Self-adaptive Control Strategy for Main Steam Temperature of Thermal Power Unit Based on Backstepping Sliding Mode

Aiming at the strong interference and uncertainty in the main steam temperature control system of gas-fired boiler in thermal power generation unit, taking advantage of the insensitivity of sliding mode control to system parameter changes and disturbances, a main steam temperature optimization control strategy based on the combination of inverse sliding mode control and adaptive algorithm was proposed.The disturbance and uncertainty in the main steam temperature control process were attributed to the total disturbance of the system. By designing the Lyapunov function and the virtual control quantity, the inversion sliding mode control one-stage temperature reduction coarse adjustment controller was gradually introduced.On this basis, an adaptive algorithm was used to estimate the total disturbance of the system, and a two-stage temperature reduction fine-tuning controller based on adaptive inverse sliding mode control was designed.MATLAB simulation results show that compared with the control strategies of conventional PID and inversion sliding mode, the adjustment time of the proposed control strategy is reduced by 126.9 s, and the overshoot is reduced by 20.1%, and the anti-interference and robust performance of the system are effectively improved. The engineering application results show that using the proposed strategy, the main steam temperature control deviation is less than ±4 ℃, and the system stability and anti-interference ability are significantly improved.