This paper briefs the developmental course, manufacturing and applications, as well as future prospect of excitation systems of large size turbogenerators in China, emphatically expounds the advantages of seif-excitat...This paper briefs the developmental course, manufacturing and applications, as well as future prospect of excitation systems of large size turbogenerators in China, emphatically expounds the advantages of seif-excitation systems with potential source reetifiers and matters needing to be noted during dissemination and application of them.展开更多
Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the la...Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the largest hydrodynamic thrust bearings ever built （external diameter 5,200 mm, axial load equals approximately 3,600 t）. This paper is an attempt to propose a new thrust bearing design with the use of the state-of-the-art technologies and simulation techniques that demonstrate a reduction of friction power losses generated by the thrust bearing. This paper is divided into two parts. Within the first one, the original thrust bearing design which was implemented in the generators is described. Related calculation results based on a TEHD （thermo-elasto-hydrodynamic） calculation software used by Alstom will be presented. A comparison between measurement results gathered in the 1980s is given. In the second part, a potential solution of a more beneficial bearing design is described. The proposed thrust bearing design modification is an implementation of Alstom＇s PolypadTM coating. This modern polymer （PEEK） coating material has already been used by Alstom in projects around the world for many years. This coating allows pushing the operating parameters limits toward higher temperatures and lower oil film thicknesses far beyond the limits known for the conventional bearing materials.展开更多
The authors propose a new closed cycle oxy-fuel gas turbine power plant that utilizes a nuclear heat generator. A pressurized water reactor （PWR） is designed to supply saturated steam to an oxy-fuel gas turbine for ...The authors propose a new closed cycle oxy-fuel gas turbine power plant that utilizes a nuclear heat generator. A pressurized water reactor （PWR） is designed to supply saturated steam to an oxy-fuel gas turbine for a specific power output increase The saturated steam from the reactor can have lower pressure and temperature than those of an existing PWR. In this study, the authors estimated plant performances from a heat balance model based on a conceptual design of a hybrid plant and calculated the generating costs of the proposed plant from the Japanese cost data of an existing PWR plant and an liquefied natural gas （LNG） combined cycle gas turbine plant. The generating efficiency of an oxy-fuel gas turbine plant without a nuclear steam generator is estimated to be less than 35%. Based on this efficiency, with a nuclear steam generator contributing to the power output of the proposed hybrid plant, the corresponding generating efficiency is estimated to be around 45%, even if the steam conditions are lower than in an existing PWR. The generating costs are 15-20% lower than those calculated from the weighted heat performances of both an oxy-fuel gas turbine plant without a nuclear steam generator and an existing PWR plant.展开更多
文摘This paper briefs the developmental course, manufacturing and applications, as well as future prospect of excitation systems of large size turbogenerators in China, emphatically expounds the advantages of seif-excitation systems with potential source reetifiers and matters needing to be noted during dissemination and application of them.
文摘Hydro generators installed in Itaipu Binacional power plant with 824/737 MVA rated output power （50/60 Hz） belong to the largest ones in the world. Among many unique features, the generators are equipped with the largest hydrodynamic thrust bearings ever built （external diameter 5,200 mm, axial load equals approximately 3,600 t）. This paper is an attempt to propose a new thrust bearing design with the use of the state-of-the-art technologies and simulation techniques that demonstrate a reduction of friction power losses generated by the thrust bearing. This paper is divided into two parts. Within the first one, the original thrust bearing design which was implemented in the generators is described. Related calculation results based on a TEHD （thermo-elasto-hydrodynamic） calculation software used by Alstom will be presented. A comparison between measurement results gathered in the 1980s is given. In the second part, a potential solution of a more beneficial bearing design is described. The proposed thrust bearing design modification is an implementation of Alstom＇s PolypadTM coating. This modern polymer （PEEK） coating material has already been used by Alstom in projects around the world for many years. This coating allows pushing the operating parameters limits toward higher temperatures and lower oil film thicknesses far beyond the limits known for the conventional bearing materials.
文摘The authors propose a new closed cycle oxy-fuel gas turbine power plant that utilizes a nuclear heat generator. A pressurized water reactor （PWR） is designed to supply saturated steam to an oxy-fuel gas turbine for a specific power output increase The saturated steam from the reactor can have lower pressure and temperature than those of an existing PWR. In this study, the authors estimated plant performances from a heat balance model based on a conceptual design of a hybrid plant and calculated the generating costs of the proposed plant from the Japanese cost data of an existing PWR plant and an liquefied natural gas （LNG） combined cycle gas turbine plant. The generating efficiency of an oxy-fuel gas turbine plant without a nuclear steam generator is estimated to be less than 35%. Based on this efficiency, with a nuclear steam generator contributing to the power output of the proposed hybrid plant, the corresponding generating efficiency is estimated to be around 45%, even if the steam conditions are lower than in an existing PWR. The generating costs are 15-20% lower than those calculated from the weighted heat performances of both an oxy-fuel gas turbine plant without a nuclear steam generator and an existing PWR plant.
