Kalman filter applications for coal-fired generating unit control

CUTLASS is a high-level language developed for the control of power station boiler/turbine units. It provides considerable flexibility for implementing different control strategies. Much of the control system refurbishment once consisted of replacing analogue PID controllers with equivalent digital PID controllers. There was, however, the need to start to develop improved strategies to meet the growing requirements for changing load, minimizing plant damage and meeting environmental criteria. The use of Kalman filters has increased the accuracy with which plant states can be estimated and consequently the control of them has been enhanced. This enables generators to achieve their target demand accurately and respond effectively to plant constraints whilst minimizing control action. The avoidance of unnecessary control action helps to maximize plant efficiency, improve the environmental performance of the plant and minimize plant wear. Significant practical benefits have been achieved and the use of simple algorithms has ensured that the resulting control systems are readily comprehensible to station staff who are responsible for their maintenance.