Advanced Materials Research Vols. 614-615

Abstract: The risk assessment incorporate the severity as well as the possibility of event, however synthetic severity index weight coefficient is setting up subjectively in existing catastrophic event risk assessment. To overcome the uncertainty of the weight setting in conventional synthetic risk assessment, this paper introduces the entropy method to determine the weight objectively. Based on the existing severity measure matrix, the weight coefficient of severity indicator is generated by the entropy weight method combined with fuzzy membership function, furthermore proposing a catastrophic event assessment mathematical model and method based on uncertainty. The simulation of the local power grid proved that the proposed method is with correctness and objectivity, provided with engineering value.

Abstract: As the power quality problem has become the world focus, DFACTS devices which are used to improve the power quality problems in distribution system are widely used in power system. Every typical DFACTS equipment were reviewed, including the APF, DSTATCOM, DVR, SSTS and so on, their function and advantages were compared and summarized in this paper. Finally, some test cases were carried out in the PSCAD / EMTDC environment to simulate their effects, and then the future of their development was discussed.

Abstract: In this paper, MAS is used to model the framework of smart grid. Multi-Agent Systems (MAS) is one of the popular method in Distributed Artificial Intelligence (DAI) in the past years, which is a good tools to simulate and model the complex systems. Several MAS develop platforms are exist. Considering that JADE (Java Agent Development Framework) is one of the helpful and convenient developing environments of MAS, JADE is adapted to develop smart grid control framework. In this paper, a suitable frame construction of the Multi-Agent Systems for the current power system is designed, which is applied to the smart grid with excellent adaptability and flexibility.

Abstract: Short Term Load Forecasting is important to power system. It can be economic and reasonable to arrange start and stop of the Generator in wire net, The text adopt radial basis function neural networks. The GA-optimized multi-core radial basis function SVM is applied to extract useful data and short-term load forecasting accuracy based on RBF neural network has been improved. In this paper, The advantages of improving the algorithm is demonstrated by the application of the MATLAB simulation with the input data of the spring load collected from California, United States.

Abstract: With the increasing of the capacity of grid-connected photovoltaic (PV) power system, islanding detection becomes more prominent and significant. At present, islanding detection methods used in grid-connected photovoltaic system can be divided into passive detection methods and active detection methods these two categories, which can also be divided into a variety of methods. This paper shows a comprehensive review of islanding detection methods, classifies the methods of islanding detection, analyzes the principles and characteristics of various islanding detection methods, indicates their appropriate situations, and pointes out the prospect of islanding detection methods. In practical applications, according to the actual situation, selects one or more islanding detection methods can attain better detection effect.

Abstract: The distributed generation(DG) location, capacity and its influence to distribution network is an important research subject of smart grid. According to the typical daily load curve change rule in distribution network, selecting two operation modes of weighted largest load and weighted least load, taking the minimum of reverse flow times and network loss for the target, combined with the type of DG and operation characteristics , confirming optimal accessing points and optimal capacity of DG. Through the comparative study, the rational introduction of DG improves the voltage level of distribution network and reduces the network loss.

Abstract: This paper compares of the energy storage system in power system, analysis of superconducting magnetic energy storage advantage. Reviewing the superconducting magnetic energy storage ( SMES ) equipment adopted the power electric technology general structure and principle, discussing the key of voltage source and current source converter details.

Abstract: As a crucial constituent in tri-generation application, electric energy storage and power system plays an important role regarding efficient utilization of electrical energy in tri-generation. This paper presents the results showing that the optimization of electrical energy storage is able to promote the performance of tri-generation. Initial investigation, including laboratory tests and computational simulation using Dymola software, have been carried out. A case study exemplifies how diverse hybrid systems accommodate domestic power demands. The outcomes validate that the hybrid electric system consisting of generator, batteries and super capacitor can satisfy the electricity requirements for the household. it is also found that the hybrid system can supply the peak electricity demands where the integration of super capacitor can alleviate the overcharge of batteries in this application.

Abstract: An approach to measure the positive sequence parameters of transmission lines based on harmonic method is introduced. The mathematical model and measurement procedure of the new method are explained in detail. The hardware structure of the measuring system based on GPS is given. The simulation results show that the new method can satisfactorily meet the need of measuring the positive sequence parameters of transmission lines under strong interference condition.

Abstract: It is meaningful to import protection modeling and simulation into power system simulation for analyzing dynamic operation or cascaded operation of protection when there is a disturbance in power system. Based on the former researches of protection modeling method and protection simulation system, an application of the protection modeling and simulation mentioned above in transformer inrush eliminating algorithm research is explicated for proving the feasibility and validity of them in novel protection algorithm research in this short paper.