Selection of hydropower station, turbine and main valve

Release time:

2024-06-19

Water energy is one of the most economical energy sources, and it is also a kind of energy that can never be consumed. There are many rivers, lakes and oceans on the earth, which contain abundant hydropower resources. With the help of the sun, the water on the earth is evaporated into steam. In the sky, the steam condenses into rain and snow and falls to the earth. Through rivers, it flows into the ocean. This cycle is endless. Therefore, hydropower generation is the most economical way of power conversion, which has many advantages compared with coal power and nuclear power. It does not consume fuel in operation, and its operation management and power generation cost are low, even only the relationship of thermal power generation; it can be started and put into operation quickly from the static state in a few minutes with fast start-up; it is suitable for peak regulation, and it does not produce chemical changes and harmful substances in the process of transforming water energy into electric energy, so it is a clean energy.

The basic principle of hydropower is to use the water level drop to integrate the hydro generator to generate electricity, that is, to use the running energy of water to convert into the mechanical energy of the hydro turbine, and then use the mechanical energy to push the generator, after the generator is added to the excitation, establish the voltage, and start to send the electric force to the power system after the breaker is put into operation. If you want to adjust the output of the generator set, you can adjust the opening of the guide wing to increase or decrease the water volume. After the power generation, the water will return to the river channel through the draft tube to supply the downstream water.

By the end of April 2015, the installed capacity of hydropower stations in China has exceeded 300 million KW, accounting for a quarter of the world. Of course, after the construction of a hydropower station, there may also be sediment deposition, inundation of good farmland, forests and historic sites, especially large reservoirs, which may also induce earthquakes. Its construction period is also longer than that of thermal power station, and the investment in kilowatts of hydropower station is much higher than that of thermal power station. Hydropower station is a comprehensive engineering facility which transforms potential energy of water into electric energy by means of hydraulic structures and electromechanical equipment. In order to use water flow to generate electricity, it is necessary to concentrate the natural drop and control and adjust the natural flow. The form of hydropower station mainly depends on the way of concentrated water head. According to the different ways of concentrated water head, hydropower station is divided into dam type hydropower station, diversion type hydropower station and hybrid type hydropower station.

Selection of main valve

The effective flow area of gate valve and ball valve shall not be reduced, the full opening resistance coefficient shall be 0, and the diameter of main valve shall be consistent with the section at the inlet of volute. Due to the existence of butterfly plate, the effective flow area of butterfly valve is reduced. When selecting butterfly valve, the effect of the reduction of the effective flow area of butterfly valve with different water heads should be considered.