Problems that should be paid attention to when selecting frequency converter

When the power frequency motor is driven by frequency converter, the current of the motor will increase by 10-15%, and the temperature rise will increase by about 20-25%.


When using a frequency converter to control a high speed motor, there will be more high order harmonics. These higher harmonics will increase the output current of the converter. Therefore, when choosing frequency converter, it should be larger than ordinary motor.

When winding motor is prone to overcurrent trip compared with ordinary squirrel cage motor, it should select a frequency converter which is slightly larger than the usual capacity.

When using inverter to drive gear reducer motor, the scope of application is restricted by the lubrication mode of gear rotation part. When exceeding the rated speed, the risk of oil run out may occur.

By using the motor current value as the basis for selecting the frequency converter, the rated power of the motor is only for reference.

The output of inverter is rich in high-order harmonics, which will reduce the power factor and efficiency of the motor.

If the frequency converter is to run long cable, the influence of the cable on the performance should be considered. If necessary, special cables should be selected. To compensate for this problem, the transducer should be amplified from one to two files.

High temperature, frequent switch, high altitude and other special occasions will make the capacity of the inverter rain down. It is recommended that the transducer be selected according to the amplification one.

When compared with the industrial frequency power supply, the output capacity of the synchronous motor driven by the inverter will be reduced by 10~20%.

Under the condition of peak load and oil pressure pump, such as compressor, vibrator and so on, it is necessary to fully understand the operation frequency and choose a larger frequency converter.