Improved PI-PD control design using predictive functional optimization for temperature model of a fluidized catalytic cracking unit

Proportional-integral-derivative (PID) control is widely used in industry because of its simple structure and convenient implementation. However, PID control is suitable for small time delay systems; while if too large delay is encountered, PID control may not obtain the desired performance. Proportional-integral-proportional-derivative (PI-PD) control is a modified of PID control and can get improved control performance; however, due to the complex controller parameter tuning, the PI-PD control is used in a limited scope. Inspired by the advantage of predictive functional control (PFC), a new PI-PD control design using PFC optimization is proposed in this paper. The proposed method not only inherits the advantage of PFC, which does well in coping with the time delay, but also has the same structure as the PI-PD controller. The proposed method is tested on the preheated temperature control of crude oil in a fluidized catalytic cracking unit. The results show that the proposed controller improves control performance compared with typical PID control and PI-PD control.