Share

TB 417 2010 B4-45 Technological Assessment of 800kV HVDC Applications

Studies carried out by the WG and work being carried out by manufacturers show that no major problem is anticipated with the implementation of 800kVdc HVDC technology,considered techno-economical where large amounts of power is to be transmitted over long distances. The test levels specified in this TB should be beneficial to utilities and manufacturers and should streamline the requirements of testing and test values.

 Download TB from ecigre website  

TABLE OF CONTENTS

1.0 INTRODUCTION

      1.1 Technology status and development

      1.1.1 Converter configuration and rating

      1.1.2 Ground electrodes

      1.1.4 Insulation co-ordination & Insulation levels

      1.1.5 Interference levels

      1.1.6 Control, Protection and Communication

      1.1.7 Reliability and availability

      1.1.8 Pollution and altitude aspects

      1.1.9 Transmission line design

      1.1.10 Station layout

      1.1.11 Test requirements

2.0 SCOPE OF THE WORKING GROUP

3.0 TECHNOLOGY STATUS AND DEVELOPMENT

      3.1 Converter transformers (including their bushings)

      3.2 Valves and valve halls

      3.3 Wall bushings

      3.4 High speed by-pass switches

      3.5 High speed paralleling and de-paralleling switches

      3.6 High speed DC neutral switches

      3.7 DC isolators

      3.8 Smoothing reactors

      3.9 DC capacitors in DC harmonic filters

      3.10 DC capacitors in DC PLC and RI filters

      3.11 DC voltage dividers (DCVD)

      3.12 DC surge arresters

      3.13 800 kVDC post insulators

      3.14 800 kVDC Test circuit

      3.15 AC switchyard

4.0 CONVERTER CONFIGURATION AND RATING

      4.1 A bipole with one single converter per pole

      4.2 A bipole with two series converters per pole

      4.3 A bipole with two parallel converters per pole

      4.4 Transmission power larger than 6000 MW

      4.5 Neutral Bus configurations

5.0 GROUND ELECTRODE 

      5.1 System considerations

      5.2 Reliability considerations

      5.3 Interference considerations

      5.4 Design Criteria

      5.5 Geophysical Methods

            5.5.1 Survey Design

            5.5.2 Electrode Line Design

6.0 REACTIVE COMPENSATION AND AC SYSTEM REQUIREMENTS

      6.1 Reactive power absorbed by the converters

      6.2 Reactive power compensation

      6.3 Net reactive power interchange with the AC system

      6.4 Limits on Reactive Power Interchange

      6.5 Temporary Over-voltage Conditions

      6.6 AC System Conditions

            6.6.1 Sending End

            6.6.2 Receiving End

      6.7 Issues related to 800 kV

7.0 INSULATION CO-ORDINATION

      7.1 Principles of HVDC insulation coordination

            7.1.1 Insulation coordination for 800 kV HVDC systems

            7.1.2 Converter Topology and Smoothing Reactor Arrangement

            7.1.3 Smoothing reactor arrangement

            7.1.4 Arrester arrangement

                  7.1.4.1 Converter transformer arresters type 'A2'

                  7.1.4.2 Converter group arrester type 'C1'

                  7.1.4.3 Converter group arrester type 'C2'

                  7.1.4.4 Mid-point arrester type 'M'

                  7.1.4.5 Smoothing reactor arrester type 'SR'

            7.1.5 Arrester Arrangement for Parallel Valve Group Converter

                  7.1.5.1 Converter transformer arresters type 'A2'

                  7.1.5.2 Converter group arrester type 'C'

                  7.1.5.3 Mid-point arrester type 'M'

                  7.1.5.4 Smoothing reactor arrester type 'SR'

            7.1.6 Insulation margins and withstand voltages

            7.1.7 External Insulation

            7.1.8 External Insulation of Outdoor DC Yard Equipment

                  7.1.8.1 Creepage distance

                  7.1.8.2 Shed form of housings

                  7.1.8.3 Corrections for altitudes

                  7.1.8.4 Minimum clearances / flashover distance

                  7.1.8.5 Height/length of the equipment

                  7.1.9 External Insulation of Indoor DC Yard Equipment

8.0 INSULATION LEVELS

      8.1 DC system parameters of two demonstration cases

      8.2 Converter Main Data for Series Valve Groups

      8.3 Converter Main Data for Parallel Valve Groups

      8.4 Indicative protective levels and withstand voltages

            8.4.1 Converter Station with Series Valve Groups

            8.4.2 Converter Station with Parallel Valve Groups

      8.5 Discussion of Insulation Levels

