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This paper studies a real 36-MW large tubular hydro-generator to solve the transient variation problem of the loss and heat of damper bars during short circuit faults in tubular hydro-generators. The transient analysis method of electromagnetic-temperature fields is adopted to study the transient variation problem of the loss and heat of damper bars during three-phase symmetrical short-circuits, single-phase to ground asymmetrical short-circuits, and phase-to-phase asymmetrical short-circuits under rated operation states. The research work provides valuable findings for improving the level of state analysis, the design and manufacturing processes, and the operation and maintenance of large-scale tubular hydro-generators.

With the continuous development of the social economy, the urban residential structure is also changing, and people have higher and higher requirements for the living environment. Moreover, the landscape construction of public spaces in cities is an important part of the city. It is easy to neglect the comprehensive consideration of historical development and regional culture in architectural projects. The overall lack of individuality in urban design, the lack of characteristics of adapting measures to local conditions, and the blind emphasis on architectural landscaping have led to a serious lack of regional cultural characteristics and spiritual culture in public places. Therefore, in terms of the problems of insufficient landscape construction quality and green concepts being insufficient in the construction environment of cities, an evaluation method system is established in the paper to further study the shortcomings of the scenic area architecture. What is more, relying on the personal experience of the users in the scenic spot and understanding the real needs of the public space landscape environment around the scenic spot, scientific methods and a complete system are applied to make an overall assessment of the public space in the built residential area. Besides, according to the data analysis of the simulation experiment, the advantages and disadvantages of the public space in the residential area are extracted. Combined with the current research status, the green concept design strategy of the public space landscape environment in the scenic spot is summarized. Lastly, according to the data analysis of the simulation experiment, the evaluation satisfaction of the activity atmosphere, plant configuration, and overall layout is improved by 4.2%, 3.7%, and 3.1% compared with other methods, which proves that this study has a more reasonable planning program to meet the various needs of public open space. The development of urban landscape design provides a valuable reference.

Techno-economic optimization of a standalone solar/wind/battery hybrid system located in Xining, China, is the focus of this paper, and reliable and economic indicators are simultaneously employed to address the problem. To obtain a more precise Pareto set, a novel multi-objective differential evolution algorithm is proposed, where differential evolution with a parameter-adaptive mechanism is applied in the decomposition framework. The algorithm effectiveness is verified by performance comparisons on the benchmark test problems with two reference algorithms: a non-dominated sorting genetic algorithm and a multi-objective evolution algorithm based on decomposition. The applicability of the proposed algorithm for the capacity-optimization problem is also validated by comparisons with the same reference algorithms above, where the true Pareto set of the problem is approximated by combining of the three algorithms through the non-dominant relationship. The results show the proposed algorithm has the lowest inverted generational distance indicator and provides 85% of the true Pareto set. Analyses of the Pareto frontier show that it can produce significant economic benefits by reducing reliability requirements appropriately when loss of power supply probability is less than 0.5%. Furthermore, sensitivity analyses of the initial capital of wind turbine, photovoltaic panel and battery system are performed, and the results show that photovoltaic panel’s initial capital has the greatest impact on levelized cost of electricity, while the initial capital of wind turbine has the least impact.

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The LiAl is a typical intermetallic compound which has many important applications. We have employed the first-principles pseudopotentials and the plane wave energy band method to calculate the vacancy formation energies of Li and Al vacancies in LiAl intermetallic compound as well as the atomic relaxations around the vacancies. The charge redistribution around the vacancies, electronic densi ty of states and their band structures are also discussed.

In 2010, State Grid Corporation put forward the safety efficiency cost (SEC) index system, this index can be used in equipment management, scheme selection and other fields [1]. This paper combines the original SEC index with the characteristics of sequence control to form a set of SEC index which apply to the sequence control transformation. In order to make more accurate decision on the transformation, this paper establishes a set of three-dimensional decision model which is suitable for the transformation of sequence control. This model compares the index data of transformation time, location and mode to get the best transformation plan. To prove the feasibility of the SEC index and the three-dimensional model, the paper makes the IEEE 24 buses network as an application scenarios for the sequence control transformation, and use the SEC index to make a decision on the transformation time, place and method, then finally obtained a reasonable scheme of sequence control transformation.