Robust Control of Diesel Ship Propulsion

by Nikolaos Xiros

Overview

This book covers a number of models and control types. An integrated nonlinear state-space mode of the marine propulsion system is developed. This is based upon physical principles that incorporate uncertainties arising from engine thermodynamics and disturbances arising from propeller hydrodynamics. The mode employs artificial neural networks to depict the nonlinearities of the thermochemical processes of engine power/torque generation and the engine–turbocharger dynamical interaction; neural nets combine the required mathematical flexibility and formalism with numerical training and calibration options using either thermodynamic engine models or measured data series. The neural state-space model is decomposed appropriately to provide a linearised perturbation model suitable for controller synthesis.

The proportional–integral (derivative) control law is examined under the perspective of shaft speed regulation for enhanced disturbance rejection of the propeller load. The typical marine shafting system dynamics and configuration allow for a smart implementation of the D-term on shaft torque feedback.

Full state-feedback control is examined for increased robustness of the compensated plant against parametric uncertainty and neglected dynamics. The H¥ requirements on the closed-loop transfer matrix are appropriately decomposed to similar ones on scalar transfer functions, which give specifications that are easier to manipulate.

In effect, the methods are comparatively assessed and suggestions and practical applications are given. This synthetic approach to propulsion plant control and operational problems should prove useful for both theoreticians and practitioners, and can be easilty adopted for the control of other proceses or systems outside the marine field, as well.

Product Details

ISBN-13:	9781852335434
Publisher:	Springer London
Publication date:	08/05/2002
Series:	Advances in Industrial Control
Edition description:	2002
Pages:	214
Product dimensions:	6.10(w) x 9.25(h) x 0.24(d)

Table of Contents

1 Introduction.- 1.1 The Marine Diesel Propulsion System.- 1.2 Contribution of this Work.- 2 Marine Engine Thermodynamies.- 2.1 Physical Engine Modelling.- 2.2 Turbocharged Engine Model Variables.- 2.3 Turbocharged Engine Dynamical Equations.- 2.4 Turbocharged Engine Algebraic Equations.- 2.5 Cycle-mean Model Summary and Solution Procedure.- 2.6 Summary.- 3 Marine Plant Empirical Transfer Function.- 3.1 Black-box Engine Modelling.- 3.2 Shafting System Dynamical Analysis.- 3.3 The Plant Transfer Function.- 3.4 Summary.- 4 Robust PID Control of the Marine Plant.- 4.1 Introduction.- 4.2 Application Aspects of Marine Engine Goveming.- 4.3 PID H-infinity Loop Shaping.- 4.4 PI and PID H-infinity Regulation of Shaft RPM.- 4.5 D-term Implementation Using Shaft Torque Feedback.- 4.6 Summary.- 5 State-space Description of the Marine Plant.- 5.1 Introduction.- 5.2 The Neural Torque Approximators.- 5.3 State Equations of the Marine Plant.- 5.4 State-space Decomposition and Uncertainty.- 5.5 Transfer Function Matrix of the Marine Plant.- 5.6 Summary.- 6 Marine Plant Robust State-feedback Control.- 6.1 Introduction.- 6.2 Supervisory Setpoint Control of the Marine Plant.- 6.3 Full-state-feedback Control of the Marine Plant.- 6.4 State-feedback and Integral Control of the Marine Plant.- 6.5 Summary.- 7 Closure.- 7.1 Conclusions and Discussion.- 7.2 Subjects for Future Investigations and Research.- Appendix A Non-linear Aigebraic Systems of Equations.- Appendix B Second-order Transfer Function with Zero.- References.