摘要
传统同步调相机定子绕组匝间短路故障机理分析方法通常认为电机定子电流接近三相对称,并以此为基础建立同步调相机故障电流的数学表征。但是,一旦发生定子绕组匝间短路故障,同步调相机三相定子电流的对称性将遭到破坏,使得传统故障机理分析方法所建立的数学表征无法准确反映电机内部电气量的变化。文中通过引入对称分量法,建立故障后同步调相机瞬时有功/无功功率的数学模型,提出利用瞬时有功/无功功率中的2次谐波进行定子绕组匝间短路故障诊断。仿真和实验的结果表明:相较于利用定子电流3次谐波与基波幅值之比诊断故障的传统方法,文中方法在轻微故障状态下能提高至少7倍的诊断灵敏度,更易完成早期故障诊断。同时,所提方法中的故障特征量不受同步调相机工况和故障位置的影响,具有强鲁棒性。
The traditional method for analyzing the mechanism of stator winding inter turn short-circuit faults of synchronous condensers usually assumes that the stator current of the motor is close to three-phase symmetry,and based on this,a mathematical representation of the fault current of synchronous condensers is established.However,once a stator winding inter turn short-circuit fault occurs,the symmetry of the three-phase stator current of the synchronous condenser will be disrupted,making the mathematical representation established by traditional fault mechanism analysis methods unable to accurately reflect the changes in the internal electrical quantities of the motor.A mathematical model is established for the instantaneous active and reactive power of a synchronous condenser after a fault by introducing the symmetrical component method.Using the second harmonic in the instantaneous active and reactive power for stator winding inter turn short-circuit fault diagnosis is proposed.The simulation and experimental results indicate that compared to the traditional method of diagnosing faults using the ratio of the third harmonic of stator current to the amplitude of the fundamental wave,the proposed method can improve the diagnostic sensitivity by at least seven times under mild fault conditions,making it easy to complete early fault diagnosis.At the same time,the fault feature quantities in the proposed method are not affected by the synchronous condenser operating conditions and fault locations,and also have strong robustness.
作者
谷兵
蒋琛
黄思遥
蔚超
王伟
程明
GU Bing;JIANG Chen;HUANG Siyao;WEI Chao;WANG Wei;CHENG Ming(Jiangsu Frontier Electric Technology Co.,Ltd.,Nanjing 211102,China;School of Electrical Engineering,Southeast University,Nanjing 210096,China)
出处
《电力工程技术》
北大核心
2024年第2期210-217,共8页
Electric Power Engineering Technology
基金
国家自然科学基金资助项目(51991384)。
关键词
同步调相机
定子绕组匝间短路
对称分量法
瞬时功率
故障诊断
特高压直流输电系统
synchronous condenser
stator winding inter turn short-circuit
symmetrical component method
instantaneous power
fault diagnosis
ultra-high voltage direct current transmission system
