基于定子振动特性的汽轮发电机气隙偏心故障程度鉴定方法研究

Eccentric fault level identification of a turbo-generator based on stator vibration characteristics

提出一种应用汽轮发电机定子通频振动烈度与特定频率成分振动幅值比对来鉴定气隙偏心故障程度的方法。对发电机定转子振动影响因素进行对比分析,得出定子振动主要受气隙偏心等因素影响导致气隙磁密故障,论证所提方法的可行性;分析推导偏心故障前后电机定子的振动特性变化,给出偏心故障程度具体鉴定计算方法;在SDF-9故障模拟发电机上进行实验验证。结果表明,该方法能在整体上较为客观地鉴定出发电机偏心故障程度,具有参考价值和积极意义。

An eccentric fault level identification method of a turbo-generator based on comparing stator vibration pass-band intensity and some specific frequency component＇s amplitude was presented here. The factors affecting vibration of the stator and the rotor were firstly analyzed and compared to demonstrate the feasibility of the proposed method. It was shown that the stator vibration is mostly affected by those faults influencing magnetic flux density, such as, air gap eccentricity. Then, the stator vibration characteristics under the normal condition and the eccentric faults were analyzed and compared, and a specific identification method was proposed. Finally, a test verification was performed on a SDF-9 fault simulating generator. It was shown that the eccentric fault level can be objectively identified with the presented method. The results provided a new thought and a reference for fault level recognition of a turbo-generator.