Inverter

Decently well documented inverter system, 2 kW, using transformers:

• Disadvantage: about 70-80% efficient; appears that non-solid state inverters are less efficient than solid state.
• Commercial, solid-state inverters are 90-95% efficient (ex., [1])

Another, smaller-power, less documented example:

http://www.i4at.org/lib2/inverter.htm

DIY Inverters

Microwave Transfomers

I found this site, where they propose to use modified transformers from old microwave ovens, you’d need about 10 broken micros’ and 20 N-type power MOSFET’s for a 9kw unit.

http://electronics-diy.com/electronic_schematic.php?id=609

Open Source 100kW Electric Vehicle Controller/Inverter

This is a senior project for electrical vehicles. Its out is 3 phase. This could be of interest for the induction furnace. The design is very simple. Not sure if it was ever implemented. It is made mostly from IC's. Maybe these could be replaced to reduce some of the costs.

http://eet.etec.wwu.edu/ahmanna/project/docs/Prodject%20description.pdf

Solar Grid-Intertie Inverter

http://www.timnolan.com/index.php?page=solar-grid-intertie-inverter

Scalable Commercial Inverter

The company MGE UPS seems to have merged with another one named APC, but the concept is good. This inverter is scalable up to 20kw. It looks like the inverters are designed to share some resources and are just connected in series.

http://rep.mgeups.com/3ppdf/s4.pdf

A FLEXIBLE INVERTER CONTROLLER FOR PROTOTYPES

See Also

• Inverters_&_Grid_Intertie
• Inverter_Concept
• Arduino_Inverter