Research on the Cascade Active Disturbance Rejection Control of Superheated Steam Temperature Based on Gain Scheduling

Abstract

The boiler superheated steam temperature (SST) is a typical thermal process with great inertia and large delay. Its dynamic characteristics tend to change significantly with the variation of the operating point so that constant-parameter control system are not able to provide satisfactory dynamic control performance. Cascade active disturbance rejection control systems are commonly used in the control of the process with high order, especially in the control of superheated steam temperature. However, with the variations of loads, the tuning of linear ADRC (LADRC) becomes more complex. In order to simplify the tuning of bandwidth-parameters of LADRC in different loads, this paper studies control effects of cascade ADRC system of SST applied gain scheduling. Simulation results demonstrate that scheduling the bandwidth of feedback control system best improves dynamic characteristics of SST control system. Compared with the optimization of bandwidth-parameters using fruit fly algorithm, gain scheduling has better control performance in the control of SST.