Applying a Braking Resistor Bank to Restrict Impacts into Turbine Blades

• Main Authors: Chen-Chi Chou, 周陳吉
• Other Authors: T.P.Tsao
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/34721001416647779604

碩士 === 國立中山大學 === 電機工程學系 === 87 === A good approach to suppress turbine blade vibration arising from power system faults is examined in this thesis. The research is to restrict the initial vibration amplitude so that the impacts into turbine blades can be alleviated. The proposed method is different from the other techniques used in the past. The technical feasibility of using a dynamic braking resistor (BR) to damp the torque vibration in turbine blades is proposed in the thesis. At power system faults, subtransient and transient peak currents occur in power system. The peak electromagnetic torque would also arise to impact into the turbine-generator. The largest fault energy can be dissipated to damp the turbine-generator vibrations due to the braking resistor switching into the power system at the first few cycles of faults. In this thesis, 951MW unclear power generation unit has been simulated under the multi-phases system faults. To illustrate the effect of the braking resistor to the turbine blade vibration phenomenon, there are two types of severe faults to be simulated here, and shown the effect of different clearing time and rated capacity of resistor. Because the braking resistor is activated only at the instant of a disturbance and lasts very short time, it consumes very small amount of energy. It is found from the results of simulation analysis that only one cycle of turn-on time is adequate to restrict impacts into turbine blades.