Vibration Analysis and Fault Diagnosis of Generator Units

Aims at the key technical problems in the safe and stable operation of large scale power generation units, study is carried out in three areas including the design, maintenance and control of units. Application foundation and engineering research are carried out concerning rotating machinery rotor dynamics, vibration analysis, fluid-structure interaction analysis, fault diagnosis and treatment, condition monitoring and surveillance, optimization of structure dynamic characteristics design, which satisfies the continuing developing electric industry and improves the security and reliability of large scaled power plant units in our country.

Our institution has already obtained some important research achievements. Such as:

●Abnormal vibration diagnosis and treatment technology of large-scaled generator units

Shaft load distribution testing, analysis, optimization, adjustment technology was proposed to solve the technical problems that have long puzzled power plants. And to improve the efficiency of balancing and fault diagnosis accuracy, balancing technology and vibration fault diagnosis technology were developed. With this method, the first-time success balancing rates above 75%, fault diagnosis accuracy rates above 90%. Severe and puzzling problems in more than one hundred units in more than forty power plants were successfully solved, including nuclear power plants in Tianwan, Taishan and coal-fired power plants in Pingwei, Xuancheng, Yaomeng, Fuzhou, Qinghe and Jinjiang. During the past five years, 1.45 billion yuan direct economic benefits have been created. And this achievement won the First Prize of Science and Technology Progress Award of Jiangsu Province and the Third Prize of National Science and Technology Progress Award.

●Vibration testing, analysis, monitoring technique and system of large-scaled generator units

Southeast University is the earliest to study and develop the vibration analysis instrument. During the recent 30 years, following products have been worked out: the SE series vibration sensors (displacement, velocity and acceleration), the ZXP series single-forty channel vibration analyzer, the vibration monitoring, protection and accident remembrance device TSI, the unit vibration on-line analysis system TDM and the vibration calibration system. Such instruments have been widely used in the rotating machinery in power, petrochemical, metallurgy industry. The annual sale is more than 2000 sets and the instruments have partially replaced similar foreign products.

●Condition monitoring, fault analysis and performance optimization technique and system under  SIS platform

Condition monitoring, fault analysis and performance optimization system under SIS platform was developed to save energy and reduce emission. The system consists of online monitoring and integrated platform, unit performance computing and optimization platform, online monitoring and fault diagnosis platform. With the online monitoring of parameters of the whole plant, surveillance, analysis, diagnosis and management of units is realized. Such system helps to know the condition of units, prevent fault, and improve operating and maintenance, ensure the safe and economic operating of units. The study result has been applied in several power plants.

Currently the focuses of research are as including follows:

(1) Rotor dynamics and vibration analysis techniques of rotating machinery in coal-fired, nuclear, wind, hydro power plants;

(2) Advanced sealing technology;

(3) Flow-induced vibration suppression technology;

(4) Signal analysis and condition monitoring techniques;

(5) Development of various sensors and vibration testing, analysis, monitoring instruments.