As a very popular control device in the field of electronic control, the frequency converter almost penetrates into every corner of industrial production activities. However, for some newcomers or newcomers who are just beginning to contact the inverter, they are still relatively unfamiliar and mysterious, especially if the inverter fails, it is easy to get started. Today, based on years of experience in using and overhauling inverters, I have summarized the four major faults common to inverters and given the relevant incentives for causing them.
First, over current (short circuit)
Overcurrent faults are most common among various faults in the frequency converter. This fault is mostly caused by the following problems: First, as long as the inverter speeds up, it reports a fault, indicating that the overcurrent is very serious, mostly the load short circuit, mechanical parts are stuck, the inverter module is soft breakdown damage and the acceleration time is over. Shortly caused; secondly, the inverter reports a fault when it is powered, and it cannot be “reset” to be eliminated. Most of it is caused by damage to the internal drive circuit of the inverter and damage to the current detection circuit. The last phenomenon is the most extreme. When the power is turned on instantaneously or after a short delay, it directly causes the upper air to trip and the internal fuselage is blown out or sparks. The inverter rectifier unit and the power inverter component directly cause breakdown failure. Second, overvoltage
This type of fault phenomenon is also often found in inverter faults. In addition to eliminating the supply voltage is too high, there is also a case of such a fault – when the inverter is stopped. The main reason for this may be caused by a slow deceleration time or a problem with the braking resistor and the brake unit.
Third, under voltage
The above overvoltage fault corresponds to the undervoltage fault of the inverter. Generally, the power supply voltage is too low. It may also be caused by the following reasons: the power supply phase loss, the open circuit fault of one bridge arm of the rectifier circuit, and the main circuit If the capacity of the filter electrolytic capacitor becomes small or a problem occurs in the voltage detection circuit, the inverter may experience an undervoltage fault. In addition, if the internal snubber resistance of the inverter is not cut off by short circuit, an undervoltage fault will occur as long as the inverter is loaded.
Fourth, over temperature
Over-temperature is also a common fault of the inverter. This fault is mostly caused by the temperature of the inverter working environment is too high, the cooling holes are blocked, the cooling fan is damaged, the temperature sensor and the temperature detection circuit are damaged.
Through the above analysis of the four common faults of the inverter (of course, faults such as overload and output imbalance), it is not difficult for the peers to see that the inverter needs to work harder in daily maintenance, and more needs to be done in daily maintenance. We will use it flexibly according to the situation on the spot, and try our best to prevent it before it happens!