BSI PD IEC/TS 62600-2:2016
$215.11
Marine energy. Wave, tidal and other water current converters – Design requirements for marine energy systems
| Published By | Publication Date | Number of Pages |
| BSI | 2016 | 106 |
1.1 General
This part of IEC 62600 provides the essential design requirements to ensure the engineering integrity of wave, tidal and other water current energy converters, referred to as marine energy converters (MECs), for a specified design life. Its purpose is to provide an appropriate level of protection against damage from all hazards that may lead to failure of the primary structure, defined as the collective system comprising the structural elements, foundation, mooring and anchors, piles, and device buoyancy designed to resist global loads.
This document includes requirements for subsystems of MECs such as control and protection mechanisms, internal electrical systems, mechanical systems and mooring systems as they pertain to the structural viability of the device under site-specific external environmental conditions. This document applies to wave, tidal and other water current converters and to structures that are either floating or fixed to the seafloor or shore. This document applies to structures that are unmanned during operational periods.
This document addresses site-specific conditions, safety factors for critical structures and structural interfaces, external load cases (including extreme load magnitude, duration, and frequency), failure probability and failure consequences for critical structures and structural interfaces (overall risk assessment), and failsafe design practices (demonstration of adequate redundancy). The effect of subsystem failure on the primary structure is also addressed.
This document does not address the effects of MECs on the physical or biological environment (unless noted by exception). This document is used in conjunction with the appropriate IEC and ISO standards, as well as regional regulations that have jurisdiction over the installation site.
1.2 Applications
This document is applicable to MEC systems designed to operate from ocean, tidal and river current energy sources, but not systems associated with hydroelectric impoundments or barrages. This document is also applicable to wave energy converters. It is not applicable to ocean thermal energy conversion (OTEC) systems or salinity gradient systems.
Although important to the overall objectives of the IEC 62600 series, this document does not address all aspects of the engineering process that are taken into account during the full system design of MEC systems. Specifically, this document does not address energy production, performance efficiency, environmental impacts, electric generation and transmission, ergonomics, or power quality.
This document, to the extent possible, adapts the principles of existing applicable standards already in use throughout the marine industry (structure, moorings, anchors, corrosion protection, etc.) and by reference, defers to the appropriate international documents. This document adheres to a Load Resistance Factor Design (LRFD) approach and the principles of limit state design as described in ISO 2394 .
MECs designed to convert hydrokinetic energy from significant hydrodynamic forces into other forms of usable energy, such as electrical, hydraulic, or pneumatic may be different from other types of marine structures. Many MECs are designed to operate in resonance or conditions close to resonance. Furthermore, MECs are hybrids between machines and marine structures. The control forces imposed by the power takeoff (PTO) and possible forces from faults in the operation of the PTO distinguish MECs from other marine structures.
The goal of this document is to adequately address relevant design considerations for MECs that have progressed to an advanced prototype design stage or beyond. This refers to technology concepts that have been proven either through analysis, open water test data, scale model testing in tanks or dry land test facilities, and that are ready for commercialization. It is anticipated that this document will be used in certification schemes for design conformity.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 4 | CONTENTS |
