An Optimal Multivariable ADRC Controller Design for Solar-Driven Carbon Compression Waste Heat Utilization System

Abstract

CO2 compression is one of the most important processes of the carbon capture and storage technology, which consumes a lot of cooling water and electricity, and emits a large amount of low-temperature waste heat into the environment. The consumption of energy and cooling water of CO2 compression process are the key reason for the high operating and construction costs of carbon capture and storage systems. Aiming at reducing the cost, this paper proposes a solar-driven organic rankine cycle system coupled with carbon compression cooling process for low-temperature waste heat utilization, called the ORC-CCC. It can effectively reduce the amount of cooling water and compensate for the energy consumption of the CO2 compression process. On the other hand, the cascaded and coupled energy utilization measures cause complex multivariable coupling and strong nonlinearity in the ORC-CCC dynamics and thus it is difficult to control it well. Therefore, based on the mathematical analysis on variable coupling characteristics of the ORC-CCC dynamic simulation system which we have built, a novel multivariable active disturbance rejection controller with a feedforward compensator (MADRC-FF) according to the coupling characteristics is proposed, and genetic algorithms is used to optimize the controller parameters. Since the MADRC- FF is more complex in structure compared with the traditional decentralized active disturbance rejection control, this paper theoretically proves its stability, feasibility and decoupling ability. The simulation verified its validity and better performance in multivariable control.