Optimizations On The CCS Strategy Of CFB Boiler Unit

Because of complicated combustion process of CFB,many problems still exist in the design of CFB boiler's automatic control system especially the coordinated control system (CCS), so the operation problem is obvious. Fuzzy-PI control system is designed for the CFB boiler bed control system, simulation result shows that good performance can be obtained. The fuel amount control system has been optimized by cancelling"fuel-air"double-cross limiting and adding damp segment on the loop of fuel feedback. These three strategies are optimizations on the combustion control system. Improvements on the Turbine-Boiler main control system are as follows: Firstly, frequency regulation has been modified; Secondly,the"press deviation dragging load"loop has been designed in order to limit the response speed of turbine valve. Thirdly, the direct energy balance(DEB) strategy has been replaced by indirect energy balance(IEB) strategy; Last, fuel feedback has been used to compensate the time delay of the CFB boiler. The performance of the improved coordinated control system is evaluated at last.