Adaptive fault-tolerant PI tracking control for ship propulsion system

Area of Science:

• Marine Engineering
• Control Systems Engineering
• Fault-Tolerant Control

Background:

• Ship propulsion systems require robust control for reliable operation.
• Actuator effectiveness loss can significantly degrade performance and safety.
• Existing control methods may not adequately address dynamic fault conditions.

Purpose of the Study:

• To develop a fault-tolerant tracking control strategy for a ship propulsion system.
• To address issues arising from loss of actuator effectiveness.
• To ensure sustained performance and system stability during fault conditions.

Main Methods:

• Formulation of a faulty propulsion system model incorporating actuator effectiveness loss.
• Design of a nominal proportional-integral (PI) controller using H_∞ output feedback.
• Development of a fault-tolerant PI control scheme with an adaptive tuning law for online gain adjustment.

Main Results:

• The nominal PI controller achieves desired tracking performance in fault-free scenarios.
• The proposed fault-tolerant scheme effectively compensates for actuator effectiveness loss.
• The adaptive tuning law ensures online adjustment of controller gains for sustained performance.

Conclusions:

• The proposed fault-tolerant PI control strategy is simple and implementable.
• The method guarantees graceful tracking performance and robust fault-tolerant capability.
• Demonstrated effectiveness through a case study on a ship propulsion system.