Electronic – arduino – Constructing a 12VDC to 230VAC 1-phase inverter

arduinoinverter

Can anyone help me check why the inverter circuit I built outputs only 165 V at no load instead of the proposed 230 V. It can't even light a bulb because of that. I tried adjusting values of filter capacitor but output remained low.

The inverter circuit and output voltage wave is attached. I'm using a 12 V battery, Arduino Uno, IR2110, and a centre-tapped transformer. I notice that each time I switch on the inverter at no load, the battery terminal voltage drops from 13 V to 12.4 V. I think that voltage is still OK to get about 230 V at output.

Is my circuit and components I used OK? Please your suggestion will be highly welcome. Thanks.

NOTE: The scope trace is inverter output voltage which I measured through a 230v/6v step-down transformer. I expected it to give 8.48v peak (equivalent to 6v RMS), but it rather gave about 6v peak.

Arduino Uno-based inverter

output voltage with 0.47uF filter

Best Answer

I suspect that you are under-driving the low-voltage primary.

That 12-0-12 rating on the low-voltage side is the RMS value of the AC. The peak voltage, when used as a regular mains transformer, will be \$ 12\sqrt 2 \$. Since you are driving it with a peak of 12 V then the output could be expected to be \$ \frac {230}{\sqrt 2} = 162 \ \text V \$ which is very close to your reading.

You need to increase the turns ratio by \$ \sqrt 2 \$. An 8.5 - 0 - 8.5 transformer would be ideal.