981 resultados para Electric power - Protection


Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this work the problem of defects location in power systems is formulated through a binary linear programming (BLP) model based on alarms historical database of control and protection devices from the system control center, sets theory of minimal coverage (AI) and protection philosophy adopted by the electric utility. In this model, circuit breaker operations are compared to their expected states in a strictly mathematical manner. For solving this BLP problem, which presents a great number of decision variables, a dedicated Genetic Algorithm (GA), is proposed. Control parameters of the GA, such as crossing over and mutation rates, population size, iterations number and population diversification, are calibrated in order to obtain efficiency and robustness. Results for a test system found in literature, are presented and discussed. © 2004 IEEE.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Grant no. R-800700.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Cover-title.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Summary: On June 22, 2001, the groundwork was laid for the construction of new electric generation in the state of Illinois when the Illinois Resource Development and Energy Act was signed. Overwhelmingly approved by the Illinois General Assembly, this broad-based $3.5 billion package is designed to reinvigorate the Illinois coal industry and to strengthen the state's ability to provide electricity to its citizens. The legislation (Public Act 92-0012) provides tax incentives and financial assistance to builders of new electric plants generating in excess of 400 megawatts that create Illinois coal-mining jobs, new and expanding coal mines, and natural gas-fired baseload electric plants with a capacity of 1,000 megawatts. The legislation also directs the the Illinois Environmental Protection Agency to explore the need for a state-level, multi-pollutant strategy to reduce emissions from coal-fired electric generating plants.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Power system policies are broadly on track to escalate the use of renewable energy resources in electric power generation. Integration of dispersed generation to the utility network not only intensifies the benefits of renewable generation but also introduces further advantages such as power quality enhancement and freedom of power generation for the consumers. However, issues arise from the integration of distributed generators to the existing utility grid are as significant as its benefits. The issues are aggravated as the number of grid-connected distributed generators increases. Therefore, power quality demands become stricter to ensure a safe and proper advancement towards the emerging smart grid. In this regard, system protection is the area that is highly affected as the grid-connected distributed generation share in electricity generation increases. Islanding detection, amongst all protection issues, is the most important concern for a power system with high penetration of distributed sources. Islanding occurs when a portion of the distribution network which includes one or more distributed generation units and local loads is disconnected from the remaining portion of the grid. Upon formation of a power island, it remains energized due to the presence of one or more distributed sources. This thesis introduces a new islanding detection technique based on an enhanced multi-layer scheme that shows superior performance over the existing techniques. It provides improved solutions for safety and protection of power systems and distributed sources that are capable of operating in grid-connected mode. The proposed active method offers negligible non-detection zone. It is applicable to micro-grids with a number of distributed generation sources without sacrificing the dynamic response of the system. In addition, the information obtained from the proposed scheme allows for smooth transition to stand-alone operation if required. The proposed technique paves the path towards a comprehensive protection solution for future power networks. The proposed method is converter-resident and all power conversion systems that are operating based on power electronics converters can benefit from this method. The theoretical analysis is presented, and extensive simulation results confirm the validity of the analytical work.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This paper discusses the effects of thyristor controlled series compensator (TCSC), a series FACTS controller, on the transient stability of a power system. Trajectory sensitivity analysis (TSA) has been used to measure the transient stability condition of the system. The TCSC is modeled by a variable capacitor, the value of which changes with the firing angle. It is shown that TSA can be used in the design of the controller. The optimal locations of the TCSC-controller for different fault conditions can also be identified with the help of TSA. The paper depicts the advantage of the use of TCSC with a suitable controller over fixed capacitor operation.