兆瓦级变速发电机组引出线断裂故障无接触式检测研究

Study on non-contact detection of outline fault in MW variable speed generator

为了实现兆瓦级变速发电机组引出线断裂故障无接触式检测,提出基于并网逆变器频率异常检测的兆瓦级变速发电机组引出线断裂故障无接触式检测方法。分析兆瓦级变速发电机组引出线的电流响应分量和电压分量,结合频率耦合控制方法进行兆瓦级变速发电机组引出线的参数特征分析,构建逆变器与电网的解耦股控制模型,根据兆瓦级变速发电机组的输入、输出旋转矢量进行断裂故障判别,建立多种频率耦合状态下的无接触式检测分布模型,通过同频率分量的叠加控制方法,提取兆瓦级变速发电机组引出线断裂故障状态下的参数分布特征量,结合参数优化辨识和特征差异性分析,实现兆瓦级变速发电机组引出线断裂故障的无接触式检测。仿真结果表明,采用该方法进行兆瓦级变速发电机组引出线断裂故障检测的准确性较高,特征分辨能力较好,具有较强稳定性,提高了兆瓦级变速发电机组引出线断裂故障诊断和无接触检测能力。

In order to realize contactless detection of lead-out fault of megawatt variable-speed generator set,a contactless detection method of lead-out fault of megawatt variable-speed generator set based on abnormal frequency detection of grid-connected inverter is proposed.the current response component and voltage component of the outgoing line of megawatt variable-speed generator set analyzed,and the parameter characteristics of the outgoing line of megawatt variable-speed generator set are combined with frequency coupling control method to constructs the decoupling control model of inverter and power grid,the fracture fault is discriminated according to the input and output rotation vectors of megawatt variable-speed generator set,an the non-contact detection distribution model is established under various frequency coupling states,The feature quantity of parameter distribution in the fault state of outlet line of megawatt variable speed generator set is extracted,and the contactless detection of outlet line fault of megawatt variable speed generator set is realized by combining parameter optimization identification and feature difference analysis.The simulation results show that this method has high accuracy,good feature resolution and strong stability,which improves the fault diagnosis and contactless detection ability of the outgoing line of megawatt variable speed generator set.