中小型无刷励磁同步发电机组旋转整流桥二极管开路故障的在线检测方法  

On-line detection method for rotating rectifier bridge diode open-circuit fault of small and medium-sized brushless excitation synchronous generator set

作　　者：武玉才[1] 庞永林 侯旭辰 WU Yu-cai;PANG Yong-lin;HOU Xu-chen(School of Electrical and Electronic Engineering,North China Electric Power University,Baoding 071003,China;Electric Power Research Institute,State Grid East Inner Mongolia Electric Power Company Limited,Hohhot 010020,China)

机构地区：[1]华北电力大学电气与电子工程学院,河北保定071003 [2]国网内蒙古东部电力有限公司电力科学研究院,呼和浩特010020

出　　处：《电机与控制学报》2021年第5期42-51,共10页Electric Machines and Control

基　　金：河北省自然科学基金(E2020502064);中央高校基本科研业务费专项资金(2020MS094)。

摘　　要：针对中小型无刷励磁同步发电机组旋转整流桥二极管的单管开路故障问题,提出一种基于柔性线圈的诊断方法。以一台改造184B型6.8kW三相无刷励磁同步发电机组旋转整流桥的一个二极管发生开路故障为例,结合励磁机电枢绕组的空间布局及其感应电动势特点分析了旋转整流桥二极管的导通规律,根据二极管开路故障前后电枢磁场的变化特征,获取了电枢磁场增量磁势特征并确立了故障判据,提出在励磁机定子铁轭上包绕柔性线圈,通过柔性线圈感应电压的25Hz转频分量检测和识别二极管开路故障。二维有限元仿真和样机实验结果表明,利用柔性线圈感应电压的25Hz转频分量可以实现对旋转整流桥二极管开路故障的在线检测。Aiming at an open circuit diode fault in the rotating rectifier bridge of small and medium-sized brushless excitation synchronous generator sets,a diagnosis method based on flexible coils was proposed.An open circuit diode fault in the rotating rectifier bridge in a modified 184B type 6.8 kW three-phase brushless excitation synchronous generator set was chosen as an example,and the conduction law of the diode in the rotating rectifier bridge was analyzed based on the spatial layout of the exciter armature winding and its induced electromotive force characteristics.According to the variation characteristics of the armature magnetic field before and after the open circuit fault,the incremental magnetic potential characteristics of the armature magnetic field were obtained,and the fault criterion was established.Finally,it was proposed to wrap a flexible coil on the stator yoke of the exciter,and detect and identify the open circuit diode fault through the 25 Hz rotating frequency component of the induced voltage of the flexible coil.Two-dimensional finite element simulation and experiment results show that the 25 Hz rotating frequency component of the induced voltage of the flexible coil can be used for the on-line detection of an open circuit diode fault in rotating rectifier bridge.

关 键 词：中小型无刷励磁同步发电机组 旋转整流桥 二极管 开路故障 柔性线圈 在线检测 

分 类 号：TM307[电气工程—电机]