Comparison Study On Navigation Structure For Silin Hydropower Station

With the development of "West-East electricity transmission” project, a large number of hydropower projects have been developded in West China in recent years. And many of them have been completed and successfully put into operation. At the mean time, navigation systems of the hydropower projects are constructed, which helps the socio-economic development. The rivers in West China commonly have seasonally varying discharges and are ususally narrow, so most of the hydropower projects have big reservoirs with high dams. This makes shiplifts most suitable for the navigation systems.Taking the Silin Hydropower Station located in Sinan County of the Northeastern Guizhou province as an example, the selection of machinery and electrical equipments for the vertical shiplift was studied in this thesis study. The study was mainly based on theoretical calculation and the design of other similar projects was surveyed for reference.The wire rope hoist shiplift was chosen for the navigation system of Silin Hydropower Station. Since the main hoisting equipment of the ship lis large, the design and manufacturing of the main machinery are difficult. Moreover, the vertical ship lift system requires high reliability and safety of the whole power supply system. Thus there is a strict requirement for the type and parameters of the electrical equipments. In addition, the system also has a strict requirement on the lighting, ground, communication and other key systems for they may affect the safety of the passing boats, passengers and cargo.The above mentioned vertical shiplift was chosen based on historical data analysis according to standards of the nation. From this, the electrical equipments were preliminarily chosen and designed based on survey as follows: Since the power supply system is of most importance, to ensure the reliability of power supply, there should be three relatively independent power supply systems, and independent diesel generators should be equipped as emergency power supply system; the main hoisting system should use the digital variable frequency speed control technology; the capacity of the transformer should consider the load coincidence factor, and the selection of impedance should meet the requirements of short circuit current; the lighting system should be selected according to the requirement of illumination; the ground system should be connected to the main ground system of the Silin Hydropower Station and the resistance should fullfil the requirement of both the hydropower project and the lectrical equipments of the navigation system; the communication system should ensure safety of the ships under all-weather meteorological conditions.