Open AccessUniversal finite‐time observer design and adaptive frequency regulation of hydraulic turbine systems
Author(s) -
Liu Yijian,
Lan Qixun,
Qian Chunjiang,
Qian Weixing,
Chu Hongyan
Publication year - 2016
Publication title -
iet control theory and applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.059
H-Index - 108
eISSN - 1751-8652
pISSN - 1751-8644
DOI - 10.1049/iet-cta.2015.0310
Subject(s) - control theory (sociology) , observer (physics) , turbine , integrator , controller (irrigation) , control engineering , full state feedback , state observer , computer science , engineering , control (management) , bandwidth (computing) , nonlinear system , mechanical engineering , agronomy , physics , quantum mechanics , artificial intelligence , biology , computer network
In this study, the authors consider the problem of frequency regulation via output feedback for a hydraulic turbine system under unknown load variations. First, to address the difficulties in estimating the unmeasurable states and the unknown load variation, they introduce a universal finite‐time observer ( UFTO ) which can estimate unmeasurable states, unknown parameters and disturbances under a unified framework. Based on the proposed UFTO , the unmeasurable wicket gate position, the flow rate and the load variation are estimated in a finite time for the hydraulic turbine system. Then by introducing a coordinate transformation, the state‐space model of hydraulic turbine system is converted into a simple form for which a state feedback control law is constructed using the adding a power integrator approach. Combining the UFTO with the finite‐time control law, an output feedback controller is designed to regulate the frequency of the hydraulic turbine system. Computer simulations are also given to validate the proposed finite‐time output feedback controller.