【Daily Question 20090225】In what aspects does the power consumption of the inverter itself manifest itself?

Electrofusors, cooling fans, braking losses, etc

In traditional variable-frequency speed control systems composed of general-purpose frequency converters, asynchronous motors, and mechanical loads, when the potential energy load driven by the motor is lowered, the motor may enter a regenerative braking mode； Or when the motor slows down from high speed to low speed (including stopping), the frequency can drop sharply; however, due to the mechanical inertia of the motor, it may enter a regenerative generation mode. The mechanical energy stored in the transmission system is converted by the motor into electrical energy, which is then sent back to the DC circuit of the inverter through the six freewheeling diodes of the inverter. At this time, the inverter is in rectification mode. At this point, if no measures are taken to consume the energy within the inverter, this energy will cause the voltage of the energy storage capacitor in the intermediate circuit to rise. If braking occurs too quickly or the mechanical load is of the elevator type, this energy can cause damage to the inverter!

The greatest loss is the high-order harmonic pollution caused to the power grid; aside from the losses resulting from the resistance values of the fans and thyristors, there are no significant other losses. This post was last edited by HandsomeToTheExtreme on 2009-2-25 at 09:57.]

It is related to the type of inverter, its operating status, frequency of use, etc., but it is difficult to answer. However, the efficiency of inverters operating at frequencies below 60Hz is approximately 94% to 96%, and losses can be estimated based on this figure. But for inverters with built-in regenerative braking (FR-K), if the losses that occur during braking are also taken into account, the power consumption increases, and this needs to be taken into consideration when designing the control panel.

Heat generation during the power conversion process is also part of it.

Power consumption of inverter motors, cooling fans, braking losses, rectification, control cabinets, etc

Including fans, heat generation, and external interference

Fans, thyristors, heat generation, braking losses

The losses inherent in the inverter itself should include the following: 1) Power consumption of the fan motor, 2) Energy losses during the rectification and inversion processes

Mainly the cooling fan and the switching losses of IGBTs (the cause of heat generation in inverters)!