a new cultural algorithm to solve the optimal daily generation scheduling of hydrothermal power systems. The approach takes the water transport delay time between connected reservoirs into consideration and can conveniently deal with the complicated hydraulic coupling simultaneously. An example is used to verify the correctness and effectiveness of the proposed cultural algorithm, comparing with both the Lagrange method and the genetic algorithm method. The simulation results demonstrate that the proposed algorithm has rapid convergence speed and higher solution precision. Thus, an effective method is provided to solve the optimal daily generation scheduling of hydrothermal systems

Dynamic analysis of floating wave energy generation system with mooring system

International Nuclear Information System (INIS)

Choi, Gyu Seok; Sohn, Jeong Hyun

2013-01-01

In this study, dynamic behaviors of a wave energy generation system (WEGS) that converts wave energy into electric energy are analyzed using multibody dynamics techniques. Many studies have focused on reducing the effects of a mooring system on the motion of a WEGS. Several kinematic constraints and force elements are employed in the modeling stage. Three dimensional wave load equations are used to implement wave loads. The dynamic behaviors of a WEGS are analyzed under several wave conditions by using MSC/ADAMS, and the rotating speed of the generating shaft is investigated for predicting the electricity capacity. The dynamic behaviors of a WEGS with a mooring system are compared with those of a WEGS without a mooring system. Stability evaluation of a WEGS is carried out through simulation under extreme wave load

A novel HTS SMES application in combination with a permanent magnet synchronous generator type wind power generation system

Energy Technology Data Exchange (ETDEWEB)

Kim, G.H.; Kim, A.R.; Kim, S. [Changwon National University, 9 Sarim-dong, Changwon 641-773 (Korea, Republic of); Park, M., E-mail: paku@changwon.ac.kr [Changwon National University, 9 Sarim-dong, Changwon 641-773 (Korea, Republic of); Yu, I.K. [Changwon National University, 9 Sarim-dong, Changwon 641-773 (Korea, Republic of); Seong, K.C. [Superconducting Device and Cryogenics Group, Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of); Won, Y.J. [Korea Electric Power Corporation, Changwon 641-241 (Korea, Republic of)

2011-11-15

A novel connection topology of SMES is proposed in this paper. Structure of the proposed system is cost-effective because it reduces a converter. The proposed system smoothens output power of wind power generation system. Advantage of the system is to improve the low voltage ride through capability. Superconducting magnetic energy storage (SMES) system is a DC current driven device and can be utilized to improve power quality particularly in connection with renewable energy sources due to higher efficiency and faster response than other devices. This paper suggests a novel connection topology of SMES which can smoothen the output power flow of the wind power generation system (WPGS). The structure of the proposed system is cost-effective because it reduces a power converter in comparison with a conventional application of SMES. One more advantage of SMES in the proposed system is to improve the capability of low voltage ride through (LVRT) for the permanent magnet synchronous generator (PMSG) type WPGS. The proposed system including a SMES has been modeled and analyzed by a PSCAD/EMTDC. The simulation results show the effectiveness of the novel SMES application strategy to not only mitigate the output power of the PMSG but also improve the capability of LVRT for PMSG type WPGS.

A novel HTS SMES application in combination with a permanent magnet synchronous generator type wind power generation system

International Nuclear Information System (INIS)

Kim, G.H.; Kim, A.R.; Kim, S.; Park, M.; Yu, I.K.; Seong, K.C.; Won, Y.J.

2011-01-01

A novel connection topology of SMES is proposed in this paper. Structure of the proposed system is cost-effective because it reduces a converter. The proposed system smoothens output power of wind power generation system. Advantage of the system is to improve the low voltage ride through capability. Superconducting magnetic energy storage (SMES) system is a DC current driven device and can be utilized to improve power quality particularly in connection with renewable energy sources due to higher efficiency and faster response than other devices. This paper suggests a novel connection topology of SMES which can smoothen the output power flow of the wind power generation system (WPGS). The structure of the proposed system is cost-effective because it reduces a power converter in comparison with a conventional application of SMES. One more advantage of SMES in the proposed system is to improve the capability of low voltage ride through (LVRT) for the permanent magnet synchronous generator (PMSG) type WPGS. The proposed system including a SMES has been modeled and analyzed by a PSCAD/EMTDC. The simulation results show the effectiveness of the novel SMES application strategy to not only mitigate the output power of the PMSG but also improve the capability of LVRT for PMSG type WPGS.

Techno-Economic Feasibility of Highly Efficient Cost-Effective Thermoelectric-SOFC Hybrid Power Generation Systems

Energy Technology Data Exchange (ETDEWEB)

Jifeng Zhang; Jean Yamanis

2007-09-30

Solid oxide fuel cell (SOFC) systems have the potential to generate exhaust gas streams of high temperature, ranging from 400 to 800 C. These high temperature gas streams can be used for additional power generation with bottoming cycle technologies to achieve higher system power efficiency. One of the potential candidate bottoming cycles is power generation by means of thermoelectric (TE) devices, which have the inherent advantages of low noise, low maintenance and long life. This study was to analyze the feasibility of combining coal gas based SOFC and TE through system performance and cost techno-economic modeling in the context of multi-MW power plants, with 200 kW SOFC-TE module as building blocks. System and component concepts were generated for combining SOFC and TE covering electro-thermo-chemical system integration, power conditioning system (PCS) and component designs. SOFC cost and performance models previously developed at United Technologies Research Center were modified and used in overall system analysis. The TE model was validated and provided by BSST. The optimum system in terms of energy conversion efficiency was found to be a pressurized SOFC-TE, with system efficiency of 65.3% and cost of $390/kW of manufacturing cost. The pressurization ratio was approximately 4 and the assumed ZT of the TE was 2.5. System and component specifications were generated based on the modeling study. The major technology and cost barriers for maturing the system include pressurized SOFC stack using coal gas, the high temperature recycle blowers, and system control design. Finally, a 4-step development roadmap is proposed for future technology development, the first step being a 1 kW proof-of-concept demonstration unit.

Magnetohydrodynamic generator and pump system

International Nuclear Information System (INIS)

Birzvalk, Yu.A.; Karasev, B.G.; Lavrentyev, I.V.; Semikov, G.T.

1983-01-01

The MHD generator-pump system, or MHD coupling, is designed to pump liquid-metal coolant in the primary circuit of a fast reactor. It contains a number of generator and pump channels placed one after another and forming a single electrical circuit, but hydraulically connected parallel to the second and first circuits of the reactor. All the generator and pump channels are located in a magnetic field created by the magnetic system with an excitation winding that is fed by a regulated direct current. In 500 to 2000 MW reactors, the flow rate of the coolant in each loop of the primary circuit is 3 to 6 m 3 /s and the hydraulic power is 2 to 4 MW. This paper examines the primary characteristics of an MHD generator-pump system with various dimensions and number of channels, wall thicknesses, coolant flow rates, and magnetic fields. It is shown that its efficiency may reach 60 to 70%. The operating principle of the MHD generator-pump system is explained in the referenced patent and involves the transfer of hydraulic power from generator channels to pump channels using a magnetic field and electrical circuit common to both channels. Variations of this system may be analyzed using an equivalent circuit. 7 refs., 5 figs

Effect of working fluids on the performance of a novel direct vapor generation solar organic Rankine cycle system

International Nuclear Information System (INIS)

Li, Jing; Alvi, Jahan Zeb; Pei, Gang; Ji, Jie; Li, Pengcheng; Fu, Huide

2016-01-01

Highlights: • A novel, flexible direct vapor generation solar ORC is proposed. • Technical feasibility of the system is discussed. • Fluid effect on collector efficiency is explored. • The system is more efficient than solar ORC with HTF. - Abstract: A novel solar organic Rankine cycle (ORC) system with direct vapor generation (DVG) is proposed. A heat storage unit is embedded in the ORC to guarantee the stability of power generation. Compared with conventional solar ORCs, the proposed system avoids the secondary heat transfer intermediate and shows good reaction to the fluctuation of solar radiation. The technical feasibility of the system is discussed. Performance is analyzed by using 17 dry and isentropic working fluids. Fluid effects on the efficiencies of ORC, collectors and the whole system are studied. The results indicate that the collector efficiency generally decreases while the ORC and system efficiencies increase with the increment in fluid critical temperature. At evaporation temperature of 120 °C and solar radiation of 800 Wm −2 , the ORC, collector and overall thermal efficiencies of R236fa are 10.59, 56.14 and 5.08% while their values for Benzene are 12.5, 52.58 and 6.57% respectively. The difference between collector efficiencies using R236fa and Benzene gets larger at lower solar radiation. The heat collection is strongly correlated with latent and sensible heat of the working fluid. Among the fluids, R123 exhibits the highest overall performance and seems to be suitable for the proposed system in the short term.

Effects of spontaneously generated coherence on the group velocity in a V system

International Nuclear Information System (INIS)

Bai Yanfeng; Guo Hong; Han, Dingan; Sun Hui

2005-01-01

We show how the application of an incoherent pumping can produce a variety of effects on the propagation of a weak electromagnetic pulse in a V system with spontaneously generated coherence (SGC). There exists an incoherent pumping rate which makes the group velocity reach the extremum near the region of two-photon resonant excitation. The existence of SGC is just the cause for the occurrence of the extremum, and it may also be regarded as a knob which can be used to manipulate light propagation from subluminal to superluminal

Design of improved fuel cell controller for distributed generation systems

Energy Technology Data Exchange (ETDEWEB)

Olsen Berenguer, F.A. [Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste, 1109, J5400ARL San Juan (Argentina); Molina, M.G. [CONICET, Instituto de Energia Electrica, Universidad Nacional de San Juan, Av. Libertador San Martin Oeste, 1109, J5400ARL San Juan (Argentina)

2010-06-15

The world has been undergoing a deregulation process which allowed competition in the electricity generation sector. This situation is bringing the opportunity for electricity users to generate power by using small-scale generation systems with emerging technologies, allowing the development of distributed generation (DG). A fuel cell power plant (FCPP) is a distributed generation technology with a rapid development because it has promising characteristics, such as low pollutant emissions, silent operation, high efficiency and long lifetime because of its small number of moving parts. The power conditioning system (PCS) is the interface that allows the effective connection to the electric power system. With the appropriate topology of the PCS and its control system design, the FCPP unit is capable of simultaneously performing both instantaneous active and reactive power flow control. This paper describes the design and implementation of a novel high performance PCS of an FCPP and its controller, for applications in distributed generation systems. A full detailed model of the FCPP is derived and a new three-level control scheme is designed. The dynamic performance of the proposed system is validated by digital simulation in SimPowerSystems (SPS) of MATLAB/Simulink. (author)

Three essays on the effect of wind generation on power system planning and operations

Science.gov (United States)

Davis, Clay Duane

While the benefits of wind generation are well known, some drawbacks are still being understood as wind power is integrated into the power grid at increasing levels. The primary difference between wind generation and other forms of generation is the intermittent, and somewhat unpredictable, aspect of this resource. The somewhat uncontrollable aspect of wind generation makes it important to consider the relationship between this resource and load, and also how the operation of other non-wind generation resources may be affected. The three essays that comprise this dissertation focus on these and other important issues related to wind generation; leading to an improved understanding of how to better plan for and utilize this resource. The first essay addresses the cost of increased levels of installed wind capacity from both a capacity planning and economic dispatch perspective to arrive at the total system cost of installing a unit of wind capacity. This total includes not only the cost of the wind turbine and associated infrastructure, but also the cost impact an additional unit of wind capacity has on the optimal mix and operation of other generating units in the electricity supply portfolio. The results of the model showed that for all wind expansion scenarios, wind capacity is not cost-effective regardless of the level of the wind production tax credit and carbon prices that were considered. Larger levels of installed wind capacity result in reduced variable cost, but this reduction is not able to offset increases in capital cost, as a unit of installed wind capacity does not result in an equal reduction in other non-wind capacity needs. The second essay develops a methodology to better handle unexpected short term fluctuations in wind generation within the existing power system. The methodology developed in this essay leads to lower expected costs by anticipating and planning for fluctuations in wind generation by focusing on key constraints in the system. The

Practical system for generating digital mixed reality video holograms.

Science.gov (United States)

Song, Joongseok; Kim, Changseob; Park, Hanhoon; Park, Jong-Il

2016-07-10

We propose a practical system that can effectively mix the depth data of real and virtual objects by using a Z buffer and can quickly generate digital mixed reality video holograms by using multiple graphic processing units (GPUs). In an experiment, we verify that real objects and virtual objects can be merged naturally in free viewing angles, and the occlusion problem is well handled. Furthermore, we demonstrate that the proposed system can generate mixed reality video holograms at 7.6 frames per second. Finally, the system performance is objectively verified by users' subjective evaluations.

Report on achievements in fiscal 1998. Development of technologies to put photovoltaic power generation systems into practical use - Demonstrative research on photovoltaic power generation system (Research on multi-hybrid photovoltaic power generation system); 1998 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyoko hatsuden system no jissho kenkyu (taiyoko hatsuden multi hybrid system no kenkyu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

A multi-hybrid system integrating photovoltaic and wind power generation systems with the existing diesel engine power generation system was assumed for installation in power systems in islands. System analyzing simulation and economic performance analyses were performed to consider system configurations suitable for islands from the viewpoints of system stability and economic performance. The work was progressed by dividing the subject into (1) research on the system configurations, and (2) studies on the economic performance. In performing either work, the power demand was classified as large (in Miyako Island), medium (in Kume Island) and small (in Tarama Island), and the introduction years into 1997, 2000, and 2005. In Item (1), the system parameter specifications were put into order, and the system analyzing simulation was performed, wherein it was verified that the system will be stabilized by introducing a system stabilizing equipment (batteries and an inverter) and by limiting the output from the wind power generation. In Item (2), it was made clear that the power generation cost is equivalent to or lower than the present cost, making reduction in fuel consumption possible. It was also disclosed that the introduction is most effective in small islands, and drop in the power generation amount due to limiting the output from the wind power generation is small. (NEDO)

An Integrated Safety Assessment Methodology for Generation IV Nuclear Systems

International Nuclear Information System (INIS)

Leahy, Timothy J.

2010-01-01

The Generation IV International Forum (GIF) Risk and Safety Working Group (RSWG) was created to develop an effective approach for the safety of Generation IV advanced nuclear energy systems. Early work of the RSWG focused on defining a safety philosophy founded on lessons learned from current and prior generations of nuclear technologies, and on identifying technology characteristics that may help achieve Generation IV safety goals. More recent RSWG work has focused on the definition of an integrated safety assessment methodology for evaluating the safety of Generation IV systems. The methodology, tentatively called ISAM, is an integrated 'toolkit' consisting of analytical techniques that are available and matched to appropriate stages of Generation IV system concept development. The integrated methodology is intended to yield safety-related insights that help actively drive the evolving design throughout the technology development cycle, potentially resulting in enhanced safety, reduced costs, and shortened development time.

Nonclassical state generation for linear quantum systems via nonlinear feedback control

International Nuclear Information System (INIS)

Ohki, Kentaro; Tsumura, Koji; Takeuchi, Reiji

2017-01-01

In this paper, we propose a measurement nonlinear feedback control scheme to generate Wigner-function negativity in an optical cavity having dynamics described as a linear quantum system. In general, linear optical quantum systems can be easily constructed with reliable devices; therefore, the idea of constructing the entire system with such an optical system and nonlinear feedback is reasonable for generating Wigner-function negativity. However, existing studies have insufficiently examined the realizability or actual implementation of feedback control, which essentially requires fast responses from the sensors and actuators. In order to solve this problem, we consider the realizable feedback control of the optical phase of a pumping beam supplied to a cavity by using electro-optical modulation, which can be utilized as a fast control actuator. Then, we introduce mathematical models of the feedback-controlled system and evaluate its effect on the generation of the Wigner-function negativity by using numerical simulation. Through various numerical simulations, we show that the proposed feedback control can effectively generate the negativity of the Wigner function. (paper)

Generation of multi-wing chaotic attractor in fractional order system

International Nuclear Information System (INIS)

Zhang Chaoxia; Yu Simin

2011-01-01

Highlights: → We investigate a novel approach for generating multi-wing chaotic attractors. → We introduce a fundamental fractional differential nominal linear system. → A proper nonlinear state feedback controller is designed. → The controlled system can generate fractional-order multi-wing chaotic attractors. - Abstract: In this paper, a novel approach is proposed for generating multi-wing chaotic attractors from the fractional linear differential system via nonlinear state feedback controller equipped with a duality-symmetric multi-segment quadratic function. The main idea is to design a proper nonlinear state feedback controller by using four construction criterions from a fundamental fractional differential nominal linear system, so that the controlled fractional differential system can generate multi-wing chaotic attractors. It is the first time in the literature to report the multi-wing chaotic attractors from an uncoupled fractional differential system. Furthermore, some basic dynamical analysis and numerical simulations are also given, confirming the effectiveness of the proposed method.

Prompt-gamma neutron activation analysis system design. Effects of D-T versus D-D neutron generator source selection

International Nuclear Information System (INIS)

Shypailo, R.J.; Ellis, K.J.

2008-01-01

Prompt-gamma neutron activation (PGNA) analysis is used for the non-invasive measurement of human body composition. Advancements in portable, compact neutron generator design have made those devices attractive as neutron sources. Two distinct generators are available: D-D with 2.5 MeV and D-T with 14.2 MeV neutrons. To compare the performance of these two units in our present PGNA system, we performed Monte Carlo simulations (MCNP-5; Los Alamos National Laboratory) evaluating the nitrogen reactions produced in tissue-equivalent phantoms and the effects of background interference on the gamma-detectors. Monte Carlo response curves showed increased gamma production per unit dose when using the D-D generator, suggesting that it is the more suitable choice for smaller sized subjects. The increased penetration by higher energy neutrons produced by the D-T generator supports its utility when examining larger, especially obese, subjects. A clinical PGNA analysis design incorporating both neutron generator options may be the best choice for a system required to measure a wide range of subject phenotypes. (author)

STARTER-GENERATOR SYSTEM FOR AUXILIARY POWER UNIT

Directory of Open Access Journals (Sweden)

A. V. Levin

2017-01-01

Full Text Available The article presents a starter-generator system for an auxiliary power unit of an aircraft. A feature of the presented system is the use of a synchronous generator with excitation from permanent magnets and a semiconductor converter. The main problem of the system is the generation of electric energy of an aircraft on the basis of a synchronous generator with excitation from permanent magnets is the absence of the possibility of regulating the voltage and frequency of electrical energy, in this connection, a semiconductor converter that ensures the conversion of generated electric energy with significant mass-dimensions characteristics.The article proposes an approach to designing a starter-generator system with a parallel connection of a synchronous generator with excitation from permanent magnets and a semiconductor converter. This approach makes it possible to significantly reduce the part of the electrical energy that needs to be converted, as a consequence, the semiconductor converter has significantly smaller mass-and-batch characteristics.In the article the modes of generation of electric energy and the starter mode of operation of the starter-generator system are considered in detail, the circuit realization of the semiconductor converter is shown. A scheme for replacing one phase of the system for generating electric energy and calculating electric parameters is presented.The possibility of creating a highly efficient starter-generator system based on a synchronous generator with excitation from permanent magnets and a semiconductor converter for an auxiliary power plant of aircrafts is shown. Structural and basic schemes for constructing a system for generating electrical energy are proposed. The approach to the choice of rational circuit solutions is substantiated, basic estimates of the electrical parameters of the system are obtained. The possibility of achieving a specific mass of a semiconductor converter for synchronous

A model of oil-generation in a waterlogged and closed system

Science.gov (United States)

Zhigao, He

This paper presents a new model on synthetic effects on oil-generation in a waterlogged and closed system. It is suggested based on information about oil in high pressure layers (including gas dissolved in oil), marsh gas and its fermentative solution, fermentation processes and mechanisms, gaseous hydrocarbons of carbonate rocks by acid treatment, oil-field water, recent and ancient sediments, and simulation experiments of artificial marsh gas and biological action. The model differs completely from the theory of oil-generation by thermal degradation of kerogen but stresses the synthetic effects of oil-generation in special waterlogged and closed geological systems, the importance of pressure in oil-forming processes, and direct oil generation by micro-organisms. Oil generated directly by micro-organisms is a particular biochemical reaction. Another feature of this model is that generation, migration and accumulation of petroleum are considered as a whole.

Induction generator-induction motor wind-powered pumping system

Energy Technology Data Exchange (ETDEWEB)

Miranda, M.S.; Lyra, R.O.C.; Silva, S.R. [CPDEE - UFMG, Belo Horizonte (Brazil)

1997-12-31

The energy storage matter plays an important role in wind-electric conversion systems for isolated applications. Having that in mind, two different approaches can be basically considered: either the immediate conversion of the generated electric energy, as in a water pumping system or electric energy storage for later use, as in a battery charging system. Due to some features such as no need of an external reactive power source and, sometimes, a gearbox, permanent-magnet synchronous generators have been broadly used in low rated power isolated systems. Despite that, system performance can be affected when the generator is feeding an inductive load (e.g., an induction motor) under variable-speed-variable-frequency operational conditions. Since there is no effective flux control, motor overload may occur at high wind speeds. Thus, good system performance can be obtained through additional control devices which may increase system cost. Although being rugged and cheap, induction machines always work as a reactive power drain; therefore, they demand an external reactive power source. Considering that, reactive static compensators appear as an attractive alternative to the cost x performance problem. In addition to that, different control strategies can be used so that system performance can be improved.

Multimegawatt disk generator system for space applications

International Nuclear Information System (INIS)

Solbes, H.; Iwata, H.

1988-01-01

The conceptual design of a 100 megawatt - 500 seconds disk MHD generator system suitable as a burst power source for a space based neutral particle beam (NPB) is presented. The system features two disk generators operated in the magnetic field produced by a single circular superconducting magnet. Gelled reactants are used as the energy source. The oxidizer gel includes the alkali seed. The high heat flux areas of the power train are water cooled. Heat is rejected to a hydrogen stream which is also used for cooling of the exit section. The hydrogen is also used to mitigate the effects of the exhaust products of combustion on the platform. The two disk channels are operated in parallel. A dc to dc converter consolidates the channel's output into a single 100 kilovolt dc output. Critical development issues relevant to the development of such power systems are identified and discussed. A R and D plan aimed at establishing the technical feasibility of the proposed system is also presented

Steam Generator Inspection Planning Expert System

International Nuclear Information System (INIS)

Rzasa, P.

1987-01-01

Applying Artificial Intelligence technology to steam generator non-destructive examination (NDE) can help identify high risk locations in steam generators and can aid in preparing technical specification compliant eddy current test (ECT) programs. A steam Generator Inspection Planning Expert System has been developed which can assist NDE or utility personnel in planning ECT programs. This system represents and processes its information using an object oriented declarative knowledge base, heuristic rules, and symbolic information processing, three artificial intelligence based techniques incorporated in the design. The output of the system is an automated generation of ECT programs. Used in an outage inspection, this system significantly reduced planning time

Steam generating system in LMFBR type reactors

International Nuclear Information System (INIS)

Kurosawa, Katsutoshi.

1984-01-01

Purpose: To suppress the thermal shock loads to the structures of reactor system and secondary coolant system, for instance, upon plant trip accompanying turbine trip in the steam generation system of LMFBR type reactors. Constitution: Additional feedwater heater is disposed to the pipeway at the inlet of a steam generator in a steam generation system equipped with a closed loop extended from a steam generator by way of a gas-liquid separator, a turbine and a condensator to the steam generator. The separated water at high temperature and high pressure from a gas-liquid separator is heat exchanged with coolants flowing through the closed loop of the steam generation system in non-contact manner and, thereafter, introduced to a water reservoir tank. This can avoid the water to be fed at low temperature as it is to the steam generator, whereby the thermal shock loads to the structures of the reactor system and the secondary coolant system can be suppressed. (Moriyama, K.)

Forecasting Wind and Solar Generation: Improving System Operations, Greening the Grid (Spanish Version)

Energy Technology Data Exchange (ETDEWEB)

Tian, Tian; Chernyakhovskiy, Ilya; Brancucci Martinez-Anido, Carlo

2016-04-01

This document is the Spanish version of 'Greening the Grid- Forecasting Wind and Solar Generation Improving System Operations'. It discusses improving system operations with forecasting with and solar generation. By integrating variable renewable energy (VRE) forecasts into system operations, power system operators can anticipate up- and down-ramps in VRE generation in order to cost-effectively balance load and generation in intra-day and day-ahead scheduling. This leads to reduced fuel costs, improved system reliability, and maximum use of renewable resources.

Corrosion products in power generating systems

International Nuclear Information System (INIS)

Lister, D.H.

1980-06-01

The important mechanisms of corrosion and corrosion product movement and fouling in the heat transport systems of thermal electric generating stations are reviewed. Oil- and coal-fired boilers are considered, along with nuclear power systems - both direct and indirect cycle. Thus, the fireside and waterside in conventional plants, and the primary coolant and steam-raising circuits in water-cooled reactors, are discussed. Corrosion products in organic- and liquid-metal-cooled reactors also are shown to cause problems if not controlled, while their beneficial effects on the cooling water side of condensers are described. (auth)

Development of fast neutron radiography system based on portable neutron generator

Energy Technology Data Exchange (ETDEWEB)

Yi, Chia Jia, E-mail: gei-i-kani@hotmail.com; Nilsuwankosit, Sunchai, E-mail: sunchai.n@chula.ac.th [Department of Nuclear Engineering, Faculty of Engineering, Chulalongkorn University, Phayathai Rd., Patumwan, Bangkok, THAILAND 10330 (Thailand)

2016-01-22

Due to the high installation cost, the safety concern and the immobility of the research reactors, the neutron radiography system based on portable neutron generator is proposed. Since the neutrons generated from a portable neutron generator are mostly the fast neutrons, the system is emphasized on using the fast neutrons for the purpose of conducting the radiography. In order to suppress the influence of X-ray produced by the neutron generator, a combination of a shielding material sandwiched between two identical imaging plates is used. A binary XOR operation is then applied for combining the information from the imaging plates. The raw images obtained confirm that the X-ray really has a large effect and that XOR operation can help enhance the effect of the neutrons.

Pulsed high-pressure (PHP) drain-down of steam generating system

International Nuclear Information System (INIS)

Petrusek, R.A.

1991-01-01

This patent describes an improved method of draining down contained reactor-coolant water from the inverted vertical U-tubes of at least one vertical-type steam generator in which the upper inverted U-shaped ends of the tubes are closed and the lower ends thereof are open, the steam generator having a channel head at its lower end including a vertical dividing wall defining a primary water inlet side and a primary water outlet side of the generator, the steam generator having chemical volume control system means and residual heat removal system means, and the steam generator being part of a nuclear-powered steam generating system wherein the reactor-coolant water is normally circulated from and back into the reactor via a loop comprising the steam generator and inlet and outlet conduits connected to the lower end of the steam generator, and the reactor being in communication with pressurizer means and comprising the steps of introducing a gas which is inert to the system and which is under pressure above atmospheric pressure into at least one of the downwardly facing open ends of each of the U-tubes from below the tubesheet in which the open ends of the U-tubes are mounted adjacent the lower end of the steam generator while permitting the water to flow out from the open ends of the U-tubes, the improvement in combination therewith for substantially increasing the effectiveness and efficiency of such water removal from the tubes. It includes determining the parameters effecting a first average volumetric rate of removal for a predetermined period of time, infra, of the reactor-coolant water from the inverted vertical U-tubes, the specific unit for the first average volumetric rate expressing properties identical with the properties expressed in a second average volumetric rate maintained in a later mentioned step

Digital chaotic sequence generator based on coupled chaotic systems

International Nuclear Information System (INIS)

Shu-Bo, Liu; Jing, Sun; Jin-Shuo, Liu; Zheng-Quan, Xu

2009-01-01

Chaotic systems perform well as a new rich source of cryptography and pseudo-random coding. Unfortunately their digital dynamical properties would degrade due to the finite computing precision. Proposed in this paper is a modified digital chaotic sequence generator based on chaotic logistic systems with a coupling structure where one chaotic subsystem generates perturbation signals to disturb the control parameter of the other one. The numerical simulations show that the length of chaotic orbits, the output distribution of chaotic system, and the security of chaotic sequences have been greatly improved. Moreover the chaotic sequence period can be extended at least by one order of magnitude longer than that of the uncoupled logistic system and the difficulty in decrypting increases 2 128 *2 128 times indicating that the dynamical degradation of digital chaos is effectively improved. A field programmable gate array (FPGA) implementation of an algorithm is given and the corresponding experiment shows that the output speed of the generated chaotic sequences can reach 571.4 Mbps indicating that the designed generator can be applied to the real-time video image encryption. (general)

Towards an Explanation Generation System for Robots: Analysis and Recommendations

Directory of Open Access Journals (Sweden)

Ben Meadows

2016-10-01

Full Text Available A fundamental challenge in robotics is to reason with incomplete domain knowledge to explain unexpected observations and partial descriptions extracted from sensor observations. Existing explanation generation systems draw on ideas that can be mapped to a multidimensional space of system characteristics, defined by distinctions, such as how they represent knowledge and if and how they reason with heuristic guidance. Instances in this multidimensional space corresponding to existing systems do not support all of the desired explanation generation capabilities for robots. We seek to address this limitation by thoroughly understanding the range of explanation generation capabilities and the interplay between the distinctions that characterize them. Towards this objective, this paper first specifies three fundamental distinctions that can be used to characterize many existing explanation generation systems. We explore and understand the effects of these distinctions by comparing the capabilities of two systems that differ substantially along these axes, using execution scenarios involving a robot waiter assisting in seating people and delivering orders in a restaurant. The second part of the paper uses this study to argue that the desired explanation generation capabilities corresponding to these three distinctions can mostly be achieved by exploiting the complementary strengths of the two systems that were explored. This is followed by a discussion of the capabilities related to other major distinctions to provide detailed recommendations for developing an explanation generation system for robots.

Effectiveness of micronic aerosol generators and their aerosol characteristics

International Nuclear Information System (INIS)

Chinet, T.; Collignon, M.-A.; Dusser, D.; Barritault, L.; Huchon, G.J.

1986-01-01

We assessed the effectiveness of various aerosol-generating systems. Taplin's settling method and Venticis generators has a lower efficiency (37.3 +- 3.8% and 51.8 +- 9.6%, respectively) than the Syntevent (88.8 +- 6.9%, p<0.001), Cadema (89.8 +- 9.9%, p<0.001) and Mefar (85.3 +- 19.4%, p<0.001) generators. The Mass Median Aerodynamic Diameter of the particles produced by the Mefar nebulizer (2.05 +- 0.27 μm) was larger than that of any other generators (p<0.001). The Syntevent (0.54 +- 0.09 μm) generator produced smaller particles than the Mefar, Taplin (0.89 +- 0.10 μm, p<0.01) and Venticis (0.79 +- 0.06 μm, p<0.02) generators. Particles produced by the Cadema system (0.69 +- 0.06 μm) were smaller than those generated by the Taplin system(p<0.05). We conclude: 1) that the Syntevent, Mefar and Cadema aerosol generators are more efficient than the others, and 2) that all the generators tested except the Mefar may be used for studies that depend on the peripheral deposition of small particles within the lungs. (author)

Solar energy thermally powered electrical generating system

Science.gov (United States)

Owens, William R. (Inventor)

1989-01-01

A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

Hydrogen storage and generation system

Science.gov (United States)

Dentinger, Paul M.; Crowell, Jeffrey A. W.

2010-08-24

A system for storing and generating hydrogen generally and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses the beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

Adequacy assessment of composite generation and transmission systems incorporating wind energy conversion systems

Science.gov (United States)

Gao, Yi

The development and utilization of wind energy for satisfying electrical demand has received considerable attention in recent years due to its tremendous environmental, social and economic benefits, together with public support and government incentives. Electric power generation from wind energy behaves quite differently from that of conventional sources. The fundamentally different operating characteristics of wind energy facilities therefore affect power system reliability in a different manner than those of conventional systems. The reliability impact of such a highly variable energy source is an important aspect that must be assessed when the wind power penetration is significant. The focus of the research described in this thesis is on the utilization of state sampling Monte Carlo simulation in wind integrated bulk electric system reliability analysis and the application of these concepts in system planning and decision making. Load forecast uncertainty is an important factor in long range planning and system development. This thesis describes two approximate approaches developed to reduce the number of steps in a load duration curve which includes load forecast uncertainty, and to provide reasonably accurate generating and bulk system reliability index predictions. The developed approaches are illustrated by application to two composite test systems. A method of generating correlated random numbers with uniform distributions and a specified correlation coefficient in the state sampling method is proposed and used to conduct adequacy assessment in generating systems and in bulk electric systems containing correlated wind farms in this thesis. The studies described show that it is possible to use the state sampling Monte Carlo simulation technique to quantitatively assess the reliability implications associated with adding wind power to a composite generation and transmission system including the effects of multiple correlated wind sites. This is an important

Multimegawatt disk generator system for space applications

International Nuclear Information System (INIS)

Solbes, A.; Iwata, H.

1988-01-01

The conceptual design of a 100 megawatt - 500 seconds disk MHD generator system suitable as a burst power source for a space based neutral particle beam (NPB) is presented. The system features two disk generators operated in the magnetic field produced by a single circular superconducting magnet. Gelled reactants are used as the energy source. The oxidizer gel includes the alkali seed. The high heat flux areas of the power train are water cooled. Heat is rejected to a hydrogen stream which is also used for cooling of the exit section. The hydrogen is also used to mitigate the effects of the exhaust products of combustion on the platform. The two disk channels are operated in parallel. A dc to dc converter consolidates the channel's output into a single 100 kilovolt dc output

Generation IV nuclear energy systems: road map and concepts. 2. Generation II Measurement Systems for Generation IV Nuclear Power Plants

International Nuclear Information System (INIS)

Miller, Don W.

2001-01-01

Instrumentation and Control (I and C) systems in current operating plants have not changed appreciably since their original design in the 1950's. These systems depend on a variety of traditional process and radiation sensors for the measurement of safety and control variables such as temperature, pressure, and neutron flux. To improve their performance and to make them more robust, many plant control systems have been upgraded from analog to digital; most of them continue to utilize traditional single-input single-output architecture. Transmission of data, for the most part, continues to employ large coaxial cables. These cables are not the small cables used in a laboratory (i.e., RG-58 or RG-59). Because of concern about electromagnetic and radio frequency interference and other environmental effects, bulky triax cables, which are cables with two outer shields separated by an insulator, are used. In a nuclear plant there are literally miles of cables and hundreds of specialized penetrations for cables going through containment or pressure vessel walls. The I and C systems in the advanced light water reactor (ALWR) designs, i.e., Generation III reactors, do employ more advanced technology than current plants; however, they do not incorporate new technology on a broad scale. This in part is a consequence of the ALWR design philosophy that discouraged use of advanced technology if current technology was adequate. As a consequence, the I and C systems in the ALWRs continue to make use of current technology. There are two exceptions, however, which include the broad use of software-based digital systems and fiber optics for signal isolation and data transmission in nonradioactive areas. The ALWR design philosophy was a justifiably low-risk approach when considering the overall objective of 'capturing' lessons learned from current operating plants to design a plant that would exhibit performance superior to current plants and would be relatively easy to license without

The comparative study on the environmental impact for various energy generating systems

International Nuclear Information System (INIS)

Jung, J. T.; Ha, J. J.; Jung, H. S.

2002-01-01

The concern about environmental problem due to electricity generation is increasing. And the current debate about the environmental and socioeconomic effects of energy use is now turning towards the internalization of externalities imposed on society and the environment that are not accounted by the producers and consumers of energy. The result of internalization of externalities are to be used in the decision making of selecting available options. Therefore, the environmental impact analysis for various energy generating systems were made by using Life Cycle Assessment(LCA). According to the results, the environmental burden due to nuclear power generating systems is low comparing with other energy generating systems due to low usage of resources. The results will be used in the comparative study on the environmental impacts for various energy generating systems

Neutron generator control system

International Nuclear Information System (INIS)

Peelman, H.E.; Bridges, J.R.

1981-01-01

A method is described of controlling the neutron output of a neutron generator tube used in neutron well logging. The system operates by monitoring the target beam current and comparing a function of this current with a reference voltage level to develop a control signal used in a series regulator to control the replenisher current of the neutron generator tube. (U.K.)

Design of MHD generator systems

International Nuclear Information System (INIS)

Buende, R.; Raeder, J.

1975-01-01

By assessment of the influence of the combustion efficiency on the electric output of the MHD generator, it can be shown that the construction and efficiency of the generator strongly depend on these parameters. The solutions of this system of equations are discussed. Following a derivation of criteria and boundary conditions of the design and a determination of the specific construction costs of individual system components, it is shown how the single design parameters influence the operational characteristics of such a system, especially the output, efficiency and energy production costs. (GG/LH) [de

Systems Prototyping with Fourth Generation Tools.

Science.gov (United States)

Sholtys, Phyllis

1983-01-01

The development of information systems using an engineering approach that uses both traditional programing techniques and fourth generation software tools is described. Fourth generation applications tools are used to quickly develop a prototype system that is revised as the user clarifies requirements. (MLW)

Enhanced Control for a Direct-driven Permanent Synchronous Generator Wind-power Generation System with Flywheel Energy Storage Unit Under Unbalanced Grid Fault

DEFF Research Database (Denmark)

Yao, Jun; Zhou, Te; Hu, Weihao

2015-01-01

This article presents an enhanced control strategy for a direct-driven permanent synchronous generator based wind-power generation system with a flywheel energy storage unit. The behaviors of the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit under......, the DC-link voltage oscillations can be effectively suppressed during the unbalanced grid fault by controlling the flywheel energy storage unit. Furthermore, a proportional–integral-resonant controller is designed for the flywheel motor to eliminate the oscillations in the DC-link voltage. Finally......, the proposed coordinated control strategy for the direct-driven permanent magnet synchronous generator system with a flywheel energy storage unit has been validated by the simulation results of a 1-MW direct-driven permanent magnet synchronous generator wind power generation system with a flywheel energy...

Application of photovoltaic generating system to electric power in large ship; Taiyoko hatsuden system no ogata senpaku eno oyo ni kansuru kento

Energy Technology Data Exchange (ETDEWEB)

Katagi, T; Ogawa, S; Nishikawa, E; Hashimoto, T [Kobe University of Mercantile Marine, Kobe (Japan); Ishida, K

1996-10-27

This paper describes the design of electric power system in a ship with photovoltaic power generating system, to examine applicability of the photovoltaic power generating system to the inboard power source. It also discusses effectiveness of the system for sea environment. At first, the actual route of a car carrier, meteorological data, and quantity of power consumption were picked up from the deck logbook and engine logbook. Then, the installation area of photovoltaic arrays, the quantity of photovoltaic power generation derived from the quantity of solar radiation, and the capacities of batteries and inverters were calculated, to design the electric power system in the ship with photovoltaic power generation system. Moreover, the NOx and SOx emissions were compared between the present power system and the usual power system using diesel power generator, to discuss the effectiveness of the present system for sea environment. Consequently, it was found that the emission of NOx was reduced by about 33% and the emission of SOx was reduced by about 28% compared to the usual power system. The effectiveness for sea environment was confirmed. 9 refs., 5 figs., 4 tabs.

