This paper presents new techniques of Automatic Generation Control (AGC) technology which are employed to increase the certain demand of power system stability and control. Today, power system control operation is fully automated with an Automatic Generation Control (AGC) technology and improves the reliability, productivity and efficiency of power industry. The power generating equipment can be controlled by maintaining the power system frequency at constant value. And power system frequency control is achieved by Automatic Generation Control (AGC) and governing systems of individual turbine-generators. This achieves the automation of whole power plant based on automatic control of water-turbine generator. Therefore the mechanism of Automatic Generation Control (AGC) makes operation limitation condition units that ensure the safe operation of power plant with the principle of Energy Management System and primary functions. At the time of carrying out these functions, it is necessary to avoid the frequent start/stop of units caused by short-term load fluctuation of power system and detail problems are discussed in the paper. At the end study is also focused in engineering problems and target function of Automatic Generation Control (AGC) in hydropower plant.

Coal is known as black gold, the food of industry. It has been used as one of the main energies for human being since the 18th century. Although its important place has been taken by petroleum nowadays, due to the daily drying up of petroleum for quite a period of time in the future, the large quantity of coal reserves and with the rapid development of science and technology, especially maturity and wide use of integrated coal gasification technology, coal will become one of the energies that cannot be replaced in human life and production. Coal increased fastest for five successive years. Coal consumption increased by 4.5% in the world which is higher than the average level 3.2% of last ten years. However, the use of coal has brought up serious ecological environment problems. In the 20th century, serious air environmental pollution events, such as acid rain, damage to ozonosphere, global warming, photochemical smog and urban coal smog, are all related to coal burning. The principal source of main pollutants in air, for example, SO₂, NO_x, CO, fume dust, particles, organic pollutants and heavy metals, are caused by coal burning. These pollutants have caused irreversible damage to human health and ecological environment. Finally this paper describes coal consumption and environmental problems due to coal utilization.

Condition-based maintenance is a kind of maintenance which conducted before fault by judging device exception and predicting device fault based on device condition information provided through monitoring device condition. The analysis result of fault diagnosis technology and production management information system which has namely arranged the maintenance plan. The implement device maintenance in light of device health condition due to prevents excessive maintenance or disrepair of device to the utmost extent. During operation, primary device of hydropower plant constantly suffers from sand abrasion, cavitation damage, mechanical wear and other mechanical or electrical damage, which reduces the efficiency of generating equipment and shortens the service life. If timely monitoring and diagnosis and appropriate maintenance are not provided, accident may be induced and cause great economic losses; to make primary devices for production and transmission of electric energy of hydropower plant have high reliability and be in good operating conditions, such primary devices must be maintained. The aim of this paper is to define the gradually improving sensor and monitoring technology which offer the possibility of condition-based maintenance of hydroelectric generating unit and the extraction and analysis methods of fault characteristics. Therefore discussion is summarized briefly on composition, configuration and functions of Condition-based Maintenance System (DSS). And also describes the short introduction of Condition-based Maintenance (DSS) system in typically project of Songjianghe Hydropower Plant as used for primary devices.

An Integral part of generator is Excitation System and new technology of Excitation System has been developed utilizing a power sources. The most important a portion of electric power system is synchronous generator due to it is the source of electrical energy and energy transformation is possible only when generator excitation exists. The generator excitation systems work when generator excitation system operates a dc charge to the generator heads to energize the field of magnetic around them to enable the electricity that should be generated. There are brushless and brush-type exciters and generators are built in exciters or charge can be established from any external source. This paper presents the control and configuration of synchronous generator excitation system as current mainstream technology, which is widely designed for feeding of turbo generator excitation winding with auto- regulated DC in generator operation, control normal and emergency modes. In this paper discuss appended on excitation system models of synchronous generator and emphasis on drawbacks, different possibilities to regulate generator excitation, de-excitation systems and overvoltage Protection with special newly developed nonlinear system regulation. And also append short descriptions of functions, compositions, Structure and Working Principle of Generator Excitation System.

In 1927, the limestone desulfurization process was first applied in the Barthes and Bansside Power Plants (total 120MW) beside the Thames River in UK to protect high-rise building in London. Up to now, over 10 desulfurization processes have been launched and applied. Based on the desulfurizing agent being used, there include calcium process (limestone/lime), ammonia process, magnesium process, sodium process, alkali alumina process, copper oxide/zinc process, active carbon process, ammonium dihydrogen phosphate process, etc. The calcium process is commercially available and widely used in the world, i.e. more than 90%. Flue gas desulfurization processes, survey made by the coal research institute under the International Energy Agency shows that the wet-process desulfurization accounts for 85% of total installed capacity of flue gas desulfurization units across the world. The wet-process desulfurization is mainly applied in countries, like Japan (98%), USA (92%), Germany (90%), etc. The limestone-gypsum wet desulfurization process, the most mature technology, the most applications, the most reliable operation in the world, may have rate of desulfurization of more than 90%. Currently, the flue gas desulfurization technology used at thermal power plants at home and abroad tends to be higher rate of desulfurization, bigger installed capacity, more advanced technology, lower investment, less land acquisition, lower operation cost, higher level of automation, more excellent reliability, etc. This paper briefs current situations and trends of flue gas desulfurization technology also append short descript of different type of FDG and their category.

To prevent from the hazards of mountain torrent disasters, today's monitoring and early warning system is widely used in mountain areas to keep alert from the rainstorm. Mountain torrent disaster caused by the rainstorm and is one of the most important reasons, resulting in transportation blocks and mass casualties. Mountain torrent disaster occurs frequently depends on the weather of mountain's country. It can be distinguished and predicted by monitoring and early warning system to provide the safety reference in disaster presentation and reduction. This paper presents the analysis and key management of monitoring and early warning system of mountain torrent which mainly includes monitoring system and early warning system of water and rain information. In order to achieve better effect of disaster prevention and reduction, establish an organization system of mass observation and mass prevention and enhance training propaganda. The monitoring system of water and rain information mainly includes network layout of water and rain monitoring station, information acquisition, information transmission and communication networking and configuration of devices. Early warning system of mountain torrent is composed of platform-based early warning system of torrent defense and early warning system of torrent mass observation and mass prevention. And also appended short description of publicity and training includes popularization of knowledge about disaster prevention; preparations of disaster prevention, maintenance and operation of monitoring and warning facilities, publicity and rehearsal of proposal.