Analysis of nonlinear model following control/internal model control (MFC/IMC) structure for a ship engine speed control

Ship governors are usually designed on the basis of PID (Proportional Integral Derivative) controllers because of their simplicity, reliability and universality. However, their performance in various environmental conditions is not as good as desired. These disadvantages can be overcome by adaptive controllers, although these methods are complex. This article presents a new control loop structure for a ship engine speed control based on the model following control (MFC) and internal model control (IMC) theory. The new structure presented has the advantages of both the PID and robust control methodologies. It is robust for large parameter variations and strong environmental disturbances. Simulations using MATLAB®/Simulink® software for a real ship engine parameters showed high effectiveness of MFC/IMC structure for speed-keeping and speed-changing.