Fault-Tolerant Control of an Offshore Ocean Thermal Energy Conversion System with Output Constraints

Abstract

A fault-tolerant control method is investigated for an offshore ocean thermal energy conversion (OTEC) system with constraints in this work. In the system modelling, the distributed parameter system is used to build the OTEC system, which is expressed by a set of partial differential equations (PDEs) and ordinary differential equations (ODEs). Moreover, a boundary fault-tolerant control scheme is proposed to solve actuator failures. Meanwhile, according to the control scheme, system vibration suppressing and system stability can be realized. Two proposed coupled controllers are designed to solve actuator faults while considering the output nonlinearity of the OTEC system. In addition, the stability of the OTEC system based on barrier Lyapunov function is proven by simulation results, which verifies the effectiveness of the proposed coupled fault-tolerant-boundary control method. Finally, the proposed method can effectively improve the performance and safety of ocean thermal energy conversion in the OTEC system.