ASIR CPS EXTENSION PROJECT

PAGE TCE CONSULTING ENGINEERS LIMITED

i30421007-3DR-00007-P0BCONTROL PHILOSOPHYSHEET OF iOF 4

SAUDI ELECTRICITY COMPANY

EASTERN OPERATING AREA

Dammam, Saudi Arabia

GENERATION EXPANSION OF ARAR POWER PLANT

(CONTRACT NO : 30421007/00)

CONTROL PHILOSOPHY FOR

ARAR GENERATION EXPANSIONDOCUMENT NO. : 30421007-3DR-00007-P0B

JANUARY, 2005

ENGINEERING CONSULTANTTCE CONSULTING ENGINEERS LIMITED

73/1, ST. MARKS ROAD

BANGALORE 560 001

INDIA

CONTRACTOR:

AL-TOUKHI COMPANY FOR INDUSTRY & TRADING

P.O. BOX 497, RIYADH 11411, KINGDOM OF SAUDI ARABIA

TEL. 00966-1-4633660 : FAX. 00966-1-4631150

CONTENTSCLAUSE No.DESCRIPTIONPAGE No.

1.0INTRODUCTION1

2.0OBJECT2

3.0REFERENCES3

4.0CONTROL PHILOSOPHY FOR GENERATING PLANT

4

5.0CONTROL PHILOSOPHY FOR ELECTRICAL EQUIPMENT10

1.0 INTRODUCTION:

1.1 Al-Toukhi company for Industry & Trading has been awarded turnkey contract for Open Cycle Gas Turbine based CPS expansion project at Arar of Saudi Electric Company-Eastern Operation Area (SEC-EOA), Saudi Arabia.

1.2 The project consists of design, engineering, procurement, installation, testing and commissioning of two (2) Nos. 60.16MW @ 50(C, PG7121 (EA) model Gas Turbine Generator unit of GE make along with associated Generator Transformer and other balance of plant electro-mechanical equipment.

2.0 OBJECT:2.1The scope of this document is to describe the Control Philosophy for the proposed Power Plant to be installed at Arar Central power Station, Saudi Arabia.

3.0REFERENCE DOCUMENTS & STANDARDS

3.1Scope of work and Technical Specification PTS-1022

4.0CONTROL PHILOSOPHY FOR GENERATING PLANT

4.1The plant includes the following package Units:

GTG Control System

SOER System & Master clock

Fuel oil system

HVAC System

Fire fighting and fire detection/alarm system

Compressed Air System

Common Drainage System

4.2 The GT control system is fail safe and does not require Emergency shutdown control. Emergency shutdown pushbutton in remote control room shall be wired to each GT control system. 4.3 GTG UnitEach GTG unit is supplied with a Packaged Electric and Electronic Control compartment, which has a number of control and protection systems designed for a reliable and safe operation of the GTG units. The complete GTG control and protection will be as per GE standards. GTG control will be through a Local and a remote HMI. The remote HMI will be provided in the existing Control Room.

Each Gas turbine controller will have independent SOE monitoring function4.4 13.8 kV Generator Switchgear ( GLAC )13.8 kV Generator Breaker control & protections shall be as per GE Standard. 13.8 kV Generator breaker control will be through Local HMI & remote HMI to be provided in the existing control room.

4.5 SOER System & Master clock

Time synchronisation of GTG's and Electrical SOER system shall be carried out by a Master clock.

4.6 Fuel oil system

4.6.1 Fuel oil Unloading Unit :

Unloading pumps will be started / stopped individually from local push button station. No remote operation is envisaged for unloading pumps as the unloading pumps need to be operated locally in the presence of operator to ensure hose connections are made properly. Start /Stop indications and pump trip alarm will be provided on remote control panel in the existing control room..4.6.2 DFO Storage tanks :

Level transmitters will be provided on DFO tanks. Tank level low, low low, high, high high will be derived from level transmitter signals and will be displayed on remote control panel to be located in the central control room. Based on the levels in the tank, operator will chose to open / close the respective valve on the fill line of the tanks.

Low low level of the tank will be interlocked to fuel forwarding skid for protection of the forwarding pumps.4.6.3 Fuel Forwarding SystemEach GTG unit is provided with two fuel forwarding pumps ( in 2x100% configuration) to pump the fuel oil from the storage tanks to the GTG units at the requisite pressure. Automatic recirculation arrangements are provided in the discharge lines of the forwarding pumps, so as to maintain the fuel oil pressure at the required level (at the inlet to the GTG units).

The stand-by pump will come into operation automatically (through suitably provided system interlocks) if the working pump trips or malfunctions or the oil pressure in the common discharge line falls below a pre-set level.

Start, Stop and Operation of the forwarding pumps will be implemented locally by a panel and remotely through the GT control systems.

The control system will be based on the manufacturers proven product line.

