AuXILIARY SYSTEMS IN hvdc OFFSHORE PLATFORMS

Post on 19-Oct-2021

45 views 1 download

Transcript of AuXILIARY SYSTEMS IN hvdc OFFSHORE PLATFORMS

Karl Gebrael

TU Braunschweig

June 26, 2019

Photo by Antony Hansen

Summary

• Production Line Overview

• THE Platform

• Systems of an Offshore HVDC Platform

• Integrated Control and Monitoring System• Function

• Subsystems

• Architecture

• Automation Concept

• Operation Levels

• Automation System Components

• Automation Hardware

• Redundancy

• Fire Fighting System• System Architecture

• Operation Philosophy

• Fire Detection Components

• Water Fire Fighting System

• Inert Gas System

• Heating, Ventilation, and Air Conditioning • Function

• Components

• Sea Water System

• Hypochlorite Plant

• Fresh Water Cooling System

• Centralized Chilled Water Cooling

• Chilled Water Freeze Plant

• Ducting in HVDC rooms

Production Line Overview

THE Platform

Cooling

•HVAC

•Sea Water

•Fresh Water Lighting and

power

communication

•CCTV

•PAGA

•Telephone

•Radio

•Internet Network

Protection•Fire detection

•Fire Fighting

Platform

•Structure

•Accommodation

•Drains

•Marine systems

•Helideck

Power

•Fuel system

•Diesel Generators

•Distribution transformers

•Switchboard

•UPS (230VAC and 110VDC)

ICMS

HVDC Converter

TransformersGISReactorsProtection & ControlSCADA

Systems of an Offshore HVDC Platform

Integrated Control and Monitoring System

ICMS - Function

• Main automation system on the platform

• Consists of 5 different subsystems in 5 automation areas

• Fully redundant – single fault tolerant

• Allows remote access from onshore stations

• Security: authorized access, firewall configuration, antivirus software

ICMS - Subsystems

IMAC

• Drain system

• Fuel system

• Instrument air compressor

• Potable water (RO, UV, calorifier)

• Sewage treatment

• Monitoring systems (telephone, CCTV, PAGA…)

• Marine systems (nav. Aids, AIS, helideck lighting…)

PMS

• MV switchboard

• premagnetization

• LV switchboard

• Distribution transformers

• Emergency switchboard

• UPS

HVAC

• HVAC technical rooms

• HVAC accommodation

• Sea water system

• Fresh water system

• Hypochlorite package

FIFI

• Fire detection system

• Gas detection system

• Fire water pumps

• Gas extinguishing areas

ESD

• Emergency shutdown

• Process shutdown

• Man Over Board

ICMS - Architecture

ICMS - Automation Concept

• 1st level: Platform automation system, handles the platform auxiliary systems

• 2nd level: SCADA system, handles the HVDC system, visualizes and operates the auxiliary systems

ICMS - Operation Levels

• Local control: directly at the equipment itself (pump, fan…)

• Station control – manual: subsystem is operated on SCADA operator station via screen commands, status is indicated on the screen

• Station control – automatic: subsystem is operated automatically depending on detected status via PLC, status is indicated on the screen

• Remote control: limited commands and statuses via IEC 60870-5-104. main operation for the 10kV platform supply.

ICMS - Automation System Components

• Control cabinets

• Server cabinets

• Engineering station

• Remote input/output cabinets

• Cables (FO, copper…)

• Field transmitters and actuators

• Package PLC/RTU

ICMS - Automation Hardware

• Power supply:

• chopper units with redundancy modules – redundant stabilized 24VDC

• Control:

• CPU with synchronization modules – fault-tolerant and fail-safe

• Ethernet card – allows the connection to industrial ethernet

• Distributed I/O DP slave – consists of IM and I/O cards

• Communication:

• Industrial ethernet switches – distributed to establish the ICMS network

• Optical/electrical converters – connect the distribution FO cables to the copper cables inside the cabinet

• Y-link – used to connect I/O devices with one DP interface to a redundant system

ICMS - Automation Hardware

ICMS - Redundancy

• Control

• 2 CPUs for each subsystem – in different locations

• Power supply

• 2 110VDC supply for each cabinet – different UPS – different cable routing

• 2 110V/24VDC power supply units with redundancy module

• Communication

• Double Profibus-DP ring (FO)

• 2 optical/electrical converters (FO to RS485)

