China has rich solar energy sources. Two-thirds of its land have more than 2200 hours annual sunshine time, and the annual received solar radiation in land surface, which is about 3340-8400 MJ/m 2 , is equivalent to 1...
详细信息
China has rich solar energy sources. Two-thirds of its land have more than 2200 hours annual sunshine time, and the annual received solar radiation in land surface, which is about 3340-8400 MJ/m 2 , is equivalent to 1.7 trillion tons of standard coal. This paper first introduces the distribution of solar energy resources in China and then analyzes the present situation of research and development of China's solar energy, and evaluates the new PV technologies and challenges in China. In final, the development of new PV technologies in China is discussed.
This article introduces the project's background of the transmission line icing thickness regelation. Through analyzing characteristics of transmission line scene pictures, there are two main technical difficultie...
详细信息
ISBN:
(纸本)9781612848792
This article introduces the project's background of the transmission line icing thickness regelation. Through analyzing characteristics of transmission line scene pictures, there are two main technical difficulties. The lower edge of the wire is in shadow and the complex background of the wire, respectively, which are encountered in the scene image pre-processing. This article proposes using a common method, such as threshold segmentation for grayscale images, and using a gradient operator for the edge extraction on the transmission line icing image. We use a line-search algorithm to calculate the value of the thickness of transmission line ice covering. We use several tests applied to many images on different complex backgrounds to prove the algorithm is effective.
This paper presents a practical approach to implement the economic dispatch of the hydrothermal power system in Southern China. The proposed economic dispatch method first computes the initial generation plans for all...
详细信息
ISBN:
(纸本)9781424462537
This paper presents a practical approach to implement the economic dispatch of the hydrothermal power system in Southern China. The proposed economic dispatch method first computes the initial generation plans for all generator units including hydro units, which are determined according to the equal incremental principal of hydrothermal system. The system loss is approximately considered during the calculation of the initial generation plan. Then, the mathematical model of the optimal dispatch, which considers the network loss and security constraints, is set up based on the initial operation point. The solution algorithm is the modified interior point method. For showing the effectiveness of the proposed approach, the practical hydrothermal power system in southern China is used for demonstration. The results show the feasibility of the proposed dispatch method.
This paper presents an approach to analyze the steady-state voltage change in distributed network with or without connection of Photovoltaic (PV) plant. Several scenarios are discussed: the voltage drop of distributio...
This paper presents an approach to analyze the steady-state voltage change in distributed network with or without connection of Photovoltaic (PV) plant. Several scenarios are discussed: the voltage drop of distribution feeders with or without PV plant; the voltage impact in distributed network with different weather conditions; the impacts of PV power plant capacity on the voltage. A practical distribution system with PV plant in China is used for simulation. The results and analysis are reported.
After DGs are joined in the distribution network,a series of protection problem is brought out. The cooperation of now current protection,un-conspicuous fault character at DG and problem of drop-fuse are analyzed in t...
详细信息
ISBN:
(纸本)9781457700668
After DGs are joined in the distribution network,a series of protection problem is brought out. The cooperation of now current protection,un-conspicuous fault character at DG and problem of drop-fuse are analyzed in the paper. In order to cope with the protection problems,the protection key is indicated in the paper. Protection configuration with communication and protection configuration without communication are presented in the paper. As a result,the fiber direction protection and the intellectualized feeder protection suit to the distribution network with DGs.
After DGs are joined in the distribution network, a series of protection problem is brought out. The cooperation of now current protection, un-conspicuous fault character at DG and problem of drop-fuse are analyzed in...
详细信息
We discussed the optimal spare analysis for high-voltage-direct-current (HVDC) transmission system considering economy and reliability. Considering the capital, maintenance and the costumer interruption costs, we prop...
详细信息
We discussed the optimal spare analysis for high-voltage-direct-current (HVDC) transmission system considering economy and reliability. Considering the capital, maintenance and the costumer interruption costs, we proposed an optimal model for spare components in HVDC based on the minimum cost. An enumeration-analytical method was proposed to solve this model based on the fact that there are usually only a few spare components in practical HVDC projects. A single 12-pulse winding HVDC transmission system was used for case studies. The spare analysis of AC filter, transformer, thyristor and smooth reactor were studied using cost-benefit method. The results show that the proposed model and calculation procedure can be applied to practical HVDC transmission systems in planning and design processes.
Weak parts of a HVDC transmission system can be recognized using sensitivity analysis, which has been an important technique for system reliability assessment and enhancement. A new sensitivity analysis method for HVD...
详细信息
Based on finite element method and the asymptotic boundary condition, the paper presents a new calculation method for unbounded field problem with complex parts by the domain-decomposition and iterative processes. Fir...
详细信息
In the field of electrical power engineering, pattern recognition is commonly used for classification of defects caused of Partial Discharge (PD) in Gas Insulated Substation (GIS) in order to assess the insulated syst...
详细信息
暂无评论