HITACHI is engaged in a variety of social infrastructure businesses, including those in the fields of thermal and nuclearpower generation, electricpower distribution, and renewable energy. These businesses operate primarily through PowerSystems Company of Hitachi, Ltd. Global electricpower generation is predicted to grow strongly, reaching about 1.7 times 2008 levels by 2030 (see Fig. 1). With extensive construction of new coal-fired thermal power plants planned for regions such as Eastern Europe and Asia, as well as the replacement of aging plants in Europe and the USA, demand is forecast to remain strong. Meanwhile, many nations, including the UK and the Republic of Lithuania, are continuing with plans for nuclearpower plants, even after the Great East Japan Earthquake. Also, installation of renewable energy is accelerating around the world, and the market for electricpower transmission and distribution is expected to expand, particularly in emerging economies.
The thermodynamic efficiency of the a nuclearpower generating system increases in pro- portion to the nominal operating thermal power of the reactor core. This nominal amount of thermal power, in turn, determines the amount of electrical power that is output by the electrical generator. Thus, in order to improve thermodynamic efficiency, the electrical power output of a single NPP unit is usually rather large, ranging from hundreds to thou- sands of megawatts electric (MWe). Large amounts of energy therefore flow between, and are stored throughout, the subsystems of an NPP. These large amounts of energy increase the potential for accidents involving uncontrolled releases of energy to occur. In addition, NPPs utilize a radioactive primary fuel source that, if affected, may significantly increase the severity of such accidents. NPP designs therefore undergo continual enhancement to include measures that aid in preventing and mitigating the consequences of severe acci- dents, i.e. accidents that involve significant core degradation. These enhanced measures aim to protect workers, the public, and the environment from the harmful effects of the ionizing radiation that is produced as a result of fission reactions and is to be contained during a severe accident . The development of these enhanced measures is essential in reducing the likelihood of future severe accidents like those that have occurred at Three Mile Island NPP Unit 2 in 1979, Chernobyl NPP Unit 4 in 1986, and Fukushima Daiichi NPP Units 1, 2, 3, and 4 in 2011.
Electricpower can be generated by conventional thermal power plants (using fossil fuels, or nuclear energy), hydro power stations and other alternative power generating units (such as wind turbine generators, photovoltaic arrays, fuel cells, biomass power plants, geo thermal power stations etc.,).Fossil fuels (including coal, oil and natural gas) and nuclear energy are not renewable, and their resources are limited. These renewable/alternative power generation systems normally have modular structure and can be installed close to load centers as distributed generation sources (except large wind and PV farms). Therefore no high voltage transmission lines are needed for them to supply.
History has shown that accidents and their precursors at commercial nuclearelectric generating stations result from a series of decisions and actions that reflect flaws in the shared assumptions, values, and beliefs of the operating organization. For example, the Three Mile Island accident involved flawed assumptions about the importance of preventing the pressurizer from completely filling, resulting in operators shutting off safety injection pumps needed for core cooling. The Chernobyl accident involved a lack of appreciation for the unique aspects of nuclear technology (particularly reactivity control) and of the importance of operating the plant in accordance with its design basis and operating procedures, resulting in decisions to disable important safety systems to perform a special test. At Davis-Besse NuclearPower Station, a flawed assumption that dry boric acid would not corrode the reactor vessel head contributed to wastage of the head material.
The economic costs of public ownership and monopolistic market structures became more and more apparent. In the 1970s, the United States began to experiment with power sector reform. By the 1980s, policy makers in Europe, the Americas and elsewhere realized that electricity, natural gas and telecommunications were no longer monopolies. Thanks to advances in technology, economic theory, and increasingly sophisticated regulatory instruments, it became feasible to introduce competition with the same effect as in other industries. Substantial improvements in operational and investment efficiency, the reduction of costs to end-users, an improvement of services, and a higher rate of innovation thus became possible. During the 1990s, electricity and natural gas sectors have been transformed through the overhaul of regulatory frameworks, the introduction of competition, and increasing private participation. These policy reforms have been implemented in developed and developing countries alike.
Matrix equations of the elements of the EPS and the whole system were com- piled on the basis of the most widely obtained equations of state variables   , which are small deviations of the mode parameters—the angles of the rotor load of the synchronous generator, busbar voltages, power and other operating parameters of the EPS. The considered matrix equations are used for analysis of transient processes and steady-state stability of EPS and for the synthesis of op- timal parameters of regulators of synchronous machines operating in an elec- trical system.
Tubular conductors offer minimum skin-effect compared to other commonly used conductor shapes with the same cross-sectional area , . With a proper design in terms of minimum proximity effect losses, a tubular conductor might be adopted as an optimal type of the conductor for wireless power transfer (WPT) resonator coils. To bring an experimental design closer to practice, the important problem of resonator coil optimal design needs to be solved. In other words, for specified geometrical constraints in terms of limited winding space, and for a specified operating frequency, an optimal coil structure should be derived. As stated below, Litz-wire based resonant coils can easily inherit models and optimization procedures from multi-turn, multi-layer, high-frequency inductors and transformers. However, according to the author’s best knowledge, a mathematical model that describes the ac resistance of a multi-layer coil built from hollow tube conductors does not exist. As will be explained later in the text, most of the theoretical work related to copper tubular conductors published so far deals with a single conductor, or multiple conductors (typically two or three) arranged in some particular formation. The final results are mostly given in a graphical or tabular form inconvenient for further manipulations.
