It is very important to monitor vibration and diagnose fault for the operating safety of turbine-generator. The remote monitor and diagnosis via the cyber-based technology is a necessity. The difference between browser/server mode and client/server mode is discussed. There are many advantages of applying Java technology. Using Java, a vibration monitoring and fault diagnosis system of turbine-generator based on browser/server mode is developed. The functions as well as the structure of the whole system are analyzed. Online transmission of batch data via Internet is presented, especially for different program languages. Java Applet technology is used to develop client program. With double-buffer method, a lot of graphic interfaces of dynamic making online are presented, which are not blinking. It is proved that the system is already adopted and functions well in several power plants.

Due to the disturbance of electric power system or other shock load, the torsional vibration of turbine-generator shafts occurs. It is significant to calculate the response of torsional vibration excited by the disturbance of electric power system in order to analyze and prevent catastrophic accident. The multi-mass lumped model of turbine-generator shafts is used. A new method of response calculation of torsional vibration of turbine-generator shafts, the Increment Transfer Matrix method (ITM), which combines the Riccati transfer matrix method with the Newmark-β step-by-step integral method, is presented. By the ITM method, the transient response of torsional vibration of turbine-generator shafts, especially at the dangerous cross-sections, can be calculated. The responses of torsional vibration of 200MW turbine-generator shafts due to the generator at non-all-phase operation are calculated and analyzed. The cause of bolt broken of the coupling of intermediate-pressure rotor and low-pressure rotor and the coupling of generator and exciter are discussed. The results are identical with the data recorded in field.