12 VDC to 12 VAC SINGLE PHASE VFD Inverter

How can I convert 12 volts DC, 130 amperes, into 12 Volts AC (square wave) at the same amperes, with VARIABLE FREQUENCY from 1 cycle per minute to 2.1 Khz?

Is there any "off the shelf" item that will do this? I know this is an unusual set of parameters.

It is needed to control a 12 VAC motor of unique design.

Any ideas or suggestions would be appreciated.

I hope I am posting in the right forum.

its not that much difficult to generate AC from DC with square wave, u just need a H-Bridge + micro controller or some Oscillating circuit to geneate signal for the H-Bridge in order to achieve ur frequency demand

Thank you for the informative response. The purpose for a 12 Volt very high Amperage VFD inverter, is to control a frequency-sensitive mechanism with a wide response range(1 cycle per minute to 2.1 Khz or higher), and and ability to handle and deliver very high Amperage (130 Amperes), with very little or no transmission loss.

Another challenge that must be met, it to fit the physical space allowed for this unusual VFD gadget. About the size of a shoe box.

In addition to size, there is, in fact a requirement that the controlling power source deliver crisply square-waved 12 Volt AC when powered by a 12 Volt battery bank.

The fantasy is that somewhere there is an off-the-shelf solution to be located.. somewhere.. Apparently too fantastic...

I am not an Electronics Technician, or an Engineer, but it does seem to me the issue is how to generate pulsing DC, frequency of pulses controlled by the Variable Frequency Driver, (or a rotating switch operated by a little variable speed 12 Volt DC motor), output through a 1-to-1 transformer, where the DC pulses become AC current in the secondary coil, with the Alternating Frequency Cycles mirroring the frequency of the DC pulses.

I hope I wasn't too redundant, but there is more specific information on why this unusual conversion is sought.

MOSFET-based H-Bridge is a good option to generate high-power square-wave ..
Here is an example:
**broken link removed**
The easy way to increase the current rating of this bridge is just to connect several MOSFETS in parallel, say 10 power MOSFETs (mounted on a decent heatsink) in each quarter of the bridge should handle 130A current ..

To drive this bridge you need a square wave generator, and 555-timer is a very good candidate for this job, as it can easily generate square waves in the required frequency range ..
Google for 555-timer ..

IanP

Thanks Ian. It looks like the eventual challenge may turn out to be fitting the inverted device into the small space available for it.

Thanks for the helpful advice and the link.

Geoff

Ian is right. You don't have to worry about size much. the 130amp H bridge will happily sit inside a shoe box. Only you need to use high current FETs. Also be sure to include a cooling mechanism such as a FAN.

The only problem is that you need to use a differnt circuit to produce 50% dutycycle from 555 : https://www.simplecircuitdiagram.com/2009/06/17/555-oscillator-with-50-duty-cycle/

or you can use the usual diode circuit.

Hi,
While a 555 timer would be very good, you need to drive the MOSFETs with a hi-lo side driver, or else you're going to face some big problems.
For that you should take a look at IR2110.

www.datasheetcatalog.org/datasheet/irf/ir2110.pdf
www.irf.com/technical-info/appnotes/an-978.pdf
https://www.electro-tech-online.com...303-high-side-vs-low-side-mosfet-drivers.html

Hope this helps.
Tahmid.