The most important function of a recent electricpower system is to provide electricpower to its customers at the lowest possible cost with acceptable reliability levels. The two aspects of economics and reliability often conflict and present power system managers, planners, designers and operators face with a wide range of challenging problems. The price that a customer is willing to pay for higher reliability is directly connected to the interruption costs created by power failures. Some customers may be willing to pay more to receive higher reliability and others may be willing to pay less for lower reliability. Utilities may also be willing to provide higher reliability of power supply at no increased customer cost because of competition. Decision-making depends on many aspects such as social, economic, environmental and government considerations etc. and is a difficult task. System customer interruption cost analysis provides the opportunity to incorporate cost analysis and quantitative reliability assessment into a common structured framework, which can assist the decision making process. The highest level of efficiency can only be reached by comparing the increase of performance with the required investment costs. The assessment of expected performance indicators in respect to supply reliability is the task of the reliability assessment. This task can be divided into the calculation of non-monetary interruption indices and the calculation of reliability cost/worth indices. The calculation of non-monetary interruption statistics is more established [1-6]. One possible way to accommodate for customer importance is to use the costs for the energy not supplied (money/kWh) and/or a cost per interrupted power
However, while an increasing number of nuclear reactors are expected to resume their operational status, a debate about the necessity of nuclearpower and its role in Japanese energy policy is still vivid. Despite the widely-spread belief that the victims of the 3/11 disaster are strongly against nuclearpower plants due to the tragic experience, it in fact remains unknown what are those people’s attitudes and opinions, and how they are constructed. This paper aims to present the opinions on nuclearpower plants among the selected part of Japanese population who was affected by the 3/11 disaster, and examine the emotional and cognitive components which shape those opinions. In order to verify which of them, if any, are dominant, the dual-process theory is applied. This is a theory developed in social psychology within the last few decades which explains how human perception is constructed and what processes are involved in the attitude formation. Roots of the theory may be traced back to the views of such influential philosophers like Descartes, Kant or Hegel. In the 20th century they were adopted and rethought by psychologists which, resulted in lively debates between empiricists, behaviorists, pragmatists and representatives of Gestalt school of psychology 10 .
The first step in the development of the hot water con- sumption generator was to acquire knowledge of hot water consumption patterns of households in the controlled area. To achieve this objective, a telephone survey was con- ducted on 1000 randomly selected households across Tas- mania. It recorded demographic data (e.g. number of usual residents, combined income etc.) and details of hot water usages (e.g. average number of showers per day, average shower length etc.) of the surveyed households. This sur- vey focused on two peak periods in the Tasmanian power distribution network, i.e. morning and evening peaks from 6 am to 10 am and from 5 pm to 8 pm, respect- ively. Figures 2 and 3 show major results of the sur- vey. Figure 2 suggests a positive correlation between the average number of showers and the family size, in the morning and evening peaks. An unexpected drop in the average number of morning showers in house- holds with six or more residents can be explained by a relatively small sample size of this household type (just 2.3% of the total surveyed households).
In most of the industries grinding is the final stage in manufacturing process, there is no any further process. Grinding is a machining process which uses an abrasive wheel or belt type cutting tool. This grinding machine is used in various industries for finishing of work pieces and give high surface quality. Grinding with wheel or belt type cutting tool is used for different precision applications such as deburring in foundries and constructions, polishing, engraving and cut-off grinding. This paper highlights on recent development by using various power tools such as electricpower tools & pneumatic power tools also by implementing robotic systems.
Like the vast majority of security decisions, prioritization decisions are made in a non- cooperative environment, in which two competitors, an involved decision maker (here- after called the defender) and a potential attacker, seek to maximize their own benefits, each from a certain space of possible actions or strategies. To address this fact, our methodology leverages game theory principles to model the strategic behaviour of the involved players and to advise the defender on the best response to potential compro- mise plans. Generally, remote attackers seek to exploit cyber vulnerabilities present in IT networks to obtain unauthorized access to interconnected OT networks, thereby caus- ing significant damages. Due to their crucial role in our modern society, extreme (failure) events in power grids can be associated with irreversible consequences to the public health, safety, and security. Thus, the defender of such systems tends to boost the sys- tem resilience through avoiding situations in which high-level risks are more likely to happen. In a recent study on the power system resilience, Bie et al. stress the vital impor- tance of being able to mitigate (high-level) extreme risks as a condition for having resilient electricity infrastructures (Bie et al. 2017). To the best of our knowledge, this specific risk attitude imposed by the criticality of electricpowersystems is not well-addressed in existing prioritization approaches. Therefore, the presented game-theoretical model accounts for the aforementioned risk attitude by relying on a stochastic (tail) order reflecting the desired preference relation between the uncertain risk assessments. It is worth mentioning that traditional game-theoretical models, in which an expected utility (loss) optimization paradigm (Von Neumann and Morgenstern 2007) is overwhelmingly pursued, are not compatible with the comprehensive nature of our risk assessments. Tra- ditional models rely on scalar-valued payoffs, while our TTC-based risk assessments are distribution-valued.
