7HA Users

Challenge. Soon after commissioning, one of Fairview’s gas turbine/generators experienced stator-ground-fault trips attributed to isophase-bus (IPB) water ingression into potential transformer (PT) cabinets, followed by persistent lower-than-expected resistance readings. Doble Engineering was engaged to perform electromagnetic interference (EMI) testing on several components of the plant’s three power trains to assess their condition. Generators, step-up transformers …

Best Practice: Use EMI to assess the condition of generators, transformers, HV electrical gear Read More »

The state-of-the-art gas turbines (GTs), such as the H-class and J-class machines, are designed to maximize fuel-to-electricity efficiency, achieving and even exceeding 60% in combined-cycle mode. Already, there are an impressive number of these machines in the field; one supplier listed 80+ H-class GTs operating, in commissioning, being installed, or on order. This achievement is …

Latest GTs pose special challenges for NOx, CO catalyst system design Read More »

Two of the biggest, bad-ass gas turbines currently operating in the US are proceeding through their paces at Exelon Generation’s 2 × 1 Wolf Hollow II facility, Granbury, Tex, southwest of Fort Worth. CCJ editors stopped in to visit with Plant Manager Jeff Klier during a recent swing through the state. Of utmost importance to …

Wolf Hollow offers early glimpse into H-machine performance Read More »

A CCJ ONsite Special Report Welcome the 7HA Users Group into the pantheon of power-industry organizations seeking peer-to-peer interaction to solve problems expeditiously and provide a collective check on official OEM positions regarding fleet- and plant-level issues. Representatives from well over a dozen facilities and five countries, responsible for 30+ machines, attended the inaugural 7HA …

7HA users wrestle with emergent issues at inaugural meeting Read More »

The Power Cycle Chemistry (PCC) working group of the International Association for the Properties of Water and Steam participated in the 2019 IAPWS annual meeting in Banff, AB, Canada, Sept 29 – Oct 4, where it announced the availability of several new Technical Guidance Documents (TGDs) and provided updates on the development of others. The …

New IAPWS documents provide guidance on generator cooling water chemistry, film-forming substances, air in-leakage Read More »

Plant digital systems are not necessarily top of mind when acquisitions are undertaken, reminds Tyler Ward, VP security of Infinite Group Inc (IGI), Rochester, NY. That includes cybersecurity. Organizations are not only inheriting equipment, employees, finances, and practices of the other party—but also the cybersecurity practices (good or bad) and accompanying potential cyber risks. Yet very few …

Make sure cybersecurity issues don’t overwhelm an acquisition Read More »

During the 7HA Users Group Conference second day, “GE Day,” high-level managers kicked off the event by proclaiming “significant progress in [corporate] restructuring,” HA technology investment is up in 2019, and “we are moving from financial metrics to operating metrics, and users should feel this going forward.” GE officials shared progress on several issues discussed …

GE Day @ 7HAUG: Some permanent solutions in place, other root-cause analyses on-going Read More »

Now in its second year, the 7HA Users Group Conference fosters an open and transparent dialogue among users and the OEM on all aspects of the turbine, so that technical issues can be resolved and best practices shared. Because the 7HA fleet is relatively young, the user group’s steering committee has structured the event to …

7HAUG 2019: Progress with centerline issues; non-drive-train topics dominate discussion Read More »