• 2 I/O interface modules

Fire Fighting System

FiFi - System Architecture

FiFi –Operation Philosophy

FiFi - Fire Detection Components

Smoke detectors

optical type

based on the light scattering principle

flaming fires due to the combustion of

liquid or solid materials.

common spaces, corridors, mechanical

rooms…

IR Flame detectors

Hot carbon dioxide in a specific flame

wavelength

rooms with chemical storage (fuel tanks, diesel generators,

paint store)

Linear heat

detectors

Change of the resistance of

electrical conductor due to rise in temperature

Transformers rooms

Gas detectors

Electrochemical, infrared, MOS

For H2 and SF6

Hypochlorite and battery rooms

GIS rooms

Aspiration smoke

detectors

Pipe network with holes, aspirator, filter

and detection chamber

Critical rooms: converter,

transformer, GIS, reactor, generator

FiFi - Water Fire fighting Systems

• Redundant tanks and pumps system in separate rooms

• Normally supplied from fresh water system

• In case of depletion of fresh water, sea water bypass can be used

• Each tank is designed to supply the largest single fire scenario for 30 mins

• Jockey pumps are provided to maintain constant pressure in the system

FiFi - Water Fire fighting Systems

Foam

Used in transformer rooms

Activated manually or by heat detection

system

Sprinkler

Used in the accommodation and

office spaces

Activated manually, or by smoke detectors

Hydrants

Installed on helideck, accommodation, stores, machinery

spaces…

Fire water pump automatically runs when a hydrant is

activated

Water mist

Used in generator rooms

Activated manually, by flame and smoke

detectors

DIFFS

Installed on the helideck,

automatically pop up when pressurized

Activated manually, or by flame detectors

FiFi - Inert Gas System

• Non-liquefied inert gas (nitrogen) reduces oxygen content in the extinguishing zone

• 80l 300bar bottles stored in temperature controlled room

• Bottles grouped in combinations depending on extinguishing zones sizes

• HVDC and auxiliary transformer rooms and control rooms protected

• Extinguishing zones must be air-tight

• Operated by fire alarm, manual call point, ICMS.

Inert Gas Operation

Heating, Ventilation, and Air Conditioning

HVAC - Function

• dissipate the heat generated by HVDC equipment

• Ensure cooling of packages, such as ADG

• Provide fresh air for working areas

• Provide climate control for the accommodation

• React in case of fire to cut oxygen supply then flush the affected zones

HVAC - Components

• Sea water system

• Hypochlorite plant

• Fresh water cooling system

• Chilled water cooling system

• Chilled water freeze plant

• Ventilation system

HVAC - Sea Water System

• 4 lines, 2 groups

• Each line consists of 1 lift pump, 1 filter, 1 heat exchanger, and a connection to return line

• Multistage submersible Pump installed in well casing -16m MSL

• Filter is self-cleaning, removes particles bigger than 200m

• Heat exchanger is provided with provision for back flushing

• Automatic changeover happens in case of failure on one line, or if the running hours match 32 hrs or 24hrs

• Grouping ensures symmetrical electrical load and operating hours control

• SW system supplies potable water, sewage, deck wash, and fire fighting

HVAC - Hypochlorite plant

• Sodium hypochlorite is used as anti-fouling agent for prevention and control of marine growth

• Generated in situ from sea water

• Continuous dosing of 2ppm, shock dosing of 5ppm every 8hrs

• Excess can damage the SDSS material

• Package consists of booster pumps, rectifiers, electrolyzers, storage, dosing pump

• The hypochlorite room is protected by H2 gas detection

HVAC - Fresh Water Cooling System

• Provides multiple systems with cooling capacity:

• Transformers

• Converter cooling skid

• Auxiliary generators

• HVAC system

• Compensation reactor

• Outlet temperature is controlled by a 3-way control valve at the outlet of HE

HVAC - Centralized Chilled Water Cooling

• Produces and distributes chilled water to FCUs

• Consists of chillers and distribution pumps

HVAC - Chilled Water Freeze Plant

• Standalone plant

• Used for provision cooling room

Ducting in HVDC rooms

• Ducts shall not have sharp edges as it may cause partial discharge

• Rectangular ducts are acceptable with round edges

• All maintainable parts (dampers, sensors…) to be installed outside the HVDC rooms

• All bolts and nuts to be of locked type

• All ducting to be earthed

• All ducting to be outside of air clearance

• Air supply from below the converters and exhaust above them

Photo by Antony Hansen