The document discusses excitation systems for power plants and their importance. Excitation systems provide variable DC current to control terminal voltage, reactive power, and power factor. They ensure stable operation with the network and other machines. Outdated excitation systems can result in inefficient plant operation, shutdowns, and network instability. Upgrading to a modern, efficient excitation system provides benefits like higher availability, reduced maintenance costs, less outage time, better power system stability, and longer-term spare parts and support availability. The presentation provides a case study and recommends existing plants audit their excitation systems and consider upgrades.

1. Excitation System for an efficient and stable Power Plant and Network. Presenter: Aqeel Ahmed

2. Presenter Profile Aqeel Ahmed (Dy. General Manager Head of ABB Pakistan Southern region) Academics Working Experience Achievements

3. Contents Excitation System and its place in a Power Plant Functionality of Excitation System Issues with Outdated Excitation Systems Technology & functionality benchmark Summary - Benefits of efficient Excitation System Why Upgrade? A case Study Conclusion and Actions

4. Inefficient excitation System results in Inefficient Power Plant operation Shutdown of Excitation System / AVR = Power Plant Shutdown

5. Power Station SYNCHRONOUS GENERATOR TURBINE GOVERNOR EXCITATION TRANSFORMER 2 EXCITATIONSYSTEM GENERATOR BREAKER 1 1 SYNCHRONIZING 2 PROTECTION STATIC STARTER CONTROL SYSTEMS AC & DC AUXILIARY SYSTEMS STEP UP TRANSFORMER HV- BREAKER HV SYSTEM CONTROL ROOM PT’s & CT’s AUX. TRANSF. STAR POINT CUBICLE LV SWITCHGEAR

6. Functionality: Excitation systems Providing variable DC current with short time overload capability Controlling terminal voltage , MVAR and PF with suitable accuracy Ensure stable operation with network and / or other machines Contribution to transient stability subsequent to a fault. Communicate with the power plant control system Keep machine within allowed operating range Excitation systems/ A utomatic V oltage R egulators (AVRs) for Power Plants are managing: AVR Excitation Transformer Converter AC CB PT CT Controller Field Discharge

7. Technology & functionality benchmark Smart redundant power converter solutions for all regulation, monitoring, protection and control functions Power System Stabilizer (PSS) Powerful Real Time Power Plant Simulator Excitation Control Terminal (ECT), Communication with all leading Power plant control systems Customer Benefits Prolonged maintenance-free operation Easy to monitor and operate Easy plant integration

8. Redundant and Specially designed Powerful Converters Various redundancy concepts for control and power electronics Power converter modules up to 4150 A and up to 6 modules in parallel Insulation level to withstand stresses imposed to the field winding Dynamic current sharing among parallel bridges Maintenance in operation Customer Benefits Less outage time  High availability  Less production losses due to Power Converter failures => Higher profit Less maintenance

9. Vast Power System Stabilizer solutions Standard IEEE 2A/2B and Multiband PSS (IEEE 4B) covering most applications Adaptive PSS for changing network topology Integrated and stand-alone execution System study and modeling capabilities Customer Benefits Wide range of solutions to improve network stability Pre-calculation of PSS tuning PSS update of existing plants

10. Powerful Real Time Power Plant Simulator Factory testing with a Power Plant Simulator Parameter optimizing prior to commissioning AVR testing during machine overhaul Customer Benefits Less site tests and shorter commissioning time Reduced no-load testing time and fuel costs Easy training of plant staff

11. Excitation Control Terminal (ECT) Local and/or remote control terminal Stand-alone industrial PC with color touch screen Modbus TCP communication Password protected access levels Selectable languages Customer Benefits Comprehensive data acquisition and representation Independent data storage Simple and fast troubleshooting

12. REDUCED OPERATION COSTS - Less maintenance time - Less outage time due to less component failures and efficient redundancies - Less spare parts cost - Reduced no load testing time and fuel costs HIGHER AVAILABILITY - P lant availability due to efficient redundancy & conservative margins - Support is always available BETTER CONTRIBUTION TO POWER SYSTEM STABILITY - Faster response time - Better stabilization of power oscillations Summary - Benefits of efficient Excitation System

13. SPARE PARTS - spare parts are not available anymore - spare parts are very expensive MAINTENANCE - the system needs often maintenance work - maintenance lasts for several days PERFORMANCE/RELIABILITY - the network is unstable - the system causes high no. of faults - insufficient support from the system manufacturer Issues with Out dated Excitation systems

14. Why upgrade? A case study

15. Conclusion and Actions Upcoming Power Plants Investors need to ask the Power Plant supplier, which Excitation System is offered in the EPC package and the local support of the system. Existing Power Plants Get audit support from quality manufacturers about the performance of the excitation system and comparison with the new systems