| 10 | FOREWORD |
| 12 | INTRODUCTION |
| 13 | 1 Scope 1.1 General 1.2 Applications |
| 14 | 2 Normative references |
| 15 | 3 Terms and definitions 4 Symbols and abbreviated terms |
| 17 | 5 General considerations 5.1 General 5.2 Regulations 5.3 Suitability and/or relevance of standards 5.4 Quality assurance and quality control |
| 18 | 5.5 Safety levels Tables Table 1 – Safety levels |
| 19 | 5.6 Design principles – structure and foundations 5.7 Load definition and load combinations |
| 20 | 5.8 Other considerations 5.8.1 Stability and watertight integrity 5.8.2 Electrical, mechanical, instrumentation and control systems 5.8.3 Reliability issues 5.8.4 Corrosion protection 5.8.5 Design for operation, inspection, maintenance and decommissioning 5.9 Operational and structural resonance |
| 21 | 5.10 Basis of design 6 External conditions 6.1 General 6.2 Waves 6.2.1 Normal sea state (NSS) 6.2.2 Normal wave height (NWH) |
| 22 | 6.2.3 Extreme sea state (ESS) 6.2.4 Extreme wave height (EWH) |
| 23 | 6.2.5 Breaking waves 6.2.6 Wave run-up 6.3 Sea currents 6.3.1 General 6.3.2 Sub-surface currents |
| 24 | 6.3.3 Wind-generated near-surface currents 6.3.4 Tidal currents 6.3.5 Breaking wave-induced surf currents |
| 25 | 6.3.6 Normal current model (NCM) 6.3.7 Extreme current model (ECM) 6.3.8 Normal turbulence model (NTM) 6.3.9 Extreme turbulence model (ETM) |
| 26 | 6.4 Wind conditions 6.5 Water level 6.5.1 General Figures Figure 1 – Definition of water levels (see IEC 61400-3) |
| 27 | 6.5.2 Normal water level range (NWLR) 6.5.3 Extreme water level range (EWLR) 6.6 Sea and river ice |
| 28 | 6.7 Earthquakes 6.8 Marine growth 6.9 Seabed movement and scour 6.10 Ship collisions 6.11 Other environmental conditions 7 Loads and load effects 7.1 General 7.2 Loads |
| 29 | Table 2 – Types of loads that shall be considered |
| 30 | 7.3 Design situations and load cases 7.3.1 General 7.3.2 Interaction with waves, currents, wind, water level and ice |
| 31 | 7.3.3 Design categories 7.3.4 Limit states Table 3 – ULS combinations of uncorrelated extreme events Table 4 – Design categories |
| 32 | 7.3.5 Partial safety factors |
| 33 | 7.3.6 Simulation requirements Table 5 – ULS partial load safety factors γf for design categories |
| 34 | 7.3.7 Design conditions |
| 35 | Table 6 – Design load cases for WEC |
| 37 | Table 7 – Design load cases for TEC |
| 42 | 8 Materials 8.1 General |
| 43 | 8.2 Material selection criteria |
| 44 | 8.3 Environmental considerations 8.4 Structural materials 8.4.1 General 8.4.2 Metals |
| 45 | 8.4.3 Concrete 8.4.4 Composites |
| 46 | Table 8 – ISO test standards |
| 47 | 8.5 Compatibility of materials 9 Design of primary structures for wave and tidal/current energy converters 9.1 General 9.2 Design of steel structures 9.2.1 General |
| 48 | 9.2.2 Load and resistance factor design (LRFD) 9.2.3 Ultimate limit state Table 9 – Material factors γM for buckling |
| 49 | 9.2.4 Fatigue limit state 9.2.5 Serviceability limit state 9.3 Design of concrete structures 9.3.1 General 9.3.2 Limit states |
| 50 | 9.3.3 Bending moment and axial force 9.3.4 Slender structural members 9.3.5 Transverse shear 9.3.6 Torsional moments 9.3.7 Bond strength and anchorage failure 9.3.8 Fatigue limit state |
| 51 | 9.3.9 Serviceability limit state 9.3.10 Stresses in pre-stressed reinforcement 9.3.11 Stresses in concrete 9.3.12 Detailing of reinforcement 9.3.13 Corrosion control 9.4 Design of grouted connections 9.4.1 General 9.4.2 Design principles 9.5 Design of composite structures 9.5.1 General |
| 52 | 9.5.2 Design principles |
| 54 | 9.5.3 Joints and interfaces 10 Electrical, mechanical, instrumentation and control systems 10.1 Overview 10.2 General requirements Table 10 – Summary of model factors |
| 55 | 10.3 Abnormal operating conditions safeguard |
