Calculation Of Hydraulic Transients In A Hydraulic Machinery System

In recent decades, China's hydropower has made great achievements, with a total installed capacity of hydropower being ranked first in the world. With the rapid development of hydropower, a large number of large power stations are in the project construction or in the design stage. In the present situation, the research on transient process of hydropower station is very important.Transient process is widely shown in power generation process, it is a complex nonlinear system affected by the water system, mechanical system and electrical system. The process involves every element of the hydropower generation. The paper establishes the mathematical models of the water diversion and power generation system, then the paper makes solution analysis on the mathematical models with the methods of characteristic method, Runge-Kutta method and other methods. The paper fully considers of the affection of the flow speed of hydraulic turbine and the affection between water hammer and surge tank.The author develops the simulation program of the transition process of a hydropower station on C++ Builder platform, chooses the appropriate laws of the guide vane opening and closing, determines the elevation of the installation of surge tank, calculates the pressure distribution within the pipelines, draws the turbine speed, working head and the output torque curves, gets the laws of water level fluctuation of the surge tank, the pressure and flow inside the pressure pipes. The station runs safely, stably and efficiently in this design and control. The possible error in the calculation is analyzed and discussed.The calculation of the transient process based on the computer is fast and accurate reflecting the actual process of transition, and the result is intuitive and easy to be analysed, providing the data basis for optimal design and reasonable control.