Dynamic Positioning for Engineers - Surender Kumar [2021, PDF]

Foreword (by Capt. Rajesh Tandon) ................................................................. xiii
Foreword (by Venkatraman Sheshashayee) ............................................................ xv
Preface............................................................................................ xvii
Author ............................................................................................ xix
Chapter 1 Introduction to Offshore ................................................................ 1
1.1 Drilling Operations ........................................................................... 2
1.2 Offshore Structures ........................................................................... 3
1.2.1 Fixed/Stationary Platforms .................................................................. 4
1.2.2 Jacket Platforms ............................................................................ 5
1.2.3 STAR Platforms .............................................................................. 5
1.2.4 Compliant Towers ............................................................................ 5
1.2.5 Semi-Submersible Platforms .................................................................. 6
1.2.6 Single Point Anchor Reservoir (SPAR) Platforms .............................................. 6
1.2.7 Tension-Leg Platforms (TLPs) ................................................................ 6
1.2.8 Jack-Up Platforms ........................................................................... 7
1.2.9 Floating Production Systems ................................................................. 7
1.2.10 Subsea Production Systems .................................................................. 7
1.3 Control System Used in Subsea Production ...................................................... 8
Chapter 2 Historical Background to Development of Dynamic Positioning ............................. 9
2.1 Background and History of Dynamic Positioning Development ..................................... 9
Chapter 3 The Seven Components of a DP System ..................................................... 13
3.1 Subsystems and Grouping ....................................................................... 13
3.1.1 Power ....................................................................................... 13
3.1.2 Thrusters ................................................................................... 14
3.1.3 Environmental Sensors........................................................................ 15
3.1.4 Position Reference Sensors................................................................... 15
3.1.5 Computer (RTC/DPC/Controller) ............................................................... 16
3.1.6 MMI/HMI ..................................................................................... 16
3.1.7 Operator .................................................................................... 17
Chapter 4 Six Degrees of Freedom – Basics of Dynamic Positioning .................................. 19
4.1 Ship Movement ................................................................................. 19
4.1.1 Roll ........................................................................................ 19
4.1.2 Pitch ....................................................................................... 19
4.1.3 Heave ....................................................................................... 19
4.1.4 Surge ....................................................................................... 20
4.1.5 Sway ........................................................................................ 22
4.1.6 Yaw ......................................................................................... 22
4.2 Movements Controlled and Monitored by DP ...................................................... 22
4.3 Mathematical Model ............................................................................ 25
4.4 DP System ..................................................................................... 27
4.5 Advantages and Disadvantages of the Dynamic Positioning System ................................ 28
4.6 Wind Feed Forward ............................................................................. 29
4.7 Excursion or Feedback of Ship Position ........................................................ 29
4.8 Current Feedback .............................................................................. 30
4.9 Thruster Allocation Logic ..................................................................... 31
4.10 Quick Current or Fast Learn .................................................................. 31
4.11 Kalman Filter................................................................................. 31
4.11.1 Wave Filter ................................................................................ 32
4.11.2 Advantages of the Mathematical Model ....................................................... 32
4.11.3 Model Control or Dead Reckoning (DR) ....................................................... 33
4.11.4 Limitations of Kalman Filter ............................................................... 33
4.12 DP Operational Modes ......................................................................... 33
Chapter 5 Different Types of DP Vessels and Their Applications .................................... 37
5.1 Types and Applications of DP-Enabled Ships .................................................... 37
5.1.1 Anchor Handling Tug Supply .................................................................. 37
5.1.2 Diving and Underwater Support Vessels ....................................................... 38
5.1.3 Heavy Lift Vessel ........................................................................... 40
5.1.4 Cruise Liners ............................................................................... 41
5.1.5 Other Specialised Vessels ................................................................... 41
5.1.6 DP Advantages ............................................................................... 41
Chapter 6 DP Class/Equipment Class ................................................................ 43