| 56 | 11 Mooring and foundation considerations 11.1 Overview 11.1.1 General 11.1.2 Unique challenges for wave energy converters 11.1.3 Unique challenges for tidal energy converters 11.2 Tethered floating structures |
| 57 | 11.3 Fixed structures 11.4 Compound MEC structures |
| 58 | Figure 2 – Examples of compound position mooring systems for wave (a, b) and tidal (c, d) energy conversion systems |
| 59 | 12 Inspection requirements 12.1 General 12.2 Consideration during the design stage |
| 60 | 12.3 Inspection and maintenance planning 12.4 Data management |
| 61 | 12.5 Condition assessment and integrity evaluation (against performance requirements) 12.6 Maintenance execution |
| 62 | 13 Life cycle considerations 13.1 General |
| 64 | 13.2 Planning 13.2.1 General 13.2.2 Installation conditions 13.2.3 Site access 13.2.4 Environmental conditions |
| 65 | 13.3 Documentation 13.4 Receiving, handling and storage 13.5 Assembly of and installation of MECs 13.5.1 General |
| 66 | 13.5.2 Access 13.6 Fasteners and attachments 13.7 Cranes, hoists and lifting equipment 13.8 Decommissioning |
| 68 | Annexes Annex A (normative) Load definition and load combinations A.1 Load combinations |
| 69 | A.2 Load calculations |
| 71 | A.3 Floating and moored devices A.4 Flow analysis methodology |
| 73 | Annex B (normative) Reliability issues B.1 General B.2 Structure and foundation B.3 Mechanical system |
| 74 | B.4 Electrical system B.5 Control and protection system B.6 Instrumentation B.7 Testing during qualification |
| 75 | Annex C (normative) Corrosion protection C.1 General C.2 Steel structures C.2.1 General Figure C.1 – Profile of the thickness loss resulting from corrosion of an unprotected steel structure in seawater (1 mil = 0,025 4 mm) |
| 76 | C.2.2 Corrosion rates C.2.3 Protective coatings C.3 Cathodic protection C.3.1 General |
| 77 | C.3.2 Closed compartments C.3.3 Stainless steel C.4 Concrete structures C.4.1 General C.4.2 Provision of adequate cover |
| 78 | C.4.3 Use of stainless steel or composite reinforcement C.4.4 Cathodic protection of reinforcement C.5 Non-ferrous metals |
| 79 | C.6 Composite structures C.7 Compatibility of materials C.8 Chains, steel wire and fibre rope |
| 80 | Annex D (normative) Operational and structural resonance D.1 General D.2 Control systems D.3 Exciting frequencies D.4 Natural frequencies |
| 81 | D.5 Analysis D.6 Balancing of the rotating components |
| 82 | Annex E (informative) Requirements for a basis of design E.1 General |
| 83 | Figure E.1 – Quality assurance system |
| 84 | E.2 Design life E.3 Design standards E.4 Regional regulations E.5 Environmental conditions E.5.1 General E.5.2 Meteorology and climatology E.5.3 Air/water conditions |
| 85 | E.5.4 Water level E.5.5 Currents E.5.6 Waves E.5.7 Marine life E.6 Seabed conditions E.6.1 General E.6.2 Bathymetry and coastal topography |
| 86 | E.7 Material standards and testing |
| 87 | Annex F (informative) Wave spectrum F.1 Overview F.2 The Pierson-Moskowitz spectrum |
| 88 | Figure F.1 – PM spectrum |
| 89 | Figure F.2 – JONSWAP and PM spectrums for typical North Sea storm sea state |
| 90 | F.3 Relationship between peak and zero crossing periods F.4 Wave directional spreading |
| 91 | Annex G (informative) Shallow water hydrodynamics and breaking waves G.1 Selection of suitable wave theories Figure G.1 – Regions of applicability of stream functions, stokes V, and linear wave theory |
| 92 | G.2 Modelling of irregular wave trains G.3 Breaking waves |
| 93 | Figure G.2 – Breaking wave height dependent on still water depth |
| 94 | Figure G.3 – Transitions between different types of breaking waves as a function of seabed slope, wave height in deep waters and wave period |
| 95 | Annex H (informative) Guidance on calculation of hydrodynamic loads H.1 General Figure H.1 – Relative importance of mass, viscous dragand diffraction forces on marine structures |
| 96 | H.2 Large bodies H.3 Hybrid structures |
| 97 | H.4 Short term statistics H.5 Breaking wave loads |
| 98 | H.6 Dynamic loads due to turbulent flow |
| 99 | Bibliography |
