In order to study the nonlinear dynamics characters of hydro-turbine governing system with a complex pipe system, a nonlinear model of hydro-turbine governing system was established where one considered the nonlinearity of transfer coefficient with the hydro-turbine governing system work conditions changing. Based on nonlinear dynamics theory, the nonlinear dynamic behavior of hydro-turbine governing system was analyzed including bifurcation diagrams, Poincare maps, power spectrum diagram, time domain diagram, phase orbits diagram and spectrum diagram. Furthermore, numerical simulations were carried out， it shows that the law between the rotation speed of hydraulic turbine and watergate opening degree was discovered when the parameters of hydro-turbine governing system are varying. And the parameters range of the hydro-turbine governing system which can ensure the system work in stable condition was got. The results show that when governor parameters varying in the stable area of system response bifurcation diagrams, the system work in a stable condition, while, if governor parameters exceed the area ,the output of hydro-turbine governing systems appears constant amplitude, divergence, and even chaos. Therefore, all of these results provide the theoretical basis for the system working well.
Huang Zhiwei，Zhou Jianzhong，Zhang Yongchuan．Dynamic Analysis on Hydraulic Generator Rotors With Coupling Faults of Misalignment and Rub-impact[J]．Proceedings of the CSEE，2010，30(8)：88-93(in Chinese)．
Sheng Wemei，Xiaoyang Gui，Chen shen，el al．Dynamic extending nonlinear H∞ control and its application to hydraulic turbine governor[J]．Science in china series E: Technlolgical Sciences，2007，50(5)：618-635．
Zhu Yuanyue，Fan Honggang，Chen Naixiang，et al．Prevention of self-excited oscillationsin complicated water diversion channels of pumped storage power stations[J]．Journal of Tsinghua University (Science & Technology)，2006，46(24)：1434-1437(in Chinese)．