Large-scale water conservancy and hydropower project is such open systems: large investment、long cycle, the internal structure is complex and the systems involve many complex factors. There are the many factors who have impacts on system , and all the factors have the complex relationship between each other.The risk which the project faces is very complex, so the manager should control risk in time and analysis the reason of the risk.Many scholars have carry out much research about the project risk analysis approach, and presentrd variety of risk analysis methods. But these methods have their own inherent defects, even fuzzy synthetic discrimination which have been recognized and wide used, have ite shortcomings.Large-scale water conservancy and hydropower project is an important infrastructure, but there is not a complete evaluation model about it, and give a orbicular risk analysis method.For more information please login in…
provides the production and delivery of electrical power (electrical energy), often known as power, or electricity.
...electrical power.device or system that supplies electrical or other types of energy to an output load or group of loads.
...a field of engineering that deals with the study and application of electricity, electronics and electromagnetism
...Power transmission is the movement of energy from its place of generation to a location where it is applied to performing useful work.
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From the data collected by Lightning Location System, we can find that Chongqing is strong -lightning-day and has about 95 lightning days per year and has 7.022 hours per lighting day. In addition to the ground flashing density is 0.1216/km2·d and beyond the value of rules. So according as the fact of Chongqing power system,the paper will investigates the 110kV power transmission line becau...
Insulator leakage current is closely related to the development process of flashover discharge,can comprehensively reflect the degree of contamination, humidity level, under-voltage of insulatorand insulator shape, and so on. Therefore, predicting the change of insulator leakage current value isof great significance for the power system increasing the ability of flashover prevention.This pape...
The neutral indirectly grounded power distribution system under 35 kV has widely used in our country. The internal over-voltage frequently occurs in the system and lots of faults have been caused. So, it is practically important to analyze the principles and the causes of the internal over-voltage in power distribution system and to find ways to eliminate it. This paper analyzes various kinds...
The requirement for the reliability of electric power supply in electric power system is ever-increasingly high with the improvement of rated voltage. The loss incurred by unreliable equipment insulation far exceeds the value of electrical equipment, but the insulation test is an important method to demonstrate whether high-voltage electric equipment can run reliably and safely on site. There...
Ozone,which be used extensively, has been a kind of ideal green resource because of it\\\’s oxidization. In numerous ozone synthesize methods, dielectric barrier discharge has become the main method in large-scale industry ozone synthesis. On the foundation of the foregone work, the paper improved the structure of ozonizer and the power supply. Meanwhile, I have developed a device of det...
The application of power cable in the power supplies is getting increased and the reliability of the supplied power quality is becoming an important concern of power providers and consumers. Thus the reliability of power cable is one of the most important factors which guarantee the reliable power supply.But how to realize the online monitoring and repairing of power cable? One of the importa...
The aim of this paper is to design a kind of lightning-proof gap, which can be fixed atthe two side of insulator chain. When lightning stroke happened in transmission line, thegap could lead the lightning current to earth therefore the insulation chain was notdestroyed by flashover. Working with the auto-reclose circuit breaker, it can maintainthe operation of transmission line. The main conte...
Lightning, inductive load switching and ESD are sources of transient voltage that can gain entry into sensitive electronic equipment and system, burn off the semiconductor devices and so cause damages to the whole system. Transient voltage suppressor (TVS) is widely applied to protect circuit and system as it can substitute the traditional gas discharge tubes (GDTs)、metal oxide varistors (M...
On the basis of compare virtue and defect for existed discriminances, this paper elicited calculational expression of the open phase terminal voltage and calculated the frequency for current and voltage of the phase that is switched off with shunt compensators, and criterions to determine temporary fault and permanent fault is proposed. A integrated criterion based on the amplitude relationsh...
Indirectly grounded power system is widely used in medial and low voltage distribution networks in the world (including the neutral point is not grounded, by the Petersen-coil or by high resistors), which is benefit to improve the reliability of power system, because its characters that fault current is low and the system can continue to provide power to load while single-phase ground fault o...