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Life Cycle Cost(LCC) is being more and more widely applied in the procurement and management of power equipment, however, the failure cost in LCC of the equipment is difficult to forecast because of uncertainty during its operation. According to the characteristic that the cumulative failure probability observes the Weibull distribution model, a new referential method is put forward in this paper...
A method of reliability evaluation for complex medium-voltage distribution system based on feeder partition model and the minimal path method is proposed in this paper. According to the topology of distribution system, a distribution network is divided into different zones, and then the distribution network is changed into an oriented diagram. Applying the minimal path method, this diagram is divided...
Crack is a main destroyed formation of high-intensity mining. Based on measured data, the difference between cracks caused by high-intensity mining and other mining methods had been studied. Control cracks showed obviously when using high intensity mining, and often gone with many small cracks. They always showed as couple, and the ground between them appeared as horst or rift valley, which destroyed...
In the current power market environment of China, lease operation mode of pumped storage power station is an efficient way to realize static and dynamic benefits of power station, also it's one of main operation mode in China. A two-party profit model among pumped-storage power station and grid companies was build. The profits of power station and grid company were discussed to meet the individual...
As the fault of key components for shield machine caused great economic loss and harmful social effect, An on-line condition monitoring and fault diagnosis system was designed for large-scale engineering machine(shield machine). At first the paper described the object to build remote monitoring center, and then introduced in detail monitoring equipment by machine loaded which consisted of four parts,...
Global weather condition is deteriorating, and the impacts on the transmission and distribution system are more and more serious. Therefore it is especially important to take the reliability impact assessment of the grid considering the weather factors. This article will divide the weather state into normal weather, bad weather and catastrophic weather, and establish the power system reliability evaluation...
Now the available system which can detect the fault of wind turbine is meeting many problems, such as delay, limitations, and closure. The diagnostician and manufacturer can't communicate with the local wind farm in time; they can't share the wind turbine fault information; the system also can't predict the trend condition of the wind turbine. This paper proposes a kind of wind farm fault diagnosis...
Taking source-side maintenance as an example, the possibility of wide area control of smart substation was studied in this paper. Source-side maintenance IED which meets the IEC61850 standard was proposed. On the basis of analyzing the IED's logical model and information flow, the corresponding data IED object model is designed. The transmission principles of sampling data based on the publish subscribe...
Since 1997, Costanza and others assessed the value of global ecosystem services. The assessment methodology and the adaptability of the established methods have become the concern of academia. The paper assesses the four forest ecosystem services of Beibu Gulf in China, based on the services valuation methods, accepted by civil experts. These services include forest products, carbon sequestration...
To solve the water fouling problem in condenser tubes of small steam turbines, a continuous and automatic cleaning technology is proposed. It prevents and removes fouling by liquid solid fluidization with vibrating spiral inserts in tubes. This paper introduces the structure and explains the mechanism. The experimental results show that the self-cleaning ability meets the need for removing both soft...
Power transformer has degraded under its normal and abnormal operating conditions, maintenance activities are vital to restore the condition back to the normal condition. Even though the traditional preventive maintenance is well known and successfully performed, but the method had a high cost. Therefore, the objective of this paper is to improve the drawback by systematical record of the scattering...
R&D personnel competence level is the important force which determines the independent innovation ability in enterprises. On the basis of defining the connotation and characteristics of R&D personnel competence in enterprises, then based on the knowledge essence of competence, the paper reveals the enhancement mechanism of R&D personnel competence in enterprises from two levels of staff...
For environmental issues, the penetration of renewable distributed generations (DGs) will grow gradually in the future. It is a consensus that the emergence of DGs could improve the power supply reliability of distribution systems. However, this improvement is based on the output characteristics, operation manners as well as protection manners of DGs, which are new factors and not considered in traditional...
Two modes of rapid development platform are introduced briefly, and their deficiency are analyzed, a template-based framework for the rapid application development platform (RADP) is propose, and the various components of the framework are introduced, the advantages of the template framework and development prospects are summarized. At the last, the platform and common development methods are compared,...
The retrofit of flow passage of a steam turbine is a feasible measure of save energy and capacity enlargement of a unit and the ROI (return on investment) is high. The economics of retrofitted units is related to many factors. This paper analyzes the economic indicators of a 300WM steam turbine flow passage retrofit, as payback period, FNPV (Financial Net Present Value) and FIRR (financial Internal...
From the perspective of optimal LCC(Life cycle cost), this paper studied the method to develop a reasonable maintenance strategy of power equipment. The deterioration theory in the field of mechanical engineering was led in, based on that we analyzed the failure rates of each repair period and established the model of the optimal problem, then, through a case study, we got the optimal maintenance...
Optimal switching device placement is of vital importance for distribution networks' planning and operation. The combination of distributed generation (DG) and main networks is considered a principle way that could reduce investment outlay, lower the energy depletion and improve reliability of distribution systems. At present, all the study on DG impact on reliability of distribution systems is negative...
One of the trends concerning offshore wind farms is to increase the distance from the wind farm to the shore, and has to be transported over very long distances to make a connection with the main supply grid. But placing wind farms offshore rises a lot o challenges related to construction, installation and nevertheless with the energy transmission. VSC HVDC is a rather new technology with promising...
A hybrid approach based on the pseudo-sequential sampling and the network-equivalence techniques is proposed for distribution system reliability evaluation in this paper. In pseudo-sequential sampling, a failure state is obtained based on the non sequential simulation at first, then the whole system interruption I(a set of successive failure states) is acquired by the forward/backward simulation associated...
This paper presents a new approach to the fuzzy generation scheduling (GS) problem, considering reserve requirement, load-generation balance and wind power generation constraints. The modeling of constraints is an important issue in power system scheduling. These constraints are therefore "fuzzy" in nature, and crisp treatment of them may lead to over conservative solutions. In this paper,...
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