Modified active disturbance rejection control for fluidized bed combustor

As a widely-used technology, fluidized bed combustor (FBC) boiler is facing many control challenges such as coupling, high-order dynamics and nonlinearity. With more and more sustainable energy integrating into the bulk power system, the FBC boiler is obliged to speed up the respond to the automatic generation control command and this results in great challenges for keeping the bed temperature in the desired range. To this end, a modified active disturbance rejection control (MADRC) is put forward for high order systems with the type of K∕(Ts+1)n to enhance the control quality of the FBC boiler. Firstly, a simulation is carried out to discuss the estimation ability of the MADRC. A theorem about the stability analysis of the MADRC is provided and proofed theoretically. To help the field personnel to understand and use more easily, an effective tuning procedure is also concluded. Besides, a tuning toolbox based on the tuning procedure is established. Simulations and comparative experiments based on the Peltier temperature control platform validate the superiority of the MADRC, where the MADRC is able to enhance the control quality. Then the MADRC and other comparative controllers (the proportional integral controller and the regular ADRC) are designed for the FBC boiler. Simulation results illustrate that the MADRC can obtain the best performance. Statistical indices show that the MADRC has the smallest overshoot and shortest settling time. In addition, the MADRC still has the strongest ability to reject the input and coal quality variation disturbances. The advantages of the MADRC guarantee the high control quality and can be applied to industrial practice widely.