A novel control strategy for ORC system with unsteady heat source

Abstract

A novel control strategy, named disturbance based control input design, is proposed in this study to improve the performance of Organic Rankine Cycle (ORC) system with unsteady heat source. ORC system for exhaust gas heat recovery of automobile engine is taken as the example. Conventional single variable and multiple variable control strategies are introduced briefly and compared with the proposed strategy. The disturbance based control input design for ORC is also a single variable control strategy, but the control input variable is designed based on the mass flow rate of exhaust gas by means of system improvement. Simulation results show that the ORC system works steadily in the process of a sharp deceleration of engine. The power output and cycle efficiency also increase greatly and remain stable, compared with the conventional ORC system. These results also imply that the disturbance based control input can replace the conventional control input variables and improve the system performance.