Design of fault tolerant control system for steam generator using

Energy Technology Data Exchange (ETDEWEB)

Kim, Myung Ki; Seo, Mi Ro [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

1998-12-31

A controller and sensor fault tolerant system for a steam generator is designed with fuzzy logic. A structure of the proposed fault tolerant redundant system is composed of a supervisor and two fuzzy weighting modulators. A supervisor alternatively checks a controller and a sensor induced performances to identify which part, a controller or a sensor, is faulty. In order to analyze controller induced performance both an error and a change in error of the system output are chosen as fuzzy variables. The fuzzy logic for a sensor induced performance uses two variables : a deviation between two sensor outputs and its frequency. Fuzzy weighting modulator generates an output signal compensated for faulty input signal. Simulations show that the proposed fault tolerant control scheme for a steam generator regulates well water level by suppressing fault effect of either controllers or sensors. Therefore through duplicating sensors and controllers with the proposed fault tolerant scheme, both a reliability of a steam generator control and sensor system and that of a power plant increase even more. 2 refs., 9 figs., 1 tab. (Author)

Fuel oil systems for standby diesel-generators

International Nuclear Information System (INIS)

Anon.

1976-01-01

This Standard provides the design requirements for fuel oil system for diesel-generators that provide standby power for a nuclear power generating station. The system includes all essential equipment from and including fuel oil storage tanks up to the terminal connection on the diesel-engine. It does not include that portion of the fuel oil system supplied by the diesel-generator manufacturer which is in accordance with Trial-Use Criteria for Diesel-Generator Units Applied as Standby Power Supplies for Nuclear Power Generating Stations, IEEE-387-1972. This definition of scope is intended to exclude only those factory-assembled, engine-mounted appurtances supplied with a diesel-generator unit. Integral tanks are, however, within the scope of this Standard. It also excludes motors, motor control centers, switchgear, cables, and other electrical equipment which is used in operation of the fuel oil system, except to define interface requirements

Methodology toward second generation expert systems

International Nuclear Information System (INIS)

Dormoy, J.L.

1989-01-01

So-called First Generation Expert Systems were aimed at capturing the expert's know-how. Though providing remarkable achievements, this first wave did not give the expected outcome. A new generation is getting out from the laboratories. Instead of remaining at a shallow level of knowledge - that is the unmotivated reasoning processes expressed by an expert when he is forced to tell them - one attempts to re-build this level of knowledge from the first principles which constitute the basis of an expert's knowledge. These systems are called deep knowledge-based, or second generation expert systems. Discussion in the three first parts rests on two examples: A first generation and a half system for process control in nuclear powers plants, than the system EXTRA for alarm processing in nuclear plants, wherein fonctional knowledge is explicitely represented. We show how deep knowledge can be implemented, and the advantages that can be expected from this methodology. Qualitative Physics is discussed in the next part. Future research developments as well as potential payoffs are mentioned [fr

A novel HTS SMES application in combination with a permanent magnet synchronous generator type wind power generation system

Science.gov (United States)

Kim, G. H.; Kim, A. R.; Kim, S.; Park, M.; Yu, I. K.; Seong, K. C.; Won, Y. J.

2011-11-01

Superconducting magnetic energy storage (SMES) system is a DC current driven device and can be utilized to improve power quality particularly in connection with renewable energy sources due to higher efficiency and faster response than other devices. This paper suggests a novel connection topology of SMES which can smoothen the output power flow of the wind power generation system (WPGS). The structure of the proposed system is cost-effective because it reduces a power converter in comparison with a conventional application of SMES. One more advantage of SMES in the proposed system is to improve the capability of low voltage ride through (LVRT) for the permanent magnet synchronous generator (PMSG) type WPGS. The proposed system including a SMES has been modeled and analyzed by a PSCAD/EMTDC. The simulation results show the effectiveness of the novel SMES application strategy to not only mitigate the output power of the PMSG but also improve the capability of LVRT for PMSG type WPGS.

Diagnostic system of steam generator, especially molten metal heated steam generator

International Nuclear Information System (INIS)

Matal, O.; Martoch, J.

1986-01-01

A diagnostic system is described and graphically represented consisting of a leak detector, a medium analyzer and sensors placed on the piping connected to the indication sections of both tube plates. The advantage of the designed system consists in the possibility of detecting tube failure immediately on leak formation, especially in generators with duplex tubes. This shortens the period of steam generator shutdown for repair and reduces power losses. The design also allows to make periodical leak tests during planned steam generator shutdowns. (A.K.)

Using natural gas generation to improve power system efficiency in China

International Nuclear Information System (INIS)

Hu, Junfeng; Kwok, Gabe; Xuan, Wang; Williams, James H.; Kahrl, Fredrich

2013-01-01

China's electricity sector faces the challenge of managing cost increases, improving reliability, and reducing its environmental footprint even as operating conditions become more complex due to increasing renewable penetration, growing peak demand, and falling system load factors. Addressing these challenges will require changes in how power generation is planned, priced, and dispatched in China. This is especially true for natural gas generation, which is likely to play an important role in power systems worldwide as a flexible generation resource. Although natural gas is commonly perceived to be economically uncompetitive with coal in China, these perceptions are based on analysis that fails to account for the different roles that natural gas generation plays in power systems—baseload, load following, and peaking generation. Our analysis shows that natural gas generation is already cost-effective for meeting peak demand in China, resulting in improved capacity factors and heat rates for coal-fired generators and lower system costs. We find that the largest barrier to using natural gas for peaking generation in China is generation pricing, which could be addressed through modest reforms to support low capacity factor generation. - Highlights: • Using gas generation as a “capacity resource” in China could have multiple benefits. • Benefits include lower total costs, improved efficiency for coal generators. • Price reforms needed to support low capacity factor generation in China

Implementation of optimum solar electricity generating system

International Nuclear Information System (INIS)

Singh, Balbir Singh Mahinder; Karim, Samsul Ariffin A.; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep

2014-01-01

Under the 10 th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels

Implementation of optimum solar electricity generating system

Science.gov (United States)

Singh, Balbir Singh Mahinder; Sivapalan, Subarna; Najib, Nurul Syafiqah Mohd; Menon, Pradeep; Karim, Samsul Ariffin A.

2014-10-01

Under the 10th Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

Implementation of optimum solar electricity generating system

Energy Technology Data Exchange (ETDEWEB)

Singh, Balbir Singh Mahinder, E-mail: balbir@petronas.com.my; Karim, Samsul Ariffin A., E-mail: samsul-ariffin@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Sivapalan, Subarna, E-mail: subarna-sivapalan@petronas.com.my [Department of Management and Humanities, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia); Najib, Nurul Syafiqah Mohd; Menon, Pradeep [Department of Electrical and Electronics Engineering, Universiti Teknologi PETRONAS, 31750 Bandar Seri Iskandar, Perak (Malaysia)

2014-10-24

Under the 10{sup th} Malaysian Plan, the government is expecting the renewable energy to contribute approximately 5.5% to the total electricity generation by the year 2015, which amounts to 98MW. One of the initiatives to ensure that the target is achievable was to establish the Sustainable Energy Development Authority of Malaysia. SEDA is given the authority to administer and manage the implementation of the feed-in tariff (FiT) mechanism which is mandated under the Renewable Energy Act 2011. The move to establish SEDA is commendable and the FiT seems to be attractive but there is a need to create awareness on the implementation of the solar electricity generating system (SEGS). In Malaysia, harnessing technologies related to solar energy resources have great potential for implementation. However, the main issue that plagues the implementation of SEGS is the intermittent nature of this source of energy. The availability of sunlight is during the day time, and there is a need for electrical energy storage system, so that there is electricity available during the night time as well. The meteorological condition such as clouds, haze and pollution affects the SEGS as well. The PV based SEGS is seems to be promising electricity generating system that can contribute towards achieving the 5.5% target and will be able to minimize the negative effects of utilizing fossil fuels for electricity generation on the environment. Malaysia is committed to Kyoto Protocol, which emphasizes on fighting global warming by achieving stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. In this paper, the technical aspects of the implementation of optimum SEGS is discussed, especially pertaining to the positioning of the PV panels.

Automotive dual-mode hydrogen generation system

Science.gov (United States)

Kelly, D. A.

The automotive dual mode hydrogen generation system is advocated as a supplementary hydrogen fuel means along with the current metallic hydride hydrogen storage method for vehicles. This system consists of utilizing conventional electrolysis cells with the low voltage dc electrical power supplied by two electrical generating sources within the vehicle. Since the automobile engine exhaust manifold(s) are presently an untapped useful source of thermal energy, they can be employed as the heat source for a simple heat engine/generator arrangement. The second, and minor electrical generating means consists of multiple, miniature air disk generators which are mounted directly under the vehicle's hood and at other convenient locations within the engine compartment. The air disk generators are revolved at a speed which is proportionate to the vehicles forward speed and do not impose a drag on the vehicles motion.

Neural net based determination of generator-shedding requirements in electric power systems

Energy Technology Data Exchange (ETDEWEB)

Djukanovic, M [Electrical Engineering Inst. ' Nikola Tesla' , Belgrade (Yugoslavia); Sobajic, D J; Pao, Y -H [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Electrical Engineering and Applied Physics Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Computer Engineering and Science AI WARE Inc., Cleveland, OH (United States)

1992-09-01

This paper presents an application of artificial neural networks (ANN) in support of a decision-making process by power system operators directed towards the fast stabilisation of multi-machine systems. The proposed approach considers generator shedding as the most effective discrete supplementary control for improving the dynamic performance of faulted power systems and preventing instabilities. The sensitivity of the transient energy function (TEF) with respect to changes in the amount of dropped generation is used during the training phase of ANNs to assess the critical amount of generator shedding required to prevent the loss of synchronism. The learning capabilities of neural nets are used to establish complex mappings between fault information and the amount of generation to be shed, suggesting it as the control signal to the power system operator. (author)

Conceptual design and system analysis of a poly-generation system for power and olefin production from natural gas

International Nuclear Information System (INIS)

Qian Yu; Liu Jingyao; Huang Zhixian; Kraslawski, Andrzej; Cui Jian; Huang Yinlun

2009-01-01

In this paper, a novel poly-generation system for olefin and power production from natural gas is proposed, which integrates hydrocarbon production and the combined cycle power generation. Economic and technological evaluation based on the internal rate of return (IRR) and exergy efficiency is performed. The energy integration results in the proposed poly-generation system for simultaneous production of chemical products (ethylene and propylene) and electricity being more thermodynamically efficient and economically viable than single purpose power generation and chemical products production plants. IRR and exergy efficiency of the proposed poly-generation system are higher than that of natural gas methanol to olefin (NGMTO) system, 18.9% and 49.9%, respectively. The biggest exergy destruction segments, their causes, and possible measures for improvement are investigated simulation and thermodynamic analysis. To analyze the effect of unreacted syngas recycle on the exergy efficiency and economic gains from the proposed poly-generation system, its thermoeconomic optimization model is built by combining economic with thermodynamic analysis. Optimization analysis shows that when 78% of the unreacted syngas is recycled back to the reactor in the methanol synthesization process, the thermoeconomic performance of the poly-generation system is at its optimum.

Culinary and pressure irrigation water system hydroelectric generation

Energy Technology Data Exchange (ETDEWEB)

Christiansen, Cory [Water Works Engineers, Pleasant Grove City, UT (United States)

2016-01-29

Pleasant Grove City owns and operates a drinking water system that included pressure reducing stations (PRVs) in various locations and flow conditions. Several of these station are suitable for power generation. The City evaluated their system to identify opportunities for power generation that can be implemented based on the analysis of costs and prediction of power generation and associated revenue. The evaluation led to the selection of the Battle Creek site for development of a hydro-electric power generating system. The Battle Creek site includes a pipeline that carries spring water to storage tanks. The system utilizes a PRV to reduce pressure before the water is introduced into the tanks. The evaluation recommended that the PRV at this location be replaced with a turbine for the generation of electricity. The system will be connected to the utility power grid for use in the community. A pelton turbine was selected for the site, and a turbine building and piping system were constructed to complete a fully functional power generation system. It is anticipated that the system will generate approximately 440,000 kW-hr per year resulting in $40,000 of annual revenue.

Multifunctional pulse generator for high-intensity focused ultrasound system

Science.gov (United States)

Tamano, Satoshi; Yoshizawa, Shin; Umemura, Shin-Ichiro

2017-07-01

High-intensity focused ultrasound (HIFU) can achieve high spatial resolution for the treatment of diseases. A major technical challenge in implementing a HIFU therapeutic system is to generate high-voltage high-current signals for effectively exciting a multichannel HIFU transducer at high efficiencies. In this paper, we present the development of a multifunctional multichannel generator/driver. The generator can produce a long burst as well as an extremely high-voltage short pulse of pseudosinusoidal waves (trigger HIFU) and second-harmonic superimposed waves for HIFU transmission. The transmission timing, waveform, and frequency can be controlled using a field-programmable gate array (FPGA) via a universal serial bus (USB) microcontroller. The hardware is implemented in a compact printed circuit board. The test results of trigger HIFU reveal that the power consumption and the temperature rise of metal-oxide semiconductor field-effect transistors were reduced by 19.9% and 38.2 °C, respectively, from the previous design. The highly flexible performance of the novel generator/driver is demonstrated in the generation of second-harmonic superimposed waves, which is useful for cavitation-enhanced HIFU treatment, although the previous design exhibited difficulty in generating it.

Development of a steam generator lancing system

International Nuclear Information System (INIS)

Jeong, Woo-Tae; Kim, Seok-Tae; Hong, Sung-Yull

2006-01-01

It is recommended to clean steam generators of nuclear power plants during plant outages. Under normal operations, sludge is created and constantly accumulates in the steam generators. The constituents of this sludge are different depending on each power plant characteristics. The sludge of the Kori Unit 1 steam generator, for example, was found to be composed of 93% ferrous oxide, 3% carbon and 1% of silica oxide and nickel oxide each. The research to develop a lancing system that would remove sludge deposits from the tubesheet of a steam generator was started in 1998 by the Korea Electric Power Research Institute (KEPRI) of the Korea Electric Power Corporation (KEPCO). The first commercial domestic lancing system in Korea, and KALANS-I Lancing System, was completed in 2000 for Kori Unit 1 for cleaning the tubesheet of its Westinghouse Delta-60 steam generator. Thereafter, the success of the development and site implementation of the KALANS-I lancing system for YGN Units 1 and 2 and Ulchin Units 3 and 4 was also realized in 2004 for sludge removal at those sites. The upper bundle cleaning system for Westinghouse model F steam generators is now under development

Reliability Evaluation of Distribution System Considering Sequential Characteristics of Distributed Generation

Directory of Open Access Journals (Sweden)

Sheng Wanxing

2016-01-01

Full Text Available In allusion to the randomness of output power of distributed generation (DG, a reliability evaluation model based on sequential Monte Carlo simulation (SMCS for distribution system with DG is proposed. Operating states of the distribution system can be sampled by SMCS in chronological order thus the corresponding output power of DG can be generated. The proposed method has been tested on feeder F4 of IEEE-RBTS Bus 6. The results show that reliability evaluation of distribution system considering the uncertainty of output power of DG can be effectively implemented by SMCS.

Study on a constant-tip-speed-ratio operation of wind power generation system. Effect of load control system on dynamic behavior; Furyoku hatsuden system no hensoku seigyo unten ni kansuru kenkyu. Fuka seigyokei ga system no rikigakuteki kyodo ni oyobosu eikyo

Energy Technology Data Exchange (ETDEWEB)

Wakui, T.; Yamaguchi, K. [Waseda University, Tokyo (Japan); Tanzawa, Y. [Nippon Institute of Technology, Saitama (Japan); Hashizume, T.; Ota, E. [Waseda University, Tokyo (Japan). School of Science and Engineering

1998-06-01

The effect that the set data of the load control system in a wind power generation system exerts on the dynamic behavior of a system was investigated. The wind power generation system consists of a hybrid wind turbine with combined Darrieus and Savonius rotors, load with a generator and battery in the center, and a controller. A constant-tip-speed ratio operation that holds the circumferential speed ratio in which the power coefficient is maximized irrespective of the change in wind velocity was used to extract and convert the wind energy more effectively. In a high-wind velocity area, the system is operated at a fixed speed, and the increase in rotation is suppressed to protect the wing strength. In a large system, the response characteristics are only slightly improved by the limited load operation range and influenced rotor inertial. Power cannot be fully extracted even if the control system is changed in setting, and the applicability to the wind situation remains low. During the actual operation, the adjustment value of the control system should be set so that the output operation is satisfactorily possible in the specified load operation range, that is, the change in the instantaneous value of an effective power coefficient indicates almost flat gain characteristics in frequency characteristics. 14 refs., 10 figs., 2 tabs.

Performance characterization of a power generation unit–organic Rankine cycle system based on the efficiencies of the system components

International Nuclear Information System (INIS)

Knizley, Alta; Mago, Pedro J.; Tobermann, James; Warren, Harrison R.

2015-01-01

Highlights: • Use of waste heat from a power generation unit to generate electricity is explored. • An organic Rankine cycle is used to recover the waste heat. • The system may lower cost, primary energy consumption, and carbon dioxide emission. • A parameter was established to show when the proposed system would provide savings. • The proposed system was evaluated in different locations in the US. - Abstract: This paper analyzes the potential of using the waste heat from a power generation unit to generate additional electricity using an organic Rankine cycle to reduce operational cost, primary energy consumption, and carbon dioxide emissions in different locations in the U.S. The power generation unit–organic Rankine cycle system is compared with a conventional system in terms of operational cost, primary energy consumption, and carbon dioxide emissions reduction. A parameter (R_m_i_n), which is based on system efficiencies, is established to determine when the proposed power generation unit–organic Rankine cycle system would potentially provide savings versus the conventional system in which electricity is purchased from the utility grid. The effect on the R_m_i_n parameter with variation of each system efficiency is also analyzed in this paper. Results indicated that savings in one parameter, such as primary energy consumption, did not imply savings in the other two parameters. Savings in the three parameters (operational cost, primary energy consumption, and carbon dioxide emissions) varied widely based on location due to prices of natural gas and electricity, source-to-site conversion factors, and carbon dioxide emissions conversion factors for electricity and natural gas. Variations in each system efficiency affected R_m_i_n, but varying the power generation unit efficiency had the most dramatic effect in the overall savings potential from the proposed system.

Inertial effects on the stress generation of active fluids

Science.gov (United States)

Takatori, S. C.; Brady, J. F.

2017-09-01

Suspensions of self-propelled bodies generate a unique mechanical stress owing to their motility that impacts their large-scale collective behavior. For microswimmers suspended in a fluid with negligible particle inertia, we have shown that the virial swim stress is a useful quantity to understand the rheology and nonequilibrium behaviors of active soft matter systems. For larger self-propelled organisms such as fish, it is unclear how particle inertia impacts their stress generation and collective movement. Here we analyze the effects of finite particle inertia on the mechanical pressure (or stress) generated by a suspension of self-propelled bodies. We find that swimmers of all scales generate a unique swim stress and Reynolds stress that impact their collective motion. We discover that particle inertia plays a similar role as confinement in overdamped active Brownian systems, where the reduced run length of the swimmers decreases the swim stress and affects the phase behavior. Although the swim and Reynolds stresses vary individually with the magnitude of particle inertia, the sum of the two contributions is independent of particle inertia. This points to an important concept when computing stresses in computer simulations of nonequilibrium systems: The Reynolds and the virial stresses must both be calculated to obtain the overall stress generated by a system.

Integration of Renewable Generation in Power System Defence Plans

DEFF Research Database (Denmark)

Das, Kaushik

Increasing levels of penetration of wind power and other renewable generations in European power systems pose challenges to power system security. The power system operators are continuously challenged especially when generations from renewables are high thereby reducing online capacity of conven......Increasing levels of penetration of wind power and other renewable generations in European power systems pose challenges to power system security. The power system operators are continuously challenged especially when generations from renewables are high thereby reducing online capacity......, one of them being the North East area with high share of wind power generation.The aim of this study is to investigate how renewable generations like wind power can contribute to the power system defence plans. This PhD project “Integration of Renewable Generation in Power System Defence Plans...

Gas generation and migration analysis for TRU waste disposal system

International Nuclear Information System (INIS)

Ando, Kenichi; Noda, Masaru; Yamamoto, Mikihiko; Mihara, Morihiro

2005-09-01

In TRU waste disposal system, significant quantities of gases may be generated due to metal corrosion, radiolysis effect and microorganism activities. It is therefore recommended that the potential impact of gas generation and migration on TRU waste repository should be evaluated. In this study, gas generation rates were calculated in the repository and gas migration analysis in the disposal system were carried out using two phase flow model with results of gas generation rates. First, the time dependencies of gas generation rate in each TRU waste repositories were evaluated based on amounts of metal, organic matter and radioactivity. Next, the accumulation pressure of gases and expelled pore water volume nuclides in the repository were calculated by TOUGH2 code. After that, the results showed that the increase of gas pressure was the range of 1.3 to 1.4 MPa. In the repository with and without buffer, the rate of expelled pore water was 0.006 - 0.009 m 3 /y and 0.018 - 0.24m 3 /y, respectively. In addition, the radioactive gas migration through the repository and geosphere are evaluated. And re-saturation analysis is also performed to evaluate the initial condition of the system. (author)

Effects of debris generated by chemical reactions on head loss through emergency-core cooling-system strainers

International Nuclear Information System (INIS)

Howe, K.; Ghosh, A.; Maji, A.K.; Letellier, B.C.; Johns, R.; Chang, T.Y.

2004-01-01

The effect of debris generated during a loss of coolant accident (LOCA) on the emergency core cooling system (ECCS) strainers has been studied via numerous avenues over the last several years. The research described in this manuscript examines the generation and effect of secondary materials -- not debris generated in the LOCA itself, but materials created by chemical reactions between exposed surfaces/debris and cooling system water. The secondary materials studied in the research were corrosion products from exposed metallic surfaces and paint chips that may precipitate out of solution, with a focus on the corrosion products of aluminium, iron, and zinc. The processes of corrosion and leaching of metals with subsequent precipitation is important because: (1) the surface area of exposed metal inside containment represents a large potential source term, even for slow chemical reactions; the chemical composition of the cooling system water (boric acid, lithium, etc.) may affect corrosion or precipitation in ways that have not been studied thoroughly in the past; and (3) an eyewitness report of the presence of gelatinous material in the Three Mile Island containment pool after the 1979 accident suggests the formation of a secondary material that has not been examined under the generic safety issue (GSI)-191 research program. This research was limited in scope and consisted only of small-scale tests. Several key questions were investigated: (1) do credible corrosion mechanisms exist for leaching metal ions from bulk solid surfaces or from zinc-based paint chips, and if so, what are the typical rate constants? (2) can corrosion products accumulate in the containment pool water to the extent that they might precipitate as new chemical species at pH and temperatures levels that are relevant to the LOCA accident sequence? and (3) how do chemical precipitants affect the head loss across an existing fibrous debris bed? A full report of the research is available. (authors)

An Effective Fault Feature Extraction Method for Gas Turbine Generator System Diagnosis

Directory of Open Access Journals (Sweden)

Jian-Hua Zhong

2016-01-01

Full Text Available Fault diagnosis is very important to maintain the operation of a gas turbine generator system (GTGS in power plants, where any abnormal situations will interrupt the electricity supply. The fault diagnosis of the GTGS faces the main challenge that the acquired data, vibration or sound signals, contain a great deal of redundant information which extends the fault identification time and degrades the diagnostic accuracy. To improve the diagnostic performance in the GTGS, an effective fault feature extraction framework is proposed to solve the problem of the signal disorder and redundant information in the acquired signal. The proposed framework combines feature extraction with a general machine learning method, support vector machine (SVM, to implement an intelligent fault diagnosis. The feature extraction method adopts wavelet packet transform and time-domain statistical features to extract the features of faults from the vibration signal. To further reduce the redundant information in extracted features, kernel principal component analysis is applied in this study. Experimental results indicate that the proposed feature extracted technique is an effective method to extract the useful features of faults, resulting in improvement of the performance of fault diagnosis for the GTGS.

MOLIERE: Automatic Biomedical Hypothesis Generation System.

Science.gov (United States)

Sybrandt, Justin; Shtutman, Michael; Safro, Ilya

2017-08-01

Hypothesis generation is becoming a crucial time-saving technique which allows biomedical researchers to quickly discover implicit connections between important concepts. Typically, these systems operate on domain-specific fractions of public medical data. MOLIERE, in contrast, utilizes information from over 24.5 million documents. At the heart of our approach lies a multi-modal and multi-relational network of biomedical objects extracted from several heterogeneous datasets from the National Center for Biotechnology Information (NCBI). These objects include but are not limited to scientific papers, keywords, genes, proteins, diseases, and diagnoses. We model hypotheses using Latent Dirichlet Allocation applied on abstracts found near shortest paths discovered within this network, and demonstrate the effectiveness of MOLIERE by performing hypothesis generation on historical data. Our network, implementation, and resulting data are all publicly available for the broad scientific community.

Hazard of electrostatic generation in a pneumatic conveying system: electrostatic effects on the accuracy of electrical capacitance tomography measurements and generation of spark

International Nuclear Information System (INIS)

Zhang, Yan; Wang, Chi-Hwa; Liang, Yung Chii

2008-01-01

The study of the hazard of electrostatic generation in pneumatic conveying systems was attempted by examining the sensitivity of electrical capacitance tomography (ECT) and the phenomena of spark generation due to strong electrostatics. The influence on ECT measurement accuracy of an electrostatic charge was analysed with reference to a switch capacitor configuration model. Consequently, it was found that the electrostatic charge introduced at the bend with sharp angles influenced the ECT results most significantly in pneumatic conveying systems, especially for the cases where a spark was generated. The investigation of spark generation indicated that a strong electrostatic charge can cause major discharges inside or outside the pipeline to damage the experimental instrument in severe cases

Transient performances analysis of wind turbine system with induction generator including flux saturation and skin effect

DEFF Research Database (Denmark)

Li, H.; Zhao, B.; Han, L.

2010-01-01

In order to analyze correctly the effect of different models for induction generators on the transient performances of large wind power generation, Wind turbine driven squirrel cage induction generator (SCIG) models taking into account both main and leakage flux saturation and skin effect were...

Simulation of SOFCs based power generation system using Aspen

Directory of Open Access Journals (Sweden)

Pianko-Oprych Paulina

2017-12-01

Full Text Available This study presents a thermodynamic Aspen simulation model for Solid Oxide Fuel Cells, SOFCs, based power generation system. In the first step, a steady-state SOFCs system model was developed. The model includes the electrochemistry and the diffusion phenomena. The electrochemical model gives good agreement with experimental data in a wide operating range. Then, a parametric study has been conducted to estimate effects of the oxygen to carbon ratio, O/C, on reformer temperature, fuel cell temperature, fuel utilization, overall fuel cell performance, and the results are discussed in this paper. In the second step, a dynamic analysis of SOFCs characteristic has been developed. The aim of dynamic modelling was to find the response of the system against the fuel utilization and the O/C ratio variations. From the simulations, it was concluded that both developed models in the steady and dynamic state were reasonably accurate and can be used for system level optimization studies of the SOFC based power generation system.

ANALYSING SOLAR-WIND HYBRID POWER GENERATING SYSTEM

Directory of Open Access Journals (Sweden)

Mustafa ENGİN

2005-02-01

Full Text Available In this paper, a solar-wind hybrid power generating, system that will be used for security lighting was designed. Hybrid system was installed and solar cells, wind turbine, battery bank, charge regulators and inverter performance values were measured through the whole year. Using measured values of overall system efficiency, reliability, demanded energy cost per kWh were calculated, and percentage of generated energy according to resources were defined. We also include in the paper a discussion of new strategies to improve hybrid power generating system performance and demanded energy cost per kWh.

Generative electronic background music system

Energy Technology Data Exchange (ETDEWEB)

Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

2015-03-10

In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

Generative electronic background music system

International Nuclear Information System (INIS)

Mazurowski, Lukasz

2015-01-01

In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions

Advance monitoring of turbine generators and auxiliary systems

International Nuclear Information System (INIS)

Bloemers, D.

2005-01-01

The STUDIS turbine generator diagnosing system has been designed for diagnosing and early fault detection as a prerequisite for status-dependent preventive maintenance. Based on the data collected in the monitoring part, which are gathered continously, checked extensively and compressed any deviations from normal behavior as well as potential defects are detected and reported in an expert system. In addition, STUDIS can also be used as a mobile system for problem analysis. STUDIS is not meant to replace experts, but is able to relieve them of routine evaluations of defects whose causes and effects as well as symptoms are known, and to make their work more effective. The advanced operating architecture allows unkilled users to detect familiar faults and defects quickly and respond promptly. Experts will find an extensive toolbox above all for complex analyses of malfunctions. The point of departure for operating staff and experts alike is the so-called ''magic eye'', a highly condensed survey of relevant measurement and assessment parameters of the entire turbine generator relative to tolerance bands determined as a function of the operating point. The power of Studies in elucidating faults and defects is explained by a practical case of a blade defect in a gas turbine. (orig.)

Modeling and Simulation of Generator Side Converter of Doubly Fed Induction Generator-Based Wind Power Generation System

DEFF Research Database (Denmark)

Guo, Yougui; Zeng, Ping; Blaabjerg, Frede

2010-01-01

A real wind power generation system is given in this paper. SVM control strategy and vector control is applied for generator side converter and doubly fed induction generator respectively. First the mathematical models of the wind turbine rotor, drive train, generator side converter are described...

Comparison of Power Generating Systems Using Feedback Effect Modeling

International Nuclear Information System (INIS)

Kim, Seong Ho; Kim, Kil Yoo; Kim, Tae Woon

2005-01-01

Comparative assessment of various power systems can be treated as a multicriteria decision-making (MCDM) problem. In reality, there is interdependence among decision elements (e.g., decision goal, decision criteria, and decision alternatives). In our previous work, using an analytic hierarchy process (AHP) technique, a comprehensive assessment framework for national power systems has been developed. It was assumed in the AHP modeling that there is no interdependence among decision elements. In the present work, one of interdependence phenomena, feedback effect, is investigated in the context of network structures instead of one-way directional tree structures. Moreover, attitudes of decision-makers can be incorporated into the feedback effect modeling. The main objectives of this work are to develop a feedback effect modeling using an analytic network process (ANP) technique and to demonstrate the feedback effect using a numerical example in comparison to the hierarchy model

Experimental Study on Effect of Operating Conditions on Thermoelectric Power Generation

DEFF Research Database (Denmark)

Mahmoudi Nezhad, Sajjad; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

2017-01-01

Effect of boundary conditions of thermal reservoirs on power generation of thermoelectric modules (TEMs) is examined experimentally. To realize the characteristics of the power generation by the TEMs, the system performance is studied over various volumetric flow rates and flow temperatures...

Automatic control system generation for robot design validation

Science.gov (United States)

Bacon, James A. (Inventor); English, James D. (Inventor)

2012-01-01

The specification and drawings present a new method, system and software product for and apparatus for generating a robotic validation system for a robot design. The robotic validation system for the robot design of a robotic system is automatically generated by converting a robot design into a generic robotic description using a predetermined format, then generating a control system from the generic robotic description and finally updating robot design parameters of the robotic system with an analysis tool using both the generic robot description and the control system.

Pharmacological Correction of the Negative Effect of Acetylsalicylic Acid on the Energy-Generating System

Directory of Open Access Journals (Sweden)

Vladimir V. Udut, ScD

2012-03-01

Full Text Available The present paper demonstrates the effect of ASA and its combination with SUC on the energy-producing system of rat heart mitochondria as well as an assessment of SUC preventive application effect on ASA pharmacokinetic parameters. Experiments conducted on outbred male albino rats (200-250 g on a model of a xenobiotic load induced by seven days of intragastric injections of acetylsalicylic acid at a dose of 250 mg/kg have shown inhibition of the oxygen consumption rates in the heart mitochondria as well as a limitation of the succinate-dependent substrate oxidation pathways and a decrease in the mitochondria ATP/ADP coefficient. Succinic acid (50 mg/kg for 7 days was injected as a preventive medication to correct the mitochondrial bioenergetics revealed. A comparative research of the pharmacokinetics of acetylsalicylic acid and acetylsalicylic acid against the background of succinic acid performed on the model of rabbits has shown total similarity in the parameters analyzed. This fact demonstrates the possibility of prevention of mitochondrial dysfunction using the intermediate Krebs cycle. SUC as preventive medication promotes the elimination of ASA-induced negative metabolic shifts in the rat heart mitochondria by normalizing the succinate- and NAD-dependent respiration, oxidative phosphorylation, and therefore, it finds good use in the correction of ASA-induced negative side-effects of an energy-generating system

Power control for direct-driven permanent magnet wind generator system with battery storage.

Science.gov (United States)

Guang, Chu Xiao; Ying, Kong

2014-01-01

The objective of this paper is to construct a wind generator system (WGS) loss model that addresses the loss of the wind turbine and the generator. It aims to optimize the maximum effective output power and turbine speed. Given that the wind generator system has inertia and is nonlinear, the dynamic model of the wind generator system takes the advantage of the duty of the Buck converter and employs feedback linearization to design the optimized turbine speed tracking controller and the load power controller. According to that, this paper proposes a dual-mode dynamic coordination strategy based on the auxiliary load to reduce the influence of mode conversion on the lifetime of the battery. Optimized speed and power rapid tracking as well as the reduction of redundant power during mode conversion have gone through the test based on a 5 kW wind generator system test platform. The generator output power as the capture target has also been proved to be efficient.

Power Control for Direct-Driven Permanent Magnet Wind Generator System with Battery Storage

Directory of Open Access Journals (Sweden)

Chu Xiao Guang

2014-01-01

Full Text Available The objective of this paper is to construct a wind generator system (WGS loss model that addresses the loss of the wind turbine and the generator. It aims to optimize the maximum effective output power and turbine speed. Given that the wind generator system has inertia and is nonlinear, the dynamic model of the wind generator system takes the advantage of the duty of the Buck converter and employs feedback linearization to design the optimized turbine speed tracking controller and the load power controller. According to that, this paper proposes a dual-mode dynamic coordination strategy based on the auxiliary load to reduce the influence of mode conversion on the lifetime of the battery. Optimized speed and power rapid tracking as well as the reduction of redundant power during mode conversion have gone through the test based on a 5 kW wind generator system test platform. The generator output power as the capture target has also been proved to be efficient.

Electricity Generation Characteristics of Energy-Harvesting System with Piezoelectric Element Using Mechanical-Acoustic Coupling

Directory of Open Access Journals (Sweden)

Hirotarou Tsuchiya

2016-01-01

Full Text Available This paper describes the electricity generation characteristics of a new energy-harvesting system with piezoelectric elements. The proposed system is composed of a rigid cylinder and thin plates at both ends. The piezoelectric elements are installed at the centers of both plates, and one side of each plate is subjected to a harmonic point force. In this system, vibration energy is converted into electrical energy via electromechanical coupling between the plate vibration and piezoelectric effect. In addition, the plate vibration excited by the point force induces a self-sustained vibration at the other plate via mechanical-acoustic coupling between the plate vibrations and an internal sound field into the cylindrical enclosure. Therefore, the electricity generation characteristics should be considered as an electromechanical-acoustic coupling problem. The characteristics are estimated theoretically and experimentally from the electric power in the electricity generation, the mechanical power supplied to the plate, and the electricity generation efficiency that is derived from the ratio of both power. In particular, the electricity generation efficiency is one of the most appropriate factors to evaluate a performance of electricity generation systems. Thus, the effect of mechanical-acoustic coupling is principally evaluated by examining the electricity generation efficiency.

Stabilization of Wind Energy Conversion System with Hydrogen Generator by Using EDLC Energy Storage System

Science.gov (United States)

Shishido, Seiji; Takahashi, Rion; Murata, Toshiaki; Tamura, Junji; Sugimasa, Masatoshi; Komura, Akiyoshi; Futami, Motoo; Ichinose, Masaya; Ide, Kazumasa

The spread of wind power generation is progressed hugely in recent years from a viewpoint of environmental problems including global warming. Though wind power is considered as a very prospective energy source, wind power fluctuation due to the random fluctuation of wind speed has still created some problems. Therefore, research has been performed how to smooth the wind power fluctuation. This paper proposes Energy Capacitor System (ECS) for the smoothing of wind power which consists of Electric Double-Layer Capacitor (EDLC) and power electronics devices and works as an electric power storage system. Moreover, hydrogen has received much attention in recent years from a viewpoint of exhaustion problem of fossil fuel. Therefore it is also proposed that a hydrogen generator is installed at the wind farm to generate hydrogen. In this paper, the effectiveness of the proposed system is verified by the simulation analyses using PSCAD/EMTDC.

Nanostructured, complex hydride systems for hydrogen generation

Directory of Open Access Journals (Sweden)

Robert A. Varin

2015-02-01

Full Text Available Complex hydride systems for hydrogen (H2 generation for supplying fuel cells are being reviewed. In the first group, the hydride systems that are capable of generating H2 through a mechanical dehydrogenation phenomenon at the ambient temperature are discussed. There are few quite diverse systems in this group such as lithium alanate (LiAlH4 with the following additives: nanoiron (n-Fe, lithium amide (LiNH2 (a hydride/hydride system and manganese chloride MnCl2 (a hydride/halide system. Another hydride/hydride system consists of lithium amide (LiNH2 and magnesium hydride (MgH2, and finally, there is a LiBH4-FeCl2 (hydride/halide system. These hydride systems are capable of releasing from ~4 to 7 wt.% H2 at the ambient temperature during a reasonably short duration of ball milling. The second group encompasses systems that generate H2 at slightly elevated temperature (up to 100 °C. In this group lithium alanate (LiAlH4 ball milled with the nano-Fe and nano-TiN/TiC/ZrC additives is a prominent system that can relatively quickly generate up to 7 wt.% H2 at 100 °C. The other hydride is manganese borohydride (Mn(BH42 obtained by mechano-chemical activation synthesis (MCAS. In a ball milled (2LiBH4 + MnCl2 nanocomposite, Mn(BH42 co-existing with LiCl can desorb ~4.5 wt.% H2 at 100 °C within a reasonable duration of dehydrogenation. Practical application aspects of hydride systems for H2 generation/storage are also briefly discussed.

