基于标幺化均值的大功率PWM整流器故障诊断

Fault Diagnosis for Large-Capacity PWM Rectifier Based on Normalized Average

在对大功率PWM整流器的网侧故障电流畸变现象进行研究的基础上,通过引入交直流中点电位差和网侧故障电流的标幺化均值及交流网侧电流的标幺化均值作为故障特征量形成了标幺化均值法.综合其软硬件实现难度及故障诊断速度来看,标幺化均值法在网侧故障电流畸变的情况下诊断PWM整流器主回路的开关管断路故障时比现有方法容易实现,可靠性更高.

In this paper, a novel approach with normalized average mechanism is proposed, which introduces the normalized averages of the voltage across AC and DC neutral points, as well as of the gridside fault currents, as characteristic fault signatures for the diagnosis of large-capacity PWM rectifier with break-down switching devices. Such approach has been proven to be more effective in the aspects of realization and reliability, compared with the existing approaches.