- TB 675 2017 B4-61 General guidelines for HVDC electrode design
- TB 671 2016 B4-62 Connection of wind farms to weak AC networks
- TB 663 Guidelines for the procurement and testing of STATCOMS
- TB 657 2016 Guidelines for the preparation of "connection agreements" or "Grid Codes" for multi-terminal schemes and DC Grids
- TB 649 2016 GUIDELINES FOR LIFE EXTENSION OF EXISTING HVDC SYSTEMS
- TB 619 2015 HVDC CONNECTION OF OFFSHORE WIND POWER PLANTS
- TB 617 2015 HVDC LCC Converter Transformers - CONVERTER TRANSFORMER FAILURE SURVEY RESULTS FROM 2003 TO 2012
- TB 609 2015 Study of Converter Transients Imposed on the HVDC Converter Transformers
- TB 604 2014 Guide for the Development of Models for HVDC Converters in a HVDC Grid
- TB 590 2014 B4-04 Protocol for reporting the operational performance of HVDC Transmission Systems
- TB 563 2013 B4-38 Modelling and Simulation Studies to be performed during the lifecycle of HVDC Systems
- TB 554 2013 B4-49 Performance Evaluation and Applications Review of Existing Thyristor Control Series Capacitor Devices – TCSC
- TB 553 2013 B4-47 Special Aspects of AC Filter Design for HVDC Systems
- TB 536 2013 C4/B4/C1.604 Influence of Embedded HVDC Transmission on System Security and AC Network Performance
- TB 533 2013 B4-52 HVDC Grid Feasibility Study
- TB 508 2012 B4-44 HVDC Environmental Planning Guidelines
- TB 492 2012 B4-46 Voltage Source Converter (VSC) HVDC for Power Transmission - Economic Aspects and Comparison with other AC and DC Technologies
- TB 447 2011 B4-48 Components Testing of VSC System for HVDC Applications
- TB 417 2010 B4-45 Technological Assessment of 800kV HVDC Applications
- TB 407 2010 JWG A2/B4.28 HVDC Converter Transformers - Guidelines for conducting design reviews for HVDC converter transformers
- TB 406 2010 JWG A2/B4.28 HVDC Converter Transformers - Design review, test procedures, ageing evaluation and reliability in service
- TB 388 2009 JWG B2/B4/C1.17 IMPACTS OF HVDC LINES ON THE ECONOMICS OF HVDC PROJECTS
- TB 371 2009 WG B4.40 Static Synchronous Series Compensator (SSSC)
- TB 370 2009WG B4.39 Integration of large Scale Wind Generation using HVDC and Power Electronics
- TB 364 2008 WG B4.41 Systems with multiple DC Infeed
- TB 352 2008 WG B4.34 Capacitor Commutated Converted (CCC) HVDC Interconnections: Digital modeling and Benchmark Circuit
- TB 337 2007 JWG B4/A3/B3.43 Increased System Efficiency by Use of New Generations of Power Semiconductors
- TB 280 2005 SC B4 WG B4.33 HVDC and FACTS for distribution systems
- TB 269 2005 SC B4 WG B4.37 VSC Transmission
- TB 242 2004 SC B4 WG B4.35 Thyristor controlled voltage regulators: Parts 1 and 2
- TB 240 2004 SC B4/A2 JTF B4.04/A2.01 Analysis of HVDC thyristor converter transformer performance
- TB 237 2003 SC B4 WG B4.19 Static synchronous compensator (STATCOM) for arc furnace and flicker compensation
- TB 223 2003 SC B4 WG B4.28 Active filters in HVDC applications
- TB 222 2003 SC B4 WG B4.05 On voltage and power stability in AC/DC systems
- TB 215 2002 SC 14 WG 14.32 HVDC converter stations for voltages above +/- 600 kV
- TB 205 2002 SC 14 WG 14.31 Custom power - State of the art.
- TB 202 2002 SC 14 WG 14.26 HVDC stations audible noise
- TB 186 2001 SC 14 WG 14.20 Economic assessment of HVDC links
- TB 183 2001 SC 14/37/38/39 JWG 14/37/38/39.24 FACTS technology for open access
- TB 160 2000 SC 14 WG 14.27 Unified power flow controller (UPFC)
- TB 149 1999 SC 14 WG 14.29 Coordination of controls of multiple FACTS/HVDC links in the same system.
- TB 144 1999 SC 14 WG 14.19 Static synchronous compensator (STATCOM)
- TB 143 1999 SC 14 WG 14.25 Cross-modulation of harmonics in HVDC schemes
- TB 139 1999 SC 14 WG 14.30 Guide to the specification and design evaluation of AC filters for HVDC systems.
- TB 136 1999 SC 14 TF 14.01.04 Fire aspects of HVDC thyristor valves and valve halls.
