Nonlinear modeling and stability analysis of asymmetric hydro-turbine governing system

This paper aims to study the stability and nonlinear dynamics of hydro-turbine governing system with asymmetric water diversion system, i.e. asymmetric hydro turbine governing system, by using Hopf bifurcation theory. Firstly, the full nonlinear mathematical model of asymmetric hydro turbine governing system is established by all system components and nonlinear head loss. This model contains two units with different capacities which share a common pipeline. Based on the nonlinear mathematical model, the multi-stability charac-teristics of asymmetric hydro turbine governing system under load disturbance is studied by using stable domain and verified by numerical simulation. Moreover, the multi-time scale oscillation is revealed and its relationship to system multi-stability is investigated. Furthermore, the effect of system parameters and topological parameters on system stabil-ity is analyzed. Results indicate that: two stable domains are emerged under load distur-bance, the overall stability of asymmetric hydro turbine governing system is determined by the intersection area of the two stable domains. In addition, the system parameters and topological parameters both have obvious effect on system stability, which can be sig-nificantly improved by reasonable tuning of system parameters and optimization of water diversion system layout.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

This study aims to investigate the stability and nonlinear dynamics of a hydro-turbine governing system with an asymmetric water diversion system using Hopf bifurcation theory. A full nonlinear mathematical model of the system is established, including all components and nonlinear head loss. The study explores the multi-stability characteristics of the system under load disturbance using stable domain analysis and numerical simulation. It also reveals the presence of multi-time scale oscillation and investigates its relationship with system multi-stability. The effects of system parameters and topological parameters on system stability are analyzed.