Thermodynamic analysis of a solar-based multi-generation system with hydrogen production

International Nuclear Information System (INIS)

Ozturk, Murat; Dincer, Ibrahim

2013-01-01

Thermodynamic analysis of a renewable-based multi-generation energy production system which produces a number of outputs, such as power, heating, cooling, hot water, hydrogen and oxygen is conducted. This solar-based multi-generation system consists of four main sub-systems: Rankine cycle, organic Rankine cycle, absorption cooling and heating, and hydrogen production and utilization. Exergy destruction ratios and rates, power or heat transfer rates, energy and exergy efficiencies of the system components are carried out. Some parametric studies are performed in order to examine the effects of varying operating conditions (e.g., reference temperature, direct solar radiation and receiver temperature) on the exergy efficiencies of the sub-systems as well as the whole system. The solar-based multi-generation system which has an exergy efficiency of 57.35%, is obtained to be higher than using these sub-systems separately. The evaluation of the exergy efficiency and exergy destruction for the sub-systems and the overall system show that the parabolic dish collectors have the highest exergy destruction rate among constituent parts of the solar-based multi-generation system, due to high temperature difference between the working fluid and collector receivers. -- Highlights: ► Development of a new multi-generation system for solar-based hydrogen production. ► Investigation of exergy efficiencies and destructions in each process of the system. ► Evaluation of varying operating conditions on the exergy destruction and efficiency

Computer-generated display system guidelines. Volume 2. Developing an evaluation plan

International Nuclear Information System (INIS)

1984-09-01

Volume 1 of this report provides guidance to utilities on the design of displays and the selection and retrofit of a computer-generated display system in the control room of an operating nuclear power plant. Volume 2 provides guidance on planning and managing empirical evaluation of computer-generated display systems, particularly when these displays are primary elements of computer-based operator aids. The guidance provided is in terms of a multilevel evaluation methodology that enables sequential consideration of three primary issues: (1) compatibility; (2) understandability; and (3) effectiveness. The evaluation process approaches these three issues with a top-down review of system objectives, functions, tasks, and information requirements. The process then moves bottom-up from lower-level to higher-level issues, employing different evaluation methods at each level in order to maximize the efficiency and effectiveness of the evaluation process

Steam generator tube rupture effects on a LOCA

International Nuclear Information System (INIS)

LaChance, J.L.

1979-01-01

A problem currently experienced in commercial operating pressurized water reactors (PWR) in the United States is the degradation of steam generator tubes. Safety questions have arisen concerning the effect of these degraded tubes rupturing during a postulated loss-of-coolant accident (LOCA). To determine the effect of a small number of tube ruptures on the behavior of a large PWR during a postulated LOCA, a series of computer simulations was performed. The primary concern of the study was to determine whether a small number (10 or less of steam generator tubes rupturing at the beginning surface temperatures. Additional reflood analyses were performed to determine the system behavior when from 10 to 60 tubes rupture at the beginning of core reflood. The FLOOD4 code was selected as being the most applicable code for use in this study after an extensive analysis of the capabilities of existing codes to perform simulations of a LOCA with concurrent steam generator tube ruptures. The results of the study indicate that the rupturing of 10 or less steam generator tubes in any of the steam generators during a 200% cold leg break will not result in a significant increase in the peak cladding temperature. However, because of the vaporization of the steam generator secondary water in the primary side of the steam generator, a significant increase in the core pressure occurs which retards the reflooding process

Cuypers : a semi-automatic hypermedia generation system

NARCIS (Netherlands)

J.R. van Ossenbruggen (Jacco); F.J. Cornelissen; J.P.T.M. Geurts (Joost); L. Rutledge (Lloyd); L. Hardman (Lynda)

2000-01-01

textabstractThe report describes the architecture of emph{Cuypers, a system supporting second and third generation Web-based multimedia. First generation Web-content encodes information in handwritten (HTML) Web pages. Second generation Web content generates HTML pages on demand, e.g. by filling in

An expert system for steam generator maintenance

International Nuclear Information System (INIS)

Remond, A.

1988-01-01

The tube bundles in PWR steam generators are, by far, the major source of problems whether they are due to primary and secondary side corrosion mechanisms or to tube vibration-induced wear at tube support locations. Because of differences in SG operating, materials, and fabrication processes, the damage may differ from steam generator to steam generator. MPGV, an expert system for steam generator maintenance uses all steam generator data containing data on materials, fabrication processes, inservice inspection, and water chemistry. It has access to operational data for individual steam generators and contains models of possible degradation mechanisms. The objectives of the system are: · Diagnosing the most probable degradation mechanism or mechanisms by reviewing the entire steam generator history. · Identifying the tubes most exposed to future damage and evaluating the urgency of repair by simulating the probable development of the problem in time. · Establishing the appropriate preventive actions such as repair, inspection or other measures and establishing an action schedule. The system is intended for utilities either for individual plants before each inspection outage or any time an incident occurs or for a set of plants through a central MPGV center. (author)

Synthetic wind speed scenarios generation for probabilistic analysis of hybrid energy systems

International Nuclear Information System (INIS)

Chen, Jun; Rabiti, Cristian

2017-01-01

Hybrid energy systems consisting of multiple energy inputs and multiple energy outputs have been proposed to be an effective element to enable ever increasing penetration of clean energy. In order to better understand the dynamic and probabilistic behavior of hybrid energy systems, this paper proposes a model combining Fourier series and autoregressive moving average (ARMA) to characterize historical weather measurements and to generate synthetic weather (e.g., wind speed) data. In particular, Fourier series is used to characterize the seasonal trend in historical data, while ARMA is applied to capture the autocorrelation in residue time series (e.g., measurements with seasonal trends subtracted). The generated synthetic wind speed data is then utilized to perform probabilistic analysis of a particular hybrid energy system configuration, which consists of nuclear power plant, wind farm, battery storage, natural gas boiler, and chemical plant. Requirements on component ramping rate, economic and environmental impacts of hybrid energy systems, and the effects of deploying different sizes of batteries in smoothing renewable variability, are all investigated. - Highlights: • Computational model to synthesize artificial wind speed data with consistent characteristics with database. • Fourier series to capture seasonal trends in the database. • Monte Carlo simulation and probabilistic analysis of hybrid energy systems. • Investigation of the effect of battery in smoothing variability of wind power generation.

Automatic motion inhibit system for a nuclear power generating system

International Nuclear Information System (INIS)

Musick, C.R.; Torres, J.M.

1977-01-01

Disclosed is an automatic motion inhibit system for a nuclear power generating system for inhibiting automatic motion of the control elements to reduce reactor power in response to a turbine load reduction. The system generates a final reactor power level setpoint signal which is continuously compared with a reactor power signal. The final reactor power level setpoint is a setpoint within the capacity of the bypass valves to bypass steam which in no event is lower in value than the lower limit of automatic control of the reactor. If the final reactor power level setpoint is greater than the reactor power, an inhibit signal is generated to inhibit automatic control of the reactor. 6 claims, 5 figures

Thermoelectric generator cooling system and method of control

Science.gov (United States)

Prior, Gregory P; Meisner, Gregory P; Glassford, Daniel B

2012-10-16

An apparatus is provided that includes a thermoelectric generator and an exhaust gas system operatively connected to the thermoelectric generator to heat a portion of the thermoelectric generator with exhaust gas flow through the thermoelectric generator. A coolant system is operatively connected to the thermoelectric generator to cool another portion of the thermoelectric generator with coolant flow through the thermoelectric generator. At least one valve is controllable to cause the coolant flow through the thermoelectric generator in a direction that opposes a direction of the exhaust gas flow under a first set of operating conditions and to cause the coolant flow through the thermoelectric generator in the direction of exhaust gas flow under a second set of operating conditions.

Stability improvement of induction generator-based wind turbine systems

DEFF Research Database (Denmark)

Chen, Zhe; Hu, Y.; Blaabjerg, Frede

2007-01-01

The stability improvement of induction-generator-based wind turbine systems under power system fault conditions has been studied. Two types of generators are considered, namely rotor short-circuited induction generators and dynamic slip-controlled wound rotor induction generators. The factors...... affecting the stability are analysed. The characteristics of the induction-generator-based wind turbines are described, and possible methods of improving stability of the wind generators are discussed. The system modelling is presented, and then the discussed methods of improving stability are investigated...

An analysis of hybrid power generation systems for a residential load

Directory of Open Access Journals (Sweden)

Ceran Bartosz

2017-01-01

Full Text Available This paper presents the results of an energetic and economical analysis of a hybrid power generation system (HPGS which utilises photovoltaic modules, wind turbines, fuel cells and an electrolyzer with hydrogen tank working as the energy storage. The analysis was carried out for three different residential loads, local solar radiation and local wind speed, based on the real measurement values. The analysis shows the optimal solution and the limits of the investment costs required for the system construction. The presented results confirm the effectiveness of the proposed approach, which could be assumed as a very useful tool in the design and analysis of a hybrid power generation system.

Performance evaluation of a tri-generation system with simulation and experiment

International Nuclear Information System (INIS)

Ge, Y.T.; Tassou, S.A.; Chaer, I.; Suguartha, N.

2009-01-01

A test rig for a tri-generation system was set up in the laboratory to investigate the system performance and application feasibility. The rig was composed of three modules, a power component containing a microturbine, a refrigeration unit consisting of an absorption chiller with gas pipe connection, and a supermarket section containing a display cabinet. This system was supposed to be effectively applied into a supermarket energy control system where cooling, heating and electricity power are simultaneously required and subsequently, valuable test results have been produced. In the mean time, a simulation model for the particular tri-generation system has been established by integrating the component models of the system in accordance with the components' actual flow paths and energy streams. These component models, which include a compressor, recuperator, combustion chamber, gas turbine, electric generator, gas pipes, generator (desorber), rectifier, absorbers, condenser and evaporator etc., were developed based upon the balance of heat and mass. The calculations of heat transfer and phase equilibrium were included in the component models and chemical reaction balances were considered in the model of the combustion chamber. The system model has been validated with the test results and has consequently been used to predict the system performance at different operating and design conditions, such as varied ambient temperature, fuel flow rate and pressure ratio etc. The ultimate results of the performance analysis formulated by the system model can contribute significantly to the optimal component and system designs in various practical applications.

Development of a framework for the neutronics analysis system for next generation (3)

International Nuclear Information System (INIS)

Yokoyama, Kenji; Hirai, Yasushi; Hyoudou, Hideaki; Tatsumi, Masahiro

2010-02-01

Development of innovative analysis methods and models in fundamental studies for next-generation nuclear reactor systems is in progress. In order to efficiently and effectively reflect the latest analysis methods and models to primary design of commercial reactor and/or in-core fuel management for power reactors, a next-generation analysis system MARBLE has been developed. The next-generation analysis system provides solutions to the following requirements: (1) flexibility, extensibility and user-friendliness that can apply new methods and models rapidly and effectively for fundamental studies, (2) quantitative proof of solution accuracy and adaptive scoping range for design studies, (3) coupling analysis among different study domains for the purpose of rationalization of plant systems and improvement of reliability, (4) maintainability and reusability for system extensions for the purpose of total quality management and development efficiency. The next-generation analysis system supports many fields, such as thermal-hydraulic analysis, structure analysis, reactor physics etc., and now we are studying reactor physics analysis system for fast reactor in advance. As for reactor physics analysis methods for fast reactor, we have established the JUPITER standard analysis methods based on the past study. But, there has been a problem of extreme inefficiency due to lack of functionality in the conventional analysis system when changing analysis targets and/or modeling levels. That is why, we have developed the next-generation analysis system for reactor physics which reproduces the JUPITER standard analysis method that has been developed so far and newly realizes burnup and design analysis for fast reactor and functions for cross section adjustment. In the present study, we examined in detail the existing design and implementation of ZPPR critical experiment analysis database followed by unification of models within the framework of the next-generation analysis system by

Chemistry management of generator stator water system

International Nuclear Information System (INIS)

Sankar, N.; Santhanam, V.S.; Ayyar, S.R.; Umapathi, P.; Jeena, P.; Hari Krishna, K.; Rajendran, D.

2015-01-01

Chemistry management of water cooled turbine generators with hollow copper conductors is very essential to avoid possible re-deposition of released copper oxides on stator windings, which otherwise may cause flow restrictions by partial plugging of copper hollow conductors and impair cooling. The phenomenon which is of more concern is not strictly of corrosion failure, but the consequences caused by the re-deposition of copper oxides that were formed by reaction of copper with oxygen. There were also some Operating experiences (OE) related to Copper oxide fouling in the system resulting shut down/off-line of plants. In Madras Atomic Power Station (MAPS), the turbine generator stator windings are of Copper material and cooled by demineralized water passing through the hollow conductors. The heated water from the stator is cooled by process water. A part of the stator water is continuously passed through a mixed bed polisher to remove any soluble ionic contaminants to maintain the purity of system water and also maintain copper content as low as possible to avoid possible re-deposition of released copper oxides on stator windings. The chemistry regime employed is neutral water with dissolved oxygen content between 1000-2000 ppb. Chemistry management of Stator water system was reviewed to know its effectiveness. Detailed chemical analyses of the spent resins from the polishing unit were carried out in various campaigns which indicated only part exhaustion of the polishing unit resins and reasonably low levels of copper entrapment in the resins, thus highlighting the effectiveness of the in-practice chemistry regime. (author)

Adaptive Dynamic Surface Control for Generator Excitation Control System

Directory of Open Access Journals (Sweden)

Zhang Xiu-yu

2014-01-01

Full Text Available For the generator excitation control system which is equipped with static var compensator (SVC and unknown parameters, a novel adaptive dynamic surface control scheme is proposed based on neural network and tracking error transformed function with the following features: (1 the transformation of the excitation generator model to the linear systems is omitted; (2 the prespecified performance of the tracking error can be guaranteed by combining with the tracking error transformed function; (3 the computational burden is greatly reduced by estimating the norm of the weighted vector of neural network instead of the weighted vector itself; therefore, it is more suitable for the real time control; and (4 the explosion of complicity problem inherent in the backstepping control can be eliminated. It is proved that the new scheme can make the system semiglobally uniformly ultimately bounded. Simulation results show the effectiveness of this control scheme.

Performance diagnostic system for emergency diesel generators

International Nuclear Information System (INIS)

Logan, K.P.

1991-01-01

Diesel generators are commonly used for emergency backup power at nuclear stations. Emergency diesel generators (EDGs) are subject to both start-up and operating failures, due to infrequent and fast-start use. EDG reliability can be critical to plant safety, particularly when station blackout occurs. This paper describes an expert diagnostic system designed to consistently evaluate the operating performance of diesel generators. The prototype system is comprised of a suite of sensor monitoring, cylinder combustion analyzing, and diagnostic workstation computers. On-demand assessments of generator and auxiliary equipment performance are provided along with color trend displays comparing measured performance to reference-normal conditions

Robust Power Management Control for Stand-Alone Hybrid Power Generation System

International Nuclear Information System (INIS)

Kamal, Elkhatib; Adouane, Lounis; Aitouche, Abdel; Mohammed, Walaa

2017-01-01

This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method. (paper)

Tunable high-order-sideband generation and carrier-envelope-phase-dependent effects via microwave fields in hybrid electro-optomechanical systems

Science.gov (United States)

Si, Liu-Gang; Guo, Ling-Xia; Xiong, Hao; Wu, Ying

2018-02-01

We investigate the high-order-sideband generation (HSG) in a hybrid cavity electro-photomechanical system in which an optical cavity is driven by two optical fields (a monochromatic pump field and a nanosecond Gaussian probe pulse with huge numbers of wave cycles), and at the same time a microwave cavity is driven by a monochromatic ac voltage bias. We show that even if the input powers of two driven optical fields are comparatively low the HSG spectra can be induced and enhanced, and the sideband plateau is extended remarkably with the power of the ac voltage bias increasing. It is also shown that the driven ac voltage bias has profound effects on the carrier-envelope-phase-dependent effects of the HSG in the hybrid cavity electro-photomechanical system. Our research may provide an effective way to control the HSG of optical fields by using microwave fields in cavity optomechanics systems.

Implementation Of L-System In Procedural City Generation Using Java

Directory of Open Access Journals (Sweden)

Surya Sujarwo

2010-12-01

Full Text Available Article discusses about the design and implementation of procedural content generation using java, especially the generation of virtual city. It is applied by using L-System to generate the elements of the city and also using some images as the base models. This method is proven to be more effective because it can produce almost unlimited variations of city in short amount of time without any needs to modify the application. The result of this application is a road map which can be used in many areas such as virtual reality, games, or other related purposes.

Thermodynamic assessment of integrated biogas-based micro-power generation system

International Nuclear Information System (INIS)

Hosseini, Seyed Ehsan; Barzegaravval, Hasan; Wahid, Mazlan Abdul; Ganjehkaviri, Abdolsaeid; Sies, Mohsin Mohd

2016-01-01

Highlights: • A thermodynamic modelling of an integrated biogas-based micro-power generation system is reported. • The impact of design parameters on the thermodynamic performance of the system is evaluated. • High turbine inlet temperatures lead the system to the higher energy and exergy efficiency and higher power generation. • Enhancement of GT isentropic efficiency incurs negative effects on the performance of air preheater and heat exchanger. • The rate of power generation increases by the enhancement of steam turbine pressure in ORC. - Abstract: In this paper, a thermodynamic modelling of an integrated biogas (60%CH_4 + 40%CO_2) micro-power generation system for electricity generation is reported. This system involves a gas turbine cycle and organic Rankine cycle (ORC) where the wasted heat of gas turbine cycle is recovered by closed ORC. The net output power of the micro-power generation system is fixed at 1.4 MW includes 1 MW power generated by GT and 0.4 MW by ORC. Energy and exergy assessments and related parametric studies are carried out, and parameters that influence on energy and exergy efficiency are evaluated. The performance of the system with respect to variation of design parameters such as combustion air inlet temperature, turbine inlet temperature, compressor pressure ratio, gas turbine isentropic efficiency and compressor isentropic efficiency (from the top cycle) and steam turbine inlet pressure, and condenser pressure (from bottoming cycle) is evaluated. The results reveal that by the increase of gas turbine isentropic efficiency, the outlet temperature of gas turbine decreases which incurs negative impacts on the performance of air preheater and heat exchanger, however the energy and exergy efficiency increases in the whole system. By the increase of air compressor pressure ratio, the energy and exergy of the combined cycle decreases. The exergy efficiency of ORC alters by the variation of gas turbine parameters which can be

Anosov C-systems and random number generators

Science.gov (United States)

Savvidy, G. K.

2016-08-01

We further develop our previous proposal to use hyperbolic Anosov C-systems to generate pseudorandom numbers and to use them for efficient Monte Carlo calculations in high energy particle physics. All trajectories of hyperbolic dynamical systems are exponentially unstable, and C-systems therefore have mixing of all orders, a countable Lebesgue spectrum, and a positive Kolmogorov entropy. These exceptional ergodic properties follow from the C-condition introduced by Anosov. This condition defines a rich class of dynamical systems forming an open set in the space of all dynamical systems. An important property of C-systems is that they have a countable set of everywhere dense periodic trajectories and their density increases exponentially with entropy. Of special interest are the C-systems defined on higher-dimensional tori. Such C-systems are excellent candidates for generating pseudorandom numbers that can be used in Monte Carlo calculations. An efficient algorithm was recently constructed that allows generating long C-system trajectories very rapidly. These trajectories have good statistical properties and can be used for calculations in quantum chromodynamics and in high energy particle physics.

The Vulcan pulse generating system

International Nuclear Information System (INIS)

Danson, C.N.; Edwards, C.B.; Wyatt, R.W.W.

1985-01-01

During the past two years several changes have been made to the front end system on the VULCAN pulse generating system. These changes give greater flexibility and a wider choice of operating conditions. This note gives an updated description of the system capabilities, and gives users of the facility an idea of the various pulse combinations that are available. (author)

Distributed generation: remote power systems with advanced storage technologies

International Nuclear Information System (INIS)

Clark, Woodrow; Isherwood, William

2004-01-01

The paper discusses derived from an earlier hypothetical study of remote villiages. It considers the policy implications for communities who have their own local power resources rather than those distributed through transmission from distant sources such as dams, coal power plants or even renewables generation from wind farms, solar thermal or other resources. The issues today, post 911 and the energy crises in California, Northeast North America and Europe, signal the need for a new and different approach to energy supply(s), reliability and dissemination. Distributed generation (DG) as explored in the earlier paper appears to be one such approach that allows for local communities to become energy self-sufficient. Along with energy conservation, efficiency, and on-site generation, local power sources provide concrete definitions and understandings for heretofore ill defined concepts such as sustainability and eco-systems. The end result for any region and nation-state are 'agile energy systems' which use flexible DG, on-site generation and conservation systems meeting the needs of local communities. Now the challenge is to demonstrate and provide economic and policy structures for implementing new advanced technologies for local communities. For institutionalizing economically viable and sound environmental technologies then new finance mechanisms must be established that better reflect the true costs of clean energy distributed in local communities. For example, the aggregation of procurement contracts for on-site solar systems is far more cost effective than for each business owner, public building or household to purchase its own separate units. Thus mass purchasing contracts that are link technologies as hybrids can dramatically reduce costs. In short public-private partnerships can implement the once costly clean energy technologies into local DG systems

Makeup water system performance and impact on PWR steam generator corrosion

International Nuclear Information System (INIS)

Bell, M.J.; Sawocha, S.G.; Smith, L.A.

1984-01-01

The object of this EPRI-funded project was to assess the possible relation of pressurized water reactor (PWR) steam generator corrosion at fresh water sites to makeup water impurity ingress. Makeup water system design, operation and performance reviews were based on site visits, plant design documents, performance records and grab sample analyses. Design features were assessed in terms of their effect on makeup system performance. Attempts were made to correlate the makeup plant source water, system design characteristics, and typical makeup water qualities to steam generator corrosion observations, particularly intergranular attack (IGA). Direct correlations were not made since many variables are involved in the corrosion process and in the case of IGA, the variables have not been clearly established. However, the study did demonstrate that makeup systems can be a significant source of contaminants that are suspected to lead to both IGA and denting. Additionally, it was noted that typical makeup system performance with respect to organic removal was not good. The role of organics in steam generator damage has not been quantified and may deserve further study

Model-Driven Test Generation of Distributed Systems

Science.gov (United States)

Easwaran, Arvind; Hall, Brendan; Schweiker, Kevin

2012-01-01

This report describes a novel test generation technique for distributed systems. Utilizing formal models and formal verification tools, spe cifically the Symbolic Analysis Laboratory (SAL) tool-suite from SRI, we present techniques to generate concurrent test vectors for distrib uted systems. These are initially explored within an informal test validation context and later extended to achieve full MC/DC coverage of the TTEthernet protocol operating within a system-centric context.

Fast pulse beam generation systems for electron accelerators

International Nuclear Information System (INIS)

Koontz, R.F.

1977-01-01

The fast pulse beam generation system to supply the SLAC storage ring, SPEAR, by the two one nanosecond bunch electron beam pulses is described. Generation of these pulses is accomplished with a combination of a fast pulsed grided gun and a synchronized transverse beam chopper. Fast gun based on spherical cathode-grid assembly has output current up to 2As. Fast pulse amplifier system can handle trains of short pulses with repetition rates up to 40 MHz during the 1.6 μs normal accelerating time. Chopping deflector system consists of a resonant coaxial line with the deflecting plates. The resonator frequency is 39.667 MHz. A schematic diagram of the resonant system is shown. The fast beam pickup system has a one hundred picosecond rise time overrall. Fast beam generation and chopper systems permit to generate almost any short or single bunch beam profile needed for experiments

Triple-effect absorption refrigeration system with double-condenser coupling

Science.gov (United States)

DeVault, Robert C.; Biermann, Wendell J.

1993-01-01

A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

Next generation information systems

Energy Technology Data Exchange (ETDEWEB)

Limback, Nathan P [Los Alamos National Laboratory; Medina, Melanie A [Los Alamos National Laboratory; Silva, Michelle E [Los Alamos National Laboratory

2010-01-01

The Information Systems Analysis and Development (ISAD) Team of the Safeguards Systems Group at Los Alamos National Laboratory (LANL) has been developing web based information and knowledge management systems for sixteen years. Our vision is to rapidly and cost effectively provide knowledge management solutions in the form of interactive information systems that help customers organize, archive, post and retrieve nonproliferation and safeguards knowledge and information vital to their success. The team has developed several comprehensive information systems that assist users in the betterment and growth of their organizations and programs. Through our information systems, users are able to streamline operations, increase productivity, and share and access information from diverse geographic locations. The ISAD team is also producing interactive visual models. Interactive visual models provide many benefits to customers beyond the scope of traditional full-scale modeling. We have the ability to simulate a vision that a customer may propose, without the time constraints of traditional engineering modeling tools. Our interactive visual models can be used to access specialized training areas, controlled areas, and highly radioactive areas, as well as review site-specific training for complex facilities, and asset management. Like the information systems that the ISAD team develops, these models can be shared and accessed from any location with access to the internet. The purpose of this paper is to elaborate on the capabilities of information systems and interactive visual models as well as consider the possibility of combining the two capabilities to provide the next generation of infonnation systems. The collection, processing, and integration of data in new ways can contribute to the security of the nation by providing indicators and information for timely action to decrease the traditional and new nuclear threats. Modeling and simulation tied to comprehensive

A methodology for designing flexible multi-generation systems

DEFF Research Database (Denmark)

Lythcke-Jørgensen, Christoffer Ernst; Viana Ensinas, Adriano; Münster, Marie

2016-01-01

An FMG (flexible multi-generation system) consists of integrated and flexibly operated facilities that provide multiple links between the various layers of the energy system. FMGs may facilitate integration and balancing of fluctuating renewable energy sources in the energy system in a cost...... is based on consideration of the following points: Selection, location and dimensioning of processes; systematic heat and mass integration; flexible operation optimization with respect to both short-term market fluctuations and long-term energy system development; global sensitivity and uncertainty...... analysis; biomass supply chains; variable part-load performance; and multi-objective optimization considering economic and environmental performance. Tested in a case study, the methodology is proved effective in screening the solution space for efficient FMG designs, in assessing the importance...

New approach in electricity network regulation: an issue on effective integration of distributed generation in electricity supply systems

International Nuclear Information System (INIS)

Scheepers, Martin J.J.; Wals, Adrian F.

2003-11-01

Technological developments and EU targets for penetration of renewable energy sources (RES) and greenhouse gas (GHG) reduction are decentralising the electricity infrastructure and services. Although, the liberalisation and internationalisation of the European electricity market has resulted in efforts to harmonise transmission pricing and regulation, hardly any initiative exists to consider the opening up and regulation of distribution networks to ensure effective participation of RES and distributed generation (DG) in the internal market. The SUSTELNET project has been created in order to close this policy gap. Its main objective is to develop regulatory roadmaps for the transition to an electricity market and network structure that creates a level playing field between centralised and decentralised generation and that facilitates the integration of RES, within the framework of the liberalisation of the EU electricity market. By analysing the technical, socio-economic and institutional dynamics of the European electricity system and markets, the project identifies the underlying patterns that provide the boundary conditions and levers for policy development to reach long term RES and GHG targets (2020-2030 time frame). This paper presents results of this analytical phase of the SUSTELNET project. Furthermore, preliminary results of the current work in progress are presented. Principles and criteria for a regulatory framework for sustainable electricity systems are discussed, as well as the development of medium to long-term transition strategies/roadmaps for network regulation and market transformation to facilitate the integration of RES and decentralised electricity generating systems.

Performance evaluation of a tri-generation system with simulation and experiment

Energy Technology Data Exchange (ETDEWEB)

Ge, Y.T.; Tassou, S.A.; Suguartha, N. [Mechanical Engineering, School of Engineering and Design, Brunel University, Uxbridge, Middlesex UB8 3PH (United Kingdom); Chaer, I. [Faculty of Engineering, Science and the Built Environment, London South Bank University (T617), Borough Road, London SE1 0AA (United Kingdom)

2009-11-15

A test rig for a tri-generation system was set up in the laboratory to investigate the system performance and application feasibility. The rig was composed of three modules, a power component containing a microturbine, a refrigeration unit consisting of an absorption chiller with gas pipe connection, and a supermarket section containing a display cabinet. This system was supposed to be effectively applied into a supermarket energy control system where cooling, heating and electricity power are simultaneously required and subsequently, valuable test results have been produced. In the mean time, a simulation model for the particular tri-generation system has been established by integrating the component models of the system in accordance with the components' actual flow paths and energy streams. These component models, which include a compressor, recuperator, combustion chamber, gas turbine, electric generator, gas pipes, generator (desorber), rectifier, absorbers, condenser and evaporator etc., were developed based upon the balance of heat and mass. The calculations of heat transfer and phase equilibrium were included in the component models and chemical reaction balances were considered in the model of the combustion chamber. The system model has been validated with the test results and has consequently been used to predict the system performance at different operating and design conditions, such as varied ambient temperature, fuel flow rate and pressure ratio etc. The ultimate results of the performance analysis formulated by the system model can contribute significantly to the optimal component and system designs in various practical applications. (author)

BUILDOUT AND UPGRADE OF CENTRAL EMERGENCY GENERATOR SYSTEM, GENERATOR 3 AND 4 ELECTRICAL INSTALLATION

Energy Technology Data Exchange (ETDEWEB)

Gary D. Seifert; G. Shawn West; Kurt S. Myers; Jim Moncur

2006-07-01

SECTION 01000—SUMMARY OF WORK PART 1—GENERAL 1.1 SUMMARY The work to be performed under this project consists of providing the labor, equipment, and materials to perform "Buildout and Upgrade of Central Emergency Generator System, Generator 3 and 4 Electrical Installation" for the National Aeronautics and Space Administration at the Dryden Flight Research Center (NASA/DFRC), Edwards, California 93523. All modifications to existing substations and electrical distribution systems are the responsibility of the contractor. It is the contractor’s responsibility to supply a complete and functionally operational system. The work shall be performed in accordance with these specifications and the related drawings. The work of this project is defined by the plans and specifications contained and referenced herein. This work specifically includes but is not limited to the following: Scope of Work - Installation 1. Install all electrical wiring and controls for new generators 3 and 4 to match existing electrical installation for generators 1 and 2 and in accordance with drawings. Contractor shall provide as-built details for electrical installation. 2. Install battery charger systems for new generators 3 and 4 to match existing battery charging equipment and installation for generators 1 and 2. This may require exchange of some battery charger parts already on-hand. Supply power to new battery chargers from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. 3. Install electrical wiring for fuel/lube systems for new generators 3 and 4 to match existing installation for generators 1 and 2. Supply power to lube oil heaters and fuel system (day tanks) from panel and breakers as shown on drawings. Utilize existing conduits already routed to generators 3 and 4 to field route the new wiring in the most reasonable way possible. Add any conduits necessary to

A system for long pulse REB generation

International Nuclear Information System (INIS)

Tsuzuki, Tetsuya; Hasegawa, Mitsuru; Narihara, Kazumichi; Tomita, Yukihiro; Kubo, Shin; Kobata, Tadasuke; Mohri, Akihiro.

1987-02-01

A high voltage pulse generator system producing intense relativistic electron beams (REB) (1.5 μs pulse width, 30 kA peak current, 1 MeV energy) was developed to the use of REB ring formation. The system consists of a Marx generator, a transmission line with plastics-water hybrid insulators and a magnetically insulated transmission line connected with a cathode. The system has been well operated more than twenty thousands shots without troubles. (author)

FY 1998 Report on development of large-scale wind power generation systems. Part 1. Operational research on large-scale wind power generation systems; 1998 nendo ogata furyoku hatsuden system kaihatsu seika hokokusho. 1. Ogata furyoku hatsuden system no unten kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

The research and development project is implemented for large-scale wind power generation systems, and the FY 1998 results are reported. In the FY 1998, a slip property variable generator is actually mounted on the wind power generator, to conduct various types of demonstration tests. The reliability validation tests include microstructure examinations, fatigue tests and fatigue strength tests to predict residual strength in the blade. It is confirmed that the blade has a sufficient residual strength. The performance validation tests include continuous measurement of power outputs and wind velocities, and analysis of the output fluctuations. The power output performance during winter when the west wind prevails is higher than designed. In the tests for evaluating the characteristics of the system on which a slip property variable generator is mounted, the output smoothing effect is confirmed in a range beyond the rated output. The wind power generation system is continuously operated, to accumulate the operational data for, e.g., capacity factor, operating time rate, and system failure status. The FY 1998 results are 920,000kWh as the output and 21% as capacity factor. The other items investigate include aerodynamic noise reduction countermeasures, fatigue life of the wind turbine blades, economics of wind power generation, and dismantling and reuse of the wind turbines. (NEDO)

Characterization of the loss allocation techniques for radial systems with distributed generation

International Nuclear Information System (INIS)

Carpaneto, Enrico; Chicco, Gianfranco; Sumaili Akilimali, Jean

2008-01-01

In the restructured electricity industry, meaningful loss allocation methods are required in order to send correct signals to the market taking into account the location and characteristics of loads and generations, including the local sources forming the distributed generation (DG). This paper addresses the issues related to loss allocation in radial distribution systems with DG, with a three-fold focus. First, the key differences in the formulation of the loss allocation problem for radial distribution systems with respect to transmission systems are discussed, specifying the modeling and computational issues concerning the treatment of the slack node in radial distribution systems. Then, the characteristics of derivative-based and circuit-based loss allocation techniques are presented and compared, illustrating the arrangements used for adapting the various techniques to be applied to radial distribution systems with DG. Finally, the effects of introducing voltage-controllable local generation on the calculation of the loss allocation coefficients are discussed, proposing the adoption of a ''reduced'' representation of the system capable of taking into proper account the characteristics of the nodes containing voltage-controllable DG units. Numerical results are provided to show the time evolution of the loss allocation coefficients for distribution systems with variable load and local generation patterns. (author)

Commissioning of the JET flywheel-generator-convertor systems

International Nuclear Information System (INIS)

Huart, M.

1985-01-01

The JET Power Supply Scheme relies on a combination of generator convertors and mains driven transformer rectifiers to supply power to the four major pulse loads, namely the toroidal field coils, the poloidal field coils, the plasma positioning coils and the additional heating. The availability of a network with considerable pulse capability has allowed the generator-convertors to be dedicated, one to the poloidal field coils and the other to the toroidal field coils, thus making possible the use of diode in the output AC/DC convertors. Moreover, it has allowed the use of high p.u. machine reactance compatible with the pulse duty. The extent of supply covered by the Contract, awarded to GEC Large Machine Ltd of Rugby, includes the generators, driving/braking system, excitation system, control-monitoring and protection system, cooling system, output AC/DC convertors, inductors and DC busbars as well as all generator auxiliaries and cabling. Both generators were specified identical to reduce design, tool and spare costs

Power generator system for HCL reaction

International Nuclear Information System (INIS)

Scragg, R. L.; Parker, A. B.

1984-01-01

A power generation system includes a nuclear reactor having a core which in addition to generating heat generates a high frequency electromagnetic radiation. An electromagnetic radiation chamber is positioned to receive at least a portion of the radiation generated by the reactor core. Hydrogen and chlorine are connected into the electromagnetic reactor chamber and react with controlled explosive violence when exposed to the radiation from the nuclear reactor. Oxygen is fed into the reactor chamber as a control medium. The resulting gases under high pressure and temperature are utilized to drive a gas turbine generators. In an alternative embodiment the highly ionized gases, hydrogen and chlorine are utilized as a fluid medium for use in magnetohydrodynamic generators which are attached to the electromagnetic reactor chambers

Cuypers : a semi-automatic hypermedia generation system

OpenAIRE

Ossenbruggen, Jacco; Cornelissen, F.J.; Geurts, Joost; Rutledge, Lloyd; Hardman, Lynda

2000-01-01

textabstractThe report describes the architecture of emph{Cuypers, a system supporting second and third generation Web-based multimedia. First generation Web-content encodes information in handwritten (HTML) Web pages. Second generation Web content generates HTML pages on demand, e.g. by filling in templates with content retrieved dynamically from a database or transformation of structured documents using style sheets (e.g. XSLT). Third generation Web pages will make use of rich markup (e.g. ...

Fuel cell using a hydrogen generation system

Science.gov (United States)

Dentinger, Paul M.; Crowell, Jeffrey A. W.

2010-10-19

A system is described for storing and generating hydrogen and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

Second law analysis of double effect vapour absorption cooler system

International Nuclear Information System (INIS)

Gomri, Rabah; Hakimi, Riad

2008-01-01

In this paper, exergy analysis of double effect lithium bromide/water absorption refrigeration system is presented. The system consists of a second effect generator between the generator and condenser of the single effect absorption refrigeration system, including two solution heat exchangers between the absorber and the two generators. In order to simulate the refrigeration system by using a computer, a new set of computationally efficient formulations of thermodynamic properties of lithium bromide/water solution developed is used. The exergy analysis is carried out for each component of the system. All exergy losses that exist in double effect lithium bromide/water absorption system are calculated. In addition to the coefficient of performance and the exergetic efficiency of the system, the number of exergy of each component of the system is also estimated. This study suggests the component of the absorption refrigeration system that should be developed. The results show that the performance of the system increases with increasing low pressure generator (LPG) temperature, but decreases with increasing high pressure generator (HPG) temperature. The highest exergy loss occurs in the absorber and in the HPG, which therefore makes the absorber and HPG the most important components of the double effect refrigeration system

Innovated feed water distributing system of VVER steam generators

International Nuclear Information System (INIS)

Matal, O.; Sousek, P.; Simo, T.; Lehota, M.; Lipka, J.; Slugen, V.

2000-01-01

Defects in feed water distributing system due to corrosion-erosion effects have been observed at many VVER 440 steam generators (SG). Therefore analysis of defects origin and consequently design development and testing of a new feed water distributing system were performed. System tests in-situ supported by calculations and comparison of measured and calculated data were focused on demonstration of long term reliable operation, definition of water flow and water chemical characteristics at the SG secondary side and their measurements and study of dynamic characteristics needed for the innovated feed water distributing system seismic features approval. The innovated feed water distributing system was installed in the SGs of two VVER units already. (author)

Generating units performances: power system requirements

Energy Technology Data Exchange (ETDEWEB)

Fourment, C; Girard, N; Lefebvre, H

1994-08-01

The part of generating units within the power system is more than providing power and energy. Their performance are not only measured by their energy efficiency and availability. Namely, there is a strong interaction between the generating units and the power system. The units are essential components of the system: for a given load profile the frequency variation follows directly from the behaviour of the units and their ability to adapt their power output. In the same way, the voltage at the units terminals are the key points to which the voltage profile at each node of the network is linked through the active and especially the reactive power flows. Therefore, the customer will experience the frequency and voltage variations induced by the units behaviour. Moreover, in case of adverse conditions, if the units do not operate as well as expected or trip, a portion of the system, may be the whole system, may collapse. The limitation of the performance of a unit has two kinds of consequences. Firstly, it may result in an increased amount of not supplied energy or loss of load probability: for example if the primary reserve is not sufficient, a generator tripping may lead to an abnormal frequency deviation, and load may have to be shed to restore the balance. Secondly, the limitation of a unit performance results in an economic over-cost for the system: for instance, if not enough `cheap` units are able to load-following, other units with higher operating costs have to be started up. We would like to stress the interest for the operators and design teams of the units on the one hand, and the operators and design teams of the system on the other hand, of dialog and information exchange, in operation but also at the conception stage, in order to find a satisfactory compromise between the system requirements and the consequences for the generating units. (authors). 11 refs., 4 figs.