- TB 130 1998 SC 14 WG 14.23 Operational guidelines and monitoring of HVDC systems
- TB 127 1998 SC 14 WG 14.11 Guide for upgrading transmission systems with HVDC transmission
- TB 123 1997 SC 14 WG 14.18 Thyristor controlled series compensation
- TB 119 1997 SC 14 WG 14.05 Interaction between HVDC convertors and nearby synchronous machines.
- TB 116 1997 SC 11/14 JWG 11/14.09 Guide for preliminary design and specification of hydro stations with HVDC unit connected generators.
- TB 115 1997 SC 14 WG 14.07 Guide for planning DC links terminating at AC system locations having low short-circuit capacities. Part II : Planning guidelines.
- TB 114 1997 SC 13/14 WG 13/14.08 Circuit-breakers for meshed multiterminal HVDC system.
- TB 113 1997 SC 14 WG 14.01.03 Test circuits for HVDC thyristor valves.
- TB 112 1997 SC 14 WG 14.17 Semiconductor power devices for use in HVDC and FACTS controllers.
- TB 103 1996 SC 14 WG 14.05 Commutation failures. Causes and consequences.
- TB 097 1995 SC 14 WG 14.12 System tests for HVDC installations.
- TB 093 1995 SC 14 WG 14.01.02 Guidelines for testing of thyristor valves for static var compensators.
- TB 092 1995 SC 14 WG 14.03.02 DC side harmonics and filtering in HVDC transmission systems
- TB 086 1994 SC 33 /21/14 JWG 33/21/14.16 Overvoltages on HVDC cables.
- TB 082 1994 SC 38 WG 38.01.05 Use of DC converters for VAR control.
- TB 078 1994 SC 14 WG 14.01.02 Voltage and current stresses on thyristor valves for static var compensators.
- TB 077 1993 SC 38 WG 38.05.04 Analysis and optimisation of SVC use in transmission systems.
- TB 068 1992 SC 14 WG 14.07 Guide for planning DC links terminating at AC locations having low short-circuit capacities. Part 1. AC/DC interaction phenomena.
- TB 065 1992 SC 14 WG 14.03 AC harmonic filters and reactive compensation for HVDC with particular reference to noncharacteristic harmonics.
- TB 051 1996 SC 38 WG 38.01.06 Load flow control in high voltage systems using FACTS controllers.
- TB 034 1989 SC 33/14 JWG 33/14.05 Guidelines for the applications of metal oxide arresters without gaps for HVDC converter stations.
- TB 025 1986 SC 38 TF 38.01.02 Static var compensators.
- TB 003 1987 SC 14 WG 14.04 Compendium of HVDC schemes throughout the world.
- TB 000 1994 SC 14 WG 14.02 A summary of the report on survey of controls and control performance in HVDC schemes.
- Session papers
- Other Documents
- SC Library
- Documents related to the development of HVDC Grids
TB 675 2017 B4-61 General guidelines for HVDC electrode design
HVDC electrodes have traditionally been installed on HVDC transmission systems to provide a low resistance current return path during both monopolar and bipolar operation using the earth and/or sea as the conductive medium. HVDC electrodes are in general less costly and have lower losses than dedicated metallic return conductors. Environmental concerns related to electrode operation have become more prominent in recent years due to greater public awareness of potential impacts, tighter environmental approval processes and increasing numbers of HVDC projects. While the environmental approval process can be challenging, the long-time successful operation of older electrodes indicates many of the potential environmental impacts from electrodes can be minimized or eliminated either by suitable selection of the electrode site for impacts remote from the electrode or by application of good design techniques if the impacts are near the electrode or on the electrode site. With the development of new geophysical and geological investigation techniques, and more powerful computer simulation tools for electrical field studies and infrastructure modelling, potentially more economical designs of ground electrodes can be achieved, and the impacts of the electrode operation on existing or potential future infrastructure can be more accurately quantified. This technical brochure is prepared to formalize methodology and guidelines for the analysis, design, construction and testing of new electrodes and refurbishment or extension of existing electrodes. It is a collection of most recent techniques, processes and descriptions of software and procedures available for site selection and electrode designs.
