As general rule if you are going to single phase VFD drive that does not have 3 phase input you have to double the amperage of the motor current but even doing this does not guarantee that you would not fry the drive doing this but there single phase VFD but most of them are a minimum of 240 volt input you might find a 120 volt version but will take a lot of researching and they are going to cost a lot more than a regular VFD 3 phase will cost
First of all you have to use a 3 phase motor to be able to use a 3 phase VFD drive
Now I have seen some where I can not remember what company has these VFD drive that are single phase VFD drive which would work but you would have to have the right motor for this purpose
but like said earlier unless the drive is setup as single phase VDF drive it will not work correctly
Now depending on your current draw on the motor you have there might be a solution to your problem
Not sure you’re stating that correctly. I’ll take my whack at it.
If you use a standard three phase input VFD with a single phase input, the output amperage rating of the VFD should be (at least) two times the amperage required by the motor. It does not mater if it is a single phase or three phase motor, the same derate applies. Amps are amps.
The doubling of rating is an approximate rule of thumb and does not always work with all brands of drives.
The reason for the rating increase is due to the input current as seen by the input rectifiers goes up by the square root of three and the bus capacitors must increase in capacitance due the reduction of input frequency by way of losing two phases. Instead of a rectified 300 Hz pulse rate, the dc bus capacitors only see 100 Hz (with a 50 Hz system). Most drives measure the ac ripple on the dc bus and this causes a fault trip when a high value is seen by the VFD. Many times the fault shows up as an input phase loss. The drive doesn’t actually know anything about the incoming phases, it just knows what the dc bus ripple is high - so the fault doesn’t occur until a high load with a corresponding high bus ripple occurs. This fools many users into thinking the drive bad when it’s just undersized.
There are plenty of VFD’s out there up to about 2.2KW that are single phase in, three phase out. Those can typically made to work with a single phase motor so long as you can disable the output phase loss fault. Some of the really cheap drives don’t have output phase loss because they just measure DC bus current by way of a shunt and extrapolate the AC motor current.
The only manufacturer of a single phase in, single phase out VFD that I am aware of in the industry is Invertek out of the UK, known as the purple drive guys. Check their website for more info, their drive reliably runs a single phase motor without removing caps or other modifications (although I don’t think the drive could possibly work with a centrifugal switch on the starting cap).
One of the things never mentioned in these discussions is the risk for motor bearing failures caused by the eddy currents created in the stator by the PWM switching energy. It’s well known in the industrial world.
Another issue is that VFD’s will cause a rise in stator temperature, again due to PWM switching and the resulting harmonic distortion. I doubt it would matter on a submersible pump with a duty cycle. But the potential for stator heating is real.
If you have any VFD questions, ask away. No specific single phase motor experience but I know a few things about drives. It’s all 3 phase industrial but yeah, that’s the day job. Drives up to 700V and 5MW.