google sponsored a contest, the little box challenge, to design a small, efficient, power inverter.

• Must be able to handle up to 2 kVA loads
• Must achieve a power density of equal to or greater than 50 W/in3
• Must be able to handle loads with power factors from 0.7–1, leading and lagging in an islanded mode
• Must be in a rectangular metal enclosure of no more than 40 in3
• Will be taking in 450 V DC power in series with a 10 Ω resistor
• Must output 240 V, 60 Hz AC single phase power
• Must have a total harmonic distortion + noise on both voltage and current of < 5%
• Must have an input ripple current of < 20%
• Must have an input ripple voltage of < 3%
• Must have a DC-AC efficiency of greater than 95%
• Must maintain a temperature of no more than 60°C during operation everywhere on the outside of the device that can be touched.

this is what I came up with. it did not win.

unlike the winning entry, this device uses only standard, commercially available, off the shelf parts.

• • • • • • • • WARNING * * * * * * * *

This device contains potentially lethal voltages.

This device does not comply with consumer electrical safety requirements.

DO NOT USE OR BUILD THIS UNLESS YOU ARE FAMILIAR WITH THE SAFETY PRECAUTIONS FOR WORKING WITH HIGH VOLTAGE.