Morphological effect of a scallop shell on a flapping-type tidal stream generator

International Nuclear Information System (INIS)

Le, Tuyen Quang; Ko, Jin Hwan; Byun, Doyoung

2013-01-01

Inspired by nature, flapping-type tidal stream generators have been introduced in recent years. The improvement in their power generation ability is known to be a critical factor in the success of these generators. So far, corrugation and camber observed in flying insects and swimming animals are known to enhance the performance of a flapping-type propulsive system. In this study, we explore the effect of corrugation and camber in a system that mimics a scallop shell in terms of its ability to extract flow energy through a two-dimensional Navier–Stokes simulation. The simulations show that the size and the activity of the leading edge vortex are strongly affected by the morphological factors of the mimicked foils, the effects of which are then advantageous in terms of the power efficiency of the flapping-type tidal stream generator. Eventually, an optimal mimicked foil, as suggested based on the morphological effects, would be a good alternative type of foil with a typical section with regard to the hydrodynamic performance and structural properties of tidal stream generators. (paper)

Liquid metal MHD generator systems

International Nuclear Information System (INIS)

Satyamurthy, P.; Dixit, N.S.; Venkataramani, N.; Rohatgi, V.K.

1985-01-01

Liquid Metal MHD (LMMHD) Generator Systems are becoming increasingly important in space and terrestrial applications due to their compactness and versatility. This report gives the current status and economic viability of LMMHD generators coupled to solar collectors, fast breeder reactors, low grade heat sources and conventional high grade heat sources. The various thermodynamic cycles in the temperatures range of 100degC-2000degC have been examined. The report also discusses the present understanding of various loss mechanisms inherent in LMMHD systems and the techniques for overcoming these losses. A small mercury-air LMMHD experimental facility being set up in Plasma Physics Division along with proposals for future development of this new technology is also presented in this report. (author)

Oxidative degradation of lignin by photochemical and chemical radical generating systems

International Nuclear Information System (INIS)

Gold, M.H.; Kutsuki, H.; Morgan, M.A.

1983-01-01

Oxidation of specifically radiolabeled 14 C-lignins by UV/H 2 O 2 , Fenton's reagent, photosensitizing riboflavin, UV- and γ-irradiation was examined. In the presence of UV/H 2 O 2 , a hydroxyl radical (radicalOH) generating system, 14 C-methoxy, 2-[ 14 C-sidechain] and 14 C-ring labeled lignin were rapidly and extensively degraded as measured by gel filtration of the reaction products on Sephadex LH-20. This suggested that exposure to radicalOH leads to rapid, nonspecific lignin degradation. Rapid degradation of 14 C-methoxy, 2-[ 14 C-sidechain] and 14 C-ring labeled lignin also occurred in the presence of the radicalOH generating system, Fenton's reagent, confirming the primary role of radicalOH in these reactions. Photosensitizing riboflavin, also capable of effecting transformation of organic compounds via Type I hydrogen radical abstractions, caused extensive oxidative degradation of 14 C-methoxy labeled lignin and significant degradation of 2-[ 14 C-sidechain] and 14 C-ring labeled lignin. In addition, UV- and γ-irradiation caused slower but extensive degradation of the polymers, probably via radical type mechanisms. All of these results indicate that radicalOH as well as organic radical generating systems are effective agents for the purpose of degrading this heterogeneous, optically inactive and random biopolymer. (author)

Dynamic Protective Control Strategy for Distributed Generation System with Fixed-speed Wind Turbines

Institute of Scientific and Technical Information of China (English)

2012-01-01

The characteristics of induction generator based fixed-speed wind turbines （FSWT） are investigated. The impacts of different execution time in protective operations are studied under different fauit duration and various wind velocity situations, e.g. , FSWT stabilities of load shedding in distribution systems. Based on this research, a dynamic protective control strategy for a distributed generation system （DGS） with FSWT is proposed. Finally, simulation results demonstrate the effectiveness of the strategy.

Power generation systems and methods

Science.gov (United States)

Jones, Jack A. (Inventor); Chao, Yi (Inventor)

2011-01-01

A power generation system includes a plurality of submerged mechanical devices. Each device includes a pump that can be powered, in operation, by mechanical energy to output a pressurized output liquid flow in a conduit. Main output conduits are connected with the device conduits to combine pressurized output flows output from the submerged mechanical devices into a lower number of pressurized flows. These flows are delivered to a location remote of the submerged mechanical devices for power generation.

Your Co-author Received 150 Citations: Pride, but Not Envy, Mediates the Effect of System-Generated Achievement Messages on Motivation.

Science.gov (United States)

Utz, Sonja; Muscanell, Nicole L

2018-01-01

ResearchGate, a social network site for academics, prominently displays the achievements of people one follows ("With 150 new reads, X was the most read author from their institute"). The goal of this paper was to examine the emotional and motivational effects of these system-generated messages, thereby extending prior research on envy-evoking status updates on Facebook to a professional context. We also extend the research on social comparisons and more broadly, on emotional responses elicited by social media. Specifically, social media research has largely focused on examining emotional reactions to content that is both generated by and is about others. In this research we directly examine updates generated by the system (ResearchGate) while also directly comparing reactions to updates about others' achievements with reactions to updates that are about the self-i.e., one's personal achievements which are also displayed on ResearchGate ("With 150 new reads, you were the most read author from your institute"). Particular attention was paid to the mediating role of envy and pride. The results of our quasi-experimental field study ( n = 419) showed that the achievements of others elicited envy, whereas personal achievements elicited pride. People exposed to their personal achievements (vs. the achievement of others) showed a higher motivation to work harder. This effect was mediated by pride, but not envy. The theoretical and practical implications of these findings are discussed.

Policy-induced market introduction of Generation IV reactor systems

International Nuclear Information System (INIS)

Heek, Aliki Irina van; Roelofs, Ferry

2011-01-01

Almost 10 years ago the U.S. Department of Energy (DOE) started the Generation IV Initiative (GenIV) with 9 other national governments with a positive ground attitude towards nuclear energy. Some of these Generation IV systems, like the fast reactors, are nearing the demonstration stage. The question on how their market introduction will be implemented becomes increasingly urgent. One main topic for future reactor technologies is the treatment of radioactive waste products. Technological solutions to this issue are being developed. One possible process is the transformation of long-living radioactive nuclides into short living ones; a process known as transmutation, which can be done in a nuclear reactor only. Various Generation IV reactor concepts are suitable for this process, and of these systems most experience has been gained with the sodium-cooled fast reactor (SFR). However, both these first generation SFR plants and their Generation IV successors are designed as electricity generating plants, and therefore supposed to be commercially viable in the electricity markets. Various studies indicate that the generation costs of a combined LWR-(S)FR nuclear generating park (LWR: light water reactor) will be higher than that of an LWR-only park. To investigate the effects of the deployment of the different reactors and fuel cycles on the waste produced, resources used and costs incurred as a function of time, a dynamic fuel cycle assessment is performed. This study will focus on the waste impact of the introduction of a fraction of fast reactors in the European nuclear reactor park with a cost increase as described in the previous paragraph. The nuclear fuel cycle scenario code DANESS is used for this, as well as the nuclear park model of the EU-27 used for the previous study. (orig.)

Detailed Modeling and Irreversible Transfer Process Analysis of a Multi-Element Thermoelectric Generator System

Science.gov (United States)

Xiao, Heng; Gou, Xiaolong; Yang, Suwen

2011-05-01

Thermoelectric (TE) power generation technology, due to its several advantages, is becoming a noteworthy research direction. Many researchers conduct their performance analysis and optimization of TE devices and related applications based on the generalized thermoelectric energy balance equations. These generalized TE equations involve the internal irreversibility of Joule heating inside the thermoelectric device and heat leakage through the thermoelectric couple leg. However, it is assumed that the thermoelectric generator (TEG) is thermally isolated from the surroundings except for the heat flows at the cold and hot junctions. Since the thermoelectric generator is a multi-element device in practice, being composed of many fundamental TE couple legs, the effect of heat transfer between the TE couple leg and the ambient environment is not negligible. In this paper, based on basic theories of thermoelectric power generation and thermal science, detailed modeling of a thermoelectric generator taking account of the phenomenon of energy loss from the TE couple leg is reported. The revised generalized thermoelectric energy balance equations considering the effect of heat transfer between the TE couple leg and the ambient environment have been derived. Furthermore, characteristics of a multi-element thermoelectric generator with irreversibility have been investigated on the basis of the new derived TE equations. In the present investigation, second-law-based thermodynamic analysis (exergy analysis) has been applied to the irreversible heat transfer process in particular. It is found that the existence of the irreversible heat convection process causes a large loss of heat exergy in the TEG system, and using thermoelectric generators for low-grade waste heat recovery has promising potential. The results of irreversibility analysis, especially irreversible effects on generator system performance, based on the system model established in detail have guiding significance for

Performance analyses of a hybrid geothermal–fossil power generation system using low-enthalpy geothermal resources

International Nuclear Information System (INIS)

Liu, Qiang; Shang, Linlin; Duan, Yuanyuan

2016-01-01

Highlights: • Geothermal energy is used to preheat the feedwater in a coal-fired power unit. • The performance of a hybrid geothermal–fossil power generation system is analyzed. • Models for both parallel and serial geothermal preheating schemes are presented. • Effects of geothermal source temperatures, distances and heat losses are analyzed. • Power increase of the hybrid system over an ORC and tipping distance are discussed. - Abstract: Low-enthalpy geothermal heat can be efficiently utilized for feedwater preheating in coal-fired power plants by replacing some of the high-grade steam that can then be used to generate more power. This study analyzes a hybrid geothermal–fossil power generation system including a supercritical 1000 MW power unit and a geothermal feedwater preheating system. This study models for parallel and serial geothermal preheating schemes and analyzes the thermodynamic performance of the hybrid geothermal–fossil power generation system for various geothermal resource temperatures. The models are used to analyze the effects of the temperature matching between the geothermal water and the feedwater, the heat losses and pumping power during the geothermal water transport and the resource distance and temperature on the power increase to improve the power generation. The serial geothermal preheating (SGP) scheme generally generates more additional power than the parallel geothermal preheating (PGP) scheme for geothermal resource temperatures of 100–130 °C, but the SGP scheme generates slightly less additional power than the PGP scheme when the feedwater is preheated to as high a temperature as possible before entering the deaerator for geothermal resource temperatures higher than 140 °C. The additional power decreases as the geothermal source distance increases since the pipeline pumping power increases and the geothermal water temperature decreases due to heat losses. More than 50% of the power decrease is due to geothermal

The generation IV nuclear reactor systems - Energy of future

International Nuclear Information System (INIS)

Ohai, Dumitru; Jianu, Adrian

2006-01-01

Ten nations joined within the Generation IV International Forum (GIF), agreeing on a framework for international cooperation in research. Their goal is to develop future-generation nuclear energy systems that can be licensed, constructed, and operated in an economically competitive way while addressing the issues of safety, proliferation, and other public perception concerns. The objective is for the Gen IV systems to be available for deployment by 2030. Using more than 100 nuclear experts from its 10 member nations, the GIF has developed a Gen IV Technology Roadmap to guide the research and development of the world's most advanced, efficient and safe nuclear power systems. The Gen IV Technology Roadmap calls for extensive research and development of six different potential future reactor systems. These include water-cooled, gas-cooled, liquid metal-cooled and nonclassical systems. One or more of these reactor systems will provide the best combination of safety, reliability, efficiency and proliferation resistance at a competitive cost. The main goals for the Gen IV Nuclear Energy Systems are: - Provide sustainable energy generation that meets clean air objectives and promotes long-term availability of systems and effective fuel use for worldwide energy production; - Minimize and manage their nuclear waste and noticeably reduce the long-term stewardship burden in the future, improving the protection of public health and the environment; - Increase the assurance that these reactors are very unattractive and the least desirable route for diversion or theft of weapons-usable materials, and provide increased protection against acts of terrorism; - Have a clear life-cycle cost advantage over other energy sources; - Have a level of financial risk comparable to other energy projects; - Excel in safety and reliability; - Have a low likelihood and degree of reactor core damage. (authors)

Radioisotope Thermoelectric Generator Transport Trailer System

International Nuclear Information System (INIS)

Ard, K.E.; King, D.A.; Leigh, H.; Satoh, J.A.

1994-01-01

The Radioisotope Thermoelectric Generator (RTG) Transportation System, designated as System 100, comprises four major systems. The four major systems are designated as the Packaging System (System 120), Trailer System (System 140), Operations and Ancillary Equipment System system 160), and Shipping and Receiving Facility Transport System (System 180). Packaging System (System 120), including the RTG packaging is licensed (regulatory) hardware; it is certified by the US Department of Energy to be in accordance with Title 10, Code of federal Regulations, Part 71 (10 CFR 71). System 140, System 160, and System 180 are nonlicensed (nonregulatory) hardware

Assessment of government support for the household adoption of micro-generation systems in Korea

International Nuclear Information System (INIS)

Jeong, Gicheol

2013-01-01

This paper investigates how Korean government support affects household adoption of renewable energy-based micro-generation systems by analyzing household preferences in relation to the costs and benefits of system installation and different kinds of government support. The research adopts a discrete choice experiment approach and focuses on two micro-generation technologies: solar voltaic and solar thermal. Our empirical analysis revealed firstly that households prefer micro-generation systems that have low installation costs but high energy saving benefits and long warranty periods; and secondly that households prefer direct subsidies to low-interest loans. However, we also found that households are reluctant to install photovoltaic or solar thermal systems in reality because they see the cost of system installation as being higher than the benefits they would receive from such installation. In short, while existing government supports are somewhat effective in promoting household adoption of micro-generation systems, there also exists the obstacle that the majority of households are unwilling to install such systems despite government support. Thus several policy improvements, which focus on increasing the benefits and decreasing the installation costs of micro-generation systems, are suggested in this paper. -- Highlights: •We investigate how government support affects household adoption of micro-generation. •We analyze household preferences for the costs and benefits of micro-generation system installation. •System with low install costs but high energy saving benefits and long warranty periods are preferred. •Households prefer direct subsidies to low-interest loans. •But the majority of households are unwilling to install systems despite government support

Cascade system using both trough system and dish system for power generation

International Nuclear Information System (INIS)

Zhang, Cheng; Zhang, Yanping; Arauzo, Inmaculada; Gao, Wei; Zou, Chongzhe

2017-01-01

Highlights: • A novel solar cascade system using both trough and dish collectors is proposed. • Heat rejected by the Stirling engines is collected by the condensed water. • The directions to increase the efficiency improvement has been pointed out • Influence of flow type of heating/cooling fluids of Stirling engines is considered. - Abstract: This paper represents a novel solar thermal cascade system using both trough and dish systems for power generation. An effective structure using the condensed fluid of Rankine cycle to cool the Stirling engines to use the heat released by Stirling engines was proposed. The cascade system model with different fluid circuits was developed. The models of some important components of the system, such as dish collector, trough collector and Stirling engine array, are presented with detail explanation in this paper. Corresponding stand-alone systems were also developed for comparison. Simulations were conducted with the models to find out efficiency difference between cascade system and corresponding stand-alone systems. The directions to increase the efficiency difference were also considered. Results show that the cascade system can achieve a higher efficiency with a high solar irradiance (>550 W/m"2). The flow type of fluids between heating and cooling Stirling engine array is also required to concern on designing a cascade system with Stirling engine array.

Nigel: A Systemic Grammar for Text Generation.

Science.gov (United States)

1983-02-01

presumed. Basic references on the systemic framework include [Berry 75, Berry 77, Halliday 76a, Halliday 76b, Hudson 76, Halliday 81, de Joia 80...Edinburgh, 1979. [do Joia 80] de Joia , A., and A. Stanton, Terms in Systemic Linguistics, Batsford Academic and Educational, Ltd., London, 1980. -’C...1 A Grammar for Text Generation- -The Challenge ................................. 1 *1.2 A Grammar for Text Generation--The Design

Alternative pathways for angiotensin II generation in the cardiovascular system

Directory of Open Access Journals (Sweden)

C. Becari

2011-09-01

Full Text Available The classical renin-angiotensin system (RAS consists of enzymes and peptides that regulate blood pressure and electrolyte and fluid homeostasis. Angiotensin II (Ang II is one of the most important and extensively studied components of the RAS. The beneficial effects of angiotensin converting enzyme (ACE inhibitors in the treatment of hypertension and heart failure, among other diseases, are well known. However, it has been reported that patients chronically treated with effective doses of these inhibitors do not show suppression of Ang II formation, suggesting the involvement of pathways alternative to ACE in the generation of Ang II. Moreover, the finding that the concentration of Ang II is preserved in the kidney, heart and lungs of mice with an ACE deletion indicates the important role of alternative pathways under basal conditions to maintain the levels of Ang II. Our group has characterized the serine protease elastase-2 as an alternative pathway for Ang II generation from Ang I in rats. A role for elastase-2 in the cardiovascular system was suggested by studies performed in heart and conductance and resistance vessels of normotensive and spontaneously hypertensive rats. This mini-review will highlight the pharmacological aspects of the RAS, emphasizing the role of elastase-2, an alternative pathway for Ang II generation.

Effective stochastic generator with site-dependent interactions

Science.gov (United States)

Khamehchi, Masoumeh; Jafarpour, Farhad H.

2017-11-01

It is known that the stochastic generators of effective processes associated with the unconditioned dynamics of rare events might consist of non-local interactions; however, it can be shown that there are special cases for which these generators can include local interactions. In this paper, we investigate this possibility by considering systems of classical particles moving on a one-dimensional lattice with open boundaries. The particles might have hard-core interactions similar to the particles in an exclusion process, or there can be many arbitrary particles at a single site in a zero-range process. Assuming that the interactions in the original process are local and site-independent, we will show that under certain constraints on the microscopic reaction rules, the stochastic generator of an unconditioned process can be local but site-dependent. As two examples, the asymmetric zero-temperature Glauber model and the A-model with diffusion are presented and studied under the above-mentioned constraints.

Study on low pressure evaporation of fresh water generation system model

Energy Technology Data Exchange (ETDEWEB)

Chung, Han Shik; Wibowo, Supriyanto; Shin, Yong Han; Jeong, Hyo Min [Gyeongsang National University, Tongyeong (Korea, Republic of); Fajar, Berkah [University of Diponegoro, Semarang (Indonesia)

2012-02-15

A low pressure evaporation fresh water generation system is designed for converting brackish water or seawater into fresh water by distillation in low pressure and temperature. Distillation through evaporation of feed water and subsequent vapor condensation as evaporation produced fresh water were studied; tap water was employed as feed water. The system uses the ejector as a vacuum creator of the evaporator, which is one of the most important parts in the distillation process. Hence liquid can be evaporated at a lower temperature than at normal or atmospheric conditions. Various operating conditions, i.e. temperature of feed water and different orifice diameters, were applied in the experiment to investigate the characteristics of the system. It was found that these parameters have a significant effect on the performance of fresh water generation systems with low pressure evaporation.

Effect of diesel generator exhaust pollutants on growth of Vinca ...

African Journals Online (AJOL)

ADOWIE PERE

ABSTRACT: The effects of exhaust pollutants of generator on root and shoot length, root and shoot weight, number of .... single cylinders with cooling system of air dry. The frequency is 50 .... and reproduction along CO2 gradients. Nonlinear.

Design Optimization and Site Matching of Direct-Drive Permanent Magnet Wind Generator Systems

DEFF Research Database (Denmark)

Li, H.; Chen, Zhe

2009-01-01

This paper investigates the possible site matching of the direct-drive wind turbine concepts based on the electromagnetic design optimization of permanent magnet (PM) generator systems. Firstly, the analytical models of a three-phase radial-flux PM generator with a back-to-back power converter...... of the maximum wind energy capture, the rotor diameter and the rated wind speed of a direct-drive wind turbine with the optimum PM generator are determined. The annual energy output (AEO) is also presented using the Weibull density function. Finally, the maximum AEO per cost (AEOPC) of the optimized wind...... are presented. The optimum design models of direct-drive PM wind generation system are developed with an improved genetic algorithm, and a 500-kW direct-drive PM generator for the minimal generator active material cost is compared to demonstrate the effectiveness of the design optimization. Forty-five PM...

Mitigation of steam generator tube rupture in a pressurized water reactor with passive safety systems

Science.gov (United States)

McDermott, Daniel J.; Schrader, Kenneth J.; Schulz, Terry L.

1994-01-01

The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.

Pulsed power generators using an inductive energy storage system

International Nuclear Information System (INIS)

Akiyama, H.; Sueda, T.; Katschinski, U.; Katsuki, S.; Maeda, S.

1996-01-01

The pulsed power generators using an inductive energy storage system are extremely compact and lightweight in comparison with those using a capacitive energy storage system. The reliable and repetitively operated opening switch is necessary to realize the inductive pulsed power generator. Here, the pulsed power generators using the inductive energy storage system, which have been developed in Kumamoto University, are summarized. copyright 1996 American Institute of Physics

Design Optimization and Evaluation of Different Wind Generator Systems

DEFF Research Database (Denmark)

Chen, Zhe; Li, Hui

2008-01-01

. In this paper, seven variable speed constant frequency (VSCF) wind generator systems are investigated, namely permanent magnet synchronous generators with the direct-driven (PMSG_DD), the single-stage gearbox (PMSG_1G) and three-stage gearbox (PMSG_3G) concepts, doubly fed induction generators with the three......With rapid development of wind power technologies and significant growth of wind power capacity installed worldwide, various wind generator systems have been developed and built. The objective of this paper is to evaluate various wind generator systems by optimization designs and comparisons......-stage gearbox (DFIG_3G) and with the single-stage gearbox (DFIG_1G), the electricity excited synchronous generator with the direct-driven (EESG_DD), and the VSCF squirrel cage induction generator with the three-stage gearbox (SCIG_3G). Firstly, the design models of wind turbines, three/single stage gearbox...

A multi-state model for the reliability assessment of a distributed generation system via universal generating function

International Nuclear Information System (INIS)

Li, Yan-Fu; Zio, Enrico

2012-01-01

The current and future developments of electric power systems are pushing the boundaries of reliability assessment to consider distribution networks with renewable generators. Given the stochastic features of these elements, most modeling approaches rely on Monte Carlo simulation. The computational costs associated to the simulation approach force to treating mostly small-sized systems, i.e. with a limited number of lumped components of a given renewable technology (e.g. wind or solar, etc.) whose behavior is described by a binary state, working or failed. In this paper, we propose an analytical multi-state modeling approach for the reliability assessment of distributed generation (DG). The approach allows looking to a number of diverse energy generation technologies distributed on the system. Multiple states are used to describe the randomness in the generation units, due to the stochastic nature of the generation sources and of the mechanical degradation/failure behavior of the generation systems. The universal generating function (UGF) technique is used for the individual component multi-state modeling. A multiplication-type composition operator is introduced to combine the UGFs for the mechanical degradation and renewable generation source states into the UGF of the renewable generator power output. The overall multi-state DG system UGF is then constructed and classical reliability indices (e.g. loss of load expectation (LOLE), expected energy not supplied (EENS)) are computed from the DG system generation and load UGFs. An application of the model is shown on a DG system adapted from the IEEE 34 nodes distribution test feeder.

Simulation on effect of stopping nuclear power generation

International Nuclear Information System (INIS)

Yajima, Masayuki; Kumakura, Osamu; Sakurai, Norihisa; Nagata, Yutaka; Hattori, Tsuneaki

1990-01-01

The effects that the stopping of nuclear power generation exerts on the price of primary energy such as petroleum, LNG and coal and the trend of Japanese energy and economy are analyzed by using the medium term economy forecasting system. In the simulation, the case of stopping nuclear power generation in seven countries of OECD is supposed, and as for the process of stopping, two cases of immediate stopping and stopping by gradual reduction are set up. The models used for the simulation are the world energy model, the competition among energies model and the multiple category model. By the decrease of nuclear power generation, thermal power generation increases, and the demand of fossil fuel increases. As the result, the price of fossil fuel rises (the world energy model), and the price of fossil fuel imported to Japan rises. Also the quantity of fossil fuel import to Japan increase. These price rise and quantity increase exert deflation effect to Japanese economy (the multiple category model). The price rise of fossil fuel affects the competition among energies in Japan through the relative change of secondary energy price (the competition among energies model). The impact to the world and to Japan is discussed. (K.I.)

The effect of turbulence-radiation interaction on radiative entropy generation and heat transfer

International Nuclear Information System (INIS)

Caldas, Miguel; Semiao, Viriato

2007-01-01

The analysis under the second law of thermodynamics is the gateway for optimisation in thermal equipments and systems. Through entropy minimisation techniques it is possible to increase the efficiency and overall performance of all kinds of thermal systems. Radiation, being the dominant mechanism of heat transfer in high-temperature systems, plays a determinant role in entropy generation within such equipments. Turbulence is also known to be a major player in the phenomenon of entropy generation. Therefore, turbulence-radiation interaction is expected to have a determinant effect on entropy generation. However, this is a subject that has not been dealt with so far, at least to the extent of the authors' knowledge. The present work attempts to fill that void, by studying the effect of turbulence-radiation interaction on entropy generation. All calculations are approached in such a way as to make them totally compatible with standard engineering methods for radiative heat transfer, namely the discrete ordinates method. It was found that turbulence-radiation interaction does not significantly change the spatial pattern of entropy generation, or heat transfer, but does change significantly their magnitude, in a way approximately proportional to the square of the intensity of turbulence

Assessment of a novel solid oxide fuel cell tri-generation system for building applications

International Nuclear Information System (INIS)

Elmer, Theo; Worall, Mark; Wu, Shenyi; Riffat, Saffa

2016-01-01

Highlights: • Experimental assessment of a first-of-its-kind tri-generation system. • High tri-generation efficiencies of 68–71%. • Inclusion of liquid desiccant provides efficiency increase of 9–15%. • System only economically viable with a government’s financial support. - Abstract: The paper provides a performance analysis assessment of a novel solid oxide fuel cell (SOFC) liquid desiccant tri-generation system for building applications. The work presented serves to build upon the current literature related to experimental evaluations of SOFC tri-generation systems, particularly in domestic built environment applications. The proposed SOFC liquid desiccant tri-generation system will be the first-of-its-kind. No research activity is reported on the integration of SOFC, or any fuel cell, with liquid desiccant air conditioning in a tri-generation system configuration. The novel tri-generation system is suited to applications that require simultaneous electrical power, heating and dehumidification/cooling. There are several specific benefits to the integration of SOFC and liquid desiccant air conditioning technology, including; very high operational electrical efficiencies even at low system capacities and the ability to utilise low-grade thermal energy in a (useful) cooling process. Furthermore, the novel tri-generation system has the potential to increase thermal energy utilisation and thus the access to the benefits achievable from on-site electrical generation, primarily; reduced emissions and operating costs. Using empirical SOFC and liquid desiccant component data, an energetic, economic and environmental performance analysis assessment of the novel system is presented. Significant conclusions from the work include: (1) SOFC and liquid desiccant are a viable technological pairing in the development of an efficient and effective tri-generation system. High tri-generation efficiencies in the range of 68–71% are attainable. (2) The inclusion of

Comparative assessment of the environmental impact of wastes from electricity generation systems

International Nuclear Information System (INIS)

Torres, C.; Smith, G.M.; Linsley, G.; Hossain, S.

1994-01-01

The paper describes an outline methodology for assessing and comparing the environmental impact arising from management of the wastes from nuclear and other electricity generation systems. The assessment framework is applicable to wastes from all generation systems, including nuclear, fossil and renewable fuel systems, and can also be applied to the management of mixed hazardous waste. The major energy technologies in terms of waste production can be classified according to three major categories of fuels: fossil, nuclear and renewable. The emphasis in this description is on nuclear utility low-level and mixed wastes and waste streams. The methodology may be used to support the project on Data Bases and Methodologies for Comparative Assessment of Different Energy Sources for Electricity Generation (DECADES project, (2)) which is being developed by the International Atomic Energy Agency in collaboration with other international agencies. The DECADES project has the overall objective to improve the abilities for comparative assessment of energy chains for electricity generation. The objective of a methodology such as that described here is to ensure that waste management aspects are included effectively in comparative assessments of energy systems. This paper discusses the waste strams arising from nuclear power plants

Analysis of Wind Speed Forecasting Error Effects on Automatic Generation Control Performance

Directory of Open Access Journals (Sweden)

H. Rajabi Mashhadi

2014-09-01

Full Text Available The main goal of this paper is to study statistical indices and evaluate AGC indices in power system which has large penetration of the WTGs. Increasing penetration of wind turbine generations, needs to study more about impacts of it on power system frequency control. Frequency control is changed with unbalancing real-time system generation and load . Also wind turbine generations have more fluctuations and make system more unbalance. Then AGC loop helps to adjust system frequency and the scheduled tie-line powers. The quality of AGC loop is measured by some indices. A good index is a proper measure shows the AGC performance just as the power system operates. One of well-known measures in literature which was introduced by NERC is Control Performance Standards(CPS. Previously it is claimed that a key factor in CPS index is related to standard deviation of generation error, installed power and frequency response. This paper focuses on impact of a several hours-ahead wind speed forecast error on this factor. Furthermore evaluation of conventional control performances in the power systems with large-scale wind turbine penetration is studied. Effects of wind speed standard deviation and also degree of wind farm penetration are analyzed and importance of mentioned factor are criticized. In addition, influence of mean wind speed forecast error on this factor is investigated. The study system is a two area system which there is significant wind farm in one of those. The results show that mean wind speed forecast error has considerable effect on AGC performance while the mentioned key factor is insensitive to this mean error.

Integrated operation of electric vehicles and renewable generation in a smart distribution system

International Nuclear Information System (INIS)

Zakariazadeh, Alireza; Jadid, Shahram; Siano, Pierluigi

2015-01-01

Highlights: • The contribution of electric vehicles to provide the reserve capacity is analyzed. • Decentralized energy and reserve scheduling in a distribution system is presented. • The integrated operation of renewable generation and electric vehicles is proposed. - Abstract: Distribution system complexity is increasing mainly due to technological innovation, renewable Distributed Generation (DG) and responsive loads. This complexity makes difficult the monitoring, control and operation of distribution networks for Distribution System Operators (DSOs). In order to cope with this complexity, a novel method for the integrated operational planning of a distribution system is presented in this paper. The method introduces the figure of the aggregator, conceived as an intermediate agent between end-users and DSOs. In the proposed method, energy and reserve scheduling is carried out by both aggregators and DSO. Moreover, Electric Vehicles (EVs) are considered as responsive loads that can participate in ancillary service programs by providing reserve to the system. The efficiency of the proposed method is evaluated on an 84-bus distribution test system. Simulation results show that the integrated scheduling of EVs and renewable generators can mitigate the negative effects related to the uncertainty of renewable generation

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Directory of Open Access Journals (Sweden)

Shigang Zhang

2015-10-01

Full Text Available Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics.

Optimal Sequential Diagnostic Strategy Generation Considering Test Placement Cost for Multimode Systems

Science.gov (United States)

Zhang, Shigang; Song, Lijun; Zhang, Wei; Hu, Zheng; Yang, Yongmin

2015-01-01

Sequential fault diagnosis is an approach that realizes fault isolation by executing the optimal test step by step. The strategy used, i.e., the sequential diagnostic strategy, has great influence on diagnostic accuracy and cost. Optimal sequential diagnostic strategy generation is an important step in the process of diagnosis system construction, which has been studied extensively in the literature. However, previous algorithms either are designed for single mode systems or do not consider test placement cost. They are not suitable to solve the sequential diagnostic strategy generation problem considering test placement cost for multimode systems. Therefore, this problem is studied in this paper. A formulation is presented. Two algorithms are proposed, one of which is realized by system transformation and the other is newly designed. Extensive simulations are carried out to test the effectiveness of the algorithms. A real-world system is also presented. All the results show that both of them have the ability to solve the diagnostic strategy generation problem, and they have different characteristics. PMID:26457709

Strategic Generation with Conjectured Transmission Price Responses in a Mixed Transmission Pricing System. Part 2. Application

International Nuclear Information System (INIS)

Wals, A.F.; Hobbs, B.F.; Rijkers, F.A.M.

2004-05-01

The conjectured transmission price response model presented in the first of this two-paper series considers the expectations of oligopolistic generators regarding how demands for transmission services affect the prices of those services. Here, the model is applied to northwest Europe, simulating a mixed transmission pricing system including export fees, a path-based auction system for between-country interfaces, and implicit congestion-based pricing of internal country constraints. The path-based system does not give credit for counterflows when calculating export capability. The application shows that this no-netting policy can exacerbate the economic inefficiencies caused by oligopolistic pricing by generators. The application also illustrates the effects of different generator conjectures regarding rival supply responses and transmission prices. If generators anticipate that their increased demand for transmission services will increase transmission prices, then competitive intensity diminishes and energy prices rise. In the example here, the effect of this anticipation is to double the price increase that results from oligopolistic (Cournot) competition among generators

Simultaneous power generation and heat recovery using a heat pipe assisted thermoelectric generator system

International Nuclear Information System (INIS)

Remeli, Muhammad Fairuz; Tan, Lippong; Date, Abhijit; Singh, Baljit; Akbarzadeh, Aliakbar

2015-01-01

Highlights: • A new passive power cogeneration system using industrial waste heat was introduced. • Heat pipes and thermoelectrics were used for recovering waste heat and electricity. • Theoretical model predicted the 2 kW test rig could recover 1.345 kW thermal power. • 10.39 W electrical power was produced equivalent to 0.77% conversion efficiency. - Abstract: This research explores a new method of recovering waste heat and electricity using a combination of heat pipes and thermoelectric generators (HP-TEG). The HP-TEG system consists of Bismuth Telluride (Bi 2 Te 3 ) based thermoelectric generators (TEGs), which are sandwiched between two finned heat pipes to achieve a temperature gradient across the TEG for thermoelectricity generation. A theoretical model was developed to predict the waste heat recovery and electricity conversion performances of the HP-TEG system under different parametric conditions. The modelling results show that the HP-TEG system has the capability of recovering 1.345 kW of waste heat and generating 10.39 W of electrical power using 8 installed TEGs. An experimental test bench for the HP-TEG system is under development and will be discussed in this paper

Data monitoring system for PV solar generators

International Nuclear Information System (INIS)

Stoev, M.; Katerski, A.; Williams, A.

2000-01-01

The two 1.5 kWp photovoltaic (PV) solar generators are installed and the new PC data monitoring system is developed by applying EC standards for European Solar Test Installation (ESTI). The schematic system diagram of PV generator is presented. The recording parameters for analytical and global monitoring are discussed. The meteorological data from ESTI sensors, temperature sensor and electrical data from inverter and calibrated shunt are stored via analog digital converters (ADC) on a hard disk of data storage PC. Data Logger and Monitor software for automatic data acquisition, treatment and visual distance control of all output PV data from PV solar generator has been created

Loss Allocation in a Distribution System with Distributed Generation Units

DEFF Research Database (Denmark)

Lund, Torsten; Nielsen, Arne Hejde; Sørensen, Poul Ejnar

2007-01-01

In Denmark, a large part of the electricity is produced by wind turbines and combined heat and power plants (CHPs). Most of them are connected to the network through distribution systems. This paper presents a new algorithm for allocation of the losses in a distribution system with distributed...... generation. The algorithm is based on a reduced impedance matrix of the network and current injections from loads and production units. With the algorithm, the effect of the covariance between production and consumption can be evaluated. To verify the theoretical results, a model of the distribution system...

Exterior field evaluation of new generation video motion detection systems

International Nuclear Information System (INIS)

Malone, T.P.

1988-01-01

Recent advancements in video motion detection (VMD) system design and technology have resulted in several new commercial VMD systems. Considerable interest in the new VMD systems has been generated because the systems are advertised to work effectively in exterior applications. Previous VMD systems, when used in an exterior environment, tended to have very high nuisance alarm rates due to weather conditions, wildlife activity and lighting variations. The new VMD systems advertise more advanced processing of the incoming video signal which is aimed at rejecting exterior environmental nuisance alarm sources while maintaining a high detection capability. This paper discusses the results of field testing, in an exterior environment, of two new VMD systems

Very High Frequency Monitoring System for Engine Gearbox and Generator Health Management (Postprint)

National Research Council Canada - National Science Library

Watson, Matthew J; Byington, Carl S; Behbahani, Alireza

2007-01-01

...) vibration monitoring system that integrates various vibro-acoustic data with intelligent feature extraction and fault isolation algorithms to effectively assess engine gearbox and generator health...

Probabilistic generation assessment system of renewable energy in Korea

Directory of Open Access Journals (Sweden)

Yeonchan Lee

2016-01-01

Full Text Available This paper proposes probabilistic generation assessment system introduction of renewable energy generators. This paper is focused on wind turbine generator and solar cell generator. The proposed method uses an assessment model based on probabilistic model considering uncertainty of resources (wind speed and solar radiation. Equivalent generation function of the wind and solar farms are evaluated. The equivalent generation curves of wind farms and solar farms are assessed using regression analysis method using typical least square method from last actual generation data for wind farms. The proposed model is applied to Korea Renewable Generation System of 8 grouped 41 wind farms and 9 grouped around 600 solar farms in South Korea.

Experimental Investigation and Modeling of Integrated Tri-generation Systems

Science.gov (United States)

Cetinkaya, Eda

Energy demand in the world is increasing with population growth and higher living standards. Today, the need for energy requires a focus on renewable sources without abandoning fossil fuels. Efficient use of energy is one of the most important tasks in modern energy systems to achieve. In addition to the energy need, growing environmental concerns are linked with energy is emerged. Multi-purpose energy generation allows a higher efficiency by generating more outputs with the same input in the same system. Tri-generation systems are expected to provide at least three commodities, such as heating, cooling, desalination, storable fuel production and some other useful outputs, in addition to power generation. In this study, an experimental investigation of gasification is presented and two integrated tri-generation systems are proposed. The first integrated tri-generation system (System 1) utilizes solar energy as input and the outputs are power, fresh water and hot water. It consists of four sub-systems, namely solar power tower system, desalination system, Rankine cycle and organic Rankine cycle (ORC). The second integrated tri-generation system (System 2) utilizes coal and biomass as input and the outputs are power, fuel and hot water. It consists of five sub-systems: gasification plant, Brayton cycle, Rankine cycle, Fischer-Tropsch synthesis plant and an organic Rankine cycle (ORC). Experimental investigation includes coal and biomass gasification, where the experimental results of synthesis gas compositions are utilized in the analysis of the second systems. To maximize efficiency, heat losses from the system should be minimized through a recovery system to make the heat a useful commodity for other systems, such as ORCs which can utilize the low-grade heat. In this respect, ORCs are first analyzed for three different configurations in terms of energy and exergy efficiencies altering working fluids to increase the power output. Among two types of coal and one type

The Use of Nuclear Generation to Provide Power System Stability

OpenAIRE

Heather Wyman-Pain; Yuankai Bian; Furong Li

2016-01-01

The decreasing use of fossil fuel power stations has a negative effect on the stability of the electricity systems in many countries. Nuclear power stations have traditionally provided minimal ancillary services to support the system but this must change in the future as they replace fossil fuel generators. This paper explains the development of the four most popular reactor types still in regular operation across the world which have formed the basis for most reactor dev...

