We have the power source with fluctuating frequency ranging from 40 to 52 Hz, 220 VAC. We wish to use VFDs to provide a constant frequency output with 220 VAC, at 50 Hz. Can anybody inform us whether this variation of 220 VAC with 40-50 Hz. frequency can be accepted by a VFD?

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Best regards,
Arvind

 

Arvind,

Naturally, you will need to speak with representatives from some of the manufacturers of these devices, of which there are many: Rockwell, Seimens, Hitachi, Mitsubishi, almost any significant indistrial electrical/electronics mnufacturer, but I think you will be pleasantly surprised. Almost all, if not all, of these devices work at first rectifying the incoming power into a full DC bus, then "inverting" that DC into the variable frequency/variable voltage output to the driven motors.

It seems to me that this system would be relatively unconcerned with the frequency of the input, especially if the voltage is reasonably steady. I would think a VSD would be ideally suited for this kind of problem.

-- Mike McLeod

 

Keep in mind that VFDs are meant to run motors. The output waveform isn't a sine wave and is usually full of spikes of varying heights. If you are looking to run anything other than a motor, then you would want an inverter. Xantrex, among others, makes those.

 

Arvind,

I have used VFD of all makes say TB Woods, ABB, Allen Bradley, Kirloskar, etc. etc. As per my experience, minimum tolerable frquency for these drives is 47 Hz.

Arif