6.1 Introduction to DP Class ...................................................................... 43
6.2 Major Class DP Notations ...................................................................... 44
6.3 DP Vessel Class/IMO DP Class .................................................................. 44
6.3.1 DP Class 1 .................................................................................. 44
6.3.2 DP Class 2 .................................................................................. 45
6.3.3 DP Class 3 .................................................................................. 46
6.3.4 DP Class 0 .................................................................................. 48
6.4 Basic/Hardwired DP System ..................................................................... 48
6.5 Integrated/Networked DP System ................................................................ 48
Chapter 7 Basics of Electrical Propulsion and Thruster Types ...................................... 49
7.1 Basics of Electrical Propulsion and Thruster Types ............................................ 49
7.2 Diesel Electric Propulsion for DP Vessels ..................................................... 49
7.2.1 Power Generation and Distribution ........................................................... 50
7.3 Thruster Response and Accuracy ................................................................ 52
7.4 Thruster Modes ................................................................................ 53
7.4.1 Fixed Mode .................................................................................. 53
7.4.2 Thruster Biasing ............................................................................ 55
7.4.3 Push/Pull Modes ............................................................................. 55
7.5 Different Types of Propulsion Units and Thrusters ............................................. 56
7.5.1 Tunnel Thrusters ............................................................................ 57
7.5.2 Azimuth Thrusters ........................................................................... 58
7.5.3 Azipods ..................................................................................... 58
7.5.4 Diesel-Mechanical (DM) Pros and Cons ........................................................ 59
7.5.5 Diesel-Electric (DE) Pros and Cons .......................................................... 60
7.5.6 Hybrid DM/DE Pros and Cons .................................................................. 60
7.5.7 Precautions while working on CPP drives ..................................................... 61
Chapter 8 Thruster Controls and Automation ........................................................ 63
8.1 Introduction .................................................................................. 63
8.2 Thruster Response and Accuracy ................................................................ 63
8.3 Thruster Control and Automation ............................................................... 65
8.3.1 Wärtsilä Thruster Control ................................................................... 65
8.3.2 Kongsberg Thruster Control System ........................................................... 67
8.3.3 Siemens Thruster Control Systems ............................................................ 68
8.3.4 CAT (Caterpillar) Marine .................................................................... 69
8.3.5 Emergency Stop for Thrusters................................................................. 70
8.4 Thruster Monitoring and Alarm ................................................................. 70
Chapter 9 Power Management System (PMS) ........................................................... 73
9.1 Introduction .................................................................................. 73
9.2 Estimation of DP Power Requirements ........................................................... 74
9.3 Power Management System ....................................................................... 75
9.4 Power Blackouts – Causes ...................................................................... 75
9.5 Power Blackout Avoidance Strategies ........................................................... 77
9.6 Functions of PMS .............................................................................. 77
9.6.1 User Interface .............................................................................. 78
9.7 Load Sharing .................................................................................. 79
9.7.1 Power Limits ................................................................................ 80
9.8 Uninterruptible Power Supply .................................................................. 80
Chapter 10 Harmonics in Power System .............................................................. 83
10.1 Introduction ................................................................................. 83
10.1.1 What are Harmonics? ........................................................................ 83
10.1.2 Current Harmonics .......................................................................... 83
10.1.3 Voltage Harmonics .......................................................................... 84
10.2 Base Frequency................................................................................ 85
10.3 What is “Triplen” in Harmonics? .............................................................. 85
10.3.1 Sequencing pattern of harmonics ............................................................ 87
10.4 Effects of Harmonics ......................................................................... 87
10.5 Finding and Measuring Harmonics in Power System .............................................. 88
10.6 Correcting Harmonics in Power System ......................................................... 89
Chapter 11 Introduction to Environmental Sensors................................................... 91
11.1 Introduction ................................................................................. 91
11.2 Sensor Redundancy ............................................................................ 91
