励磁整流柜可控硅故障模拟及分析

Simulation and Analysis of Thyristor Fault in Excitation Rectifier Cabinet

摘要:

发电机励磁系统整流柜是实现励磁调节的基本单元，故障后果将会很严重。整流桥故障是励磁整流柜最常见的故障之一，为了在发生故障前提前预判出故障以及故障发生后能够准确分析故障发生的原因，有必要研究整流桥故障发生的各种情况。文中归纳了整流桥的故障类型，通过Matlab/Simulink软件搭建模型，对桥臂短路、桥臂不导通、脉冲丢失、提前导通、延时触发等故障条件下的整流桥输入及输出电压、励磁变压器副边电流的仿真波形进行分析；通过对某电厂的实际故障录波波形进行验证，仿真波形与实际波形基本一致。当发电机励磁整流柜出现故障时，可通过所模拟的三相全控整流桥各种故障条件下的波形进行对比分析，确定故障类型并快速分析出故障点。

Abstract:

Rectifier cabinet of generator excitation system is the basic unit to realize excitation regulation, and rectifier bridge fault is one of the most common faults in excitation rectifier cabinet. In order to predict the fault in advance and accurately analyze the cause of the fault after the fault occurs, it is necessary to study various situations of rectifier bridge fault. The fault types of rectifier bridge are summarized, a model through Matlab/Simulink software is built, and the simulation waveforms of the input and output voltage of rectifier bridge and the secondary side current of excitation transformer are analyzed under several fault conditions such as short circuit and nonconduction of bridge arm, pulse loss, early conduction and delayed [JP]triggering. Through the verification of the actual fault recording waveform of a power plant, the simulation waveform is basically consistent with the actual waveform. When there is a fault occurred in excitation rectifier cabinet of generator, the fault type can be determined by analyzing and comparing the waveform under various fault conditions of the three-phase fully controlled rectifier bridge simulated by Matlab/Simulink software, and the fault point can be quickly analyzed.