Tidal Energy System for On-Shore Power Generation

Energy Technology Data Exchange (ETDEWEB)

Bruce, Allan J

2012-06-26

immersion testing. The COTS pump and motor were selected to scale to MW size and were oversized for the TRL-4 demonstration, operating at only 1-6% of rated values. Nevertheless, in for 2-18 kW drive power, in agreement with manufacturer performance data, we measured efficiencies of 85-90% and 75-80% for the pump and motor, respectively. These efficiencies being 95-96% at higher operating powers. (2) Two follow-on paths were identified. In both cases conventional turbine systems can be modified, replacing existing gear box and generator with a hydraulic pump and on-shore components. On a conventional path, a TRL5/6 15kW turbine system can be engineered and tested on a barge at an existing site in Maine. Alternatively, on an accelerated path, a TRL-8 100kW system can be engineered and tested by modifying a team member's existing MHK turbines, with barge and grid-connected test sites in-place. On both paths the work can be expedited and cost effective by reusing TRL-4 components, modifying existing turbines and using established test sites. (3) Sizing, performance modeling and costing of a scaled 15MW system, suitable for operation in Maine's Western Passage, was performed. COTS components are identified and the performance projections are favorable. The estimated LCOE is comparable to wind generation with peak production at high demand times. (4) We determined that a similar HET approach can be extended to on-shore and off-shore wind turbine systems. These are very large energy resources which can be addressed in parallel for even great National benefit. (5) Preliminary results on this project were presented at two International Conferences on renewable energy in 2012, providing a timely dissemination of information. We have thus demonstrated a proof-in-concept of a novel, tidal HET system that eliminates all submerged gears and electronics to improve reliability. Hydraulic pump efficiencies of 90% have been confirmed in simulated tidal flows between 1 and 3 m

Thermo-electrical systems for the generation of electricity

International Nuclear Information System (INIS)

Bitschi, A.; Froehlich, K.

2010-01-01

This article takes a look at theoretical models concerning thermo-electrical systems for the generation of electricity and demonstrations of technology actually realised. The potentials available and developments are discussed. The efficient use of energy along the whole generation and supply chain, as well as the use of renewable energy sources are considered as being two decisive factors in the attainment of a sustainable energy supply system. The large amount of unused waste heat available today in energy generation, industrial processes, transport systems and public buildings is commented on. Thermo-electric conversion systems are discussed and work being done on the subject at the Swiss Federal Institute of Technology in Zurich is discussed. The findings are discussed and results are presented in graphical form

Performance analysis of a co-generation system using solar energy and SOFC technology

International Nuclear Information System (INIS)

Akikur, R.K.; Saidur, R.; Ping, H.W.; Ullah, K.R.

2014-01-01

Highlights: • A new concept of a cogeneration system is proposed and investigated. • The system comprises solar collector, PV, SOFC and heat exchanger. • 83.6% Power and heat generation efficiency has been found at fuel cell mode. • 85.1% Efficiency of SOSE has been found at H2 production mode. • The heat to power ratio of SOFC mode has been found about 0.917. - Abstract: Due to the increasing future energy demands and global warming, the renewable alternative energy sources and the efficient power systems have been getting importance over the last few decades. Among the renewable energy technologies, the solar energy coupling with fuel cell technology will be the promising possibilities for the future green energy solutions. Fuel cell cogeneration is an auspicious technology that can potentially reduce the energy consumption and environmental impact associated with serving building electrical and thermal demands. In this study, performance assessment of a co-generation system is presented to deliver electrical and thermal energy using the solar energy and the reversible solid oxide fuel cell. A mathematical model of the co-generation system is developed. To illustrate the performance, the system is considered in three operation modes: a solar-solid oxide fuel cell (SOFC) mode, which is low solar radiation time when the solar photovoltaic (PV) and SOFC are used for electric and heat load supply; a solar-solid oxide steam electrolyzer (SOSE) mode, which is high solar radiation time when PV is used for power supply to the electrical load and to the steam electrolyzer to generate hydrogen (H 2 ); and a SOFC mode, which is the power and heat generation mode of reversible SOFC using the storage H 2 at night time. Also the effects of solar radiation on the system performances and the effects of temperature on RSOFC are analyzed. In this study, 100 kW electric loads are considered and analyzed for the power and heat generation in those three modes to evaluate

Next generation surveillance system (NGSS)

International Nuclear Information System (INIS)

Aparo, Massimo

2006-01-01

Development of 'functional requirements' for transparency systems may offer a near-term mode of regional cooperation. New requirements under development at the IAEA may provide a foundation for this potential activity. The Next Generation Surveillance System (NGSS) will become the new IAEA remote monitoring system Under new requirements the NGSS would attempt to use more commercial components to reduce cost, increase radiation survivability and further increase reliability. The NGSS must be available in two years due to rapidly approaching obsolescence in the existing DCM family. (author)

Macroscopic effects in attosecond pulse generation

International Nuclear Information System (INIS)

Ruchon, T; Varju, K; Mansten, E; Swoboda, M; L'Huillier, A; Hauri, C P; Lopez-Martens, R

2008-01-01

We examine how the generation and propagation of high-order harmonics in a partly ionized gas medium affect their strength and synchronization. The temporal properties of the resulting attosecond pulses generated in long gas targets can be significantly influenced by macroscopic effects, in particular by the intensity in the medium and the degree of ionization which control the dispersion. Under some conditions, the use of gas targets longer than the absorption length can lead to the generation of compressed attosecond pulses. We show these macroscopic effects experimentally, using a 6 mm-long argon-filled gas cell as the generating medium

Macroscopic effects in attosecond pulse generation

Energy Technology Data Exchange (ETDEWEB)

Ruchon, T; Varju, K; Mansten, E; Swoboda, M; L' Huillier, A [Department of Physics, Lund University, PO Box 118, SE-221 00 Lund (Sweden); Hauri, C P; Lopez-Martens, R [Laboratoire d' Optique Appliquee, Ecole Nationale Superieure des Techniques Avancees (ENSTA)-Ecole Polytechnique CNRS UMR 7639, 91761 Palaiseau (France)], E-mail: anne.lhuillier@fysik.lth.se

2008-02-15

We examine how the generation and propagation of high-order harmonics in a partly ionized gas medium affect their strength and synchronization. The temporal properties of the resulting attosecond pulses generated in long gas targets can be significantly influenced by macroscopic effects, in particular by the intensity in the medium and the degree of ionization which control the dispersion. Under some conditions, the use of gas targets longer than the absorption length can lead to the generation of compressed attosecond pulses. We show these macroscopic effects experimentally, using a 6 mm-long argon-filled gas cell as the generating medium.

Your Co-author Received 150 Citations: Pride, but Not Envy, Mediates the Effect of System-Generated Achievement Messages on Motivation

Science.gov (United States)

Utz, Sonja; Muscanell, Nicole L.

2018-01-01

ResearchGate, a social network site for academics, prominently displays the achievements of people one follows (“With 150 new reads, X was the most read author from their institute”). The goal of this paper was to examine the emotional and motivational effects of these system-generated messages, thereby extending prior research on envy-evoking status updates on Facebook to a professional context. We also extend the research on social comparisons and more broadly, on emotional responses elicited by social media. Specifically, social media research has largely focused on examining emotional reactions to content that is both generated by and is about others. In this research we directly examine updates generated by the system (ResearchGate) while also directly comparing reactions to updates about others’ achievements with reactions to updates that are about the self—i.e., one’s personal achievements which are also displayed on ResearchGate (“With 150 new reads, you were the most read author from your institute”). Particular attention was paid to the mediating role of envy and pride. The results of our quasi-experimental field study (n = 419) showed that the achievements of others elicited envy, whereas personal achievements elicited pride. People exposed to their personal achievements (vs. the achievement of others) showed a higher motivation to work harder. This effect was mediated by pride, but not envy. The theoretical and practical implications of these findings are discussed. PMID:29780339

Your Co-author Received 150 Citations: Pride, but Not Envy, Mediates the Effect of System-Generated Achievement Messages on Motivation

Directory of Open Access Journals (Sweden)

Sonja Utz

2018-05-01

Full Text Available ResearchGate, a social network site for academics, prominently displays the achievements of people one follows (“With 150 new reads, X was the most read author from their institute”. The goal of this paper was to examine the emotional and motivational effects of these system-generated messages, thereby extending prior research on envy-evoking status updates on Facebook to a professional context. We also extend the research on social comparisons and more broadly, on emotional responses elicited by social media. Specifically, social media research has largely focused on examining emotional reactions to content that is both generated by and is about others. In this research we directly examine updates generated by the system (ResearchGate while also directly comparing reactions to updates about others’ achievements with reactions to updates that are about the self—i.e., one’s personal achievements which are also displayed on ResearchGate (“With 150 new reads, you were the most read author from your institute”. Particular attention was paid to the mediating role of envy and pride. The results of our quasi-experimental field study (n = 419 showed that the achievements of others elicited envy, whereas personal achievements elicited pride. People exposed to their personal achievements (vs. the achievement of others showed a higher motivation to work harder. This effect was mediated by pride, but not envy. The theoretical and practical implications of these findings are discussed.

A third generation mobile high energy radiography system

International Nuclear Information System (INIS)

Fry, D.A.; Valdez, J.E.; Johnson, C.S.; Kimerly, H.J.; Vananne, J.R.

1997-01-01

A third generation mobile high energy radiographic capability has been completed and put into service by the Los Alamos National Laboratory. The system includes a 6 MeV linac x-ray generator, Co-60 gamma source, all-terrain transportation, on-board power, real-time radiography (RTR), a control center, and a complete darkroom capability. The latest version includes upgraded and enhanced portability, flexibility, all-terrain operation, all-weather operation, and ease of use features learned from experience with the first and second generation systems. All systems were required to have the following characteristics; all-terrain, all-weather operation, self-powered, USAF airlift compatible, reliable, simple to setup, easy to operate, and all components two-person portable. The systems have met these characteristics to differing degrees, as is discussed in the following section, with the latest system being the most capable

Fiscal 1998 research report. Feasibility study on next-generation environment-friendly urban transport systems; 1998 nendo chosa hokokusho. Jisedai kankyo kyosei toshi kotsu system donyu kanosei chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This research arranges recent public transport system technologies such as LRT, and clarifies their technical issues to be overcome and developmental courses, and the improvement effect of their energy efficiency and CO{sub 2} reduction effect by such measures to contribute to development of next-generation public transport systems. The outlines and features of LRT, monorail/trolley bus and AGT as existing public transport systems are arranged. In the EU, development of tramways using rubber tires is in promotion. The concept of a next-generation environment- friendly urban transport system is prepared based on features of every public transport system. Since a trolley system causes traffic congestion and environment deterioration, introduction of an independent transport system with fuel cell is necessary in the future. The technical issues and solutions for construction of the next-generation transport systems are analyzed. Fuel cell and ITS are important candidates. Substitution of the next-generation transport system for existing buses showed a CO{sub 2} reduction effect of 3.91 Mton/y in Japan. (NEDO)

Synchronization Methods for Three Phase Distributed Power Generation Systems

DEFF Research Database (Denmark)

Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

2005-01-01

Nowadays, it is a general trend to increase the electricity production using Distributed Power Generation Systems (DPGS) based on renewable energy resources such as wind, sun or hydrogen. If these systems are not properly controlled, their connection to the utility network can generate problems...... on the grid side. Therefore, considerations about power generation, safe running and grid synchronization must be done before connecting these systems to the utility network. This paper is mainly dealing with the grid synchronization issues of distributed systems. An overview of the synchronization methods...

Electrical system design and reliability at Ontario Hydro nuclear generating stations

Energy Technology Data Exchange (ETDEWEB)

Royce, C. J. [Ontario Hydro, 700 University Avenue, Toronto, Ontario M5G 1X6 (Canada)

1986-02-15

This paper provides an overview of design practice and the predicted and actual reliability of electrical station service Systems at Ontario Nuclear Generating Stations. Operational experience and licensing changes have indicated the desirability of improving reliability in certain instances. For example, the requirement to start large emergency coolant injection pumps resulted in the turbine generator units in a multi-unit station being used as a back-up power supply. Results of reliability analyses are discussed. To mitigate the effects of common mode events Ontario Hydro adopted a 'two group' approach to the design of safety related Systems. This 'two group' approach is reviewed and a single fully environmentally qualified standby power supply is proposed for future use. (author)

Design and optimization of flexible multi-generation systems

DEFF Research Database (Denmark)

Lythcke-Jørgensen, Christoffer Ernst

variations and dynamics, and energy system analysis, which fails to consider process integration synergies in local systems. The primary objective of the thesis is to derive a methodology for linking process design practices with energy system analysis for enabling coherent and holistic design optimization...... of flexible multi-generation system. In addition, the case study results emphasize the importance of considering flexible operation, systematic process integration, and systematic assessment of uncertainties in the design optimization. It is recommended that future research focus on assessing system impacts...... from flexible multi-generation systems and performance improvements from storage options....

Stator Current Harmonic Reduction in a Novel Half Quasi-Z-Source Wind Power Generation System

Directory of Open Access Journals (Sweden)

Shoudao Huang

2016-09-01

Full Text Available The generator stator current gets distorted with unacceptable levels of total harmonic distortion (THD because impedance-source wind power generation systems use three-phase diode rectifiers. The stator current harmonics will cause increasing losses and torque ripple, which reduce the efficiency and stability of the system. This paper proposes a novel half quasi-Z-source inverter (H-qZSI for grid-connected wind power generation systems, which can reduce the generator stator current harmonics a great deal. When H-qZSI operates in the shoot-through zero state, the derivative of the generator stator current is only determined by the instantaneous value of the generator stator voltage, so the nonlinear relationship between generator stator current and stator voltage is improved compared with the traditional impedance-source inverter. Theoretically, it is indicated that the stator current harmonics can be reduced effectively by means of the proposed H-qZSI. Finally, simulation and experimental results are given to verify the theoretical analysis.

Avoided operating costs in thermal generating systems

International Nuclear Information System (INIS)

Chowdhury, N.; Billinton, R.; Gupta, R.

1995-01-01

A simple and straightforward technique was developed to assess avoided system operating costs associated with non-utility generation (NUG). The technique was based on optimum loading configurations of the committed units both before and after the inclusion of NUG energy. The salient features of the technique were presented in this paper. Assessment of avoided operating cost with deterministic and probabilistic criteria were explained. A time differentiated price system was adopted in the algorithms to reflect the different value placed on purchased price by a utility at different times of the day. The algorithms show the utility effects of dispatchable and non-dispatchable NUG energies. The IEEE Reliability Test System (RTS) was utilized for numerical analysis. Results were illustrated. It was found that sensitivity studies similar to those performed on the IEEE-RTS could be utilized to determine the amount of energy and the time period during which utilities and NUGs can maximize their economic benefits. 7 refs., 5 figs., 1 tab

Electric distribution systems and embedded generation capacity

International Nuclear Information System (INIS)

Calderaro, V.; Galdi, V.; Piccolo, A.; Siano, P.

2006-01-01

The main policy issues of European States are sustainable energy supply promotion and liberalization of energy markets, which introduced market competition in electricity production and created support mechanisms to encourage renewable electricity production and consumption. As a result of liberalization, any generator, including small-scale and renewable energy based units, can sell electricity on the free market. In order to meet future sustainability targets, connection of a higher number of Distributed Generation (DG) units to the electrical power system is expected, requiring changes in the design and operation of distribution electricity systems, as well as changes in electricity network regulation. In order to assist distribution system operators in planning and managing DG connections and in maximizing DG penetration and renewable sources exploitation, this paper proposed a reconfiguration methodology based on a Genetic Algorithm (GA), that was tested on a 70-bus system with DG units. The simulation results confirmed that the methodology represents a suitable tool for distribution system operators when dealing with DG capacity expansion and power loss issues, providing information regarding the potential penetration network-wide and allowing maximum exploitation of renewable generation. 35 refs., 4 tabs., 6 figs

Modeling and Control System Design for an Integrated Solar Generation and Energy Storage System with a Ride-Through Capability: Preprint

Energy Technology Data Exchange (ETDEWEB)

Wang, X.; Yue, M.; Muljadi, E.

2012-09-01

This paper presents a generic approach for PV panel modeling. Data for this modeling can be easily obtained from manufacturer datasheet, which provides a convenient way for the researchers and engineers to investigate the PV integration issues. A two-stage power conversion system (PCS) is adopted in this paper for the PV generation system and a Battery Energy Storage System (BESS) can be connected to the dc-link through a bi-directional dc/dc converter. In this way, the BESS can provide some ancillary services which may be required in the high penetration PV generation scenario. In this paper, the fault ride-through (FRT) capability is specifically focused. The integrated BESS and PV generation system together with the associated control systems is modeled in PSCAD and Matlab platforms and the effectiveness of the controller is validated by the simulation results.

Power system reliability impacts of wind generation and operational reserve requirements

Directory of Open Access Journals (Sweden)

Esteban Gil

2015-06-01

Full Text Available Due to its variability, wind generation integration presents a significant challenge to power system operators in order to maintain adequate reliability levels while ensuring least cost operation. This paper explores the trade-off between the benefits associated to a higher wind penetration and the additional operational reserve requirements that they impose. Such exploration is valued in terms of its effect on power system reliability, measured as an amount of unserved energy. The paper also focuses on how changing the Value of Lost Load (VoLL can be used to attain different reliability targets, and how wind power penetration and the diversity of the wind energy resource will impact quality of supply (in terms of instances of unserved energy. The evaluation of different penetrations of wind power generation, different wind speed profiles, wind resource diversity, and different operational reserve requirements, is conducted on the Chilean Northern Interconnected System (SING using statistical modeling of wind speed time series and computer simulation through a 24-hour ahead unit commitment algorithm and a Monte Carlo simulation scheme. Results for the SING suggest that while wind generation can significantly reduce generation costs, it can also imply higher security costs to reach acceptable reliability levels.

Advanced methodology for generation expansion planning including interconnected systems

Energy Technology Data Exchange (ETDEWEB)

Zhao, M; Yokoyama, R; Yasuda, K [Tokyo Metropolitan Univ. (Japan); Sasaki, H [Hiroshima Univ. (Japan); Ogimoto, K [Electric Power Development Co. Ltd., Tokyo (Japan)

1994-12-31

This paper reviews advanced methodology for generation expansion planning including interconnected systems developed in Japan, putting focus on flexibility and efficiency in a practical application. First, criteria for evaluating flexibility of generation planning considering uncertainties are introduced. Secondly, the flexible generation mix problem is formulated as a multi-objective optimization with more than two objective functions. The multi-objective optimization problem is then transformed into a single objective problem by using the weighting method, to obtain the Pareto optimal solution, and solved by a dynamics programming technique. Thirdly, a new approach for electric generation expansion planning of interconnected systems is presented, based on the Benders Decomposition technique. That is, large scale generation problem constituted by the general economic load dispatch problem, and several sub problems which are composed of smaller scale isolated system generation expansion plans. Finally, the generation expansion plan solved by an artificial neural network is presented. In conclusion, the advantages and disadvantages of this method from the viewpoint of flexibility and applicability to practical generation expansion planning are presented. (author) 29 refs., 10 figs., 4 tabs.

Development of solar power generator system; Taiyoko netsufukugo hatsuden system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Kisara, K; Kumagai, T; Niino, M; Chen, L; Eguchi, K [National Aerospace Laboratory, Tokyo (Japan)

1997-11-25

Described herein is a new hybrid solar power generator system, in which solar energy is separated into the light and heat components by a wavelength-selective filter before being directly converted into electric power, the former for the amorphous solar cell (ASC) unit and the latter for the thermoelectric unit. These units complement with each other to enhance overall efficiency. The ASC unit should have a higher efficiency when it works on the light component, because the heat (infrared) component increases cell temperature and decreases its output. For the ASC unit, the effects of the filter have been tested. The thermoelectric unit, generating power by the Seebeck effect, should have a higher efficiency, if heat flux passing through the unit can be increased, because of increased temperature differential, to which voltage produced increases proportionally. For the thermoelectric unit, heat is collected by a parabolic mirror unit from sunbeams received by a heliostat. Characteristics of these units are grasped almost as expected by the tests. 4 refs., 11 figs., 1 tab.

The effect of introducing increased-reliability-risk electronic components into 3rd generation telecommunications systems

International Nuclear Information System (INIS)

Salmela, Olli

2005-01-01

In this paper, the dependability of 3rd generation telecommunications network systems is studied. Special attention is paid to a case where increased-reliability-risk electronic components are introduced to the system. The paper consists of three parts: First, the reliability data of four electronic components is considered. This includes statistical analysis of the reliability test data, thermo-mechanical finite element analysis of the printed wiring board structures, and based on those, a field reliability estimate of the components is constructed. Second, the component level reliability data is introduced into the network element reliability analysis. This is accomplished by using a reliability block diagram technique and Monte Carlo simulation of the network element. The end result of the second part is a reliability estimate of the network element with and without the high-risk component. Third, the whole 3rd generation network having multiple network elements is analyzed. In this part, the criticality of introducing high-risk electronic components into a 3rd generation telecommunications network is considered

The effect of introducing increased-reliability-risk electronic components into 3rd generation telecommunications systems

Energy Technology Data Exchange (ETDEWEB)

Salmela, Olli [Nokia Networks, P.O. Box 301, 00045 Nokia Group (Finland)]. E-mail: olli.salmela@nokia.com

2005-08-01

In this paper, the dependability of 3rd generation telecommunications network systems is studied. Special attention is paid to a case where increased-reliability-risk electronic components are introduced to the system. The paper consists of three parts: First, the reliability data of four electronic components is considered. This includes statistical analysis of the reliability test data, thermo-mechanical finite element analysis of the printed wiring board structures, and based on those, a field reliability estimate of the components is constructed. Second, the component level reliability data is introduced into the network element reliability analysis. This is accomplished by using a reliability block diagram technique and Monte Carlo simulation of the network element. The end result of the second part is a reliability estimate of the network element with and without the high-risk component. Third, the whole 3rd generation network having multiple network elements is analyzed. In this part, the criticality of introducing high-risk electronic components into a 3rd generation telecommunications network is considered.

Development of an Active Power Reserve Management Method for DC Applied Wave-Wind Combined Generation Systems

Directory of Open Access Journals (Sweden)

Seungmin Jung

2015-11-01

Full Text Available A system that combines a wind turbine and a wave generator can share the off-shore platform and therefore mix the advantages of the transmission system construction and the power conversion system. The current hybrid generation system considers output limitation according to the instructions of the transmission system operator (TSO, and controls the profile using wind turbine pitch control. However, the integrated wave generation system utilizing a DC network does not adapt a power limitation scheme due to its mechanical constraints. In this paper, a control plan focusing on the electrical section of wave generators is formed in order to effectively manage the output profile of the hybrid generation system. The plan pays attention to power reserve flexibility for the utility grid using the analysis of the controllable elements. Comparison with the existing system is performed based on real offshore conditions. With the help of power system computer aided design (PSCAD simulation, the ability of the novel technique is estimated by proposing the real power control based on the reference signal of TSO and the reactive power capacity it produces.

Improvement of adaptive fuzzy control for a photovoltaic/wind/diesel generating system; Taiyoko/furyoku/diesel hatsuden system no saitekigata fuzzy seigyo no kairyo

Energy Technology Data Exchange (ETDEWEB)

Nagaike, H; Kenmoku, Y; Sakakibara, T [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S [Maizuru National College of Technology, Kyoto (Japan); Kawamoto, T [Shizuoka University, Shizuoka (Japan).Faculty of Engineering

1996-10-27

The photovoltaic/wind/diesel generating system that uses a storage battery as auxiliary power has been proposed to supply power from the system to the independent area. In this system, it is important to generate no insufficient power from the viewpoint of effective energy utilization and minimize the fuel consumption of a diesel generator. Authors have proposed the adaptive fuzzy control that changes the shape of the membership function of input variables according to the parameter indicating the system state. However, a parameter was rapidly changed in the conventional method. This badly influences the control. Therefore, the way to determine the parameter that indicates the state of this system was improved. Assume that an input value is set to the average value between a certain point of time and the {Delta}t time as the method for determining a parameter. If the {Delta}t value is lower, the change in a membership function is more effective. As a result, a greater fuel reduction effect was obtained. 4 refs., 8 figs., 1 tab.

Design and Implementation of the Permanent- Magnet Synchronous Generator Drive in Wind Generation Systems

Directory of Open Access Journals (Sweden)

Yuan-Chih Chang

2018-06-01

Full Text Available The design and implementation of the permanent-magnet synchronous generator drive in wind generation systems is presented in this paper. The permanent-magnet synchronous generator (PMSG can converse the alternating current (AC power of the wind turbine to direct current (DC power. In this paper, the dynamic model of a PMSG is first introduced. The current controller is designed based on T-S fuzzy models of the PMSG. The stability of the proposed PMSG drive system is analyzed and proved. The proposed T-S fuzzy current control possesses a disturbance suppression ability. Compared with the traditional fuzzy logic system, its stability can be proved and verified. Finally, the control performance of the PMSG drive is verified by experimental results.

Radio resource management for next generation mobile communication systems

DEFF Research Database (Denmark)

Wang, Hua

The key feature of next generation (4G) mobile communication system is the ability to deliver a variety of multimedia services with different Quality-of-Service (QoS) requirements. Compared to the third generation (3G) mobile communication systems, 4G mobile communication system introduces several...

FY 1977 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Photovoltaic power generation systems); 1977 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-03-31

This project is aimed at investigation on irradiation conditions of natural solar radiation to establish the performance evaluation methods; establishment of standard evaluation methods under natural solar radiation; and investigation on practical problems involved in the photovoltaic power generation systems. The research items are (1) photovoltaic power generation systems, and (2) standard evaluation methods for photovoltaic power generation systems installed on the ground. The item (1) includes the effect analysis in which existing Japanese residential buildings are selected to estimate possibility of installation of photovoltaic power generation systems and possible quantity of power generated; conceptual designs in which several systems conceivable at present are proposed and outlined, and a 30kW photovoltaic power generation system is taken up to investigate, e.g., solar cell arrays for the system, orthogonal conversion devices, associated facilities, conceptual designs of storage batteries, problems involved therein, and future research themes; and operation of the cell, which takes up operational examples of solar cell power sources, and operational problems viewed from the power transmission side. The item (2) proposes the standard evaluation methods (primary drafts) for the solar cell arrays and panels as those for photovoltaic power generation systems installed on the ground. (NEDO)

Characterization and calibration of gas sensor systems at ppb level—a versatile test gas generation system

Science.gov (United States)

Leidinger, Martin; Schultealbert, Caroline; Neu, Julian; Schütze, Andreas; Sauerwald, Tilman

2018-01-01

This article presents a test gas generation system designed to generate ppb level gas concentrations from gas cylinders. The focus is on permanent gases and volatile organic compounds (VOCs) for applications like indoor and outdoor air quality monitoring or breath analysis. In the design and the setup of the system, several issues regarding handling of trace gas concentrations have been considered, addressed and tested. This concerns not only the active fluidic components (flow controllers, valves), which have been chosen specifically for the task, but also the design of the fluidic tubing regarding dead volumes and delay times, which have been simulated for the chosen setup. Different tubing materials have been tested for their adsorption/desorption characteristics regarding naphthalene, a highly relevant gas for indoor air quality monitoring, which has generated high gas exchange times in a previous gas mixing system due to long time adsorption/desorption effects. Residual gas contaminations of the system and the selected carrier air supply have been detected and quantified using both an analytical method (GC-MS analysis according to ISO 16000-6) and a metal oxide semiconductor gas sensor, which detected a maximum contamination equivalent to 28 ppb of carbon monoxide. A measurement strategy for suppressing even this contamination has been devised, which allows the system to be used for gas sensor and gas sensor system characterization and calibration in the low ppb concentration range.

Comparative analysis of cost benefit division methodologies in a hydrothermal generation system

International Nuclear Information System (INIS)

Pereira, M.V.F.; Gorenstin, B.G.; Campodonico, N.M.; Costa, J.P. da; Kelman, J.

1989-01-01

The development and operation planning of the Brazilian generation system has been realized in a coordinate way by several years, due to some organizations, where the main generating companies from the country take part. The benefit share of the system to each participant of the planning and integrated operation has aroused interest. This paper describes the alternate forms of cost benefit allocation, between the participant companies of a coordinate operation, in order to reach an adequateness of remuneration and incentives. It was analysed two proposal of benefit allocation for energy export/import contracts: share by generation value and share by marginal benefit, concluding that the second one represents the best way of contribution for the several factors that comprising a hydroelectric power plant (storage capacity, effective storage and turbine capacity). (C.G.C.). 1 tab

Advanced control of direct-driven PMSG generator in wind turbine system

Directory of Open Access Journals (Sweden)

Gajewski Piotr

2016-12-01

Full Text Available The paper presents the advanced control system of the wind energy conversion with a variable speed wind turbine. The considered system consists of a wind turbine with the permanent magnet synchronous generator (PMSG, machine side converter (MSC, grid side converter (GSC and control circuits. The mathematical models of a wind turbine system, the PMSG generator and converters have been described. The control algorithms of the converter systems based on the methods of vector control have been applied. In the advanced control system of the machine side converter the optimal MPPT control method has been used. Additionally the pitch control scheme is included in order to achieve the limitation of maximum power and to prevent mechanical damage of the wind turbine. In the control system of the grid side converter the control of active and reactive power has been applied with the application of Voltage Oriented Control (VOC. The performance of the considered wind energy system has been studied by digital simulation. The results of simulation studies confirmed the good effectiveness of the considered wind turbine system and very good performance of the proposed methods of vector control and control systems.

Life Support Systems: Oxygen Generation and Recovery

Data.gov (United States)

National Aeronautics and Space Administration — The Advanced Exploration Systems (AES) Life Support Systems project Oxygen Generation and Recovery technology development area encompasses several sub-tasks in an...

CASTOR - Advanced System for VVER Steam Generator Inspection

International Nuclear Information System (INIS)

Mateljak, Petar

2014-01-01

From the safety point of view, steam generator is a very important component of a nuclear power plant. Only a thin tube wall prevents leakage of radioactive material from the primary side into the environment. Therefore, it is very important to perform inspections in order to detect pipe damage and apply appropriate corrective actions during outage. Application of the nondestructive examination (NDE) technique, that can locate degradation and measure its size and orientation, is an integral part of nuclear power plant maintenance. The steam generator inspection system is consisted of remotely controlled manipulator, testing instrument and software for data acquisition and analysis. Recently, the inspection systems have evolved to a much higher level of automation, efficiency and reliability resulting in a lower cost and shorter outage time. Electronic components have become smaller and deal with more complex algorithms. These systems are very fast, precise, reliable and easy to handle. The whole inspection, from the planning, examination, data analysis and final report, is now a highly automated process, which makes inspection much easier and more reliable. This paper presents the new generation of INETEC's VVER steam generator inspection system as ultimate solution for steam generator inspection and repair. (author)

Flexibility-Based Evaluation of Variable Generation Acceptability in Korean Power System

Directory of Open Access Journals (Sweden)

Chang-Gi Min

2017-06-01

Full Text Available This study proposes an evaluation method for variable generation (VG acceptability with an adequate level of power system flexibility. In this method, a risk index referred to as the ramping capability shortage expectation (RSE is used to quantify flexibility. The RSE value of the current power system is selected as the adequate level of flexibility (i.e., RSE criterion. VG acceptability is represented by the VG penetration level for the RSE criterion. The proposed evaluation method was applied to the generation expansion plan in Korea for 2029 in order to examine the validity of the existing plan for VG penetration. Sensitivity analysis was also performed to analyze the effects of changes in system uncertainty on VG acceptability. The results show that the planned VG penetration level for 2029 can improve by approximately 12% while securing flexibility.

NEXT GENERATION TURBINE SYSTEM STUDY

Energy Technology Data Exchange (ETDEWEB)

Frank Macri

2002-02-28

Rolls-Royce has completed a preliminary design and marketing study under a Department of Energy (DOE) cost shared contract (DE-AC26-00NT40852) to analyze the feasibility of developing a clean, high efficiency, and flexible Next Generation Turbine (NGT) system to meet the power generation market needs of the year 2007 and beyond. Rolls-Royce evaluated the full range of its most advanced commercial aerospace and aeroderivative engines alongside the special technologies necessary to achieve the aggressive efficiency, performance, emissions, economic, and flexibility targets desired by the DOE. Heavy emphasis was placed on evaluating the technical risks and the economic viability of various concept and technology options available. This was necessary to ensure the resulting advanced NGT system would provide extensive public benefits and significant customer benefits without introducing unacceptable levels of technical and operational risk that would impair the market acceptance of the resulting product. Two advanced cycle configurations were identified as offering significant advantages over current combined cycle products available in the market. In addition, balance of plant (BOP) technologies, as well as capabilities to improve the reliability, availability, and maintainability (RAM) of industrial gas turbine engines, have been identified. A customer focused survey and economic analysis of a proposed Rolls-Royce NGT product configuration was also accomplished as a part of this research study. The proposed Rolls-Royce NGT solution could offer customers clean, flexible power generation systems with very high efficiencies, similar to combined cycle plants, but at a much lower specific cost, similar to those of simple cycle plants.

Model Oriented Application Generation for Industrial Control Systems

CERN Document Server

Copy, B; Blanco Vinuela, E; Fernandez Adiego, B; Nogueira Ferandes, R; Prieto Barreiro, I

2011-01-01

The CERN Unified Industrial Control Systems framework (UNICOS) is a software generation methodology and a collection of development tools that standardizes the design of industrial control applications [1]. A Software Factory, named the UNICOS Application Builder (UAB) [2], was introduced to ease extensibility and maintenance of the framework, introducing a stable metamodel, a set of platformindependent models and platformspecific configurations against which code generation plugins and configuration generation plugins can be written. Such plugins currently target PLC programming environments (Schneider and SIEMENS PLCs) as well as SIEMENS WinCC Open Architecture SCADA (previously known as ETM PVSS) but are being expanded to cover more and more aspects of process control systems. We present what constitutes the UNICOS metamodel and the models in use, how these models can be used to capture knowledge about industrial control systems and how this knowledge can be leveraged to generate both code and configuratio...

A Heuristic Approach to Distributed Generation Source Allocation for Electrical Power Distribution Systems

Directory of Open Access Journals (Sweden)

M. Sharma

2010-12-01

Full Text Available The recent trends in electrical power distribution system operation and management are aimed at improving system conditions in order to render good service to the customer. The reforms in distribution sector have given major scope for employment of distributed generation (DG resources which will boost the system performance. This paper proposes a heuristic technique for allocation of distribution generation source in a distribution system. The allocation is determined based on overall improvement in network performance parameters like reduction in system losses, improvement in voltage stability, improvement in voltage profile. The proposed Network Performance Enhancement Index (NPEI along with the heuristic rules facilitate determination of feasible location and corresponding capacity of DG source. The developed approach is tested with different test systems to ascertain its effectiveness.

Enhancing the Trajectory Generation of a Stair-Climbing Mobility System

Science.gov (United States)

Chocoteco, Jose Abel

2017-01-01

Recent advances in mobile robotic technologies have enabled significant progress to be made in the development of Stair-Climbing Mobility Systems (SCMSs) for people with mobility impairments and limitations. These devices are mainly characterized by their ability to negotiate those architectural barriers associated with climbing stairs (curbs, ramps, etc.). The development of advanced trajectory generators with which to surpass such architectural barriers is one of the most important aspects of SCMSs that has not yet been appropriately exploited. These advanced trajectory generators have a considerable influence on the time invested in the stair climbing process and on passenger comfort and, consequently, provide people with physical disabilities with greater independence and a higher quality of life. In this paper, we propose a new nonlinear trajectory generator for an SCMS. This generator balances the stair-climbing time and the user’s comfort and includes the most important constraints inherent to the system behavior: the geometry of the architectural barrier, the reconfigurable nature of the SCMS (discontinuous states), SCMS state-transition diagrams, comfort restrictions and physical limitations as regards the actuators, speed and acceleration. The SCMS was tested on a real two-step staircase using different time-comfort combinations and different climbing strategies to verify the effectiveness and the robustness of the proposed approach.

An expert system for automatic mesh generation for Sn particle transport simulation in parallel environment

International Nuclear Information System (INIS)

Apisit, Patchimpattapong; Alireza, Haghighat; Shedlock, D.

2003-01-01

An expert system for generating an effective mesh distribution for the SN particle transport simulation has been developed. This expert system consists of two main parts: 1) an algorithm for generating an effective mesh distribution in a serial environment, and 2) an algorithm for inference of an effective domain decomposition strategy for parallel computing. For the first part, the algorithm prepares an effective mesh distribution considering problem physics and the spatial differencing scheme. For the second part, the algorithm determines a parallel-performance-index (PPI), which is defined as the ratio of the granularity to the degree-of-coupling. The parallel-performance-index provides expected performance of an algorithm depending on computing environment and resources. A large index indicates a high granularity algorithm with relatively low coupling among processors. This expert system has been successfully tested within the PENTRAN (Parallel Environment Neutral-Particle Transport) code system for simulating real-life shielding problems. (authors)

An expert system for automatic mesh generation for Sn particle transport simulation in parallel environment

Energy Technology Data Exchange (ETDEWEB)

Apisit, Patchimpattapong [Electricity Generating Authority of Thailand, Office of Corporate Planning, Bangkruai, Nonthaburi (Thailand); Alireza, Haghighat; Shedlock, D. [Florida Univ., Department of Nuclear and Radiological Engineering, Gainesville, FL (United States)

2003-07-01

An expert system for generating an effective mesh distribution for the SN particle transport simulation has been developed. This expert system consists of two main parts: 1) an algorithm for generating an effective mesh distribution in a serial environment, and 2) an algorithm for inference of an effective domain decomposition strategy for parallel computing. For the first part, the algorithm prepares an effective mesh distribution considering problem physics and the spatial differencing scheme. For the second part, the algorithm determines a parallel-performance-index (PPI), which is defined as the ratio of the granularity to the degree-of-coupling. The parallel-performance-index provides expected performance of an algorithm depending on computing environment and resources. A large index indicates a high granularity algorithm with relatively low coupling among processors. This expert system has been successfully tested within the PENTRAN (Parallel Environment Neutral-Particle Transport) code system for simulating real-life shielding problems. (authors)

Competition and Cooperation of Distributed Generation and Power System

Science.gov (United States)

Miyake, Masatoshi; Nanahara, Toshiya

Advances in distributed generation technologies together with the deregulation of an electric power industry can lead to a massive introduction of distributed generation. Since most of distributed generation will be interconnected to a power system, coordination and competition between distributed generators and large-scale power sources would be a vital issue in realizing a more desirable energy system in the future. This paper analyzes competitions between electric utilities and cogenerators from the viewpoints of economic and energy efficiency based on the simulation results on an energy system including a cogeneration system. First, we examine best response correspondence of an electric utility and a cogenerator with a noncooperative game approach: we obtain a Nash equilibrium point. Secondly, we examine the optimum strategy that attains the highest social surplus and the highest energy efficiency through global optimization.

