| China's electric power industry,the most important foundation of energy industry in the development of the national economy,has a great significance to foster the national economy and the social progress.Not only does it connect the major strategic issues related to the national economic security,but also has a close relationship between people's daily life and social stability.With the development of China's economy,our continuously growing demand for the electric power,stimulate the forward of power generation.As the core device of power plant that the source of power supply,generator operating well or awful directly affects the efficiency of the whole unit.As we all know,the more increasing motor capacity,the more heat from its loss.Hence,increasing the motor capacity is under the condition of improving cooling technology.At present,air cooling and hydrogen cooling are commonly used in the the various cooling methods for turbo-generators,whereas the latter is more in China.Combined with the construction of generators,the internal 's hydrogen desiccator normal operation is essential to generator's safe and stable running.This paper detailed introduced the working principle of generators,the type,operation principle and benefits and drawbacks of hydrogen desiccator as well as system optimum idea and programmable logic controller.Based on these theories,a case study of phrase II 300 MW generators' irregular operation in SanHe power plant has screened the reasons of high hydrogen dew point temperature.Followed by the conclusion that the fault work of hydrogen desiccator is the root cause,the present study made a detailed analysis of the hidden danger the hydrogen dryer may generate,such as insulation cracking for generators and stress corrosion of the rotor's retaining ring and hydrogen explosion for workers.The corresponding measures is proposed as following: design a control chamber,employ SIMATIC S7-CPU224 PLC and temperature analog input module,install water level(WL)monitoring equipment,optimize the running process.Aforementioned measures not only reduce the probability of the risk occurring,but also to some extent it achieved a safe and energy-saving effect,saving the operation cost of power plant and upgrading the reliability of generators.According to the findings before and after the project,the research project collected relevant data,chose a series representative indicator in terms of security,economic,energy-saving three aspects and made a standardization disposal of the raw data.In view of comparative analysis indicators forth and back,experts were invited to rate the factors so that the weight of each factor was determined.To make the weight valuation more scientific and rational,a combination of qualitative and quantitative Analytic Hierarchy Process(AHP)was adopted,which can reflect the importance of factors to the project better.On account of above premise,this study utilizes fuzzy comprehensive evaluation(FCE)to establish evaluation model for this project.In conclusion,the evaluation result was between well and better,in favor of better,which verifies the optimization was ideal and meaningful. |
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