Summary and maybe future work?

A project log for Palm-sized AC Generator

Portable 9V battery powered DC to AC converter with variable frequency

ellie-tEllie T 08/11/2018 at 21:280 Comments

The portable generator was able to induce a sine wave on the secondary coil for frequency range of 55-194 kHz, which achieved the main goal of the project.

However, the circuit seem to get unstable due to kickback of the coils when Potentiometer2 (filter) became small, with voltage spikes as large as 21 V peak to peak! This would cause the circuit to ‘crash’ and need to be reset. Thus for safety reasons the ‘shaping’ potentiometer (filter) is hidden within the box, not for user control.

Future upgrades could increase the stability of the circuit with an op-amp buffer, or an added transistor to amplify the current to drive the coils. A second potentiometer can also be added to increase the range of lower frequencies of the oscillating circuit to achieve the conventional 60 Hz.

If possible, a step-up transformer to can also be added to raise the output to 120V or 240V, which will greatly expand the portable unit’s usability.

i think it'd also be interesting to figure out the output current, and maybe test it out on other small AC-needing devices (and watch them die hahahahah).