Start /Stop indications and pump trip alarm will be provided on remote panel in the existing control room. In addition, the system will also have sufficient provisions for integration with the future DCIS (for pump trip alarms).

4.7 HVAC System

4.7.1 Ventilation System

The following areas will be provided with ventilation system :

1) Power house: Each unit will have a local control panel to Start/Stop the ventilation system, another Start/Stop control and common alarm will be configured in the unit Mark VI Controller and will be shown at respective HMI. 2) Battery room

3) Toilet.Start and stop of the ventilation system fans for the above two areas will be through wall mounted local push button stations.

4.7.2 Air Conditioning System

2x100% capacity packaged air cooled DX units are provided for main switchgear room. The Air Conditioning system will be designed and installed to provide automatic temperature controls (ATC).Safety and limit automatic controls such as freeze starts, firestats, flow switches, smoke detectors, refrigeration low-high pressure controls etc. will be provided for safe operation of the Air Conditioning system as per applicable standards.

The control system will be provided with electric/electronic/pneumatic and self contained controls as applicable. All thermostats will be manually adjustable over the entire operating range.

The performance of AC system will be controlled by a thermostat located in the supply air stream at coil discharge or in the return air stream within the conditioned space (based on the manufacturers practice)

The controls for heating will be interconnected with air conditioning system with a minimum of 3.3(C (6(F) dead band between heating cut-off and cooling start temperatures for all applications where more precise temperature control is not required.

A common alarm for the AC system will be generated in the Central Control Room.

4.8 Fire fighting and Fire Detection /Alarm System :

The fire fighting system for Arar generation expansion is essentially an extension of the existing fire fighting system. The fire fighting system will be operated through locally provided fire control panels.

Adequately designed Fire-water, CO2 and foam sprinkler devices are provided throughout the extension unit, in line with Fire protection and Fire detection system design basis reports. Necessary provisions will be made for automatic operation of the Fire-water, CO2 and Sprinkler systems.

The two GTG units will be protected by in-built Fire Detection, Alarm and Protection system provided by the GTG supplier (GE). The controls for such devices will be dedicated type and will be as per GE standards and will be part of GE Control System.The plant fire fighting system comprises of local panels at each building and main control panel at existing control room.

The main control panel will receive status/alarm signals from Foam/Fire water spray/CO2 systems from respective local panels. The local panels will generate fire alarms in case of fire in that area. Detectors provided in the various area will initiate Alarms and release of Water/Foam/CO2 as the case may be.

The manual fire alarm stations provided at different locations will initiate audio/visual alarms in the local and Main Control Panel.

4.9 Compressed Air System

The compressed air system will be used for the service and instrument air requirements of the proposed plant along with inlet filter air cleaning requirement of the GTG units during the shut-down conditions. It may be noted here that the compressed air required for equipment falling under GE scope of supply and for inlet air filter cleaning during normal plant operation will be provided by respective GTG unit extraction.

Three numbers of air compressors are provided for the expansion plant, in 3x50% configuration. Out of these three compressors, two will be operating on load/unload control, and one (1) compressor will be operating on auto start/stop control. There will be a selector switch for each compressor having three positions to select in Auto-Manual-Off mode of operation. Each compressor will also be provided with selector switches to select load/unload or Auto start/ stop duty. After selecting the load/unload or Auto start/stop duty for each compressor and Auto mode in Auto-Manual-Off switch, the base duty compressors will be started. The compressor selected for Auto start/stop duty will start and stop automatically based on pressure switch settings. There will be individual pushbuttons for each compressor to start-stop in manual mode of operation. Out of the two operating compressors, when one compressor fails or is under maintenance, the common stand-by compressor will be started automatically and will be on load/unload regulation meeting the total compressed air requirements of the plant.

In cases when the compressed air requirements of the plant can be met with just one compressor in running condition, the remaining two compressors can be put under auto start/stop mode.

A common alarm of the compressed air system will be generated in the Central Control room.

4.10. Common Drainage system.

Gas Turbine false start and oil drain pit HI and Low alarms will be connected to HMI and accordingly Pumps will start and stop by interference of the operator (this system should be operated manually for safety reasons).Gas Turbine water wash drain tank HI-level alarm signals to be connected to central control room.Oily water drain tank near fuel tanks and Transformer oil water collection tank alarm signals (Low & HIGH) to be connected to Central Control Room. ( the pumps will have selection of Auto/Manual)5.0CONTROL PHILOSOPHY FOR ELECTRICAL EQUIPMENT

5.14.16kV Station Switchgear:

The 4.16kV Station Switchgear would be located in New Switchgear building. All protections along with Digital Power demand meter (DPDM) would be mounted as part of the Switchgear.

Local/Remote selector switch for breaker shall be provided on breaker panels.

