Aswan high dam - Distributed control system AUTOMATION

Aswan high dam - Distributed control system AUTOMATION

Power System Overview Aswan High Dam (AHD) -Hydro Power Plant was erected and commissioned in 1972. At the time it was the world's greatest, as well as it's 450 km long, artificial, Nasser lake. The powerplant and the dam contribute overall Egypt's development in many ways. Most important are: maintaining constant level of the Nile river (floods protection, agricultural needs ), and stabile power supply during all seasons. Most outstanding AHD power plant's features are it's size and fast synchronization response. It takes 1 minute from standstill till synchronization and additional minute to reach the full load. Owing to these qualities, AHD power plant is appointed the leading role in the region's power generation and distribution system covering Egypt, Libya, Syria, Jordan, and Lebanon. It's task is to maintain grid's stabile frequency (50 Hz) and required voltage level (480-525 kv).

Power System Overview At full power, AHD power plant generates 2100 MW. It consists of 12 units, divided in 4 blocks. That enables simultaneous connection of 3 units to the grid. Each unit comprises: turbine (Frances type, max. gross head 74m), generator (60 pole, 100rpm, 180 MW max, 15.75 kv) unit transformer (500kV). There are 2 switchyards: 500 kv (2 exit lines) 132kV (4 exit lines and 2 feeders) There are 2 auto-transformers reducing the voltage from 500 kv to 132 kv and 6 kv. Internal power supply is additionally secured with 2 station service transformers attached to units 1 and 7.

Controls upgrade project Upgrade Project Controls upgrade project was started in 2000. Main reasons for implementation of a new distributed control system were: 1) expensive and difficult maintenance of old, relay logic based control system 2) need to improve overall performance and efficiency of AHD hydro power plant: control, post-trip analyzing, trend recording, protection, etc. Scope Control system (DCS) Central control room, mimic board and electrical room Automatic and manual synchronization device Transducers, transmitters and instruments Information management system (IMS) Protection system Power and control cables and cable trays Air conditioning system

Controls upgrade project Outcome Since implementation of the project, reliability and operation safety are significantly increased. Units response time is improved. Supervision and control are simple and user-friendly. Power plant and control system maintenance routines are simpler. Life-time of primary equipment is increased. Post-trip analysis is efficient and accurate. All the improvements will further strengthen AHD power plant's leading position in Egypt and the region.

Automation and control system Equipment Power generation and distribution in AHD" is monitored and controlled by ABB Advant products family equipment: Process controllers - AdvantController 450 (17 units) Operator stations - AdvantStation 500 OS - (3 units) Operator stations - Windows NT based PC application (2 units) Information Management Station - PC based application - (2 units) Local Viewers - PC based application - (26 units) Control network MasterBus 300, Plant Network TCP/IP, MODBUS serial links etc. Event/alarm printers, hardcopy printers and report printers. Controller cabinet AC 450 Hardcopy AS 500OS AS 500IMS

Main ABB DCS equipment configuration Powerhouse Network Switch DCS room AC450 red. I/O Rack Screen Industrial PC Unit 1 AC450 M DI: 384 DO: 96 AI: 128 (4..20mA) AO: 16 PT100:155 IMS A AC450 T&M&G HA DBS IMS B AC450 T&M&G HA DBS AC450 DSV AC450 DSV... same for Units 2,...,12 CCR 500 kv Operator Station 1 AS530 OS 3 Operator Station 2 AS530 AC450 red. I/O Rack Remote I/O Racks Shift room Controllers room Workstation 1 Workstation 2 Network Switch AC450 red. I/O Rack Remote I/O Rack AC450 red. I/O Rack

Distributed Control System Requirements ABB AHD DCS acts as a single and integral system regardless of it s complexity and equipment distribution. DCS controls and supervises: 12 generators 12 unit transformers 2 reactors 2 autotransformers 360 breakers 10200 physical I/O signals 500 serial I/O signals. Main tasks of ABB DCS in AHD power plant are: Supervision & control of all major power system equipment from control room. Ensuring voltage and frequency stability. Ensuring coordination of generators, optimizing and fault finding tools (reports, trends, process overviews, event & alarm lists, system status, system list,...). Local viewers support (local PC based process monitoring and display)

Automation and control system Scope Entire power system is controlled by process controllers and runs fully automatic. Each part can be controlled and monitored from any operator station. Control includes: turbines, generators, breakers, transformers, subsystems etc. Features Control logic in AC450 related to each generating unit includes: start & stop sequence, unit's circuit breaker handling, active & reactive power control, temperature control, MODBUS communication with protection system (generator protection unit GPU2000R, transformer protection unit TPU2000R), energy calculation, light and annunciation system. Generating unit can be controlled from operator stations or control console in central control room and from LHMI or manual controls on unit control cubicle. Unit synchronization devices are: ABB synchrotact 5202 (automatic) and ABB synchrocheck 5100 (manual). New control system was adjusted with existing excitation (auxiliary generator & thyristor excitation) and turbine ( Woodward governor) systems that were not changed.

Automation and control system Features Supervision and handling of circuit breakers (synchronization) is possible from operator station process displays and mimic board (hard-wired backup) in control room. Actual positions of earthing switches and isolators are presented on process displays. Remote control from dispatching center in Cairo is supported. Automatic reports, post-trip analysis and 1 year data storage for process data from AC450 controllers. Other Features Other DCS features include: redundancy (processors and communication), MODBUS serial links, GPS time sinchronization, long term data storage, data logging and trend displays,...

Operator's screen example

Intea s contribution Scope - general controller's cabinets design, specification and manufacturing supervision power plant distributed control system design (process logic functional description, site survey ) process controllers application design (signals database, programs, type circuits, testing) operator stations application design and customizing (process displays, dialogs) factory acceptance test with client (demonstration of system capabilities, changes implementation) site acceptance test commissioning (wiring supervision, I/O check, synchronization, transducers adjusting and installation, control logic commissioning ) unit & switchyard circuit breakers synchronization start-up training (operation and maintenance personnel) DCS modifications, extensions and maintenance Scope - sections Intea was responsible for configuration and application software in all Process Controllers, Operator Stations and Information Management Controllers, except for LHMI communication support software. Duration and results January 2001 September 2001, 6 Intea s engineers worked in Alstom, Denver on project design, cubicle production supervision and FAT-s. October 2001 November 2003, 6 Intea s engineers worked on site (in shifts) until successful handover. INTEA s work was recognized, by ALSTOM project management and end-user HPGC, as outstanding and highly professional. Post start-up projects: 2005-2010., DCS HW and SW deliveries: extensions, modifications, site activities and commissioning due to scheduled overhauls and modernization of generating units by Voith-Siemens. Total of 17 orders for various Aswan DCS equipment and works awarded to INTEA since 2001, testify of the client's satisfaction.