11.2.1 Sensor Redundancy in Triple Systems ........................................................ 91
11.2.2 Sensor Redundancy in Dual Systems .......................................................... 91
11.2.3 Sensor Redundancy in Single Systems ........................................................ 91
11.3 VRU/VRS/MRU .................................................................................. 92
11.4 Gyro Compass in a DP System .................................................................. 93
11.4.1 Gyro Compass Faults ........................................................................ 93
11.5 Wind Sensors ................................................................................. 95
11.5.1 Types of Wind Sensors ...................................................................... 95
11.5.2 Wind Feed Forward Function ................................................................. 96
Chapter 12 Introduction to Position Reference Sensors ............................................. 99
12.1 Introduction ................................................................................. 99
12.2 Basic Working Principles of the PRS/PME ...................................................... 99
12.3 Radar/Microwave-Based Systems ................................................................ 99
12.3.1 Artemis .................................................................................... 99
12.3.2 Global Navigation Satellite System (GNSS) .................................................. 100
12.3.3 Measuring of Position ...................................................................... 102
12.3.4 GPS Masking ................................................................................ 103
12.3.5 Differential GPS ........................................................................... 104
12.3.5.1 Global Positioning System (GPS) .......................................................... 104
12.3.5.2 GLObal NAvigation Satellite System (GLONASS) ............................................. 104
12.3.5.3 Galileo .................................................................................. 105
12.3.5.4 BeiDou/Compass ........................................................................... 105
12.3.5.5 The Quasi-Zenith Satellite System ........................................................ 105
12.3.5.6 IRNSS .................................................................................... 105
12.3.5.7 GPS Augmentation Services ................................................................ 105
12.3.6 Relative GPS ............................................................................... 106
12.3.6.1 Absolute Techniques ...................................................................... 106
12.3.7 Criteria for Selection of GNSS ............................................................. 106
12.4 Laser ........................................................................................ 107
12.4.1 Fanbeam .................................................................................... 107
12.4.2 CyScan ..................................................................................... 108
12.4.3 SpotTrack .................................................................................. 109
12.4.4 Target Reflectors for Laser Sensors ........................................................ 109
12.4.5 SceneScan® ................................................................................. 110
12.5 Acoustics .................................................................................... 111
12.5.1 Hydroacoustic Position Reference (HPR) or High Precision Acoustic Positioning (HiPAP) ...... 112
12.5.2 Ultra-Short Baseline or Super-Short Baseline (USBL or SSBL) System ......................... 112
12.5.3 Short Baseline (SBL) Systems ............................................................... 113
12.5.4 Long Baseline (LBL) Systems ................................................................ 114
12.6 Mechanical PRS – Taut Wire Position Reference System.......................................... 115
12.7 Frequency Modulated Continuous Wave (FMCW) Radars ............................................ 116
12.7.1 RadaScan ................................................................................... 117
12.7.1.1 RadaScan General Care and Maintenance .................................................... 117
12.7.2 RADius ..................................................................................... 118
12.8 RangeGuard ................................................................................... 119
Chapter 13 Handling of PRS/PME and Various Tests on PRS/PME ....................................... 121
13.1 Introduction ................................................................................. 121
13.2 Various Tests on PRS ......................................................................... 121
13.2.1 Freeze Test (“Live” Assessment Test) ....................................................... 121
13.2.2 Variance Test (Long-Term Accuracy Assessment) .............................................. 122
13.2.3 Prediction Test ............................................................................ 123
13.2.4 Slow Drift Tests ........................................................................... 123
13.2.4.1 Divergence Test .......................................................................... 123
13.2.4.2 Median Test .............................................................................. 124
13.3 Processing of Data From PRS/PME .............................................................. 124
13.4 Conclusion ................................................................................... 124
Chapter 14 Architecture of a DP System ............................................................ 125
14.1 Introduction ................................................................................. 125
14.2 System Architecture for a DP Class 1 System .................................................. 125
14.3 System Architecture for a DP Class 2 System .................................................. 126
14.3.1 Dual Redundant DP System ................................................................... 126