TABLE OF CONTENTS
TERMS AND DEFINITIONS
1. HVDC CONFIGURATIONS WITH GROUND RETURN CURRENT
2. TYPES OF ELECTRODES AND SELECTION OF TYPE OF ELECTRODE
2.1 TYPES OF ELECTRODES
2.2 ELECTRODE SHAPES AND CONFIGURATIONS
2.2.1 Land Electrodes
2.2.2 Sea Electrodes
2.2.3 Beach Electrodes
2.2.4 Pond Electrodes
2.3 SELECTION OF ELECTRODE TYPE
3. ELECTRODE SITE SELECTION CRITERIA AND PROCESS
3.1 GENERAL ASPECTS OF SITE SELECTION
3.1.1 Process of Finding Candidate Electrode Locations
3.1.2 Site Exclusion Process
3.2 TECHNICAL, ECONOMIC AND TIME ASPECTS OF SITE SELECTION
3.2.1 Duration of Operation in Monopolar Mode
3.2.2 Rated and Overload current
3.2.3 Converter Station Locations
3.2.4 Line Servitudes or Right-of-way and Land Acquisition
3.2.5 Environmental and Other Permits
3.2.6 Possible Impact on Infrastructure
3.2.7 Constructability and Accessibility
3.2.8 Permitted Potentials and Potential gradients
3.3 GEOPHYSICAL, GEOLOGICAL AND HYDROLOGICAL ASPECTS OF SITE SELECTION
3.3.1 Land Electrodes
3.3.2 Sea and Shore electrodes
3.4 PROCESS OF GEOPHYSICAL AND GEOLOGICAL INVESTIGATIONS
3.4.1 Geoscientific Desktop Study and Definition of Candidate Areas
3.4.2 Initial Resistivity Model
3.4.3 Initial Field Investigations
3.4.4 Site Selection
3.4.5 Permitting, Land Acquisition, Line Servitudes
3.4.6 Detailed Field Investigations
3.4.7 Detailed Resistivity Model
3.4.8 Preliminary Design and Electrode Modelling
3.4.9 Borehole Investigations
3.4.10 Test Electrodes
4. IMPACTS OF ELECTRODES
4.2 IMPACTS ON INFRASTRUCTURE
4.2.1 Impacts on Buried Metallic Objects
4.3 IMPACTS ON THE ENVIRONMENT
4.3.1 Compass Deflection
4.3.2 Chemical Aspects
4.4 IMPACT STUDIES
4.4.1 Data for Impact Studies
4.4.2 Physical Variables to Study
5. ELECTRODE DESIGN ASPECTS
5.1 GENERAL DESIGN CONSIDERATIONS
5.1.1 Safety Requirements for Humans and Animals
5.1.2 Safety Metrics and Criteria
5.1.3 Physical design criteria and constraints
5.1.4 Potential Impacts on Environment and Infrastructure
5.1.6 Data Required for design
5.2 DESIGN METHODOLOGY
5.2.1 Simple Calculations
5.2.3 Verification of Design
5.3 LAND ELECTRODES
5.3.1 Design Considerations
5.3.2 Operation and Maintenance Considerations
5.3.3 Land Electrode Design Example
5.4 SEA ELECTRODES
5.4.1 Design Considerations
5.4.2 Operation and Maintenance Considerations
5.4.3 Environmental Impact
5.4.4 Chemical Aspects
5.4.5 Structure and Features
5.4.6 Electrode active element materials
5.4.7 Sea Electrode Designs
5.4.8 Sea Electrodes in Operation
5.5 SHORELINE POND ELECTRODES
5.5.1 Design Consideration
5.5.2 Operation and Maintenance Considerations
5.5.3 GPR, Potential Gradient and Resistance to Remote Earth
5.5.4 Pond Electrode Examples
5.6 SHORELINE BEACH ELECTRODES
5.6.1 Design considerations
5.6.2 Beach Electrode Example
6. CONNECTION FROM CONVERTER STATION TO ELECTRODE STATION
6.1 OVERHEAD ELECTRODE LINES
6.2 CABLE ELECTRODE LINE
6.3 DESIGN FACTORS FOR OVERHEAD ELECTRODE LINES
6.3.1 Factors which affect the overhead electrode line
6.3.2 Environmental Impact of Overhead Electrode Lines
6.4 ELECTRODE LINE MONITORING AND PROTECTION
6.5 MAINTENANCE OF ELECTRODE LINES AND CABLES
7. AUXILIARY SYSTEMS FOR ELECTRODE STATIONS
7.2 STATION SERVICE SUPPLY
7.3 ELECTRODE SITE MONITORING SYSTEM
7.4 FENCES, EQUIPMENT AND CONTROL BUILDINGS
8. TESTING AND COMMISSIONING
8.1 LAND ELECTRODE
8.1.1 Soil Temperature
8.1.2 Soil Moisture
8.1.3 Resistance Measurements
8.1.4 Sub Electrode Resistance
8.1.5 Current Distribution Measurements
8.1.6 Potential and Gradient Measurements
8.1.7 Test of Data Acquisition System
8.1.8 DC Current in Converter or Power Transformer Neutrals
8.2 SEA ELECTRODES
8.3 SHORELINE POND ELECTRODES
8.4 SHORELINE BEACH ELECTRODES