Author Topic: Running Hovermotor from VFD  (Read 1170 times)

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Offline made2hackTopic starter

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Running Hovermotor from VFD
« on: January 10, 2019, 10:29:27 am »
Hello all,

Can I drive a hovermotor from a VFD intended for induction motors? Or do I need to get a hobby ESC? I mean I know the hovermotor is a so-called brushless DC, but it is still wired as 3 phase motor. Would the VFD work? Or do I risk killing the motor?

Thanks,

Offline capt bullshot

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Re: Running Hovermotor from VFD
« Reply #1 on: January 10, 2019, 10:44:00 am »
Short answer: no.

Long answer: The DC brushless requires some kind of position feedback to the driver - can be sensorless. A typical VFD for induction motors doesn't have position feedback, just outputs a ramping up and down frequency with the amplitude (voltage) proportional to the frequency (U/F mode).
If one fiddles with these settings (ramp speed, full speed voltage/frequency and voltage raising with frequency) it might be achieveable to get the motor running - but it won't be reliable. E.g. at a different mechanical load, the ramp speed won't match the different needs of the motor then, the motor will loose sync to the frequency and cease to create torque (in German this is called "kippen", don't know the English term) and stall in turn. Typically this causes the VFD to stop due to overcurrent, but if the VFD isn't matched to the motor size, it'll continue to push power into the stalled motor which will cause the motor to burn.

So you'd better use a dedicated BL DC motor controller.
« Last Edit: January 10, 2019, 10:45:52 am by capt bullshot »
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Offline beanflying

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Re: Running Hovermotor from VFD
« Reply #2 on: January 10, 2019, 10:46:16 am »
EDIT SNAP to capt bullshot :-DD


Short answer is NO. Were you hoping to use AC power to drive the motor? And for what retasking purpose?

Most of the hoverboard motors I have seen also use Hall effect sensors as part of the control loop? The reason they tend to get used on Wheeled R/C or hoverboards is you can get better torque from the drive.

Depending on how they are wired you should be able to use a Non Sensored BDLC ESC by simply not using the Hall Sensors. Or you may (no guarantee) be able to get a R/C Car sensored controller to work with the motor too.
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Offline made2hackTopic starter

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Re: Running Hovermotor from VFD
« Reply #3 on: January 12, 2019, 11:29:56 am »
Thanks,

I did not want to use a VFD, I just wanted to power on the hovermotor until I get an ESC to come in.



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