14.4 System Architecture for a DP Class 3 System .................................................. 127
14.4.1 Triple Redundant DP Systems ................................................................ 128
Chapter 15 Basics of Networking in DP ............................................................. 131
15.1 Introduction to Communications in DP Systems ................................................. 131
15.2 Networking in DP Systems ..................................................................... 131
15.2.1 Need for Networking in DP Systems .......................................................... 131
15.3 Basics of Networking ......................................................................... 131
15.3.1 Networking Used in DP systems .............................................................. 133
15.4 Common Troubles and Their Remedies ........................................................... 134
15.5 General Troubleshooting Steps for Network Problems ........................................... 134
15.5.1 Ping Command ............................................................................... 135
15.5.2 Ipconfig Command ........................................................................... 135
Chapter 16 Types of Signals Used in DP Automation ................................................. 137
16.1 Introduction – Different Types of Signals in Marine Automation ............................... 137
16.2 Serial Line Interface ........................................................................ 137
16.2.1 What is Serial Line? ....................................................................... 137
16.2.2 Data Speed – Bit Rate and Baud Rate ........................................................ 138
16.2.2.1 Data Bits ................................................................................ 139
16.2.2.2 Parity ................................................................................... 139
16.3 NMEA 0183 .................................................................................... 140
16.4 Position Reference System (PRS) Interfaces ................................................... 140
16.5 Signals Used for Environmental Sensor Interfaces ............................................. 140
16.6 Signals for Thruster Interfaces .............................................................. 141
16.7 Signals for Power Plant Interfaces ........................................................... 143
16.8 Other Interfaces ............................................................................. 143
Chapter 17 Consequence Analysis, Capability Plot, Footprints and Motion Prediction ................ 145
17.1 Introduction ................................................................................. 145
17.2 Capability Plot .............................................................................. 146
17.3 Footprints ................................................................................... 147
17.4 Motion Prediction ............................................................................ 149
Chapter 18 DP Trials and Documentation ............................................................ 151
18.1 Introduction ................................................................................. 151
18.2 IMCA Guidance on DP Trials ................................................................... 151
18.3 DP FMEA/FMECA Proving Trials ................................................................. 151
18.4 The Objective of the FMEA .................................................................... 152
18.5 Contents of the FMEA Report .................................................................. 152
18.6 Uses of FMEA ................................................................................. 153
18.7 Third Party Audit ............................................................................ 154
18.8 Annual Proving Trials ........................................................................ 154
18.9 Mobilisation Trials .......................................................................... 154
18.10 DP Vendor Reports ........................................................................... 155
18.11 DP Correspondence/Communication ............................................................. 155
18.12 DP Fault Log................................................................................. 155
18.13 DP Incident Log.............................................................................. 155
18.14 Operational Issues .......................................................................... 156
Chapter 19 Circuit Tracing and Fault Finding on DP Equipment ...................................... 159
19.1 Introduction ................................................................................. 159
19.2 How to Read Single-Line Diagrams/Schematics .................................................. 160
19.3 Fault Finding Procedures ..................................................................... 161
19.4 Software Faults and Related Issues ........................................................... 162
Chapter 20 Roles and Responsibilities ............................................................. 163
20.1 Introduction ................................................................................. 163
20.2 Captain/Master ............................................................................... 163
20.3 Senior DP Operator (SDPO)/ DP Operator (DPO) ................................................. 163
20.4 Chief Engineer ............................................................................... 164
20.5 Engineer of the Watch ........................................................................ 164
20.6 Electrical Technical Officer (ETO) ........................................................... 164
20.7 DP Training for Engineers and ETOs ........................................................... 165
Glossary and Abbreviations Used in Dynamic Positioning ............................................ 167
Bibliography ...................................................................................... 171
Index ............................................................................................. 173