How to choose inverter for Roots blower

Roots fan supporting inverter is an important means for many manufacturers to achieve energy saving. Some traditional power frequency equipment can also achieve more energy-saving operation by adopting frequency conversion transformation. The whole line of Roots fan products can be equipped with variable frequency control, and for the equipment that needs to be transformed by frequency conversion, Rongheng Fan has summarized  some points for you to pay attention to in the selection of frequency converters

1. Select the inverter according to the load characteristics. There are many kinds of production machinery, with different performance and process requirements, and their torque characteristics are also different. Therefore, before applying the frequency converter, it is necessary to first understand the nature of the load carried by the motor, that is, the load characteristics, and then select the frequency conversion. device.

There are three types of loads: constant torque load, square torque load and constant power load. Different types of loads should select different types of inverters.

2. When selecting the inverter, the actual motor current value should be used as the basis for the selection of the inverter, and the rated power of the motor can only be used as a reference. In addition, it should be fully considered that the output of the inverter contains high-order harmonics, which will cause the power factor and efficiency of the motor to deteriorate. When selecting a motor and a frequency converter, an appropriate margin should be reserved to prevent the temperature rise from being too high and affecting the service life of the motor.

3. When the inverter needs to run with a long cable, measures should be taken to suppress the influence of the long cable to the ground coupling capacitance, so as to avoid insufficient output of the inverter. Therefore, the inverter should enlarge the first gear selection or install an output reactor at the output end of the inverter.

Fourth, when the inverter is used to control several motors in parallel, it must be considered that the total length of the cables from the inverter to the motor is within the allowable range of the inverter. If it exceeds the specified value, it is necessary to enlarge one or two gears to select the inverter. In addition, in this case, the control mode of the inverter can only be V/F control mode, and the inverter cannot protect the overcurrent and overload protection of the motor. At this time, a fuse should be added to each motor to achieve protection.