Common inspection method when the inverter motor drive circuit is damaged - Database & Sql Blog Articles

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There are various reasons for the damage of the drive. In general, the problem is nothing more than U, V, W three-phase no output, or output imbalance, or output balance but jitter at low frequencies, and start Alarm and so on.
When the fast-melting open circuit of a large inverter or the IGBT inverter module is damaged, the drive circuit is basically impossible to be intact, and it is not easy to replace it with a good fast-melting or IGBT inverter module. Causes the good device that has just been replaced to be damaged again. At this time, it is important to check whether there is a flash mark on the drive circuit. Here, the drive pin connection of the IGBT inverter module can be unplugged first, and the resistance of the six-way drive circuit is the same by using a multimeter electric blockage (but very few The inverter drive circuit is not the same as the six-way resistance: such as Mitsubishi, Fuji and other inverters. If the six-way resistance is basically the same, it can't fully prove that the drive circuit is intact. Then you need to use an electronic oscilloscope to measure the voltage on the six-way drive circuit. The waveform of the six-way driver circuit is consistent when given a start signal; if there is no electronic oscilloscope in hand, you can also try to use a digital electronic multimeter to measure the DC voltage of the driver circuit six.
Generally speaking, the DC voltage on each drive circuit when it is not started is about 10V, and the DC voltage after startup is about 2-3V. If the measurement result is normal, it can be judged that the drive circuit of the inverter is good. of. Then connect the IGBT inverter module to the drive circuit, but remember that in the absence of 100% confidence, the safest method is to disconnect the P of the IGBT inverter module from the DC bus, indirectly in a group of bulbs or A higher power resistor, which protects the IGBT inverter module from being burnt out by the discharge current of the large capacitor in the event of a large current in the circuit.