Nonlinear Disturbance Decoupling Control for Hydro-Turbine Governing System with Sloping Ceiling Tailrace Tunnel Based on Differential Geometry Theory

Abstract

For hydropower stations with sloping ceiling tailrace tunnel (SCTT), the regulation quality of hydro-turbine governing system (HTGS) under the proportional-integral-derivative (PID) strategy is poor. In order to improve the regulation quality of HTGS, the nonlinear disturbance decoupling control (NDDC) based on differential geometry theory is firstly applied into the HTGS with SCTT. The rigorous and complete construction method of nominal output function is proposed. Based on the obtained nominal output function, a novel NDDC strategy for HTGS with SCTT is designed. The application and performance of NDDC strategy on HTGS with SCTT are revealed. The results indicate that the regulation quality of the HTGS with SCTT under NDDC strategy is obviously better than that under PID strategy. The NDDC strategy has a favorable applicability on SCTT. The robustness of the HTGS with SCTT under NDDC strategy is excellent. In real engineering cases, the NDDC strategy can be adopted to optimize the design of the governor and improve the power supply quality of hydropower station.

A Review of the Hydraulic Transient and Dynamic Behavior of Hydropower Plants with Sloping Ceiling Tailrace Tunnels

“…A comparison between the regulation quality of the NSF control strategy and the PID strategy ( Figure 27) indicated that the dynamic performance and response speed under the former were obviously better than those under the latter. In Reference [46], Guo studied another nonlinear control strategy, i.e., a nonlinear disturbance decoupling control (NDDC) strategy, for HTGSes with SCTTs. The theoretical basis of the NDDC strategy is differential geometry theory.…”

“…In terms of Issue 6, it is discussed in References [45][46][47][48][49][50][51][52]. The control of transient processes relates to the regulation quality of hydropower plants with SCTTs.…”

“…The control of transient processes relates to the regulation quality of hydropower plants with SCTTs. In References [45][46][47][48][49][50][51][52], the regulation quality of HTGSes with SCTTs was studied, and several control strategies were proposed. By using the proposed control strategies, the dynamic performance of an HTGS with an SCTT can be improved.…”

“…In Section 5, the stability of HTGSes with SCTTs is discussed based on References [39][40][41][42][43][44]. In Section 6, the transient process control of HTGSes with SCTTs is explained based on References [45][46][47][48][49][50][51][52]. In Section 7, the conclusions are given, and future research trends are presented.…”

Feedback Linearization and Reaching Law Based Sliding Mode Control Design for Nonlinear Hydraulic Turbine Governing System

“…In this regard, the hydraulic turbine governing system (HTGS), as the key structure of any hydropower plant, is finely studied and designed to guarantee the operation's safety and proper response [4]. However, the essences of HTGS are nonlinear characteristic, time-variant and a non-minimum phase system, which require efforts on precise and effective studies on practical control strategy design [5][6][7]. To overcome the obstacles in nonlinear plant controlling, considerable interests and research in the applications of HTGS regulating technique have been raised in the past several decades, such as fractional-PID control [8], fuzzy control [9], predictive control [10], adaptive control [11] and synergetic control [6,12].…”