      8.6 Withstand and testing levels of 800 kV main equipment

            8.6.1 Converter Transformers

            8.6.2 Thyristor Valves

            8.6.3 Smoothing Reactors

            8.6.4 Wall Bushings

            8.6.5 800 kV DC Bus Equipment

9.0 INTERFERENCE LEVELS

      9.1 Purpose and Scope

      9.2 Comparison of Electrical Environment of AC & DC Transmission Lines

      9.3 Comparison of DC & AC Interference Effects

            9.3.1 Electric and Magnetic Fields

            9.3.2 Corona, Radio Interference (RI) & Audible Noise (AN)

      9.4 Survey of Literature Published By Scientific and Health Organisations

            9.4.1 WHO EHC

            9.4.2 Heath Council of Netherlands 

            9.4.3 ICNIRP

            9.4.4 German Standards (DIN)

      9.5 Survey of Technical Papers Related To HVDC Interference Effects

            9.5.1 Paper on Environmental Characteristics

            9.5.2 EPRI Report on HVDC Converter Stations for Voltages above 600 kV

            9.5.3 Operating experience from HVDC test lines and transmission lines

      9.6 Conclusion

      9.7 Recommendations

10.0 CONTROL AND PROTECTION

      10.1 Control System

            10.1.1 Operator Control Level

            10.1.2 Converter Control and Protection Level

            10.1.3 Field Level

      10.2 Operation Modes

      10.3 Provision for Master Control

      10.4 Control Concept

            10.4.1 Rectifier

            10.4.2 Inverter

      10.5 Control Functions

      10.6 Protection Functions

      10.7 Communication

            10.7.1 Power Line Carrier (PLC)

            10.7.2 Optical Fibre Ground Wire (OPGW)

            10.7.3 Microwave

            10.7.4 Satellite communication

            10.7.5 Telephone systems

      10.8 Control Issues related to 800 kV

11.0 AVAILABILITY AND RELIABILITY

      11.1 Review of some definitions

            11.1.1 Energy Availability (EA)

            11.1.2 Reliability

      11.2 Major areas affecting Availability / Reliability

      11.3 Overall Project Scheme

      11.4 Requirements of Integrated AC / DC System

      11.5 AC Switchyard Equipment

      11.6 Equipment common to bipolar system

      11.7 Electrode station design

      11.8 Converter Transformer

      11.9 Valve Hall

      11.10 DC Switchyard Equipment

      11.11 Control, Protection and communication requirement for both series and parallel converter groups

      11.12 Auxiliary systems

      11.13 Spares and maintenance

12.0. EXTERNAL INSULATION: POLLUTION AND ALTITUDE ASPECTS FOR DESIGN

      12.1. Flashover process

      12.2. Operation experience

      12.3. Site conditions and test station

      12.4. Laboratory tests

      12.5. Means of improving pollution performance

      12.6. Recommendations

            12.6.1 Surfaces

            12.6.2 Profiles

            12.6.3 Creepage distances

      12.7. Altitude correction

            12.7.1 Basic principles

            12.7.2 Air parameters

            12.7.3 Influence of air density

            12.7.4 G-factor methods

            12.7.5 Empirical proposal

            12.7.6 Simplified approaches

            12.7.7 Comparison of different correction methods and discussion

13.0 TRANSMISSION LINE DESIGN

      13.1 Transmission Line basic configurations

      13.2 Insulation Requirements

            13.2.1 Internal overvoltages

            13.2.2 Operating voltage

            13.2.3 Specific leakage distance for various HVDC lines

            13.2.4 Tower head and Pole spacing

            13.2.5 Lightning Performance

      13.3 Corona related considerations

            13.3.1 Conductor Surface Gradient

            13.3.2 Corona Losses

            13.3.3 Radio Interference and Audible Noise

      13.5 Choice of Conductor

14.0 LAYOUT OF CONVERTER STATION

      14.1 Function Blocks of Converter Stations

      14.2 Layout of Converter Area

      14.3 Layout of DC Yard

      14.4 Layout of AC Yard

      14.5 Layout of the Auxiliaries

      14.6 General Layout of the Station

15.0 TEST REQUIREMENT

      15.1 Basis of test requirements

      15.2 Test requirement of main 800 kV DC equipment

16.0 SUMMARY

      16.1 Transmitted power up to 6000 MW

            16.1.1 One single converter per pole

            16.1.2 Two converters in series

            16.1.3 Two parallel converters

      16.2 Transmitted power above 6000 MW

      16.3 Current status of 800 kV DC technology

      16.4 Conclusions