Abstract: To improve the hydraulic turbine regulation system with dead zones and mechanical delay, a control method based on the auto-coupling PID control theory is studied. First, we examine a delay turbine regulation system with dead-time links which delay, dead-time nonlinear factors, uncertainties and external disturbances are defined as the total disturbances; by introducing virtual controls, it is equally mapped to a double closed-loop system with an outer loop second-order linear disturbance system and an inner loop first-order linear disturbance system. Then, using the speed factor, we design an auto-coupling PD controller for the outer ring and an auto-coupling PI controller for the inner ring. Finally, the robust stability and anti-disturbance robustness of the closed-loop control system are analyzed in the complex frequency domain. The simulation results show that under different working conditions, the designed controllers gain better anti-disturbance robustness, and their dynamic quality and steady-state performance are improved significantly.

Key words: hydro-turbine regulating system, delay system, nonlinear dead zone, auto-coupling PID, virtual controller