Research On Key Technologies Of Electromagnetic And Structural Design Of 60Hz Air-cooled Turbogenerator

At present,the domestic economic situation is slowing down,the conventional coal-fired power plant is overcapacity,and the domestic 50 Hz turbo generator product demand is shrinking.In order to make full use of the existing production capacity of the manufacturing plant and make up the market gap caused by the decline of the 50 Hz turbo generator demand,we need to develop new products and open up the international market.Especially with the promotion of national "The Belt and Road" strategy,our country will be along with emerging economies and developing countries to establish more extensive cooperation relationship.Developing 60 Hz Air-cooled turbo generator that meets the needs of the international market is of great significance for the national strategy to digest and manufacture capacity.For the design technology of 60 Hz generator,Harbin Electric has introduced Westinghouse 600 MW turbo generator technology.In recent years,Harbin Electric has introduced the 390 H type generator of the GE Company of the United States.But it is undeniable that the domestic research and development of 60 Hz Air-cooled turbo generator is still lack of systematic research.It is very necessary to carry out research on the key technologies of 60 Hz air cooled turbo generator’s electromagnetic and structural design.This paper compares the electromagnetic design of 50 Hz and 60 Hz Air-cooled turbo generator,summarizes the characteristics of 60 Hz air cooled turbo generator in electromagnetic design.Based on the 150 MW export project,research the main indexes of efficiency,temperature rise,magnetic density and negative sequence capability,and studies the overall structure of 60 Hz Air-cooled turbo generator and the structural characteristics of all key components.Verify product reliability by type test according to the electromagnetic parameter design and structural design of the product.The causes of negative sequence current of turbo generator are summarized,and the influence and harm of negative sequence current on the generator are studied.The negative sequence capacity of the rotor is calculated by the finite element method.According to the standard that the negative sequence capability of continuous operation is more than 10% and the negative sequence capability of fault operation is more than 10 s,the highest temperature of the material of rotor structure in long-term and short-term operation meets the requirements of the standard.The finite element method is used to calculate the stress and deformation of the stator frame under various working conditions.The vibration mechanism of stator core and stator frame is introduced.The vibration of stator core,stator frame vibration and stator isolation system are analyzed comprehensively using analytical method and finite element method.According to the analysis of the negative sequence capability and vibration the generator can operate safely,reliably and continuously under rated and other special conditions.