故障现象一台SCX型线切割机在使用数年后,发生无规律的失步,严重时,步进电机只能抖动,不能正常进给。经检查,运算和控制部分正常,步进电机和线路接线也无故障,只有步进电源波纹较大,疑为故障由滤波不良所致,更换滤波电容后,故障消除。因此,断定上述怀疑是正确的,但是,为什么电源滤波不良会引起失步呢?这种失步又与哪些因素有关呢?针对这个问题,本文作如下分析分析一假设电源无滤波时的情况分析。电源失去滤波后,不再是纯直流,对于桥式整流,电源输出是以π为周期,按正弦规律变化的脉动直流,其脉动幅值即整流前 Symptom A SCX-type wire cutting machine in use after a few years, the occurrence of irregular loss of synchronization, serious, the stepper motor can only shake, can not feed normally. After examination, operation and control part of the normal, stepper motor and wiring wiring is also faultless, only large stepper power ripple, suspected fault caused by poor filtering, filter capacitor replacement, the fault is eliminated. Therefore, to conclude that the above suspicion is correct, but why the poor power filter will cause loss of synchronization? What are the factors associated with this out-of-step? In response to this issue, the following analysis and analysis of a hypothetical power supply without filter case analysis . After the power loss filter, is no longer pure DC, the bridge rectifier, the power output is a π cycle, according to sinusoidal changes in pulsating DC, the pulsation amplitude that is rectified