Reactor trip on turbine trip inhibit control system for nuclear power generating system

International Nuclear Information System (INIS)

Torres, J.M.; Musick, C.R.

1976-01-01

A reactor trip on turbine trip inhibit control system for a nuclear power generating system which utilizes steam bypass valves is described. The control system inhibits a normally automatic reactor trip on turbine trip when the bypass valves have the capability of bypassing enough steam to prevent reactor trip limits from being reached and/or to prevent opening of the secondary safety pressure valves. The control system generates a bypass valve capability signal which is continuously compared with the reactor power. If the capability is greater than the reactor power, then an inhibit signal is generated which prevents a turbine trip signal from tripping the nuclear reactor. 10 claims, 4 figures

Switching control of linear systems for generating chaos

International Nuclear Information System (INIS)

Liu Xinzhi; Teo, Kok-Lay; Zhang Hongtao; Chen Guanrong

2006-01-01

In this paper, a new switching method is developed, which can be applied to generating different types of chaos or chaos-like dynamics from two or more linear systems. A numerical simulation is given to illustrate the generated chaotic dynamic behavior of the systems with some variable parameters. Finally, a circuit is built to realize various chaotic dynamical behaviors

Reliability analysis of wind embedded power generation system for ...

African Journals Online (AJOL)

This paper presents a method for Reliability Analysis of wind energy embedded in power generation system for Indian scenario. This is done by evaluating the reliability index, loss of load expectation, for the power generation system with and without integration of wind energy sources in the overall electric power system.

Removing Barriers for Effective Deployment of Intermittent Renewable Generation

Science.gov (United States)

Arabali, Amirsaman

The stochastic nature of intermittent renewable resources is the main barrier to effective integration of renewable generation. This problem can be studied from feeder-scale and grid-scale perspectives. Two new stochastic methods are proposed to meet the feeder-scale controllable load with a hybrid renewable generation (including wind and PV) and energy storage system. For the first method, an optimization problem is developed whose objective function is the cost of the hybrid system including the cost of renewable generation and storage subject to constraints on energy storage and shifted load. A smart-grid strategy is developed to shift the load and match the renewable energy generation and controllable load. Minimizing the cost function guarantees minimum PV and wind generation installation, as well as storage capacity selection for supplying the controllable load. A confidence coefficient is allocated to each stochastic constraint which shows to what degree the constraint is satisfied. In the second method, a stochastic framework is developed for optimal sizing and reliability analysis of a hybrid power system including renewable resources (PV and wind) and energy storage system. The hybrid power system is optimally sized to satisfy the controllable load with a specified reliability level. A load-shifting strategy is added to provide more flexibility for the system and decrease the installation cost. Load shifting strategies and their potential impacts on the hybrid system reliability/cost analysis are evaluated trough different scenarios. Using a compromise-solution method, the best compromise between the reliability and cost will be realized for the hybrid system. For the second problem, a grid-scale stochastic framework is developed to examine the storage application and its optimal placement for the social cost and transmission congestion relief of wind integration. Storage systems are optimally placed and adequately sized to minimize the sum of operation

Engineered CRISPR Systems for Next Generation Gene Therapies.

Science.gov (United States)

Pineda, Michael; Moghadam, Farzaneh; Ebrahimkhani, Mo R; Kiani, Samira

2017-09-15

An ideal in vivo gene therapy platform provides safe, reprogrammable, and precise strategies which modulate cell and tissue gene regulatory networks with a high temporal and spatial resolution. Clustered regularly interspaced short palindromic repeats (CRISPR), a bacterial adoptive immune system, and its CRISPR-associated protein 9 (Cas9), have gained attention for the ability to target and modify DNA sequences on demand with unprecedented flexibility and precision. The precision and programmability of Cas9 is derived from its complexation with a guide-RNA (gRNA) that is complementary to a desired genomic sequence. CRISPR systems open-up widespread applications including genetic disease modeling, functional screens, and synthetic gene regulation. The plausibility of in vivo genetic engineering using CRISPR has garnered significant traction as a next generation in vivo therapeutic. However, there are hurdles that need to be addressed before CRISPR-based strategies are fully implemented. Some key issues center on the controllability of the CRISPR platform, including minimizing genomic-off target effects and maximizing in vivo gene editing efficiency, in vivo cellular delivery, and spatial-temporal regulation. The modifiable components of CRISPR systems: Cas9 protein, gRNA, delivery platform, and the form of CRISPR system delivered (DNA, RNA, or ribonucleoprotein) have recently been engineered independently to design a better genome engineering toolbox. This review focuses on evaluating CRISPR potential as a next generation in vivo gene therapy platform and discusses bioengineering advancements that can address challenges associated with clinical translation of this emerging technology.

Isolated Power Generation System Using Permanent Magnet Synchronous Generator with Improved Power Quality

Science.gov (United States)

Arya, Sabha Raj; Patel, Ashish; Giri, Ashutosh

2018-03-01

This paper deals wind energy based power generation system using Permanent Magnet Synchronous Generator (PMSG). It is controlled using advanced enhanced phase-lock loop for power quality features using distribution static compensator to eliminate the harmonics and to provide KVAR compensation as well as load balancing. It also manages rated potential at the point of common interface under linear and non-linear loads. In order to have better efficiency and reliable operation of PMSG driven by wind turbine, it is necessary to analyze the governing equation of wind based turbine and PMSG under fixed and variable wind speed. For handling power quality problems, power electronics based shunt connected custom power device is used in three wire system. The simulations in MATLAB/Simulink environment have been carried out in order to demonstrate this model and control approach used for the power quality enhancement. The performance results show the adequate performance of PMSG based power generation system and control algorithm.

System considerations for airborne, high power superconducting generators

International Nuclear Information System (INIS)

Southall, H.L.; Oberly, C.E.

1979-01-01

The design of rotating superconducting field windings in high power generators is greatly influenced by system considerations. Experience with two superconducting generators designed to produce 5 and 20 Mw resulted in a number of design restrictions. The design restrictions imposed by system considerations have not prevented low weight and high voltage power generation capability. The application of multifilament Nb;sub 3;Sn has permitted a large thermal margin to be designed into the rotating field winding. This margin permits the field winding to remain superconducting under severe system operational requirements. System considerations include: fast rotational startup, fast ramped magnetic fields, load induced transient fields and airborne cryogen logistics. Preliminary selection of a multifilament Nb;sub 3;Sn cable has resulted from these considerations. The cable will carry 864 amp at 8.5K and 6.8 Tesla. 10 refs

Draining down of a nuclear steam generating system

International Nuclear Information System (INIS)

Jawor, J.C.

1987-01-01

The method is described of draining down contained reactor-coolant water from the inverted vertical U-tubes of a vertical-type steam generator in which the upper, inverted U-shaped ends of the tubes are closed and the lower ends thereof are open. The steam generator is part of a nuclear powered steam generating system wherein the reactor coolant water is normally circulated from and back into the reactor via a loop comprising the steam generator and inlet and outlet conduits connected to the lower end of the steam generator. The method comprises continuously introducing a gas which is inert to the system and which is under pressure above atmospheric pressure into at least one of the downwardly facing open ends of each of the U-tubes from below the tube sheet in which the open ends of the U-tubes are mounted adjacent the lower end of the steam generator, while permitting the water to flow out from the open ends of the U-tubes

Method to calculating an internal electromagnetic pulse generated in a system under gamma radiation effect; Metod rascheta vnutrennego ehlektromagnitnogo impul`sa, generiruemogo v sisteme pri vozdejstvii gamma-izlucheniya

Energy Technology Data Exchange (ETDEWEB)

Ogorodnikov, S N

1994-12-31

A method of calculating internal electromagnetic pulse, generated in the system under effect of gamma radiation is developed. Ratios for basic electron flux characteristics and components of electric and magnetic fields generated by gamma radiation, are indicated for a cylindrical cavity under gamma radiation effect on its surface. To illustrate this a case is considered when a single flux velocity component is present.

Grid Monitoring and Advanced Control of Distributed Power Generation Systems

DEFF Research Database (Denmark)

Timbus, Adrian Vasile

. As an example, the latest published grid codes stress the ability of distributed generators, especially wind turbines, to stay connected during short grid disturbances and in addition to provide active/reactive power control at the point of common coupling. Based on the above facts, the need for improving...... reported in some countries creating concerns about power system stability. This leads to a continuous evolution of grid interconnection requirements towards a better controllability of generated power and an enhanced contribution of distributed power generation systems to power system stability...... and adding more features to the control of distributed power generation systems (DPGS) arises. As a consequence, this thesis focuses on grid monitoring methods and possible approaches in control in order to obtain a more reliable and  exible power generation system during normal and faulty grid conditions...

Effect of outer wing separation on lift and thrust generation in a flapping wing system

International Nuclear Information System (INIS)

Mahardika, Nanang; Viet, Nguyen Quoc; Park, Hoon Cheol

2011-01-01

We explore the implementation of wing feather separation and lead-lagging motion to a flapping wing. A biomimetic flapping wing system with separated outer wings is designed and demonstrated. The artificial wing feather separation is implemented in the biomimetic wing by dividing the wing into inner and outer wings. The features of flapping, lead-lagging, and outer wing separation of the flapping wing system are captured by a high-speed camera for evaluation. The performance of the flapping wing system with separated outer wings is compared to that of a flapping wing system with closed outer wings in terms of forward force and downward force production. For a low flapping frequency ranging from 2.47 to 3.90 Hz, the proposed biomimetic flapping wing system shows a higher thrust and lift generation capability as demonstrated by a series of experiments. For 1.6 V application (lower frequency operation), the flapping wing system with separated wings could generate about 56% higher forward force and about 61% less downward force compared to that with closed wings, which is enough to demonstrate larger thrust and lift production capability of the separated outer wings. The experiments show that the outer parts of the separated wings are able to deform, resulting in a smaller amount of drag production during the upstroke, while still producing relatively greater lift and thrust during the downstroke.

Model oriented application generation for industrial control systems

International Nuclear Information System (INIS)

Copy, B.; Barillere, R.; Blanco, E.; Fernandez Adiego, B.; Nogueira Fernandes, R.; Prieto Barreiro, I.

2012-01-01

The CERN Unified Industrial Control Systems framework (UNICOS) is a software generation methodology and a collection of development tools that standardizes the design of industrial control applications. A Software Factory, named the UNICOS Application Builder (UAB), was introduced to ease extensibility and maintenance of the framework, introducing a stable meta-model, a set of platform-independent models and platform-specific configurations against which code generation plug-ins and configuration generation plug-ins can be written. Such plug-ins currently target PLC programming environments (Schneider and SIEMENS PLCs) as well as SIEMENS WinCC Open Architecture SCADA (previously known as ETM PVSS) but are being expanded to cover more and more aspects of process control systems. We present what constitutes the UNICOS meta-model and the models in use, how these models can be used to capture knowledge about industrial control systems and how this knowledge can be used to generate both code and configuration for a variety of target usages. (authors)

Electric micro-generation system for nautical applications

International Nuclear Information System (INIS)

Giordana, A; Ponzinibbio, P

2005-01-01

Application specific requirements are studied in first part of this work.As well possible wind turbines and the switched reluctance generator choice fundaments are analyzed.In a second part, a Savonius helical turbine, switched reluctance generator and control system designs are reviewed. Finally, prototype test results are presented

Dynamic Braking System of a Tidal Generator: Preprint

Energy Technology Data Exchange (ETDEWEB)

Muljadi, Eduard; Wright, Alan; Gevorgian, Vahan; Donegan, James; Marnagh, Cian; McEntee, Jarlath

2016-08-01

Renewable energy generation has experienced significant cost reductions during the past decades, and it has become more accepted by the global population. In the beginning, wind generation dominated the development and deployment of renewable energy; however, during recent decades, photovoltaic (PV) generation has grown at a very significant pace due to the tremendous decrease in the cost of PV modules. The focus on renewable energy generation has now expanded to include new types with promising future applications, such as river and tidal generation. The input water flow to these types of resources is more predictable than wind or solar generation. The data used in this paper is representative of a typical river or tidal generator. The analysis is based on a generator with a power rating of 40 kW. The tidal generator under consideration is driven by two sets of helical turbines connected to each side of the generator located in between the turbines. The generator is operated in variable speed, and it is controlled to maximize the energy harvested as well as the operation of the turbine generator. The electrical system consists of a three-phase permanent magnet generator connected to a three-phase passive rectifier. The output of the rectifier is connected to a DC-DC converter to match the rectifier output to the DC bus voltage of the DC-AC inverter. The three-phase inverter is connected to the grid, and it is controlled to provide a good interface with the grid. One important aspect of river and tidal generation is the braking mechanism. In a tidal generator, the braking mechanism is important to avoid a runaway condition in case the connection to the grid is lost when there is a fault in the lines. A runaway condition may lead to an overspeed condition and cause extreme stresses on the turbine blade structure and eventual disintegration of the mechanical structure. In this paper, the concept of the dynamic braking system is developed and investigated for normal

Prediction of power system frequency response after generator outages using neural nets

Energy Technology Data Exchange (ETDEWEB)

Djukanovic, M B; Popovic, D P [Electrotechnicki Inst. ' Nikola Tesla' , Belgrade (Yugoslavia); Sobajic, D J; Pao, Y -H [Case Western Reserve Univ., Cleveland, OH (United States)

1993-09-01

A new methodology is presented for estimating the frequency behaviour of power systems necessary for an indication of under-frequency load shedding in steady-state security assessment. It is well known that large structural disturbances such as generator tripping or load outages can initiate cascading outages, system separation into islands, and even the complete breakup. The approach provides a fairly accurate method of estimating the system average frequency response without making simplifications or neglecting non-linearities and small time constants in the equations of generating units, voltage regulators and turbines. The efficiency of the new procedure is demonstrated using the New England power system model for a series of characteristic perturbations. The validity of the proposed approach is verified by comparison with the simulation of short-term dynamics including effects of control and automatic devices. (author)

Study on closed cycle MHD generation systems; Closed cycle MHD hatsuden system no kento

Energy Technology Data Exchange (ETDEWEB)

NONE

1988-03-01

The closed cycle noble gas MHD generation systems are surveyed and studied. The concept of closed cycle noble gas MHD generation is confirmed to extract high enthalpy, and now going into the engineering demonstration stage from the basic research stage. These systems have various characteristics. The highest working temperature is around 1,700 degrees C, which is close to that associated with the existing techniques. Use of helium or argon gas as the working fluid makes the system relatively free of various problems, e.g., corrosion. It can attain a much higher efficiency than the combined cycle involving gas turbine. It suffers less heat loss in the passages, is suitable for small- to medium-capacity power generation systems, and copes with varying load. The compact power generation passages decrease required size of the superconducting magnet. The technical problems to be solved include optimization of power generation conditions, demonstration of durability of the power generation passages, injection/recovery of the seed material, treatment of the working gas to remove molecular impurities, and development of heat exchangers serviceable at high temperature produced by direct combustion of coal. The conceptual designs of the triple combined system are completed. (NEDO)

Chaotic Music Generation System Using Music Conductor Gesture

OpenAIRE

Chen, Shuai; Maeda, Yoichiro; Takahashi, Yasutake

2013-01-01

In the research of interactive music generation, we propose a music generation method, that the computer generates the music, under the recognition of human music conductor's gestures.In this research, the generated music is tuned by the recognized gestures for the parameters of the network of chaotic elements in real time. The music conductor's hand motions are detected by Microsoft Kinect in this system. Music theories are embedded in the algorithm, as a result, the generated music will be ...

Music Conductor Gesture Recognized Interactive Music Generation System

OpenAIRE

CHEN, Shuai; MAEDA, Yoichiro; TAKAHASHI, Yasutake

2012-01-01

In the research of interactive music generation, we propose a music generation method, that the computer generates the music automatically, and then the music will be arranged under the human music conductor's gestures, before it outputs to us. In this research, the generated music is processed from chaotic sound, which is generated from the network of chaotic elements in realtime. The music conductor's hand motions are detected by Microsoft Kinect in this system. Music theories are embedded ...

Constrained approximation of effective generators for multiscale stochastic reaction networks and application to conditioned path sampling

Energy Technology Data Exchange (ETDEWEB)

Cotter, Simon L., E-mail: simon.cotter@manchester.ac.uk

2016-10-15

Efficient analysis and simulation of multiscale stochastic systems of chemical kinetics is an ongoing area for research, and is the source of many theoretical and computational challenges. In this paper, we present a significant improvement to the constrained approach, which is a method for computing effective dynamics of slowly changing quantities in these systems, but which does not rely on the quasi-steady-state assumption (QSSA). The QSSA can cause errors in the estimation of effective dynamics for systems where the difference in timescales between the “fast” and “slow” variables is not so pronounced. This new application of the constrained approach allows us to compute the effective generator of the slow variables, without the need for expensive stochastic simulations. This is achieved by finding the null space of the generator of the constrained system. For complex systems where this is not possible, or where the constrained subsystem is itself multiscale, the constrained approach can then be applied iteratively. This results in breaking the problem down into finding the solutions to many small eigenvalue problems, which can be efficiently solved using standard methods. Since this methodology does not rely on the quasi steady-state assumption, the effective dynamics that are approximated are highly accurate, and in the case of systems with only monomolecular reactions, are exact. We will demonstrate this with some numerics, and also use the effective generators to sample paths of the slow variables which are conditioned on their endpoints, a task which would be computationally intractable for the generator of the full system.

The effects of system configuration and operating condition on the MCFC system efficiency

Energy Technology Data Exchange (ETDEWEB)

Kang, B.S. [Korea Electric Power Research Institute, Taejeon (Korea)

2001-07-01

The process simulation model of an externally reformed molten carbonate fuel cell (MCFC) system is used to analyze quantitatively the parametric effect on the system efficiency. In order to verify the MCFC process simulation model, the 25-kW system was analyzed on the basis of the experimental data and its calculated efficiency showed reasonable. The overall system efficiency of high-temperature fuel cell system, especially MCFC, can not be increased without the proper thermal integration between heat recovery units and additional power generation from auxiliary power generating units such as turbines. The simulation results show that the configuration of unit operators in a given system has great effect on the system efficiency while the system size and operating condition have slightly lower effect on it. Based on the system configuration, optimal operating condition including fuel, oxidant utilization, and recycle ratio can be specified to maximize the system efficiency. (author). 12 refs., 10 figs., 2 tabs.

Appropriate heat load ratio of generator for different types of air cooled lithium bromide–water double effect absorption chiller

International Nuclear Information System (INIS)

Li, Zeyu; Liu, Jinping

2015-01-01

Highlights: • Effect of heat load ratio of generator on the performance was analyzed. • The performance is sensitive to heat load ratio of generator. • The appropriate heat load ratio of generator for four systems was obtained. • The change of appropriate heat load ratio of generator for four systems was studied. - Abstract: The lower coefficient of performance and higher risk of crystallization in the higher surrounding temperature is the primary disadvantage of air cooled lithium bromide–water double effect absorption chiller. Since the coefficient of performance and risk of crystallization strongly depend on the heat load ratio of generator, the appropriate heat load ratio of generator can improve the performance as the surrounding temperature is higher. The paper mainly deals with the appropriate heat load ratio of generator of air cooled lithium bromide–water double effect absorption chiller. Four type systems named series, pre-parallel, rear parallel and reverse parallel flow configuration were considered. The corresponding parametric model was developed to analyze the comprehensive effect of heat load ratio of generator on the coefficient of performance and risk of crystallization. It was found that the coefficient of performance goes up linearly with the decrease of heat load ratio of generator. Simultaneously, the risk of crystallization also rises slowly at first but increases fast finally. Consequently, the appropriate heat load ratio of generator for the series and pre-parallel flow type systems is suggested to be 0.02 greater than the minimum heat load ratio of generator and that for the rear parallel and reverse parallel flow chillers should be 0.01 higher than the minimum heat load ratio of generator. Besides, the changes of minimum heat load ratio of generator for different type systems with the working condition were analyzed and compared. It was found that the minimum heat load ratio of generator goes up with the increase of

Nonlinear decentralized robust governor control for hydroturbine-generator sets in multi-machine power systems

Energy Technology Data Exchange (ETDEWEB)

Qiang Lu; Yusong Sun; Yuanzhang Sun [Tsinghua University, Beijing (China). Dept. of Electrical Engineering; Felix F Wu; Yixin Ni [University of Hong Kong (China). Dept. of Electrical and Electronic Engineering; Yokoyama, Akihiko [University of Tokyo (Japan). Dept. of Electrical Engineering; Goto, Masuo; Konishi, Hiroo [Hitachi Ltd., Tokyo (Japan). Power System Div.

2004-06-01

A novel nonlinear decentralized robust governor control for hydroturbine-generator sets in multi-machine power systems is suggested in this paper. The nonelastic water hammer effect and disturbances are considered in the modeling. The advanced differential geometry theory, nonlinear robust control theory and the dynamic feedback method are combined to solve the problem. The nonlinear decentralized robust control law for the speed governor of hydroturbine-generators has been derived. The input signals to the proposed controller are all local measurements and independent to the system parameters. The derived control law guarantees the integrated system stability with disturbance attenuation, which is significant to the real power system application. Computer tests on an 8-machine, 36-bus power system show clearly the effectiveness of the new control strategy in transient stability enhancement and disturbance attenuation. The computer test results based on the suggested controller are compared favorably with those based on the conventional linear governor control. (author)

Port-Hamiltonian approaches to motion generation for mechanical systems

NARCIS (Netherlands)

Sakai, Satoru; Stramigioli, Stefano

This paper gives new motion generation methods for mechanical port-Hamiltonian systems. First, we propose a generation method based on an asymptotic stabilization method without damping assignment. This asymptotic stabilization method preserves the Hamiltonian structure in the closed-loop system

Synchronous generator wind energy conversion control system

Energy Technology Data Exchange (ETDEWEB)

Medeiros, A.L.R. [Wind Energy Group, Recife (Brazil); Lima, A.M.N.; Jacobina, C.B.; Simoes, F.J. [DEE, Campina Grande (Brazil)

1996-12-31

This paper presents the performance evaluation and the design of the control system of a WECS (Wind Energy Conversion System) that employs a synchronous generator based on its digital simulation. The WECS discussed in this paper is connected to the utility grid through two Pulse Width Modulated (PWM) power converters. The structure of the proposed WECS enables us to achieve high performance energy conversion by: (i) maximizing the wind energy capture and (ii) minimizing the reactive power flowing between the grid and the synchronous generator. 8 refs., 19 figs.

Stirling based micro co-generation system for single households

Energy Technology Data Exchange (ETDEWEB)

Ribberink, J.S.; Zutt, J.G.M.; Rabou, L.P.L.M.; Beckers, G.J.J. [ECN Clean Fossil Fuels, Petten (Netherlands); Baijens, C.A.W.; Luttikholt, J.J.M. [ATAG Verwarming, Lichtenvoorde (Netherlands)

2000-04-01

This paper describes the progress made in the ENATEC development program for a free piston Stirling engine based micro co-generation system that serves the supply of up to 1 kW{sub e} and up to 24 kW heat for domestic heating and/or for hot tap water production for single households at overall system efficiencies of 96%. Experiments show that the free piston Stirling engines from Stirling Technology Company run very reliably and controllably, and that the efficiency targets for the 1 kW{sub e} micro co-generation system are feasible. A ceramic foam burner with good heat transfer characteristics and low NOx emissions was developed. A demonstration micro co-generation unit was built and successfully presented. A 1 kW{sub e} free piston Stirling engine for the European market was developed. High efficiencies at full load and at part load, low emissions, low noise, and minimum maintenance make the Stirling engine based micro co-generation system an attractive candidate for the next generation of domestic boilers in Europe. 5 refs.

Control system for fluid heated steam generator

Science.gov (United States)

Boland, J.F.; Koenig, J.F.

1984-05-29

A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

A Low-cost System for Generating Near-realistic Virtual Actors

Science.gov (United States)

Afifi, Mahmoud; Hussain, Khaled F.; Ibrahim, Hosny M.; Omar, Nagwa M.

2015-06-01

Generating virtual actors is one of the most challenging fields in computer graphics. The reconstruction of a realistic virtual actor has been paid attention by the academic research and the film industry to generate human-like virtual actors. Many movies were acted by human-like virtual actors, where the audience cannot distinguish between real and virtual actors. The synthesis of realistic virtual actors is considered a complex process. Many techniques are used to generate a realistic virtual actor; however they usually require expensive hardware equipment. In this paper, a low-cost system that generates near-realistic virtual actors is presented. The facial features of the real actor are blended with a virtual head that is attached to the actor's body. Comparing with other techniques that generate virtual actors, the proposed system is considered a low-cost system that requires only one camera that records the scene without using any expensive hardware equipment. The results of our system show that the system generates good near-realistic virtual actors that can be used on many applications.

Reloadable radioactive generator system

International Nuclear Information System (INIS)

Colombetti, L.G.

1977-01-01

A generator system that can be reloaded with an elutable radioactive material, such as 99 molybdenum, a multiple number of times is described. The system basically comprises a column filled with alumina, a loading vial containing a predetermined amount of the elutable radioactive material, and a rinsing vial containing a sterile solution. The two vials are connected by a conduit so that when communication is achieved between the column and loading vial and an evacuated vial is placed in communication with the bottom of the column, the predetermined amount of the radioactive material in the loading vial will be transferred to the column. The procedure can be repeated as the elutable material in the column is dissipated

Decentralized electricity generation by using photovoltaic grid-connected solar system

International Nuclear Information System (INIS)

Tyutyundziev, N.; Vitanov, P.; Radkov, R.; Grottke, M.

2006-01-01

AcadPV is the first demonstration installation connected permanently to LV grid in Sofia, Bulgaria aiming at assessment of PV efficiencies and cost-effectiveness. A thorough analysis has been carried out in order to select PV system site, supporting construction design and orientation. The PV generator is divided to 3 PV subfields equipped by 3 SUNPOWER inverters connected to 3 separated phases of the grid. The performance of 10kWp PV system has been evaluated during the first year of operation and compared to PV simulation software results

Next Generation Space Surveillance System-of-Systems

Science.gov (United States)

McShane, B.

2014-09-01

International economic and military dependence on space assets is pervasive and ever-growing in an environment that is now congested, contested, and competitive. There are a number of natural and man-made risks that need to be monitored and characterized to protect and preserve the space environment and the assets within it. Unfortunately, today's space surveillance network (SSN) has gaps in coverage, is not resilient, and has a growing number of objects that get lost. Risks can be efficiently and effectively mitigated, gaps closed, resiliency improved, and performance increased within a next generation space surveillance network implemented as a system-of-systems with modern information architectures and analytic techniques. This also includes consideration for the newest SSN sensors (e.g. Space Fence) which are born Net-Centric out-of-the-box and able to seamlessly interface with the JSpOC Mission System, global information grid, and future unanticipated users. Significant opportunity exists to integrate legacy, traditional, and non-traditional sensors into a larger space system-of-systems (including command and control centers) for multiple clients through low cost sustainment, modification, and modernization efforts. Clients include operations centers (e.g. JSpOC, USSTRATCOM, CANSPOC), Intelligence centers (e.g. NASIC), space surveillance sensor sites (e.g. AMOS, GEODSS), international governments (e.g. Germany, UK), space agencies (e.g. NASA), and academic institutions. Each has differing priorities, networks, data needs, timeliness, security, accuracy requirements and formats. Enabling processes and technologies include: Standardized and type accredited methods for secure connections to multiple networks, machine-to-machine interfaces for near real-time data sharing and tip-and-queue activities, common data models for analytical processing across multiple radar and optical sensor types, an efficient way to automatically translate between differing client and

Research on Distributed PV Storage Virtual Synchronous Generator System and Its Static Frequency Characteristic Analysis

Directory of Open Access Journals (Sweden)

Xiangwu Yan

2018-03-01

Full Text Available The increasing penetration rate of grid connected renewable energy power generation reduces the primary frequency regulation capability of the system and poses a challenge to the security and stability of the power grid. In this paper, a distributed photovoltaic (PV storage virtual synchronous generator system is constructed, which realizes the external characteristics of synchronous generator/motor. For this kind of input/output bidirectional devices (e.g., renewable power generation/storage combined systems, pumped storage power stations, battery energy storage systems, and vehicle-to-grid electric vehicles, a synthesis analysis method for system power-frequency considering source-load static frequency characteristics (S-L analysis method is proposed in order to depict the system’s power balance dynamic adjustment process visually. Simultaneously, an inertia matching method is proposed to solve the problem of inertia matching in the power grid. Through the simulation experiment in MATLAB, the feasibility of the distributed PV storage synchronous virtual machine system is verified as well as the effectiveness of S-L analysis method and inertia matching method.

The effect of numerical techniques on differential equation based chaotic generators

KAUST Repository

Zidan, Mohammed A.; Radwan, Ahmed G.; Salama, Khaled N.

2012-01-01

In this paper, we study the effect of the numerical solution accuracy on the digital implementation of differential chaos generators. Four systems are built on a Xilinx Virtex 4 FPGA using Euler, mid-point, and Runge-Kutta fourth order techniques

Market protocols in ERCOT and their effect on wind generation

International Nuclear Information System (INIS)

Sioshansi, Ramteen; Hurlbut, David

2010-01-01

Integrating wind generation into power systems and wholesale electricity markets presents unique challenges due to the characteristics of wind power, including its limited dispatchability, variability in generation, difficulty in forecasting resource availability, and the geographic location of wind resources. Texas has had to deal with many of these issues beginning in 2002 when it restructured its electricity industry and introduced aggressive renewable portfolio standards that helped spur major investments in wind generation. In this paper we discuss the issues that have arisen in designing market protocols that take account of these special characteristics of wind generation and survey the regulatory and market rules that have been developed in Texas. We discuss the perverse incentives some of the rules gave wind generators to overschedule generation in order to receive balancing energy payments, and steps that have been taken to mitigate those incentive effects. Finally, we discuss more recent steps taken by the market operator and regulators to ensure transmission capacity is available for new wind generators that are expected to come online in the future.

Rated power factor and excitation system of large turbine generator

International Nuclear Information System (INIS)

Tokumitsu, Iwao; Watanabe, Takashi; Banjou, Minoru.

1979-01-01

As for the rated power factor of turbine generators for thermal power stations, 90% has been adopted since around 1960. On the other hand, power transmission system has entered 500 kV age, and 1,000 kV transmission is expected in the near future. As for the supply of reactive power from thermal and nuclear turbine generators, the necessity of supplying leading reactive power has rather increased. Now, the operating power factor of thermal and nuclear generators becomes 96 to 100% actually. As for the excess stability of turbine generators owing to the strengthening of transmission system and the adoption of super-high voltage, the demand of strict conditions can be dealt with by the adoption of super-fast response excitation system of thyristor shunt winding self exciting type. The adoption of the turbine generators with 90 to 95% power factor and the adoption of the thyristor shunt winding self exciting system were examined and evaluated. The rated power factor of generators, excitation system and economy of adopting these systems are explained. When the power factor of generators is increased from 0.9 to 0.95, about 6% of saving can be obtained in the installation cost. When the thyristor shunt winding self excitation is adopted, it is about 10% more economical than AC excitation. (Kako, I.)

Future development of the electricity systems with distributed generation

Energy Technology Data Exchange (ETDEWEB)

Bayod-Rujula, Angel A. [Department of Electrical Engineering, Centro Politecnico Superior, University of Zaragoza, C/Maria de Luna, 3, 50018 Zaragoza (Spain)

2009-03-15

Electrical power systems have been traditionally designed taking energy from high-voltage levels, and distributing it to lower voltage level networks. There are large generation units connected to transmission networks. But in the future there will be a large number of small generators connected to the distribution networks. Efficient integration of this distributed generation requires network innovations. A development of active distribution network management, from centralised to more distributed system management, is needed. Information, communication, and control infrastructures will be needed with increasing complexity of system management. Some innovative concepts such as microgrids and virtual utilities will be presented. (author)

Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

Science.gov (United States)

Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

2011-01-01

With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.

Optimum distributed generation placement with voltage sag effect minimization

International Nuclear Information System (INIS)

Biswas, Soma; Goswami, Swapan Kumar; Chatterjee, Amitava

2012-01-01

Highlights: ► A new optimal distributed generation placement algorithm is proposed. ► Optimal number, sizes and locations of the DGs are determined. ► Technical factors like loss, voltage sag problem are minimized. ► The percentage savings are optimized. - Abstract: The present paper proposes a new formulation for the optimum distributed generator (DG) placement problem which considers a hybrid combination of technical factors, like minimization of the line loss, reduction in the voltage sag problem, etc., and economical factors, like installation and maintenance cost of the DGs. The new formulation proposed is inspired by the idea that the optimum placement of the DGs can help in reducing and mitigating voltage dips in low voltage distribution networks. The problem is configured as a multi-objective, constrained optimization problem, where the optimal number of DGs, along with their sizes and bus locations, are simultaneously obtained. This problem has been solved using genetic algorithm, a traditionally popular stochastic optimization algorithm. A few benchmark systems radial and networked (like 34-bus radial distribution system, 30 bus loop distribution system and IEEE 14 bus system) are considered as the case study where the effectiveness of the proposed algorithm is aptly demonstrated.

Report on demonstrative research on photovoltaic power generation system in Myanmar

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

With an objective of installation and demonstrative operation in Myanmar of a power generation system combining a small-scale photovoltaic power generation system, a wind power generation system, and a diesel generator, research and development is being made under a six year plan starting in 1999 and ending in 2004. Comparative discussions were given on the installation location of the power generation system for the climatic conditions in Chaungthar and Letkhokekone, whereas the final decision was given on Chaungthar. This project plans installation of a photovoltaic power generation system of 80 kW, a wind power generation system of 40 kW, and a diesel generator of 60 kW. Power generation will start at 6 o'clock in the morning and continue to 11 o'clock at night every day, with a storage battery of 1,000 Ah and a stabilized load comprising of ice maker units to be installed. Observation of wind power and solar insolation is being continued with an aim of acquiring data over a period of one year or longer, whereas the data as have been forecasted are being acquired at the present. The diesel generator was manufactured in Japan, which has been arrived at the port of Yangon in February 2001, and installed at the site in Chaungthar in March. (NEDO)

Experimental Study of a Thermoelectric Generation System

DEFF Research Database (Denmark)

Zhu, Junpeng; Gao, Junling; Chen, Min

2011-01-01

. System-level simulation is carried out using a quasi-one-dimensional numerical model that enables direct comparison with experimental results. The results of both experiment and simulation will provide a foundation to improve and optimize complex thermoelectric generation systems....

Development of an Optimal Power Control Scheme for Wave-Offshore Hybrid Generation Systems

Directory of Open Access Journals (Sweden)

Seungmin Jung

2015-08-01

Full Text Available Integration technology of various distribution systems for improving renewable energy utilization has been receiving attention in the power system industry. The wave-offshore hybrid generation system (HGS, which has a capacity of over 10 MW, was recently developed by adopting several voltage source converters (VSC, while a control method for adopted power conversion systems has not yet been configured in spite of the unique system characteristics of the designated structure. This paper deals with a reactive power assignment method for the developed hybrid system to improve the power transfer efficiency of the entire system. Through the development and application processes for an optimization algorithm utilizing the real-time active power profiles of each generator, a feasibility confirmation of power transmission loss reduction was implemented. To find the practical effect of the proposed control scheme, the real system information regarding the demonstration process was applied from case studies. Also, an evaluation for the loss of the improvement rate was calculated.

Windfarm Generation Assessment for ReliabilityAnalysis of Power Systems

DEFF Research Database (Denmark)

Negra, Nicola Barberis; Holmstrøm, Ole; Bak-Jensen, Birgitte

2007-01-01

Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...

Windfarm generation assessment for reliability analysis of power systems

DEFF Research Database (Denmark)

Negra, N.B.; Holmstrøm, O.; Bak-Jensen, B.

2007-01-01

Due to the fast development of wind generation in the past ten years, increasing interest has been paid to techniques for assessing different aspects of power systems with a large amount of installed wind generation. One of these aspects concerns power system reliability. Windfarm modelling plays...

An expert system for diesel generator diagnostics

International Nuclear Information System (INIS)

Bley, D.C.; Read, J.W.; Kaplan, S.; Liming, J.K.; Brosee, N.M.; Hanley, D.W.

1987-01-01

The idea of developing artificial intelligence (AI) systems to capture the knowledge of human experts is receiving much attention these days. The idea is even more attractive when important expertise resides within a single individual, especially one who is nearing retirement and who has not otherwise recorded or passed along his important knowledge and thought processes. The diesel generators at Pilgrim Nuclear Power Station have performed exceptionally well, primarily due to the care and attention of one man. Therefore, the authors are constructing an expert system for the diagnosis of diesel generator problems at Pilgrim. This paper includes a description of the expert system design and operation, examples from the knowledge base, and sample diagnoses, so the reader can observe the process in action

Optimization of disk generator performance for base-load power plant systems applications

International Nuclear Information System (INIS)

Teare, J.D.; Loubsky, W.J.; Lytle, J.K.; Louis, J.F.

1980-01-01

Disk generators for use in base-load MHD power plants are examined for both open-cycle and closed-cycle operating modes. The OCD cases are compared with PSPEC results for a linear channel; enthalpy extractions up to 23% with 71% isentropic efficiency are achievable with generator inlet conditions similar to those used in PSPEC, thus confirming that the disk configuration is a viable alternative for base-load power generation. The evaluation of closed-cycle disks includes use of a simplified cycle model. High system efficiencies over a wide range of power levels are obtained for effective Hall coefficients in the range 2.3 to 4.9. Cases with higher turbulence (implying β/sub eff/ less than or equal to 2.4) yield high system efficiencies at power levels of 100 to 500 MW/sub e/. All these CCD cases compare favorably with linear channels reported in the GE ECAS study, yielding higher isentropic efficiences for a given enthalpy extraction. Power densities in the range 70 to 170 MW/m 3 appear feasible, leading to very compact generator configurations

Photovoltaic-wind hybrid autonomous generation systems in Mongolia

Energy Technology Data Exchange (ETDEWEB)

Dei, Tsutomu; Ushiyama, Izumi

2005-01-01

Two hybrid stand-alone (autonomous) power systems, each with wind and PV generation, were studied as installed at health clinics in semi-desert and mountainous region in Mongolia. Meteorological and system operation parameters, including power output and the consumption of the system, were generally monitored by sophisticated monitoring. However, where wind and solar site information was lacking, justifiable estimates were made. The results show that there is a seasonal complementary relationship between wind and solar irradiation in Tarot Sum. The users understood the necessity of Demand Side Management of isolated wind-PV generation system through technology transfer seminars and actually executed DSM at both sites. (author)

Electrical power systems for distributed generation

Energy Technology Data Exchange (ETDEWEB)

Robertson, T.A.; Huval, S.J. [Stewart & Stevenson Services, Inc., Houston, TX (United States)

1996-12-31

{open_quotes}Distributed Generation{close_quotes} has become the {open_quotes}buzz{close_quotes} word of an electric utility industry facing deregulation. Many industrial facilities utilize equipment in distributed installations to serve the needs of a thermal host through the capture of exhaust energy in a heat recovery steam generator. The electrical power generated is then sold as a {open_quotes}side benefit{close_quotes} to the cost-effective supply of high quality thermal energy. Distributed generation is desirable for many different reasons, each with unique characteristics of the product. Many years of experience in the distributed generation market has helped Stewart & Stevenson to define a range of product features that are crucial to most any application. The following paper will highlight a few of these applications. The paper will also examine the range of products currently available and in development. Finally, we will survey the additional services offered by Stewart & Stevenson to meet the needs of a rapidly changing power generation industry.

