Auto-tuning simplifies application of permanent magnet motors

One advantage of the new FR-E800 drives is their ability to auto-tune both induction and PM motors. The drives will be available for 200-, 400- and 600-volt applications. The tuning function is controlled by software parameters for values such as RPM, speed, frequency, full load and current voltage. “OEM engineers need only input key information from the motor nameplate into the parameters of the drive and push auto-tune,” says Rhodes. “There may be minor tweaking required, but basically you’re ready to go. It’s a major time-saver for engineers.”This auto-tuning function gives a VFD’s vector control algorithm better than stock parameters to control the motor flux and, ultimately, the output torque performance of a motor. The new Mitsubishi Electric drives also enable operation of other manufacturers’ induction and PM motors, which will likely help increase the use of PM motors in applications that require reduced energy consumption. “Machine builders typically use the same motor in different machines, so auto-tuning is a simple matter of replication,” he adds. “Once you set it, you’re done, regardless of the motor count.“While VFDs make motorized systems run more efficiently, whether the type of motor is induction, permanent magnet or synchronous reluctance, OEMs in critical applications need to explore solutions to mitigate harmonics, filter out line noise and minimize the impact on the power grid,” says Rhodes. “At Mitsubishi Electric, we have many VFD filter options to deal with these issues.”