Session: 17-05-01: Steam Turbine Generators & Auxiliaries

Paper Number: 173887

Electrical Power Generator Upgrade and Uprate 

The global demand and forecast for electric power are at unprecedented levels.  Older legacy thermal machines, many previously identified for decommissioning, have remained in service and are being included in forecast generation.   Simple cycle and combined cycle applications manufactured prior to and during the gas turbine bubble are approaching or have exceeded the generally accepted 30 year design life of those machines.  Hydro Power remains entrenched as an integral part of the global power generation mix despite environmental pressures which seem cancelled by the green renewable attributes of Hydro.  Hydro asset owners are focused on priorities to ensure reliability through planned and effectively executed upgrades or life extensions with renewed focus on achieving the greatest power output possible.   

The demand and necessity for electric power generator upgrades and uprates are clear.  However, the best or most reliable path to achieve these is not as clear.  The best path includes not just a focus on the generator but rather on the entire drive train, from a holistic perspective. Certainly, all generator components need to be evaluated and proven capable of supporting an uprated output. Given the cost, time, and effort to plan and execute an effective uprate, it is wise for owners to keenly consider and understand the value of the uprate is significantly diminished if the fuel (water, gas, oil, coal) is not available to support production at the uprated output level, or if the GSU transformer and other transmission and distribution components are not capable to carry the uprated output from the generator.   

This presentation will explore upgrades / uprates starting with a definition of each and contrasting how they differ and relate, along with the value of performing them.  The advantages of initially performing an upgrade / uprate study will be shared with specific focus on how it can benefit planning and then the effective execution of the upgrade / uprate project.  Essential information to support the upgrade / uprate study along with the potential need for onsite data collection will be shared.  Study requirements including the specific determination of line up component capabilities relative to the targeted MVA / MW output will be explored and their importance to the project objective discussed.  Critical component evaluation factors of Electrical, Mechanical, and Thermal factors will be shared including discussing how they relate to study reporting of deficiencies found and recommendations.  Considerations and options to overcome component deficiencies and perform study recommendations will be shared. The myth of generator output rating being determined solely from a heat run will be addressed through a shared explanation of the importance of heat runs and their value when properly instrumented and performed at appropriate times to support project objectives. Key upgrade / uprate execution elements will be identified, and brief case examples shared.  A summary of important upgrade / uprate factors will be offered prior to a period of questions and answers.

Presenting Author: William Moudy National Electric Coil

Presenting Author Biography: Howard is currently Managing Director at National Electric Coil (NEC). Howard’s career has progressed through several different companies and positions over the past 44 years, primarily focusing on large high voltage rotating electric machines with an emphasis on coil manufacturing.

Authors:

William Moudy National Electric Coil