Local control of 4.16kV Breakers is envisaged only for testing purposes. Control of circuit breakers in service position would be from Remote Control panel only.

Remote Control panel for 4.16kV Station Switchgear would be provided as per clarification No. 04 Q 31 & A31 dt. Dec 10th 2003. The same would be located in the existing control building. This panel would be provided with indication for breaker, mimic with breaker control switches & selector switch for manual synchronisation of incomer & bus coupler breakers. Control of all incomer feeders, bus coupler & outgoing feeder circuit breakers would be provided on this panel.

Auto Transfer Scheme (ATS) to achieve Auto transfer of auxiliaries would be provided in the switchgear and selector switch for the same shall be provided on the Remote Control panel of 4.16kV Station Switchgear for incomers & bus coupler.

5.2480V Station Switchgear:

The 480V Station Switchgear would be located in New Switchgear building. All protections along with Digital Power demand meter (DPDM) would be mounted as part of the Switchgear.Local control of 480V incomer and bus coupler Breakers is envisaged only for testing purposes. Local/Remote selector switches for these breakers shall be provided on breaker panels. Control of incomer & bus coupler circuit breakers in service position would be from Remote Control panel only. For all outgoing circuit breakers, only local control from switchgear would be provided.Remote Control panel for 480V Station Switchgear would be located per clarification No. 04 Q 31 & A31 dt. Dec 10th 2003. The same would be in the existing control building. This panel would be provided with mimic with breaker control switches.

Auto Transfer Scheme (ATS) to achieve Auto transfer of auxiliaries would be provided in the switchgear and selector switch for the same shall be provided on the Remote Control panel of 480V Station Switchgear for incomers & bus coupler.

5.3480V Unit Switchgear:

The 480V Unit Switchgear would be located in Unit Switchgear room.

Local control of 480V Incomer Breakers is envisaged only for testing purposes. Local/Remote selector switches for these breakers shall be provided on breaker panels. Control of incomer circuit breakers in service position would be from Remote Control panel only. For all outgoing circuit breakers, only local control from switchgear would be provided.

Remote Control panel for 480V Unit Switchgear would be located per clarification No. 04 Q 31 & A31 dt. Dec 10th 2003. The same would be in the existing control building. This panel would be provided with mimic with breaker control switches and selector switch for manual synchronisation of incomer feeders Auto Transfer Scheme (ATS) to achieve Auto transfer of auxiliaries would be provided in the switchgear and selector switch for the same shall be provided on the Remote Control panel of 480V Unit Switchgear for incomers.

5.4480V MCCs / Distribution Boards:

Only local control of incoming and outgoing feeders would be provided for all other 480V Distribution boards / MCCs.

5.513.8kV/132kV Generator Transformers:

Relay panel for Generator Transformer would be located in existing Control building. Separate Relay panels would be provided for Set-1 & Set-2 protections as per Cl.No 1.1 of Appendix-V of PTS-1022.

Remote Tap Changer Control Panels for Generator Transformers would be located in existing control room as per Clause No. 6.15.03 of PTS 1022.

5.633/4.16kV Station Transformers:

Relay panel for Station Transformer would be located in existing Control building. One Relay panel with segregation between Set-1 & Set-2 protections would be provided for each Station Transformer as per Cl.No 6.7 of Appendix-V of PTS-1022. The relay panel would be located in existing control room.

5.74.16/0.480kV Station Auxiliary Transformers:

Protections for Station Auxiliary Transformers would be located in respective Switchgears (HV side protections in 4.16kV Switchgear & LV side protections in 480V Station Switchgear).

Remote Tap Changer Control Panels for Station Auxiliary Transformers would be located in existing control room as per Clause No. 6.15.04 of PTS 1022.

5.813.8kV/0.480kV Unit Auxiliary Transformers:

Both HV and LV side protections for Unit Auxiliary Transformers would be located in 480 V Unit Switchgears.

5.9SOER SYSTEM :

SOER Panel for Generator, Generator Transformer and Auxiliary Transformers would be provided in existing Control Room and would be interfaced with new operator console (remote HMI) in existing control room as per CL.No1.0 of Appendix-VI of PTS-1022. Below, are the main items to be provided for the SOER:

a. SOE RTU/IFC PANEL WITH512 SOE POINTSb. gps receiverc. MMI PANEL EQUIPPED WITH1. mmi pc hardware & software2. mmi graphic display built3. printer4. iec-870-5-104 interface5. 8 port hub

6. redundant power supply (inverter)5.10Annunciation System:

A common Annunciation panel for new 4.16KV and 480V system will be provided in existing control room.

EMBED Word.Picture.8

P0B

11-01-2005MPSR

P0A

18-11-2004MPSR

REV NO . DATEPREPARED BYCHECKED BYCLEARED BYAPPROVED BY

FILENAME : modif Control Philosophy of Arar- 13-2-05

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