中频电炉广泛应用于钢铁、铸造、特钢等相关领域，不同的应用领域对中频电源有不同的要求，只有在熟练掌握这些电路的基本工作原理和功率器件基本特性的基础上，才能迅速、准确地分析、判断故障原因，采取有效的措施排除故障。 Intermediate frequency electric furnace is widely used in steel, casting, special steel, etc, different applications have different requirements of the medium frequency power, only in mastering the basic working principle of the circuit and power device, on the basis of the basic features, can quickly and accurately judge fault reason analysis, and take effective measures to eliminate failures. 　　在此，对产品典型故障进行探讨分析，希望能给您提供帮助。 At this point, discusses and analyzes the typical of product failure, the hope can give you help. 　　1、开机，设备不能正常起动 1, boot, equipment not starting properly 　　故障现象：起动时直流电流大，直流电压和中频电压低，设备声音沉闷。 Fault phenomenon: direct current when starting, low voltage dc voltage and frequency, equipment sounds boring. 　　分析处理：逆变桥有一桥臂的晶闸管可能短路或开路，造成逆变桥三臂桥运行。用示波器分别观察逆变桥的四个桥臂上的晶闸管管压降波形，若有一桥臂上的晶闸管的管压降波形为一线，该晶闸管已穿通；若为正弦波，该晶闸管未导通。更换已穿晶闸管；查找晶闸管未导通的原因。 Analysis: there is a bridge inverter bridge arm of the thyristor may short circuit or open circuit, inverter bridge three arm bridge operation. Oscilloscope were observed four bridge inverter bridge thyristor (tube voltage waveform on the arm of the if there is an arm of the bridge thyristor tube voltage waveform is a line, the thyristor has been through; If the sine wave, the thyristor conduction. Replacement has been wearing thyristor; Find the thyristor conduction of reason. 　　2、设备能起动，但工作状态不对 2, the equipment can start, but the condition is wrong 　　故障现象：设备能正常顺利起动，当功率升到某一值时，过压或过流保护。 Fault phenomenon: equipment can normal starting smoothly, when power up to a certain value, the over-voltage or over-current protection. 　　分析处理：分两步查找故障原因： Analysis: to find the cause of the problem in two steps: 　　1）、先将设备空载运行，观察电压能否升到额定值。若电压不能升到额定值，并且多次在电压某一值附近过流保护。这可能是补偿电容或晶闸管压不够造成的，但也不排除是电路某部分打火造成的； 1), equipment running light first, observation can rise to the rating voltage. If can't rise to the rating voltage, and repeatedly over-current protection in the vicinity of a voltage value. This may be a compensation or thyristor voltage is not enough to cause, but does not rule out is caused by light circuit part; 　　2）、若电压能升到额定值，可将设备转入重载运行，观察电流值是否能达到额定值，若电流不能升到额定值，并且多次在电流某一值附近过流保护，这可能是大电流干扰。要特别注意中频大电流的电磁场对控制部分和信号线的干扰。 2), if the voltage can rise to the ratings, but putting the equipment into overload operation, observe whether the current value can reach rating, if can't rise to the current ratings, and near the current a value many times over-current protection, this may be a large current interference. It is important to pay special attention to the intermediate frequency electromagnetic field to control the part of the large current interference and signal lines. 　　3、设备正常运行时，易出现的故障 3, equipment normal operation, easy to appear the fault 　　故障现象：设备运行正常，但在正常过流保护动作时，烧毁多支KP晶闸管和快熔。 Fault phenomenon: equipment operation is normal, but in normal over-current protection action, burning more than KP thyristor and the fast fuse. 　　分析处理：过流保护时，为了向电网释放平波电抗器的能量，整流桥由整流状态转到逆变状态，这时如果а＞1500就有可能造成有源逆变颠覆，烧毁多支晶闸管和快熔,开关跳闸，并伴随有巨大的电流短路爆炸声。对变压器产生较大的电流和电磁力冲击，严重时会损坏变压器。 Analysis: over-current protection, in order to to the grid flat wave reactor of energy released, rectifier bridge rectifier state to the inverter state, at this moment if а > 1500 is likely to cause active inverter, burning more than thyristor and the fast fuse, switch trip, and is accompanied by huge short-circuit current explosion. A bigger current and electromagnetic force impact of transformer, serious will damage the transformer.