Parasitic effects in superconducting quantum interference device-based radiation comb generators

Energy Technology Data Exchange (ETDEWEB)

Bosisio, R., E-mail: riccardo.bosisio@nano.cnr.it [SPIN-CNR, Via Dodecaneso 33, 16146 Genova (Italy); NEST, Instituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Giazotto, F., E-mail: giazotto@sns.it [NEST, Instituto Nanoscienze-CNR and Scuola Normale Superiore, I-56127 Pisa (Italy); Solinas, P., E-mail: paolo.solinas@spin.cnr.it [SPIN-CNR, Via Dodecaneso 33, 16146 Genova (Italy)

2015-12-07

We study several parasitic effects on the implementation of a Josephson radiation comb generator based on a dc superconducting quantum interference device (SQUID) driven by an external magnetic field. This system can be used as a radiation generator similarly to what is done in optics and metrology, and allows one to generate up to several hundreds of harmonics of the driving frequency. First we take into account how the assumption of a finite loop geometrical inductance and junction capacitance in each SQUID may alter the operation of the devices. Then, we estimate the effect of imperfections in the fabrication of an array of SQUIDs, which is an unavoidable source of errors in practical situations. We show that the role of the junction capacitance is, in general, negligible, whereas the geometrical inductance has a beneficial effect on the performance of the device. The errors on the areas and junction resistance asymmetries may deteriorate the performance, but their effect can be limited to a large extent by a suitable choice of fabrication parameters.

Next generation of energy production systems

International Nuclear Information System (INIS)

Rouault, J.; Garnier, J.C.; Carre, F.

2003-01-01

This document gathers the slides that have been presented at the Gedepeon conference. Gedepeon is a research group involving scientists from Cea (French atomic energy commission), CNRS (national center of scientific research), EDF (electricity of France) and Framatome that is devoted to the study of new energy sources and particularly to the study of the future generations of nuclear systems. The contributions have been classed into 9 topics: 1) gas cooled reactors, 2) molten salt reactors (MSBR), 3) the recycling of plutonium and americium, 4) reprocessing of molten salt reactor fuels, 5) behavior of graphite under radiation, 6) metallic materials for molten salt reactors, 7) refractory fuels of gas cooled reactors, 8) the nuclear cycle for the next generations of nuclear systems, and 9) organization of research programs on the new energy sources

Voltage Control System of A DC Generator Using PLC

OpenAIRE

Subrata CHATTOPADHYAY; Sagarika PAL

2008-01-01

The voltage control system of a DC generator may suffer from high frequency oscillations without offset or low frequency oscillation with offset. A PID controller can eliminate both these errors. In the present paper, the voltage control system of a DC generator using a PLC based PID controller has been designed. Operation of PLC as a continuous controller has been described and the load characteristic of DC generator with and without controller have been determined experimentally and reporte...

How will fourth-generation nuclear systems be deployed?; Comment les systemes nucleaires de 4. generation se deploieront-ils?

Energy Technology Data Exchange (ETDEWEB)

Bonin, B.; Carre, F. [CEA Saclay, Dir. de l' Energie Nucleaire, 91 - Gif sur Yvette (France)

2007-07-01

If it is to be fully consonant with a sustainable development perspective, nuclear energy needs must rely on systems that will ensure the greatest optimization of fissile material utilization, while minimizing production of ultimate waste. Deployment scenarios, for systems of the new generation, remain very much open. (authors)

FY 2000 report on the demonstrative research for photovoltaic power generation system in Thailand. Demonstrative study on photovoltaic power generation grid-connected system

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-09-01

In relation to the demonstrative study of the photovoltaic power system that is planned in Libong island, Thailand, the FY 2000 results were reported. In this R and D, construction/demonstrative operation were planned for a photovoltaic power station with a generation output of 100kW, photovoltaic power system in school facilities, and system for transmitting/distributing power to houses by connecting the power station and power system. In this fiscal year, the field survey was conducted together with the alteration from Yao Yai island, for which the demonstrative study was planned at first, to Libong island. The electric equipment was selected which met the requests from Thailand and the results of the field survey, and the basic design of the photovoltaic power generation/transmission/distribution system was completed. Based on this, the design/manufacture of photovoltaic power generation modules, power control equipment, measuring equipment, etc. were made. At the construction site of photovoltaic power station, construction work such as land formation was conducted. Further, Thai engineers who visited Japan did the following: discussions about power system, presence at test/inspection of photovoltaic power generation modules, visits to photovoltaic power stations, wind power stations, etc. (NEDO)

The effect of using sun tracking systems on the voltage-current characteristics and power generation of flat plate photovoltaics

International Nuclear Information System (INIS)

Abdallah, Salah

2004-01-01

An experimental study was performed to investigate the effect of using different types of sun tracking systems on the voltage-current characteristics and electrical power generation at the output of flat plate photovoltaics (FPPV). Four electromechanical sun tracking systems, two axes, one axis vertical, one axis east-west and one axis north-south, were designed and constructed for the purpose of investigating the effect of tracking on the electrical values, current, voltage and power, according to the different loads (variable resistance). The above mentioned variables were measured at the output of the FPPV and compared with those on a fixed surface. The results indicated that the volt-ampere characteristics on the tracking surfaces were significantly greater than that on a fixed surface. There were increases of electrical power gain up to 43.87%, 37.53%, 34.43% and 15.69% for the two axes, east-west, vertical and north-south tracking, respectively, as compared with the fixed surface inclined 32 deg. to the south in Amman, Jordan

Participation of superoxide generating system, superoxide dismutase and vitamin E in the radiation hazards

International Nuclear Information System (INIS)

Aono, Kaname; Yamamoto, Michio; Iida, Sosuke; Utsumi, Kozo

1978-01-01

In relation to the mechanism by which hemolysis was induced in radiated human erythrocytes in vitro, several inducements of membrane lipid peroxidation and protective effects of vitamin E (V.E) and superoxide dismutase (SOD) were investigated. (1) K + -release from erythrocytes was accelerated by radiation prior to hemolysis. These accelerated hemolysis and K + -release were protected remarkably by V.E and evidently by SOD. (2) Mitochondrial Fe 2+ induced and Fe 3+ -superoxide generating system -- ADP induced lipid peroxidation, and microsomal superoxide generating system -- induced lipid peroxidation were also protected by V.E and SOD. (3) Radiation of x-ray or 60 Co γ-ray accelerated lipid peroxidation of liver homogenate, microsome and liposome. Some of these accelerated lipid peroxidations were protected effectively by V.E and SOD. These results suggest that superoxide and/or OH generation by radiation induces of membrane lipid peroxidation, which leads deterioration of membrane resulting in the change of ion permeability and then hemolysis. (author)

Coherency Identification of Generators Using a PAM Algorithm for Dynamic Reduction of Power Systems

Directory of Open Access Journals (Sweden)

Seung-Il Moon

2012-11-01

Full Text Available This paper presents a new coherency identification method for dynamic reduction of a power system. To achieve dynamic reduction, coherency-based equivalence techniques divide generators into groups according to coherency, and then aggregate them. In order to minimize the changes in the dynamic response of the reduced equivalent system, coherency identification of the generators should be clearly defined. The objective of the proposed coherency identification method is to determine the optimal coherent groups of generators with respect to the dynamic response, using the Partitioning Around Medoids (PAM algorithm. For this purpose, the coherency between generators is first evaluated from the dynamic simulation time response, and in the proposed method this result is then used to define a dissimilarity index. Based on the PAM algorithm, the coherent generator groups are then determined so that the sum of the index in each group is minimized. This approach ensures that the dynamic characteristics of the original system are preserved, by providing the optimized coherency identification. To validate the effectiveness of the technique, simulated cases with an IEEE 39-bus test system are evaluated using PSS/E. The proposed method is compared with an existing coherency identification method, which uses the K-means algorithm, and is found to provide a better estimate of the original system. 

Mathematical modeling of control system for the experimental steam generator

Science.gov (United States)

Podlasek, Szymon; Lalik, Krzysztof; Filipowicz, Mariusz; Sornek, Krzysztof; Kupski, Robert; Raś, Anita

2016-03-01

A steam generator is an essential unit of each cogeneration system using steam machines. Currently one of the cheapest ways of the steam generation can be application of old steam generators came from army surplus store. They have relatively simple construction and in case of not so exploited units - quite good general conditions, and functionality of mechanical components. By contrast, electrical components and control systems (mostly based on relay automatics) are definitely obsolete. It is not possible to use such units with cooperation of steam bus or with steam engines. In particular, there is no possibility for automatically adjustment of the pressure and the temperature of the generated steam supplying steam engines. Such adjustment is necessary in case of variation of a generator load. The paper is devoted to description of improvement of an exemplary unit together with construction of the measurement-control system based on a PLC. The aim was to enable for communication between the steam generator and controllers of the steam bus and steam engines in order to construction of a complete, fully autonomic and maintenance-free microcogeneration system.

Development of a framework for the neutorinics analysis system for next generation (2) (Contract research)

International Nuclear Information System (INIS)

Hirai, Yasushi; Hyoudou, Hideaki; Tatsumi, Masahiro; Jin, Tomoyuki; Yokoyama, Kenji

2008-10-01

Japan Atomic Energy Agency promotes development of innovative analysis methods and models in fundamental studies for next-generation nuclear reactor systems. In order to efficiently and effectively reflect the latest analysis methods and models to primary design of prototype reactor and/or in-core fuel management for power reactors, a next-generation analysis system MARBLE has been developed. The next-generation system provides solutions to the following requirements: (1) Flexibility, extensibility and user-friendliness that can apply new methods and models rapidly and effectively for fundamental studies, (2) quantitative assurance of solution accuracy and adaptive scoping range for design studies, (3) coupling analysis among different study domains for the purpose of rationalization of plant systems and improvement of reliability, (4) maintainability and reusability for system extensions for the purpose of total quality assurance and development efficiency. There has been a problem of extreme inefficiency due to lack of functionality in the conventional analysis system when changing analysis targets and/or modeling levels. In order to solve this problem, a policy of the hybrid system is adopted for the next-generation system, in which a controlling part is implemented in the scripting language with rich flexibility and maintainability and solution kernels that requires execution speed in the system language. In this study, detailed design of a framework, its implementation and tests are conducted so that a Python system layer can drive calculation codes written in C++ and/or Fortran. It is confirmed that various type of calculation codes such as diffusion, transport and burnup codes can be treated in the same manner on the platform for unified management system for calculation codes with a data exchange mechanism for abstracted data model between the Python and the calculation code layers. (author)

Application of Airborne LiDAR Data and Geographic Information Systems (GIS to Develop a Distributed Generation System for the Town of Normal, IL

Directory of Open Access Journals (Sweden)

Jin H. Jo

2015-03-01

Full Text Available Distributed generation allows a variety of small, modular power-generating technologies to be combined with load management and energy storage systems to improve the quality and reliability of our electricity supply. As part of the US Environmental Protection Agency's effort to reduce CO2 emissions from existing power plants by 30% by 2030, distributed generation through solar photovoltaic systems provides a viable option for mitigating the negative impacts of centralized fossil fuel plants. This study conducted a detailed analysis to identify the rooftops in a town in Central Illinois that are suitable for distributed generation solar photovoltaic systems with airborn LiDAR data and to quantify their energy generation potential with an energy performance model. By utilizing the available roof space of the 9,718 buildings in the case study area, a total of 39.27 MW solar photovoltaic systems can provide electrical generation of 53,061 MWh annually. The unique methodology utilized for this assessment of a town's solar potential provides an effective way to invest in a more sustainable energy future and ensure economic stability.

Study of thermoelectric systems applied to electric power generation

International Nuclear Information System (INIS)

Rodriguez, A.; Vian, J.G.; Astrain, D.; Martinez, A.

2009-01-01

A computational model has been developed in order to simulate the thermal and electric behavior of thermoelectric generators. This model solves the nonlinear system of equations of the thermoelectric and heat transfer equations. The inputs of the program are the thermoelectric parameters as a function of temperature and the boundary conditions, (room temperature and residual heat flux). The outputs are the temperature values of all the elements forming the thermoelectric generator, (performance, electric power, voltage and electric current generated). The model solves the equation system using the finite difference method and semi-empirical expressions for the convection coefficients. A thermoelectric electric power generation test bench has been built in order to validate and determine the accuracy of the computational model, which maximum error is lower than 5%. The objective of this study is to create a design tool that allows us to solve the system of equations involved in the electric generation process without needing to impose boundary conditions that are not known in the design phase, such as the temperature of the Peltier modules. With the computational model, we study the influence of the heat flux supplied as well as the room temperature on the electric power generated.

Nonlinear spin current generation in noncentrosymmetric spin-orbit coupled systems

Science.gov (United States)

Hamamoto, Keita; Ezawa, Motohiko; Kim, Kun Woo; Morimoto, Takahiro; Nagaosa, Naoto

2017-06-01

Spin current plays a central role in spintronics. In particular, finding more efficient ways to generate spin current has been an important issue and has been studied actively. For example, representative methods of spin-current generation include spin-polarized current injections from ferromagnetic metals, the spin Hall effect, and the spin battery. Here, we theoretically propose a mechanism of spin-current generation based on nonlinear phenomena. By using Boltzmann transport theory, we show that a simple application of the electric field E induces spin current proportional to E2 in noncentrosymmetric spin-orbit coupled systems. We demonstrate that the nonlinear spin current of the proposed mechanism is supported in the surface state of three-dimensional topological insulators and two-dimensional semiconductors with the Rashba and/or Dresselhaus interaction. In the latter case, the angular dependence of the nonlinear spin current can be manipulated by the direction of the electric field and by the ratio of the Rashba and Dresselhaus interactions. We find that the magnitude of the spin current largely exceeds those in the previous methods for a reasonable magnitude of the electric field. Furthermore, we show that application of ac electric fields (e.g., terahertz light) leads to the rectifying effect of the spin current, where dc spin current is generated. These findings will pave a route to manipulate the spin current in noncentrosymmetric crystals.

Predictive control of a chaotic permanent magnet synchronous generator in a wind turbine system

International Nuclear Information System (INIS)

Messadi, Manal; Mellit, Adel; Kemih, Karim; Ghanes, Malek

2015-01-01

This paper investigates how to address the chaos problem in a permanent magnet synchronous generator (PMSG) in a wind turbine system. Predictive control approach is proposed to suppress chaotic behavior and make operating stable; the advantage of this method is that it can only be applied to one state of the wind turbine system. The use of the genetic algorithms to estimate the optimal parameter values of the wind turbine leads to maximization of the power generation. Moreover, some simulation results are included to visualize the effectiveness and robustness of the proposed method. (paper)

Third-generation imaging sensor system concepts

Science.gov (United States)

Reago, Donald A.; Horn, Stuart B.; Campbell, James, Jr.; Vollmerhausen, Richard H.

1999-07-01

Second generation forward looking infrared sensors, based on either parallel scanning, long wave (8 - 12 um) time delay and integration HgCdTe detectors or mid wave (3 - 5 um), medium format staring (640 X 480 pixels) InSb detectors, are being fielded. The science and technology community is now turning its attention toward the definition of a future third generation of FLIR sensors, based on emerging research and development efforts. Modeled third generation sensor performance demonstrates a significant improvement in performance over second generation, resulting in enhanced lethality and survivability on the future battlefield. In this paper we present the current thinking on what third generation sensors systems will be and the resulting requirements for third generation focal plane array detectors. Three classes of sensors have been identified. The high performance sensor will contain a megapixel or larger array with at least two colors. Higher operating temperatures will also be the goal here so that power and weight can be reduced. A high performance uncooled sensor is also envisioned that will perform somewhere between first and second generation cooled detectors, but at significantly lower cost, weight, and power. The final third generation sensor is a very low cost micro sensor. This sensor can open up a whole new IR market because of its small size, weight, and cost. Future unattended throwaway sensors, micro UAVs, and helmet mounted IR cameras will be the result of this new class.

LRSYS, PASCAL LR(1) Parser Generator System

International Nuclear Information System (INIS)

O'Hair, K.

1991-01-01

Description of program or function: LRSYS is a complete LR(1) parser generator system written entirely in a portable subset of Pascal. The system, LRSYS, includes a grammar analyzer program (LR) which reads a context-free (BNF) grammar as input and produces LR(1) parsing tables as output, a lexical analyzer generator (LEX) which reads regular expressions created by the REG process as input and produces lexical tables as output, and various parser skeletons that get merged with the tables to produce complete parsers (SMAKE). Current parser skeletons include Pascal, FORTRAN 77, and C. In addition, the CRAY1, DEC VAX11 version contains LRLTRAN and CFT- FORTRAN 77 skeletons. Other language skeletons can easily be added to the system. LRSYS is based on the LR program (NESC Abstract 822)

Integration of stochastic generation in power systems

NARCIS (Netherlands)

Papaefthymiou, G.; Schavemaker, P.H.; Sluis, van der L.; Kling, W.L.; Kurowicka, D.; Cooke, R.M.

2006-01-01

Stochastic generation, i.e., electrical power production by an uncontrolled primary energy source, is expected to play an important role in future power systems. A new power system structure is created due to the large-scale implementation of this small-scale, distributed, non-dispatchable

The development of new radionuclide generator systems for nuclear medicine applications

International Nuclear Information System (INIS)

Knapp, F.F. Jr.; Callahan, A.P.; Mirzadeh, S.; Brihaye, C.; Guillaume, M.

1991-01-01

Radioisotope generator systems have traditionally played a central role in nuclear medicine in providing radioisotopes for both research and clinical applications. In this paper, the development of several tungsten-188/rhenium-188 prototype generators which provide rhenium-188 for radioimmunotherapy (RAIT) is discussed. The authors have recently demonstrated that carrier-free iridium-194 can be obtained from the activated carbon system from decay of reactor-produced osmium-194 for potential RAIT applications. Instrumentation advances such as the new generation of high-count-rate (fast) gamma camera systems for first-pass technology require the availability of generator-produced ultra short-lived radioisotopes for radionuclide angiography (RNA). The activated carbon generator is an efficient system to obtain ultra short-lived iridium-191 m from osmium-191 for RNA. In addition, the growing number of PET centers has stimulated research in generators which provide positron-emitting radioisotopes. Copper-62, obtained from the zinc-62 generator, is currently used for PET evaluation of organ perfusion. The availability of the parent radioisotopes, the fabrication and use of these generators, and the practical factors for use of these systems in the radiopharmacy are discussed. 74 refs., 6 figs., 5 tabs

Perspectives on the development of next generation reactor systems safety analysis codes

International Nuclear Information System (INIS)

Zhang, H.

2015-01-01

'Full text:' Existing reactor system analysis codes, such as RELAP5-3D and TRAC, have gained worldwide success in supporting reactor safety analyses, as well as design and licensing of new reactors. These codes are important assets to the nuclear engineering research community, as well as to the nuclear industry. However, most of these codes were originally developed during the 1970s', and it becomes necessary to develop next-generation reactor system analysis codes for several reasons. Firstly, as new reactor designs emerge, there are new challenges emerging in numerical simulations of reactor systems such as long lasting transients and multi-physics phenomena. These new requirements are beyond the range of applicability of the existing system analysis codes. Advanced modeling and numerical methods must be taken into consideration to improve the existing capabilities. Secondly, by developing next-generation reactor system analysis codes, the knowledge (know how) in two phase flow modeling and the highly complex constitutive models will be transferred to the young generation of nuclear engineers. And thirdly, all computer codes have limited shelf life. It becomes less and less cost-effective to maintain a legacy code, due to the fast change of computer hardware and software environment. There are several critical perspectives in terms of developing next-generation reactor system analysis codes: 1) The success of the next-generation codes must be built upon the success of the existing codes. The knowledge of the existing codes, not just simply the manuals and codes, but knowing why and how, must be transferred to the next-generation codes. The next-generation codes should encompass the capability of the existing codes. The shortcomings of existing codes should be identified, understood, and properly categorized, for example into model deficiencies or numerical method deficiencies. 2) State-of-the-art models and numerical methods must be considered to

Perspectives on the development of next generation reactor systems safety analysis codes

Energy Technology Data Exchange (ETDEWEB)

Zhang, H., E-mail: Hongbin.Zhang@inl.gov [Idaho National Laboratory, Idaho Falls, ID (United States)

2015-07-01

'Full text:' Existing reactor system analysis codes, such as RELAP5-3D and TRAC, have gained worldwide success in supporting reactor safety analyses, as well as design and licensing of new reactors. These codes are important assets to the nuclear engineering research community, as well as to the nuclear industry. However, most of these codes were originally developed during the 1970s', and it becomes necessary to develop next-generation reactor system analysis codes for several reasons. Firstly, as new reactor designs emerge, there are new challenges emerging in numerical simulations of reactor systems such as long lasting transients and multi-physics phenomena. These new requirements are beyond the range of applicability of the existing system analysis codes. Advanced modeling and numerical methods must be taken into consideration to improve the existing capabilities. Secondly, by developing next-generation reactor system analysis codes, the knowledge (know how) in two phase flow modeling and the highly complex constitutive models will be transferred to the young generation of nuclear engineers. And thirdly, all computer codes have limited shelf life. It becomes less and less cost-effective to maintain a legacy code, due to the fast change of computer hardware and software environment. There are several critical perspectives in terms of developing next-generation reactor system analysis codes: 1) The success of the next-generation codes must be built upon the success of the existing codes. The knowledge of the existing codes, not just simply the manuals and codes, but knowing why and how, must be transferred to the next-generation codes. The next-generation codes should encompass the capability of the existing codes. The shortcomings of existing codes should be identified, understood, and properly categorized, for example into model deficiencies or numerical method deficiencies. 2) State-of-the-art models and numerical methods must be considered to

Fuzzy logic based variable speed wind generation system

Energy Technology Data Exchange (ETDEWEB)

Simoes, M.G. [Sao Paulo Univ., SP (Brazil). Escola Politecnica. PMC - Mecatronica; Bose, B.K. [Tennessee Univ., Knoxville, TN (United States). Dept. of Electrical Engineering; Spiegel, Ronal J. [Environmental Protection Agency, Research Triangle Park, NC (United States). Air and Energy Engineering Research Lab.

1996-12-31

This work demonstrates the successful application of fuzzy logic to enhance the performance and control of a variable speed wind generation system. A maximum power point tracker control is performed with three fuzzy controllers, without wind velocity measurement, and robust to wind vortex and turbine torque ripple. A squirrel cage induction generator feeds the power to a double-sided PWM converter system which pumps the power to a utility grid or supplies to an autonomous system. The fuzzy logic controller FLC-1 searches on-line the generator speed so that the aerodynamic efficiency of the wind turbine is optimized. A second fuzzy controller FLC-2 programs the machine flux by on-line search so as to optimize the machine-converter system wind vortex. Detailed analysis and simulation studies were performed for development of the control strategy and fuzzy algorithms, and a DSP TMS320C30 based hardware with C control software was built for the performance evaluation of a laboratory experimental set-up. The theoretical development was fully validated and the system is ready to be reproduced in a higher power installation. (author) 7 refs., 3 figs., 1 tab.

High-Performance Constant Power Generation in Grid-Connected PV Systems

DEFF Research Database (Denmark)

Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

2016-01-01

An advanced power control strategy by limiting the maximum feed-in power of PV systems has been proposed, which can ensure a fast and smooth transition between maximum power point tracking and Constant Power Generation (CPG). Regardless of the solar irradiance levels, high-performance and stable...... operation are always achieved by the proposed control strategy. It can regulate the PV output power according to any set-point, and force the PV systems to operate at the left side of the maximum power point without stability problems. Experimental results have verified the effectiveness of the proposed CPG...

Intelligent control of energy-saving power generation system

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhiyuan; Zhang, Guoqing; Guo, Zhizhong [Harbin Institute of Technology, Harbin (China). Dept. of Electrical Engineering

2013-07-01

Highway power generation system which is environmentally friendly and sustainable provides an innovative method of energy conversion. It is also as a kind of city science and technology innovation, which has the characteristics of environmental protection and sustainable utilization. Making full use of vehicle impact speed control humps, we design a new kind of highway speed control humps combined with solar electric generation system integration. Developing green energy, energy saving and environment protection can be achieved.

A Positive Generation Effect on Memory for Auditory Context.

Science.gov (United States)

Overman, Amy A; Richard, Alison G; Stephens, Joseph D W

2017-06-01

Self-generation of information during memory encoding has large positive effects on subsequent memory for items, but mixed effects on memory for contextual information associated with items. A processing account of generation effects on context memory (Mulligan in Journal of Experimental Psychology: Learning, Memory, and Cognition, 30(4), 838-855, 2004; Mulligan, Lozito, & Rosner in Journal of Experimental Psychology: Learning, Memory, and Cognition, 32(4), 836-846, 2006) proposes that these effects depend on whether the generation task causes any shift in processing of the type of context features for which memory is being tested. Mulligan and colleagues have used this account to predict various negative effects of generation on context memory, but the account also predicts positive generation effects under certain circumstances. The present experiment provided a critical test of the processing account by examining how generation affected memory for auditory rather than visual context. Based on the processing account, we predicted that generation of rhyme words should enhance processing of auditory information associated with the words (i.e., voice gender), whereas generation of antonym words should have no effect. These predictions were confirmed, providing support to the processing account.

OCSEGen: Open Components and Systems Environment Generator

Science.gov (United States)

Tkachuk, Oksana

2014-01-01

To analyze a large system, one often needs to break it into smaller components.To analyze a component or unit under analysis, one needs to model its context of execution, called environment, which represents the components with which the unit interacts. Environment generation is a challenging problem, because the environment needs to be general enough to uncover unit errors, yet precise enough to make the analysis tractable. In this paper, we present a tool for automated environment generation for open components and systems. The tool, called OCSEGen, is implemented on top of the Soot framework. We present the tool's current support and discuss its possible future extensions.

Impacts of intermittent renewable generation on electricity system costs

International Nuclear Information System (INIS)

Batalla-Bejerano, Joan; Trujillo-Baute, Elisa

2016-01-01

A successful deployment of power generation coming from variable renewable sources, such as wind and solar photovoltaic, strongly depends on the economic cost of system integration. This paper, in seeking to look beyond the impact of renewable generation on the evolution of the total economic costs associated with the operation of the electricity system, aims to estimate the sensitivity of balancing market requirements and costs to the variable and non-fully predictable nature of intermittent renewable generation. The estimations reported in this paper for the Spanish electricity system stress the importance of both attributes as well as power system flexibility when accounting for the cost of balancing services. - Highlights: •A successful deployment of VRES-E strongly depends on the economic cost of its integration. •We estimate the sensitivity of balancing market requirements and costs to VRES-E. •Integration costs depend on variability, predictability and system flexibility.

Performance evaluation of microturbine generation system for microgrid applications

Energy Technology Data Exchange (ETDEWEB)

Salam, A.A.; Mohamed, A.; Hannan, M.A.; Shareef, H.; Wanik, M.Z.C. [Kebangsaan Malaysia Univ., Selangor (Malaysia). Dept. of Electrical, Electronic and Systems Engineering, Faculty of Engineering and Built Environment

2009-03-11

A control system for microturbine generation system (MGS) units in microgrid applications was presented. A dynamic model of the microturbine and power electronics interface systems was used to determine converter control strategies for distributed generation operation. Back-to-back converters were used to interface the microturbine-based distributed generation system to the grid. The controllers were used to regulate the output voltage value at the reference bus voltage and the frequency of the whole grid. Reference values were predetermined in the control scheme in order to obtain the desired value of voltage amplitude and frequency. An investigation of system dynamics was conducted using simulations in both grid-connected and islanded modes. Results of the simulations demonstrated the ability of the MGS to improve electricity grid reliability. The model can be used to accurately simulate MGS dynamic performance for both grid- and islanded modes of operation. 10 refs., 17 figs.

Second law comparison of single effect and double effect vapour absorption refrigeration systems

International Nuclear Information System (INIS)

Gomri, Rabah

2009-01-01

In this paper a comparative study between single effect and double effect absorption refrigeration systems with identical cold output is carried out. Simulation results were used to study the influence of the various operating parameters on the performance coefficient, the thermal loads of the components, exergetic efficiency (rational efficiency) and the total change in exergy of the two systems. It is concluded that the COP of double effect system is approximately twice the COP of single effect system but the exergetic efficiency of double effect system increase slightly compared to the exergetic efficiency of single effect system. It is found that for each condenser and evaporator temperature, there is an optimum generator temperature where the total change in exergy of the single effect and double effect absorption refrigeration systems is minimum. At this point the COP and exergetic efficiency of the systems become maximum. In this study and when the evaporation temperature is varied from 4 deg. C to 10 deg. C, condenser and absorber temperatures are varied from 33 deg. C to 39 deg. C and generator (HPG) temperature is varied from 60 deg. C to 190 deg. C the maximum COP values of the single effect refrigeration systems are in the range of 0.73-0.79 and for double effect refrigeration systems are in the range of 1.22-1.42. The maximum exergetic efficiency values of the single effect refrigeration systems are in the range of 12.5-23.2% and for double effect refrigeration systems are in the range of 14.3-25.1%.

Voltage Control System of A DC Generator Using PLC

Directory of Open Access Journals (Sweden)

Subrata CHATTOPADHYAY

2008-06-01

Full Text Available The voltage control system of a DC generator may suffer from high frequency oscillations without offset or low frequency oscillation with offset. A PID controller can eliminate both these errors. In the present paper, the voltage control system of a DC generator using a PLC based PID controller has been designed. Operation of PLC as a continuous controller has been described and the load characteristic of DC generator with and without controller have been determined experimentally and reported in this paper.

Paradigm shift in urban energy systems through distributed generation: Methods and models

International Nuclear Information System (INIS)

Manfren, Massimiliano; Caputo, Paola; Costa, Gaia

2011-01-01

The path towards energy sustainability is commonly referred to the incremental adoption of available technologies, practices and policies that may help to decrease the environmental impact of energy sector, while providing an adequate standard of energy services. The evaluation of trade-offs among technologies, practices and policies for the mitigation of environmental problems related to energy resources depletion requires a deep knowledge of the local and global effects of the proposed solutions. While attempting to calculate such effects for a large complex system like a city, an advanced multidisciplinary approach is needed to overcome difficulties in modeling correctly real phenomena while maintaining computational transparency, reliability, interoperability and efficiency across different levels of analysis. Further, a methodology that rationally integrates different computational models and techniques is necessary to enable collaborative research in the field of optimization of energy efficiency strategies and integration of renewable energy systems in urban areas. For these reasons, a selection of currently available models for distributed generation planning and design is presented and analyzed in the perspective of gathering their capabilities in an optimization framework to support a paradigm shift in urban energy systems. This framework embodies the main concepts of a local energy management system and adopts a multicriteria perspective to determine optimal solutions for providing energy services through distributed generation.

ptxD gene in combination with phosphite serves as a highly effective selection system to generate transgenic cotton (Gossypium hirsutum L.).

Science.gov (United States)

Pandeya, Devendra; Campbell, LeAnne M; Nunes, Eugenia; Lopez-Arredondo, Damar L; Janga, Madhusudhana R; Herrera-Estrella, Luis; Rathore, Keerti S

2017-12-01

This report demonstrates the usefulness of ptxD/phosphite as a selection system that not only provides a highly efficient and simple means to generate transgenic cotton plants, but also helps address many of the concerns related to the use of antibiotic and herbicide resistance genes in the production of transgenic crops. Two of the most popular dominant selectable marker systems for plant transformation are based on either antibiotic or herbicide resistance genes. Due to concerns regarding their safety and in order to stack multiple traits in a single plant, there is a need for alternative selectable marker genes. The ptxD gene, derived from Pseudomonas stutzeri WM88, that confers to cells the ability to convert phosphite (Phi) into orthophosphate (Pi) offers an alternative selectable marker gene as demonstrated for tobacco and maize. Here, we show that the ptxD gene in combination with a protocol based on selection medium containing Phi, as the sole source of phosphorus (P), can serve as an effective and efficient system to select for transformed cells and generate transgenic cotton plants. Fluorescence microscopy examination of the cultures under selection and molecular analyses on the regenerated plants demonstrate the efficacy of the system in recovering cotton transformants following Agrobacterium-mediated transformation. Under the ptxD/Phi selection, an average of 3.43 transgenic events per 100 infected explants were recovered as opposed to only 0.41% recovery when bar/phosphinothricin (PPT) selection was used. The event recovery rates for nptII/kanamycin and hpt/hygromycin systems were 2.88 and 2.47%, respectively. Molecular analysis on regenerated events showed a selection efficiency of ~ 97% under the ptxD/Phi system. Thus, ptxD/Phi has proven to be a very efficient, positive selection system for the generation of transgenic cotton plants with equal or higher transformation efficiencies compared to the commonly used, negative selection systems.

Next-generation mammalian genetics toward organism-level systems biology.

Science.gov (United States)

Susaki, Etsuo A; Ukai, Hideki; Ueda, Hiroki R

2017-01-01

Organism-level systems biology in mammals aims to identify, analyze, control, and design molecular and cellular networks executing various biological functions in mammals. In particular, system-level identification and analysis of molecular and cellular networks can be accelerated by next-generation mammalian genetics. Mammalian genetics without crossing, where all production and phenotyping studies of genome-edited animals are completed within a single generation drastically reduce the time, space, and effort of conducting the systems research. Next-generation mammalian genetics is based on recent technological advancements in genome editing and developmental engineering. The process begins with introduction of double-strand breaks into genomic DNA by using site-specific endonucleases, which results in highly efficient genome editing in mammalian zygotes or embryonic stem cells. By using nuclease-mediated genome editing in zygotes, or ~100% embryonic stem cell-derived mouse technology, whole-body knock-out and knock-in mice can be produced within a single generation. These emerging technologies allow us to produce multiple knock-out or knock-in strains in high-throughput manner. In this review, we discuss the basic concepts and related technologies as well as current challenges and future opportunities for next-generation mammalian genetics in organism-level systems biology.

Natural Language Generation for dialogue: system survey

NARCIS (Netherlands)

Theune, Mariet

Many natural language dialogue systems make use of `canned text' for output generation. This approach may be su±cient for dialogues in restricted domains where system utterances are short and simple and use fixed expressions (e.g., slot filling dialogues in the ticket reservation or travel

A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

DEFF Research Database (Denmark)

Sun, Kai; Zhang, Li; Xing, Yan

2011-01-01

on improved dc bus signaling is proposed for a modular photovoltaic (PV) generation system with battery energy storage elements. In this paper, the modular PV generation system is composed of three modular dc/dc converters for PV arrays, two grid-connected dc/ac converters, and one dc/dc converter for battery......, grid-connected inversion, and islanding with constant voltage (CV) generation.The power balance of the system under extreme conditions such as the islanding operation with a full-charged battery is taken into account in this control strategy. The dc bus voltage level is employed as an information......Modular generation system, which consists of modular power conditioning converters, is an effective solution to integrate renewable energy sources with conventional utility grid to improve reliability and efficiency, especially for photovoltaic generation. A distributed control strategy based...

Innovation of blow-down system in steam generators of a VVER 440 unit

International Nuclear Information System (INIS)

Matal, O.; Simo, T.; Mancev, M.D.

1997-01-01

The impurities getting into the steam generator with the feedwater are continually removed by the blowdown and unit sludge system. The mostly non-symmetrical type of pipe branches under steam generators at WWER-440 units causes nonuniform blowdown flow rates at the halves of the steam generator; this often leads to a blocking of the pipe with the lower flow rate. The most simple way of hydraulically equalizing the blowdown pipes is to implement symmetric blowdown pipes and to install efficient throttling elements in the pipe. The proposed innovation will make it possible to re-distribute the blowdown flow rates and to reduce more effectively the concentrations of impurities in steam generators. (M.D.)

Experimental study of a sustainable hybrid system for thermoelectric generation and freshwater production

Science.gov (United States)

de Souza, Gabriel Fernandes; Tan, Lippong; Singh, Baljit; Ding, Lai Chet; Date, Abhijit

2017-04-01

The paper presents a sustainable hybrid system, which is capable of generating electricity and producing freshwater from seawater using low grade heat source. This proposed system uses low grade heat that can be supplied from solar radiation, industrial waste heat or any other waste heat sources where the temperature is less than 150°C. The concept behind this system uses the Seebeck effect for thermoelectricity generation via incorporating the low boiling point of seawater under sub-atmospheric ambient pressure. A lab-test prototype of the proposed system was built and experimentally tested in RMIT University. The prototype utilised four commercial available thermoelectric generators (Bi2Te3) and a vacuum vessel to achieve the simultaneous production of electricity and freshwater. The temperature profiles, thermoelectric powers and freshwater productions were determined at several levels of salinity to study the influence of different salt concentrations. The theoretical description of system design and experimental results were analysed and discussed in detailed. The experiment results showed that 0.75W of thermoelectricity and 404g of freshwater were produced using inputs of 150W of simulated waste heat and 500g of 3% saline water. The proposed hybrid concept has demonstrated the potential to become the future sustainable system for electricity and freshwater productions.

Dispersed generation: impact on the electricity system

International Nuclear Information System (INIS)

Delfanti, M.; Merlo, M.; Silvestri, A.

2009-01-01

The paper deals with the impact of Dispersed Generation (D G) on the national electricity system, by proposing a practical approach for determining the current capacity of the networks to accepts this form of generation (hosting capacity). With the prospect of an increasing intake of D G, we finally draft a possible evolution of distribution networks based on the integration of energy and information networks. [it

Memory Saves Lives: Inter-generational Warnings Effectiveness - 13556

International Nuclear Information System (INIS)

Van Luik, Abraham; Patterson, Russell; Shafer, David; Klein, Thomas

2013-01-01

The 2011 Tohoku earthquake and tsunami was a world-class natural disaster. It has been described as the most powerful earthquake ever in Japan, and as one of the most powerful earthquakes ever noted in the world. The toll in terms of human lives lost and property destruction was unimaginable. Even the word 'horrible' is inadequate to describe the suffering and misery that resulted. Nations with nuclear power programs are engaged in, or at least planning to become engaged in, arranging to eventually dispose of their higher-level radioactive waste materials in deep geologic repositories. Geologic repositories are passive safety systems, and if undisturbed isolate these dangerous materials form the biosphere for extremely long times. The key words, however, are 'if undisturbed'. To assure that future generations do not inadvertently drill into repositories, national programs, and the international community (the Records, Knowledge and Memory (RK and M) preservation project of the Nuclear Energy Agency, for example), are proposing to place markers and/or monuments on closed repository sites that say 'do not drill here, and this is why' in various sophisticated ways. Such markers or monuments are attempts at providing passive institutional controls. The effectiveness of messages from past generations to a present generation may give an indication of how effective such passive institutional controls may be. (authors)

Integration of steam injection and inlet air cooling for a gas turbine generation system

International Nuclear Information System (INIS)

Wang, F.J.; Chiou, J.S.

