多相无刷励磁系统旋转整流器故障的仿真与识别

多相无刷励磁系统中旋转整流器的损坏时有发生,故障恶化将严重影响主发电机的正常安全运行。为识别旋转整流器的故障,建立了包括旋转整流器在内的整个多相无刷励磁系统的多回路数学模型,对旋转整流器的正常运行和常见故障状态进行了仿真,仿真结果同励磁机额定运行值以及实验结果吻合。分析了旋转整流器各种状态时励磁机稳态定子励磁电流的频谱,并对特征机理进行了理论分析,在此基础上提出以励磁机定子励磁电流的4次谐波分量同22次谐波分量的比值作为故障识别对象,为多相无刷励磁系统旋转整流器故障诊断提供了理论依据。

Simulation and Recognition for Rotary Rectifier Fault of Multi-Phase Brushless Excitation System

Damage of rotary rectifier in multi-phase brushless excitation system occurs frequently,which would seriously affect the normal safe operation of the main generator in deteriorating condition.In order to study fault recognition of the rotary rectifier,the multi-loop model of multi-phase brushless excitation system including the rectifier is established.The normal state and the common fault states of the rectifier are simulated,and the comparison between the calculated results and the experiments verify the validity of the model and simulation.The components with different frequencies of stator currents under different states of rotary rectifier as well as their mechanism are analyzed theoretically,based on which the ratio of the 4th to the 22nd harmonic component of the stator current is suggested to be the fault recognition object,which provides a theoretical basis for fault diagnosis of rotary rectifier in multi-phase brushless excitation system.