Problems with inverter connected to output reactor

When using a frequency converter to control a motor, how many meters away from the frequency converter does it take to add an output reactor? I have seen someone else's Schneider frequency converter before. The motor was nearly 300 meters away from the frequency converter, and there was no output reactor. When it was powered on, the frequency converter reported a 3-phase short circuit fault. In fact, the 3-phase output connection method was completely correct. They modified some parameter values ​​in the frequency converter (I don't know what parameters they were), and the frequency converter can work normally. If the Siemens 440 or 6ES70 frequency converter can also modify some parameters to allow the motor to work normally when it is far away from the frequency converter? What are the specific parameters?

Answer: 1. There are several options on the inverter output side:

1) Output reactor: When the length of the cable from the inverter to the motor is greater than the specified value of the product, an output reactor should be added to compensate for the charging and discharging effects of the coupling capacitor when the motor is running with a long cable, to avoid overcurrent of the inverter. There are two types of output reactors. One type of output reactor is an iron core reactor, which is used when the carrier frequency of the inverter is less than 3KHZ. The other type of output reactor is a ferrite type, which is used when the carrier frequency of the inverter is less than 6KHZ. The purpose of adding an output reactor to the output end of the inverter is to increase the wire distance from the inverter to the motor. The output reactor can effectively suppress the instantaneous high voltage generated when the IGBT of the inverter is switched, and reduce the adverse effects of this voltage on the cable insulation and the motor. At the same time, in order to increase the distance between the inverter and the motor, the cable can be appropriately thickened to increase the insulation strength of the cable, and unshielded cables should be used as much as possible.

2) Output dv/dt filter Output dv/dt inductor. The output dv/dt inductor is used to limit the rising rate of the inverter output voltage to ensure normal insulation of the motor.

3) Sinusolidal filters make the output voltage and current of the inverter close to sine waves, reducing the harmonic domain coefficient of the motor and the insulation pressure of the motor.

2. When using a frequency converter to control the motor, if the distance between the motor and the frequency converter exceeds a certain number of meters, an output reactor needs to be added.

Different brands of inverters have different specified values. In addition, some brands of inverters include output reactors as part of their standard supply, and you cannot choose not to. In some other brands of inverters, 380V products do not have output reactors as standard, but 690V products must have output reactors as standard.

3. They modified some parameter values ​​in the inverter (I don’t know what parameters they were), and the inverter can work normally.

The carrier frequency parameters may have been modified.