Dynamics and control implementation of a supercritical CO2 recuperated cycle☆

The wide interest in supercritical CO2 power cycles is motivated by promising efficiency, competitive costs and enhanced flexibility with respect to competing systems. This work is part of the effort of the SOLARSCO2OL European research project to build a sCO2-CSP power demo plant at MW scale. A dynamic model of a simple recuperated sCO2 cycle is developed in TRANSEO tool with table of properties implemented whenever possible, to enhance the computational performance of the code. The resulting model is able to compromise result accuracy with execution time, along the periods required by the typical transients of the plant, which are mainly thermal-driven. The dynamic model is used to characterised the main system responses, basing on design data, and to verify control logic effectiveness. The proposed controllers are tested showing the response of the main parameters of the plant to a load ramp variation. Stable compressor inlet pressure is achieved with an inventory control, while a stable turbine inlet temperature allows a high efficiency in part-load operation.