Controlling condensate outlet temperature on an air cooled condenser in MATLAB/SIMULINK

Abstract

With an ever increasing electrical power demand, the importance of plant simulations remains important for both personnel training and system design. Individual components may be modeled alone to analyze performance of a specific subsystem. One such subsystem of interest is an Air Cooled Condenser (ACC), as it provides an ideal cooling solution to those power plants subjected to strict water usage requirements as well as those lacking a sufficient nearby water source. An ACC was modeled for simulation in MATLAB/Simulink. The goal of the simulation was to successfully implement a triple cascade control that could maintain the condensate outlet temperature at a designated value. The physical portion of the model consists of three node types: steam/water nodes, metal nodes (pipe wall), and air nodes. The control portion of the model employs a triple cascade control with the use of PID control blocks. There were three variables used to control the temperature; steam extraction percentage, fan speed percentage, and air recirculation percentage. The simulation was then tested under various transient conditions. At present time the physical model is performing exceptionally and the controls sufficiently maintain the desired values under certain conditions, however transient responses require additional tuning. Limitations of the model are addressed and areas for future work are suggested.