Robust multivariable-cascade governors for hydroturbine controls

Hydro turbine speed control using robust cascade governor controllers

“…is the output turbine speed and R ref is the reference. The gate position deviation ÁG is used as an intermediate output to improve the performance of the system [4,18]. The cascade control (C.C.)…”

“…Early governors were mechanical hydraulic controllers and they did not normally permit the wide governor loop bandwidth [1,4]. Empirical methods were used to adjust parameters of the governors in early power systems since these systems were small, often geographically remote from the consumer loads and individually isolated.…”

“…Classical control theory was used up to the late 1960s for designs of governors, but the design theory had been for SISO control systems and provided no systematic design methodology for complex systems. The classical governors did not provide sufficient control performance due to increasing problems [4,[8][9][10]. Modern electrical governors have been used since 1960.…”

“…The electrical governors not only improve the linearity of the dynamic response of the system, but also provide a variety of control functions [11]. Supplementary signals have been used to improve stability margins of the systems [2,4]. In the 1970's, optimal control theories were used in the design of governors [9,12].…”

“…Few papers have considered the C.C. topology for the systematic design of the governor using robust control methods [4,8,16,18]. There is no published literature about the application of cascade control structure to governing units in power systems; these are the contributions of this paper.…”