Abstract: Higher power move in a wide interconnected system prompts genuine, security need in power framework tasks additionally if an abrupt blame happens there is an adjustment in voltage profile which can prompt an unexpected harm on burden end. These voltage hangs are remunerated at generator side by different strategies yet at the heap end there is a possibility. to maintain a strategic distance from such list at burden side a tangle lab show is proposed in which a transmission line is nourished with two sources out of which one is a breeze source and after that is exposed to a 3 stage blame. the voltage hang which happens is repaid in the other model at same moment when DVR Dynamic voltage restorer is modified and is associated at the midpoint of lattice. The outcomes acquired demonstrates that the voltage is redressed and profile is adjusted, DVR utilizes the vitality source in all around planned way and infuses vital AC voltage to framework.
In essence, Planning Table is a prediction tool that takes the scheduled production from the market, and subtracts a 5- minute granularity demand (load) forecasts to calculate the upcoming imbalance. Unfortunately, the quality of the fore- cast provided by Planning Table is limited. Arguably, this is because it relies greatly on the assumptions that the mar- ket is in balance on an hourly granularity, that the gener- ators produce the power without deviations from the plan, and that the demand prediction is accurate. This lack of an effective tool for forecasting upcoming market imbalances makes it hard to proactively manage imbalances with man- ual reserves, which in turn makes more use of the expensive and limited aFRR and FCR. As a result, it becomes difficult for the TSO reaching their KPI (Key Performance Indica- tor) in terms of frequency quality (i.e. minutes of frequency deviations in the past years) and experience increasing costs of balancing (Statnett et al. 2016). This, coupled with the fact that published literature on forecasting system imbal- ance volumes is very limited, indicates great room for im- provement (Klæboe, Eriksrud, and Fleten 2015), and is the main motivation behind this research.
Load Frequency Control (LFC) is an important function in modern Energy Management Systems. The successful oper- ation of interconnected power system requires the matching of total generation with total load demand and associated system losses. As the demand deviates from its nominal value with an unpredictable small amount, the operating point of power system changes, and hence, system may experience deviations in nominal system frequency and scheduled power exchanges. The main tasks of load frequency control are to hold system frequency at or very close to a specified nominal value and to maintain the correct value of interchange power between control areas (Singh Parmar et al., 2012). In real situations, the powersystems consist of conventional forms of electrical power generations like, thermal, hydro, and nuclear as a major share of electrical power. The configuration of today's integrated power system becomes more complex due to these power plants with widely varying dynamic characteristics. Nuclear units owing to their high efficiency are usually kept at base load close to their maximum output with no participation in system Load Frequency Control (LFC). But with integration of nuclearpower plants in the power system, it is also required
Abstract. The paper presents a method developed for detecting rough errors in the measurements related to batteries in the part of electricpower system that is characterised by low data redundancy. Since batteries either produce or consume power, not all methods of bad data detection can be used to detect erroneous measurements of the active power of the battery in the case of low measurement redundancy. Because of different values of the active power that a battery may produce or consume at several snapshots in row, dynamic algorithms cannot be used. In this study, a new method of bad data detection is developed. The method is based on the battery control strategy analysis.
COG has been used in teaching since 1996 at University of Lille and engineering schools of Lille (Arts et Métiers ParisTech (ex ENSAM),, Ecole Centrale and Polytech'Lille). EMR has been introduced in 2002 in the common Master degree of these university establishments. Both graphical tools are used in some other French universities and also at University of Québec Trois Rivières (Canada) since 2004, Ecole Polytechnique Fédérale de Lausanne (Switzerland) since 2005 and University of Tsinghua (China) since 2008. Indeed these graphical descriptions enable a unified way for causal description of the components of electromechanical systems. Moreover simple inversion rules lead to easily deduce the control structure of the studied system. It is then a very useful intermediary step for students to develop control of electrical drives.
The Earth has an abundance of renewable energy sources, including solar, wind, geo-thermal, hydro, and ocean waves. Large-scale utilization of distributed renewable energy resources would significantly improve U.S. energy security and independence, as well as global environmental health. In the FREEDM Systems vision, residential users will take charge of their energy needs with innovative solar panels, wind turbines, and electric/hydrogen fuel cell vehicles. Other new technologies, unforeseen today, will emerge as a result of the massive innovation fostered by the paradigm shift advocated by the FREEDM Systems ERC. Residential and commercial customers will sell or store excess power generated by their solar, wind, or fuel cell energy sources back to the power companies, reducing the demand for new oil- or coal-fired power generation plants, and decreasing green-house gas emissions.