Tuning of boiler drum level controller in Power Plant

摘要

The objective of drum level control of boiler in thermal power plant is to maintain drum level at constant set point regardless of disturbance such as main steam flow. The implemented drum level control is cascade control that is composed of two PI controllers. The important factors in drum level controller are the parameters of two PI controllers. The tuning of cascade controllers is more difficult, time-consuming and tedious than that of single controller and requires a lot of trial and errors. Besides, a drum level process is an integrating process with transient inverse response. In this paper, the relay feedback tuning method is applied to tune cascaded PI controllers for drum level control. Finally, the simulation result using a coal-fired drum-type fossil power plant simulator shows the validity of tuned cascaded PI controllers for drum level control using relay feedback tuning method.