采用重复脉冲法诊断发电机转子绕组匝间短路故障

Inter-turn Short Faults Dignosis on Rotor Windings of Generator Using Repetive Surge Oscilloscope

重复脉冲法(repetitive surge oscilloscope,RSO)是用于诊断发电机转子绕组匝间短路的试验技术。为此,介绍了重复脉冲法的基本原理,讨论了脉冲信号在电机转子绕组内的传播过程。依据传播特性,建立了反映该传播过程的分布参数电路模型并采用时域有限差分法求解得出绕组内部的暂态波形曲线,分析了该算法的稳定性。然后基于该模型讨论了注入信号的上升沿时间和转子绕组的故障特征对匝间短路故障诊断精度的影响。研究结果表明:重复脉冲法适于对转子绕组进行跟踪分析,其诊断结果的影响因素主要包括匝间短路故障位置和注入信号的上升沿时间,可通过缩短注入信号的上升沿时间来提高诊断精度。

RSO（repetitive surge oscilloscope）is a technique which is applied in the detection of inter-turn shorts in generator rotors.We introduce the basic principle of RSO,and discuss the propagation of the pulse signal in the rotor windings.According to the property of the propagation,a distribution parameter circuit model which can reflect the propagation of the signal is established,the finite difference time domain（FDTD）method is used to obtain the waveform of the rotor windings,and the stability of the algorithm is analyzed.Moreover,influences of rising time of the injected signal are discussed,and the influences of fault signature in rotor windings are also discussed.The conclusion can be drawn as follows：RSO is suitable for follow-up analysis,the influential factors of the diagnosis include the location of the inter-turn shorts and the rising time of injected signal.The diagnostic accuracy can be improved by shortening the rising time.