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This presentation investigates Chinese standards for power system security and the practices in the relevant three-defense-lines. It also proposes an adaptive space-time cooperative framework for defending power system blackouts. Its essentials are: (1) acquisition and integration of wide area measurements from RTUs, PMUs, fault recorders and protection systems; (2) trajectory-based data mining and...
Modern wide area measurement systems began with the advent of GPS synchronized phasor measurement units in mid 1990s. Before the advent of these units, wide area measurements were in use in most power systems to achieve tie-line-bias control and automatic generation control. The blackout of 1965 in northeast America brought about the development of Energy Management Systems, which also depended upon...
In the most developed countries, Electric Power Engineering no longer attracts students as it used to, for the profit of Telecommunication and data processing disciplines. It is not the case for developing countries, but the common feeling is that Electricity is a mature technique, with no real expectation of technical development. Everything has already been invented or discovered! Hence, the question:...
Since the birth of the transistor in 1947 semiconductor technology has seen a rapid rate of development, leading to a vast diversity of applications. Today's integrated circuits can now contain up to a billion transistors and provide the fuel for the Digital Information Age which so seamlessly affects all of our lives and touches billions of people on our planet. Today's technology is “embedded” or...
Certain transmission corridors around the world are being forced to carry more power than they were originally designed to carry. These difficulties, coupled with a steady increase in load demands, have forced electric power systems into being operated with technical difficulties such as degraded reliability, degraded security, and degraded power quality. In addition, such factors as increasing numbers...
Future of our world greatly depends on access to energy and especially electricity. Tremendous challenges loom ahead for the Electricity Supply Industry, in almost all parts of the world and electrical engineering is to play a leading part in the answer. Be sure that there is a bright future for this discipline.
This paper introduces the concept of life cycle cost (LCC) in detail, offer an economy evaluation method for planning and design of HVDC by using Life Cycle Cost (LCC) is proposed, to find the converging points of the economy and reliability. The life cycle cost was considered from the very beginning of designing and bidding period. The influence of different model of HVDC on the operation, maintenance,...
This paper develops a novel hybrid intelligent method, which is combined Petri Net (PN) model with Ant Colony Optimization (ACO) to solve target network reconfiguration strategy for power system restoration. The target network is firstly modeled by Petri Net (PN) theory. In order to find the shortest restored energized path effectively, the transition rules of PN and the ACO algorithm are integrated...
In China, when an interconnected grid is subjected to large disturbances and becomes out-of-step, splitting the out of step area from the main grid has been used widely as the last resort for preventing widespread blackout. If an area that will be split from the main grid has large generation deficit, low voltage and high frequency may occur at the beginning of the island's forming. Sometimes, the...
This paper presents a study on pico hydro-power generations installed at the Maewong National Park Sub Station, Maerewa, Nakhonsawan Province, Thailand. The study was carried out by the School of Renewable Energy Technology, Naresuan University. The test results show that the two demonstration systems have generated the power as designed. The two systems are a standalone unit and a hybrid system comprises...
Power system information integration requires for the realization of open access,? data sharing and data combination among all kinds of application systems. As a standard transmission format, XML provides methods for describing structural data, has capability of data self-description and is independent of platform. These characteristics are fit for information exchange in power system. According to...
Transient stability analysis is very important to find the behavior of the synchronous machines under faulted condition. In this paper, IPSA simulation software is used to study the transient stability analysis of Gadong Power Station. Three-phase faults are considered at the busbar 1415LPS and 2829GPS1 with different fault clearing times. From the location at 1415LPS busbar, it is found that the...
North American electric power systems are in the early stages of transforming to the Smart Grid, a system that combines existing utility grids with new digital technology to improve overall system efficiency and supply reliability.
This paper presents the power energy effect under unbalance condition and discusses the relation between power loss and unbalance degree. Then a new topology structure of SVC based on the principle of unbalance compensation is proposed to solve the unbalance problem in power system and the energy efficiency is analyzed by an actual experiment with the compensation of the new SVC. The experimental...
The growth of the demand for electrical energy leads to loading the transmission system near their limits. Thus, the occurrence of the LFO has increased. Low frequency oscillations (LFO) in power system occur usually because of lack of damping torque to overcome disturbances in power system such as changes in mechanical power. Traditionally, power system stabilizers (PSS) are being used to damp these...
Power system stabilizers (PSSs) play an important role in suppressing low frequency oscillations. In multi-machine power systems, the objective of optimal PSS parameter tuning should not only be to damp electromechanical modes strongly related to the pertained generator, but also to take the damping status of other generators into account. Taking this in mind, a new assessment criterion from the perspective...
The implementation of energy-saving dispatch represents a significant change from the current economic dispatch and will impose some challenges for the secure operation of power systems concerned such as automatic generation control (AGC). In this work, the impacts of energy-saving generation dispatching on power system security especially on the operation performance and control strategies of AGC...
Based on the frequency characteristics analysis, the selection criterion of lumped parameters circuits are presented in this paper. Firstly the Γ section equivalent circuit is introduced as the equivalent of transmission line and its validity is proved. With other lumped parameters circuits, their frequency characteristics are analyzed and compared with the distributed parameters circuit. From characteristic...
This paper proposes a technique to identify locations of fault along the transmission network systems using Discrete Wavelet Transforms (DWT). The maximum coefficients of the positive sequence current obtained from all buses are compared in order to detect the faulty bus on a transmission network and the first peak times obtained from the faulty bus are used as an input data for travelling wave equation...
Thailand has a variety of energy sources at hand, such as biogas, hydropower and geothermal as well as solar energy, all of which can be exploited for the growing demand for energy in the country but is still dependent on foreign supply. The country has to use a considerable share of its budget to import energy. Whereas the most important location of energy consumption is in the industrial area around...
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