An Adaptive State Estimator for Pulverizer Control Using Moments of Particle Size Distribution

Review of control and fault diagnosis methods applied to coal mills

“…Primary air damper position and mill revolving speed are used as the control variables. Y. Fukayama et al [70] proposed an adaptive state estimator using the mill dynamic model with the extended kalman filter. The estimator is designed for controlling the pulverized fuel flow and the particle size distribution at the mill outlet, which is adaptive to the changes in coal grindability.…”

“…Methods like MPC [66][67][68][69][70][71][72][73][74][75][76][77] are able to achieve tight control with less overshoot for the mill system. The strength of using MPC is that the constraints on the input and output variables can be handled easily and the large time delay encountered in the milling system can be taken care of by the feed forward design of MPC, but these methods need accurate mathematical models for mills.…”

“…Hence, the control performance is highly influenced by the accuracy of the model. The MPC approach developed for mill control [66][67][68][69][70][71][72][73][74][75][76][77] should be checked under different and varying operating conditions of the mill.…”

Fault Detection in Coal Mills Used in Power Plants

“…Controllers for the coal mill are designed in (Rees and Fan 2003) and (Hasselbacher et al 1992). High order dynamic models and observer design for coal mills are the topics in (Fukayama et al 2004). However, the interest has not previously been addressed on the monitoring of the coal mills with the purpose of detecting any emerging faults.…”

Observer-Based and Regression Model-Based Detection of Emerging Faults in Coal Mills

“…Some examples dealing with modeling of coal mills are (Rees and Fan 2003), (Zhang et al 2002) and (Tigges et al 1998). High order dynamic models and observer design for coal mills are the topics in (Fukayama et al 2004). In (Odgaard and Mataji 2005) a method for detecting emerging changes in the coal moisture content is designed.…”