2004-01-01

The temperature of exhaust gases from simple cycle gas turbine generation sets (GENSETs) is usually very high (around 500 deg. C), and a heat recovery steam generator (HRSG) is often used to recover the energy from the exhaust gases and generate steam. The generated steams can be either used for many useful processes (heating, drying, separation etc.) or used back in the power generation system for enhancing power generation capacity and efficiency. Two well-proven techniques, namely steam injection gas turbine (STIG) and inlet air cooling (IAC) are very effective features that can use the generated steam to improve the power generation capacity and efficiency. Since the energy level of the generated steam needed for steam injection is different from that needed by an absorption chiller to cool the inlet air, a proper arrangement is required to implement both the STIG and the IAC features into the simple cycle GENSET. In this study, a computer code was developed to simulate a Tai power's Frame 7B simple cycle GENSET. Under the condition of local summer weather, the benefits obtained from the system implementing both STIG and IAC features are more than a 70% boost in power and 20.4% improvement in heat rate

Research and development of evaluation system for photovoltaic power generation system. Research and development on evaluation technology of photovoltaic power generating systems; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. System hyoka gijutsu no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

This paper reports the study results on R and D of evaluation technology for photovoltaic power generating systems in fiscal 1994. (1) On preparation of test facility and measuring instrument, the pyrheliometer with a photovoltaic device as sensor was developed. (2) On collection and analysis of data, operation data of interconnection system, stand alone system, and water pump system were collected, and energy flow was analyzed. The following were also analyzed: time variation of a-Si solar cell modules, fluctuation correction factor of spectrum response, that of nonlinear response of crystalline solar cells, effect of solar radiation intensity and wind velocity on temperature rise of modules, and correction factor of DC circuit losses. (3) On on-site measurement technology, the array output measuring instrument was developed on the basis of capacitor charge system. (4) On simulation technology, simulation analyses of energy flow, optimum capacity of interconnection systems, correction factor of solar radiation, and capacity of array storage batteries were conducted. 3 figs., 6 tabs.

Development of a framework for the neutronics analysis system for next generation (Contract research)

International Nuclear Information System (INIS)

Tatsumi, Masahiro; Yokoyama, Kenji

2007-11-01

In JAEA, authors has been promoting the development of an object-oriented next-generation neutronics analysis system in order to reflect the latest methods and models of reactor analysis to basic designs and operations of fast reactors in the efficient and effective way. A purpose of the developing system is to effectively realize requirements that has been difficult to manage in the conventional systems, such as change of analysis targets and change of analysis modeling levels. For the realization of the requirements, the authors adopted the two-layer model which consists of a control layer written in the Python as an object-oriented scripting language and a solver layer in the C++ as a system programming language. After having studied the principle on the two-layer model in the next-generation neutronics analysis system, the authors designed and implemented a library that enabled transparent transfer of data objects between the two layers. In each layer, appropriate numerical library was used for better performance. In the present library, a model proxy was implemented to exchange internal data that is represented in different ways in each layer. With this mechanism of the model proxy, it confirmed that data exchange between the layers can be performed easily and effectively. (author)

Grandparental effects in marine sticklebacks: transgenerational plasticity across multiple generations.

Science.gov (United States)

Shama, L N S; Wegner, K M

2014-11-01

Nongenetic inheritance mechanisms such as transgenerational plasticity (TGP) can buffer populations against rapid environmental change such as ocean warming. Yet, little is known about how long these effects persist and whether they are cumulative over generations. Here, we tested for adaptive TGP in response to simulated ocean warming across parental and grandparental generations of marine sticklebacks. Grandparents were acclimated for two months during reproductive conditioning, whereas parents experienced developmental acclimation, allowing us to compare the fitness consequences of short-term vs. prolonged exposure to elevated temperature across multiple generations. We found that reproductive output of F1 adults was primarily determined by maternal developmental temperature, but carry-over effects from grandparental acclimation environments resulted in cumulative negative effects of elevated temperature on hatching success. In very early stages of growth, F2 offspring reached larger sizes in their respective paternal and grandparental environment down the paternal line, suggesting that other factors than just the paternal genome may be transferred between generations. In later growth stages, maternal and maternal granddam environments strongly influenced offspring body size, but in opposing directions, indicating that the mechanism(s) underlying the transfer of environmental information may have differed between acute and developmental acclimation experienced by the two generations. Taken together, our results suggest that the fitness consequences of parental and grandparental TGP are highly context dependent, but will play an important role in mediating some of the impacts of rapid climate change in this system. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Mathematical modeling of control system for the experimental steam generator

Directory of Open Access Journals (Sweden)

Podlasek Szymon

2016-01-01

Full Text Available A steam generator is an essential unit of each cogeneration system using steam machines. Currently one of the cheapest ways of the steam generation can be application of old steam generators came from army surplus store. They have relatively simple construction and in case of not so exploited units – quite good general conditions, and functionality of mechanical components. By contrast, electrical components and control systems (mostly based on relay automatics are definitely obsolete. It is not possible to use such units with cooperation of steam bus or with steam engines. In particular, there is no possibility for automatically adjustment of the pressure and the temperature of the generated steam supplying steam engines. Such adjustment is necessary in case of variation of a generator load. The paper is devoted to description of improvement of an exemplary unit together with construction of the measurement-control system based on a PLC. The aim was to enable for communication between the steam generator and controllers of the steam bus and steam engines in order to construction of a complete, fully autonomic and maintenance-free microcogeneration system.

Instrumentation and control of turbine, generator and associated systems

International Nuclear Information System (INIS)

Vogtland, U.

1982-01-01

The purpose of this presentation is to give some information on Instrumentation and Control (I and C) for turbine-generators, in this case for nuclear application. The I and C scope of supply for such a turbine-generator can be divided as follows: - Closed-loop controls - Turbine stress control systems - Supervisory instrumentation - Protection systems - Open-loop controls. The main systems used for nuclear application are presented by means of examples taken from these a.m. categories. (orig./RW)

Development in fiscal 1999 of technology commercializing photovoltaic power generation system. Research and development of power generation application system and peripheral technologies (Survey and research on evaluation of photovoltaic power generation); 1999 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Taiyoko hatsuden riyo system shuhen gijutsu no kenkyu kaihatsu (taiyoko hatsuden hyoka no chosa kenkyu)

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

With an objective of evaluating the contribution to the global environment of utilization of photovoltaic power generation, discussions were given on evaluation of photovoltaic system life cycle, evaluation of contribution to environment, and total evaluation. This paper summarizes the achievements in fiscal 1999. In evaluating the PV system life cycle, the roof-integrated modules using the thin film CdTe cells were selected as the evaluation object to estimate the energy payback time (EPT) and the CO2 emission unit consumption rate. In case of annual production of 10 MW, the EPT is 1.8 years and the CO2 emission unit consumption rate is 13 (g-C/kWh), which were found largely reducible by expanding the annual production size. For the environmental contribution evaluation which focuses on CO2 emission suppression effect as the discussion object, discussions are being given on the introduction scenario needed for the analysis. In the total evaluation, the direct employment effect assumed in Japan was discussed on production, distribution sales, installation, maintenance control and dismantling of photovoltaic generation system for residential use. The discussion showed the effect of about 7 persons per year per MW in production size of 100 MW. (NEDO)

SITE GENERATED RADIOLOGICAL WASTE HANDLING SYSTEM DESCRIPTION DOCUMENT

Energy Technology Data Exchange (ETDEWEB)

S. C. Khamankar

2000-06-20

The Site Generated Radiological Waste Handling System handles radioactive waste products that are generated at the geologic repository operations area. The waste is collected, treated if required, packaged for shipment, and shipped to a disposal site. Waste streams include low-level waste (LLW) in solid and liquid forms, as-well-as mixed waste that contains hazardous and radioactive constituents. Liquid LLW is segregated into two streams, non-recyclable and recyclable. The non-recyclable stream may contain detergents or other non-hazardous cleaning agents and is packaged for shipment. The recyclable stream is treated to recycle a large portion of the water while the remaining concentrated waste is packaged for shipment; this greatly reduces the volume of waste requiring disposal. There will be no liquid LLW discharge. Solid LLW consists of wet solids such as ion exchange resins and filter cartridges, as-well-as dry active waste such as tools, protective clothing, and poly bags. Solids will be sorted, volume reduced, and packaged for shipment. The generation of mixed waste at the Monitored Geologic Repository (MGR) is not planned; however, if it does come into existence, it will be collected and packaged for disposal at its point of occurrence, temporarily staged, then shipped to government-approved off-site facilities for disposal. The Site Generated Radiological Waste Handling System has equipment located in both the Waste Treatment Building (WTB) and in the Waste Handling Building (WHB). All types of liquid and solid LLW are processed in the WTB, while wet solid waste from the Pool Water Treatment and Cooling System is packaged where received in the WHB. There is no installed hardware for mixed waste. The Site Generated Radiological Waste Handling System receives waste from locations where water is used for decontamination functions. In most cases the water is piped back to the WTB for processing. The WTB and WHB provide staging areas for storing and shipping LLW

SITE GENERATED RADIOLOGICAL WASTE HANDLING SYSTEM DESCRIPTION DOCUMENT

International Nuclear Information System (INIS)

S. C. Khamankar

2000-01-01

The Site Generated Radiological Waste Handling System handles radioactive waste products that are generated at the geologic repository operations area. The waste is collected, treated if required, packaged for shipment, and shipped to a disposal site. Waste streams include low-level waste (LLW) in solid and liquid forms, as-well-as mixed waste that contains hazardous and radioactive constituents. Liquid LLW is segregated into two streams, non-recyclable and recyclable. The non-recyclable stream may contain detergents or other non-hazardous cleaning agents and is packaged for shipment. The recyclable stream is treated to recycle a large portion of the water while the remaining concentrated waste is packaged for shipment; this greatly reduces the volume of waste requiring disposal. There will be no liquid LLW discharge. Solid LLW consists of wet solids such as ion exchange resins and filter cartridges, as-well-as dry active waste such as tools, protective clothing, and poly bags. Solids will be sorted, volume reduced, and packaged for shipment. The generation of mixed waste at the Monitored Geologic Repository (MGR) is not planned; however, if it does come into existence, it will be collected and packaged for disposal at its point of occurrence, temporarily staged, then shipped to government-approved off-site facilities for disposal. The Site Generated Radiological Waste Handling System has equipment located in both the Waste Treatment Building (WTB) and in the Waste Handling Building (WHB). All types of liquid and solid LLW are processed in the WTB, while wet solid waste from the Pool Water Treatment and Cooling System is packaged where received in the WHB. There is no installed hardware for mixed waste. The Site Generated Radiological Waste Handling System receives waste from locations where water is used for decontamination functions. In most cases the water is piped back to the WTB for processing. The WTB and WHB provide staging areas for storing and shipping LLW

A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

Science.gov (United States)

Chamberlain, R. G.; McMaster, K. M.

1981-10-01

The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

Science.gov (United States)

Chamberlain, R. G.; Mcmaster, K. M.

1981-01-01

The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

Models for Numerical Evaluation of Variable Speed Different Wind Generator Systems

DEFF Research Database (Denmark)

Li, Hui; Chen, Zhe; Polinder, H.

2007-01-01

of different wind generator systems, the other presents the optimization results and evaluation of variable speed wind generator systems. In this report, firstly, it gives an overview of various wind generator topologies, including their advantages and disadvantages, market status and developing trends. Next...

Reliability assessment of distribution system with the integration of renewable distributed generation

International Nuclear Information System (INIS)

Adefarati, T.; Bansal, R.C.

2017-01-01

Highlights: • Addresses impacts of renewable DG on the reliability of the distribution system. • Multi-objective formulation for maximizing the cost saving with integration of DG. • Uses Markov model to study the stochastic characteristics of the major components. • The investigation is done using modified RBTS bus test distribution system. • Proposed approach is useful for electric utilities to enhance the reliability. - Abstract: Recent studies have shown that renewable energy resources will contribute substantially to future energy generation owing to the rapid depletion of fossil fuels. Wind and solar energy resources are major sources of renewable energy that have the ability to reduce the energy crisis and the greenhouse gases emitted by the conventional power plants. Reliability assessment is one of the key indicators to measure the impact of the renewable distributed generation (DG) units in the distribution networks and to minimize the cost that is associated with power outage. This paper presents a comprehensive reliability assessment of the distribution system that satisfies the consumer load requirements with the penetration of wind turbine generator (WTG), electric storage system (ESS) and photovoltaic (PV). A Markov model is proposed to access the stochastic characteristics of the major components of the renewable DG resources as well as their influence on the reliability of a conventional distribution system. The results obtained from the case studies have demonstrated the effectiveness of using WTG, ESS and PV to enhance the reliability of the conventional distribution system.

High-power density miniscale power generation and energy harvesting systems

International Nuclear Information System (INIS)

Lyshevski, Sergey Edward

2011-01-01

This paper reports design, analysis, evaluations and characterization of miniscale self-sustained power generation systems. Our ultimate objective is to guarantee highly-efficient mechanical-to-electrical energy conversion, ensure premier wind- or hydro-energy harvesting capabilities, enable electric machinery and power electronics solutions, stabilize output voltage, etc. By performing the advanced scalable power generation system design, we enable miniscale energy sources and energy harvesting technologies. The proposed systems integrate: (1) turbine which rotates a radial- or axial-topology permanent-magnet synchronous generator at variable angular velocity depending on flow rate, speed and load, and, (2) power electronic module with controllable rectifier, soft-switching converter and energy storage stages. These scalable energy systems can be utilized as miniscale auxiliary and self-sustained power units in various applications, such as, aerospace, automotive, biotechnology, biomedical, and marine. The proposed systems uniquely suit various submersible and harsh environment applications. Due to operation in dynamic rapidly-changing envelopes (variable speed, load changes, etc.), sound solutions are researched, proposed and verified. We focus on enabling system organizations utilizing advanced developments for various components, such as generators, converters, and energy storage. Basic, applied and experimental findings are reported. The prototypes of integrated power generation systems were tested, characterized and evaluated. It is documented that high-power density, high efficiency, robustness and other enabling capabilities are achieved. The results and solutions are scalable from micro (∼100 μW) to medium (∼100 kW) and heavy-duty (sub-megawatt) auxiliary and power systems.

Optimal power system generation scheduling by multi-objective genetic algorithms with preferences

International Nuclear Information System (INIS)

Zio, E.; Baraldi, P.; Pedroni, N.

2009-01-01

Power system generation scheduling is an important issue both from the economical and environmental safety viewpoints. The scheduling involves decisions with regards to the units start-up and shut-down times and to the assignment of the load demands to the committed generating units for minimizing the system operation costs and the emission of atmospheric pollutants. As many other real-world engineering problems, power system generation scheduling involves multiple, conflicting optimization criteria for which there exists no single best solution with respect to all criteria considered. Multi-objective optimization algorithms, based on the principle of Pareto optimality, can then be designed to search for the set of nondominated scheduling solutions from which the decision-maker (DM) must a posteriori choose the preferred alternative. On the other hand, often, information is available a priori regarding the preference values of the DM with respect to the objectives. When possible, it is important to exploit this information during the search so as to focus it on the region of preference of the Pareto-optimal set. In this paper, ways are explored to use this preference information for driving a multi-objective genetic algorithm towards the preferential region of the Pareto-optimal front. Two methods are considered: the first one extends the concept of Pareto dominance by biasing the chromosome replacement step of the algorithm by means of numerical weights that express the DM' s preferences; the second one drives the search algorithm by changing the shape of the dominance region according to linear trade-off functions specified by the DM. The effectiveness of the proposed approaches is first compared on a case study of literature. Then, a nonlinear, constrained, two-objective power generation scheduling problem is effectively tackled

Next generation Zero-Code control system UI

CERN Multimedia

CERN. Geneva

2017-01-01

Developing ergonomic user interfaces for control systems is challenging, especially during machine upgrade and commissioning where several small changes may suddenly be required. Zero-code systems, such as *Inspector*, provide agile features for creating and maintaining control system interfaces. More so, these next generation Zero-code systems bring simplicity and uniformity and brake the boundaries between Users and Developers. In this talk we present *Inspector*, a CERN made Zero-code application development system, and we introduce the major differences and advantages of using Zero-code control systems to develop operational UI.

Stirling engine based micro co-generation system for single households

Energy Technology Data Exchange (ETDEWEB)

Ribberink, H.; Zutt, S.; Rabou, L.; Beckers, G. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Baijens, K.; Luttikholt, J. [Atag Verwarming BV (Netherlands)

2000-07-01

This paper describes the progress made in the ENATEC development program for a free piston Stirling engine based micro co-generation system that serves the supply of up to 1 kW{sub e} and up to 24 kW heat for domestic heating and/or for hot tap water production for single households at overall system efficiencies of 96%: Experiments show that the free piston Stirling engines from Stirling Technology Company run very reliably and controllably, and that the efficiency targets for the 1 kW{sub e} micro co-generation system are feasible. A ceramic foam burner with good heat transfer characteristics and low NOx emissions was developed. A demonstration micro co-generation unit was built and successfully presented. A 1 kW{sub e} free piston Stirling engine for the European market was developed. High efficiencies at full load and at part load, low emissions, low noise, and minimum maintenance make the Stirling engine based micro co-generation system an attractive candidate for the next generation of domestic boilers in Europe. (orig.)

Development of condition monitoring and diagnosis system for standby diesel generator

Energy Technology Data Exchange (ETDEWEB)

Choi, Kwang Hee; Park, Jong Hyuck; Park, Jong Eun [Korea Electric Power Research Institute, Daejeon (Korea, Republic of)

2009-05-15

The emergency diesel generator (EDG) of the nuclear power plant is designed to supply the power to the nuclear on Station Black Out (SBO) condition. The operation reliability of onsite emergency diesel generator should be ensured by a condition monitoring system designed to monitor and analysis the condition of diesel generator. For this purpose, we have developed the online condition monitoring and diagnosis system for the wolsong unit 3 and 4 standby diesel generator including diesel engine performance. In this paper, technologies of condition monitoring and diagnosis system (SDG MDS) for the wolsong standby diesel generator are described. By using the condition monitoring module of the SDG MDS, performance monitoring function for major operating parameters of EDG reliability program required by Reg. guide 1.155 can be operated as on line monitoring system.

Development of condition monitoring and diagnosis system for standby diesel generator

International Nuclear Information System (INIS)

Choi, Kwang Hee; Park, Jong Hyuck; Park, Jong Eun

2009-01-01

The emergency diesel generator (EDG) of the nuclear power plant is designed to supply the power to the nuclear on Station Black Out (SBO) condition. The operation reliability of onsite emergency diesel generator should be ensured by a condition monitoring system designed to monitor and analysis the condition of diesel generator. For this purpose, we have developed the online condition monitoring and diagnosis system for the wolsong unit 3 and 4 standby diesel generator including diesel engine performance. In this paper, technologies of condition monitoring and diagnosis system (SDG MDS) for the wolsong standby diesel generator are described. By using the condition monitoring module of the SDG MDS, performance monitoring function for major operating parameters of EDG reliability program required by Reg. guide 1.155 can be operated as on line monitoring system

Multi Agent System Based Adaptive Protection for Dispersed Generation Integrated Distribution Systems

DEFF Research Database (Denmark)

Liu, Leo; Rather, Zakir Hussain; Bak, Claus Leth

2013-01-01

The increasing penetration of dispersed generation (DG) brings challenges to conventional protection approaches of distribution system, mainly due to bi-directional power flow and variable fault current contribution from different generation technology-based DG units. Moreover, the trend......) is proposed. The adaptive protection intelligently adopts suitable settings for the variation of fault current from diversified DG units. Furthermore, the structure of mobile MAS with additional flexibility is capable of adapting the changes of system topology in a short period, e.g. radial/meshed, grid...

Optimal design of power system stabilizer for power systems including doubly fed induction generator wind turbines

International Nuclear Information System (INIS)

Derafshian, Mehdi; Amjady, Nima

2015-01-01

This paper presents an evolutionary algorithm-based approach for optimal design of power system stabilizer (PSS) for multi-machine power systems that include doubly fed induction generator wind turbines. The proposed evolutionary algorithm is an improved particle swarm optimization named chaotic particle swarm optimization with passive congregation (CPSO-PC) applied for finding the optimal settings of PSS parameters. Two different eigenvalue-based objectives are combined as the objective function for the optimization problem of tuning PSS parameters. The first objective function comprises the damping factor of lightly damped electro-mechanical modes and the second one includes the damping ratio of these modes. The effectiveness of the proposed method to design PSS for the power systems including DFIG (Doubly Fed Induction Generator) is extensively demonstrated through eigenvalue analysis and time-domain simulations and also by comparing its simulation results with the results of other heuristic optimization approaches. - Highlights: • A new optimization model for design of PSS in power systems including DFIG is proposed. • A detailed and realistic modeling of DFIG is presented. • A new evolutionary algorithm is suggested for solving the optimization problem of designing PSS

Next Generation Nuclear Plant System Requirements Manual

International Nuclear Information System (INIS)

Not Listed

2008-01-01

System Requirements Manual for the NGNP Project. The Energy Policy Act of 2005 (H.R. 6; EPAct), which was signed into law by President George W. Bush in August 2005, required the Secretary of the U.S. Department of Energy (DOE) to establish a project to be known as the Next Generation Nuclear Plant (NGNP) Project. According to the EPAct, the NGNP Project shall consist of the research, development, design, construction, and operation of a prototype plant (to be referred to herein as the NGNP) that (1) includes a nuclear reactor based on the research and development (R and D) activities supported by the Generation IV Nuclear Energy Systems initiative, and (2) shall be used to generate electricity, to produce hydrogen, or to both generate electricity and produce hydrogen. The NGNP Project supports both the national need to develop safe, clean, economical nuclear energy and the Nuclear Hydrogen Initiative (NHI), which has the goal of establishing greenhouse-gas-free technologies for the production of hydrogen. The DOE has selected the helium-cooled High Temperature Gas-Cooled Reactor (HTGR) as the reactor concept to be used for the NGNP because it is the only near-term Generation IV concept that has the capability to provide process heat at high-enough temperatures for highly efficient production of hydrogen. The EPAct also names the Idaho National Laboratory (INL), the DOE's lead national laboratory for nuclear energy research, as the site for the prototype NGNP

Solar photovoltaic power generation system and understanding of green energy

International Nuclear Information System (INIS)

Yoo, Chun Sik

2004-03-01

This book introduces sunlight generation system and green energy, which includes new and renewable energy such as photovoltaic power generation, solar thermal, wind power, bio energy, waste energy, geothermal energy, ocean energy and fuel cell photovoltaic industry like summary, technology trend, market trend, development strategy of the industry in Korea, and other countries, design of photovoltaic power generation system supporting policy and related business of new and renewable energy.

Protective, Modular Wave Power Generation System

Energy Technology Data Exchange (ETDEWEB)

Vvedensky, Jane M.; Park, Robert Y.

2012-11-27

The concept of small wave energy conversion modules that can be built into large, scalable arrays, in the same vein as solar panels, has been developed. This innovation lends itself to an organic business and development model, and enables the use of large-run manufacturing technology to reduce system costs. The first prototype module has been built to full-scale, and tested in a laboratory wave channel. The device has been shown to generate electricity and dissipate wave energy. Improvements need to be made to the electrical generator and a demonstration of an array of modules should be made in natural conditions.

Distributed generation - customer owned generation - Duke Energy case study

Energy Technology Data Exchange (ETDEWEB)

Iung, Anderson M. [Duke Energy International, Geracao Paranapanema S.A., SP (Brazil). Market Analysis Dept.; Ribeiro, Paulo F. [Calvin College, Grand Rapids, MI (United States); Oliveira, A.R. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil)

2009-07-01

Distributed generation (DG) is getting more attractive. Although unit costs show strong economies of scale for all generation technology types, there is a potential niche market for DG technology to drive growth in addition to environmental concern issues. Duke Energy encourages the installation of cost effective small scale costumer owned generation. The objective of this article is to evaluate some aspects of DG connection in the Duke's distribution system regarding power quality, voltage stability, system protection, power balance control policy and the economical viability. (author)

Simulation and Parametric Analysis of a Hybrid SOFC-Gas Turbine Power Generation System

International Nuclear Information System (INIS)

Hassan, A.M.; Fahmy

2004-01-01

Combined SOFC-Gas Turbine Power Generation Systems are aimed to increase the power and efficiency obtained from the technology of using high temperature fuel cells by integrating them with gas turbines. Hybrid systems are considered in the last few years as one of the most promising technologies to obtain electric energy from the natural gas at very high efficiency with a serious potential for commercial use. The use of high temperature allows internal reforming for natural gas and thus disparity of fuel composition is allowed. Also air preheating is performed thanks to the high operating cell temperature as a task of energy integration. In this paper a modeling approach is presented for the fuel cell-gas turbine hybrid power generation systems, to obtain the sofc output voltage, power, and the overall hybrid system efficiency. The system has been simulated using HYSYS, the process simulation software to help improving the process understanding and provide a quick system solution. Parametric analysis is also presented in this paper to discuss the effect of some important SOFC operating parameters on the system performance and efficiency

Tc Generator Development: Up-to-Date Tc Recovery Technologies for Increasing the Effectiveness of Mo Utilisation

Directory of Open Access Journals (Sweden)

Van So Le

2014-01-01

Full Text Available A review on the Mo sources available today and on the Tc generators developed up to date for increasing the effectiveness of Mo utilisation is performed in the format of detailed description of the features and technical performance of the technological groups of the Mo production and Tc recovery. The latest results of the endeavour in this field are also surveyed in regard of the technical solution for overcoming the shortage of Mo supply. The technological topics are grouped and discussed in a way to reflect the similarity in the technological process of each group. The following groups are included in this review which are high specific activity Mo: the current issues of production, the efforts of more effective utilisation, and the high specific activity Mo-based Tc generator and Tc concentration units; low specific activity Mo: the Mo production based on neutron capture and accelerators and the direct production of Tc and the methods of increasing the specific activity of Mo using Szilard-Chalmers reaction and high electric power isotopic separator; up-to-date technologies of Tc recovery from low specific activity Mo: the solvent extraction-based Tc generator, the sublimation methods for Mo/Tc separation, the electrochemical method for Tc recovery, and the column chromatographic methods for Tc recovery. Besides the traditional Tc-generator systems, the integrated Tc generator systems (Tc generator column combined with postelution purification/concentration unit are discussed with the format of process diagram and picture of real generator systems. These systems are the technetium selective sorbent column-based generators, the high Mo-loading capacity column-based integrated Tc generator systems which include the saline-eluted generator systems, and the nonsaline aqueous and organic solvent eluent-eluted generator systems using high Mo-loading capacity molybdategel and recently developed sorbent columns. Tc concentration methods used in the

Technology Road-map Update for Generation IV Nuclear Energy Systems

International Nuclear Information System (INIS)

2014-01-01

This Technology Road-map Update provides an assessment of progress made by the Generation IV International Forum (GIF) in the development of the six systems selected when the original Technology Road-map was published in 2002. More importantly, it provides an overview of the major R and D objectives and milestones for the coming decade, aiming to achieve the Generation IV goals of sustainability, safety and reliability, economic competitiveness, proliferation resistance and physical protection. Lessons learnt from the Fukushima Daiichi nuclear power plant accident are taken into account to ensure that Generation IV systems attain the highest levels of safety, with the development of specific safety design criteria that are applicable across the six systems. Accomplishing the ten-year R and D objectives set out in this new Road-map should allow the more advanced Generation IV systems to move towards the demonstration phase. (authors)

Net energy analysis of different electricity generation systems

International Nuclear Information System (INIS)

1994-07-01

This document is a report on the net energy analysis of nuclear power and other electricity generation systems. The main objectives of this document are: To provide a comprehensive review of the state of knowledge on net energy analysis of nuclear and other energy systems for electricity generation; to address traditional questions such as whether nuclear power is a net energy producer or not. In addition, the work in progress on a renewed application of the net energy analysis method to environmental issues is also discussed. It is expected that this work could contribute to the overall comparative assessment of different energy systems which is an ongoing activity at the IAEA. 167 refs, 9 figs, 5 tabs

On-Line Generation and Arming of System Protection Schemes

DEFF Research Database (Denmark)

Pedersen, Andreas Søndergaard; Blanke, Mogens; Møller, Jakob Glarbo

2016-01-01

This paper presents a new method to automatically generate system protection schemes in real-time, where contingencies are filtered using a method providing N– 1 system snapshots. With future power systems consisting largely of renewable distributed generation with time-varying production, highly....... The method is based on a recently proposed method of calculating post-contingency Thevenin equivalents, which are used to assess the security of the post-contingency condition. The contingencies that violate the emergency limits are contained by pre-determining event-based remedial actions. The instability...

Prototype testing and analysis of a novel internal combustion linear generator integrated power system

Energy Technology Data Exchange (ETDEWEB)

Xu, Zhaoping; Chang, Siqin [School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

2010-04-15

A novel four-stroke free-piston engine equipped with a linear electric generator (namely internal combustion linear generator integrated power system) is proposed in this paper to achieve efficient energy conversion from fuel to electricity. Unique features of the novel power system are presented and their effects on the continuous running are discussed, along with potential advantages and disadvantages compared to conventional engines. A single cylinder, gasoline and spark ignition prototype is fabricated with reference to the geometric and control parameters of an existing conventional four-stroke engine. Stable running of the prototype is realized, and a 2.2 kW average output power with the generating efficiency of 32% has been obtained up to now. The feasibility and performance of the proposed design are verified. Detailed testing results from the continuous running prototype are analyzed in this paper for giving insight into the performance and dynamic behaviors of the novel power system. (author)

High-power density miniscale power generation and energy harvesting systems

Energy Technology Data Exchange (ETDEWEB)

Lyshevski, Sergey Edward [Department of Electrical and Microelectronics Engineering, Rochester Institute of Technology, Rochester, NY 14623-5603 (United States)

2011-01-15

This paper reports design, analysis, evaluations and characterization of miniscale self-sustained power generation systems. Our ultimate objective is to guarantee highly-efficient mechanical-to-electrical energy conversion, ensure premier wind- or hydro-energy harvesting capabilities, enable electric machinery and power electronics solutions, stabilize output voltage, etc. By performing the advanced scalable power generation system design, we enable miniscale energy sources and energy harvesting technologies. The proposed systems integrate: (1) turbine which rotates a radial- or axial-topology permanent-magnet synchronous generator at variable angular velocity depending on flow rate, speed and load, and, (2) power electronic module with controllable rectifier, soft-switching converter and energy storage stages. These scalable energy systems can be utilized as miniscale auxiliary and self-sustained power units in various applications, such as, aerospace, automotive, biotechnology, biomedical, and marine. The proposed systems uniquely suit various submersible and harsh environment applications. Due to operation in dynamic rapidly-changing envelopes (variable speed, load changes, etc.), sound solutions are researched, proposed and verified. We focus on enabling system organizations utilizing advanced developments for various components, such as generators, converters, and energy storage. Basic, applied and experimental findings are reported. The prototypes of integrated power generation systems were tested, characterized and evaluated. It is documented that high-power density, high efficiency, robustness and other enabling capabilities are achieved. The results and solutions are scalable from micro ({proportional_to}100 {mu}W) to medium ({proportional_to}100 kW) and heavy-duty (sub-megawatt) auxiliary and power systems. (author)

Long-Term Reserve Expansion of Power Systems With High Wind Power Penetration Using Universal Generating Function Methods

DEFF Research Database (Denmark)

DING, YI; Wang, Peng; Goel, Lalit

2010-01-01

from long term planning point of view utilizing universal generating function (UGF) methods. The reliability models of wind farms and conventional generators are represented as the correspondin UGFs and the special operators for these UGFs are defined to evaluate the customer and the system...... reliabilities. The effect of transmission network on customer reliabilities is also considered in the system UGF. The power output models of wind turbine generators in a wind farm considering wind speed correlation and un-correlation are developed, respectively. A reliability-based reserve expansion method...

Coordinated control of a DFIG-based wind-power generation system with SGSC under distorted grid voltage conditions

DEFF Research Database (Denmark)

Yao, Jun; Li, Qing; Chen, Zhe

2013-01-01

in the multiple synchronous rotating reference frames. In order to counteract the adverse effects of the voltage harmonics upon the DFIG, the SGSC generates series compensation control voltages to keep the stator voltage sinusoidal and symmetrical, which allows the use of the conventional vector control strategy......This paper presents a coordinated control method for a doubly-fed induction generator (DFIG)-based wind-power generation system with a series grid-side converter (SGSC) under distorted grid voltage conditions. The detailed mathematical models of the DFIG system with SGSC are developed...

[Multimag-M magnetotherapy system of the new generation].

Science.gov (United States)

Borisov, A G; Grigor'ev, E M; Gurzhin, S G; Zhulev, V I; Kriakov, V G; Proshin, E M

2007-01-01

The Multimag-M microprocessor chronomagne-totherapy system of the new generation is described. The system provides on-line diagnosis of the pulse parameters and the breathing rate during a biotechnical feedback session. The requirements to the system software, as well as its specific features and design principles, are considered.

Consolidated nuclear steam generator

International Nuclear Information System (INIS)

Jabsen, F.S.; Schluderberg, D.C.; Paulson, A.E.

1978-01-01

An improved system of providing power has a unique generating means for nuclear reactors with a number of steam generators in the form of replaceable modular units of the expendable type to attain the optimum in effective and efficient vaporization of fluid during the generating power. The system is most adaptable to undrground power plants and marine usage

Optimal gravitational search algorithm for automatic generation control of interconnected power systems

Directory of Open Access Journals (Sweden)

Rabindra Kumar Sahu

2014-09-01

Full Text Available An attempt is made for the effective application of Gravitational Search Algorithm (GSA to optimize PI/PIDF controller parameters in Automatic Generation Control (AGC of interconnected power systems. Initially, comparison of several conventional objective functions reveals that ITAE yields better system performance. Then, the parameters of GSA technique are properly tuned and the GSA control parameters are proposed. The superiority of the proposed approach is demonstrated by comparing the results of some recently published techniques such as Differential Evolution (DE, Bacteria Foraging Optimization Algorithm (BFOA and Genetic Algorithm (GA. Additionally, sensitivity analysis is carried out that demonstrates the robustness of the optimized controller parameters to wide variations in operating loading condition and time constants of speed governor, turbine, tie-line power. Finally, the proposed approach is extended to a more realistic power system model by considering the physical constraints such as reheat turbine, Generation Rate Constraint (GRC and Governor Dead Band nonlinearity.

Coordinated control of wind generation and energy storage for power system frequency regulation

Science.gov (United States)

Baone, Chaitanya Ashok

Large-scale centralized synchronous generators have long been the primary actors in exercising active power and frequency control, and much of the existing grid control framework is predicated upon their dynamic terminal characteristics. Important among these characteristics is the inertia of such generators. These play key roles in determining the electromechanical stability of the electric power grid. Modern wind generator systems are partially or fully connected to the grid through power electronic interfaces, and hence do not present the same level of inertial coupling. The absence of inertial frequency response from modern wind generator systems is a topic of growing concern in power engineering practice, as the penetration of wind generation is expected to grow dramatically in the next few years. Solutions proposed in the literature have sought to address this problem by seeking to mimic the inherent inertial response characteristics of traditional synchronous generators via control loops added to wind generators. Recent literature has raised concerns regarding this approach, and the work here will further examine its shortcomings, motivating approaches that seek to optimally design for the characteristics of the equipment exercising the control, rather than forcing new technologies to mimic the characteristics of synchronous machines. In particular, this work will develop a new approach to power system frequency regulation, with features suited to distributed energy storage devices such as grid-scale batteries and wind turbine speed and blade pitch control. The dynamic characteristics of these new technologies are treated along with existing mechanisms, such as synchronous machine governor control, to develop a comprehensive multi-input control design approach. To make the method practically feasible for geographically distributed power systems, an observer-based distributed control design utilizing phasor measurement unit (PMU) signals along with local

Application of automated reasoning software: procedure generation system verifier

International Nuclear Information System (INIS)

Smith, D.E.; Seeman, S.E.

1984-09-01

An on-line, automated reasoning software system for verifying the actions of other software or human control systems has been developed. It was demonstrated by verifying the actions of an automated procedure generation system. The verifier uses an interactive theorem prover as its inference engine with the rules included as logic axioms. Operation of the verifier is generally transparent except when the verifier disagrees with the actions of the monitored software. Testing with an automated procedure generation system demonstrates the successful application of automated reasoning software for verification of logical actions in a diverse, redundant manner. A higher degree of confidence may be placed in the verified actions gathered by the combined system

Automated graphic image generation system for effective representation of infectious disease surveillance data.

Science.gov (United States)

Inoue, Masashi; Hasegawa, Shinsaku; Suyama, Akihiko; Meshitsuka, Shunsuke

2003-11-01

Infectious disease surveillance schemes have been established to detect infectious disease outbreak in the early stages, to identify the causative viral strains, and to rapidly assess related morbidity and mortality. To make a scheme function well, two things are required. Firstly, it must have sufficient sensitivity and be timely to guarantee as short a delay as possible from collection to redistribution of information. Secondly, it must provide a good representation of the results of the surveillance. To do this, we have developed a database system that can redistribute the information via the Internet. The feature of this system is to automatically generate the graphic images based on the numerical data stored in the database by using Hypertext Preprocessor (PHP) script and Graphics Drawing (GD) library. It dynamically displays the information as a map or bar chart as well as a numerical impression according to the real time demand of the users. This system will be a useful tool for medical personnel and researchers working on infectious disease problems and will save significant time in the redistribution of information.

Multi-Generation Concentrating Solar-Hydrogen Power System for Sustainable Rural Development

Energy Technology Data Exchange (ETDEWEB)

Krothapalli, A.; Greska, B.

2007-07-01

This paper describes an energy system that is designed to meet the demands of rural populations that currently have no access to grid-connected electricity. Besides electricity, it is well recognized that rural populations need at least a centralized refrigeration system for storage of medicines and other emergency supplies, as well as safe drinking water. Here we propose a district system that will employ a multi-generation concentrated solar power (CSP) system that will generate electricity and supply the heat needed for both absorption refrigeration and membrane distillation (MD) water purification. The electricity will be used to generate hydrogen through highly efficient water electrolysis and individual households can use the hydrogen for generating electricity, via affordable proton exchange membrane (PEM) fuel cells, and as a fuel for cooking. The multi-generation system is being developed such that its components will be easy to manufacture and maintain. As a result, these components will be less efficient than their typical counterparts but their low cost-to-efficiency ratio will allow for us to meet our installation cost goal of $1/Watt for the entire system. The objective of this paper is to introduce the system concept and discuss the system components that are currently under development. (auth)